TopBlend:
Here is the
first difference.
There are 290 differences.
is old.
is new.
javax.swing
Class JList
java.lang.Object
java.awt.Component
java.awt.Container
javax.swing.JComponent
javax.swing.JList
-
All Implemented Interfaces:
-
ImageObserver
,
MenuContainer
,
Serializable
,
Accessible
,
Scrollable
-
public class JList
- extends JComponent
- implements Scrollable, Accessible
A component that
displays a list of objects and
allows the user to select one or more
items.
objects from a list.
A separate model, ListModel,
maintains
represents
the contents of the list.
It's easy to display an array or
Vector
vector
of objects, using
the
a
JList constructor that
automatically
builds a
read-only
ListModel instance for you:
// Create a JList that displays strings from an array
String[] data = {"one", "two", "three", "four"};
JList myList = new JList(data);
// Create a JList that displays the superclasses of JList.class, by
// creating it with a Vector populated with this data
Vector superClasses = new Vector();
Class rootClass = javax.swing.JList.class;
for(Class cls = rootClass; cls != null; cls = cls.getSuperclass()) {
superClasses.addElement(cls);
}
JList myList = new JList(superClasses);
// The automatically created model is stored in JList's "model"
// property, which you can retrieve
ListModel model = myList.getModel();
for(int i = 0; i ![](../../diffpics/oold.gif)
// Create a JList that displays the strings in data[]
String[] data = {"one", "two", "three", "four"};
JList dataList = new JList(data);
// The value of the JList model property is an object that provides
// a read-only view of the data. It was constructed automatically.
for(int i = 0; i < model.getSize(); i++) {
System.out.println(model.getElementAt(i));
}
A ListModel can be supplied directly to a JList by way of a constructor or the setModel method. The contents need not be static - the number of items, and the values of items can change over time. A correct ListModel implementation notifies the set of javax.swing.event.ListDataListeners that have been added to it, each time a change occurs. These changes are characterized by a javax.swing.event.ListDataEvent, which identifies the range of list indices that have been modified, added, or removed. JList's ListUI is responsible for keeping the visual representation up to date with changes, by listening to the model.
JList doesn't support scrolling directly. To create a scrolling list you make the JList the viewport view of a JScrollPane. For example:
![](../../diffpics/oold.gif)
JScrollPane scrollPane = new JScrollPane(dataList);
// Or in two steps:
JScrollPane scrollPane = new JScrollPane();
scrollPane.getViewport().setView(dataList);
Simple, dynamic-content, JList applications can use the DefaultListModel class to maintain list elements. This class implements the ListModel interface and also provides a java.util.Vector-like API. Applications that need a more custom ListModel implementation may instead wish to subclass AbstractListModel, which provides basic support for managing and notifying listeners. For example, a read-only implementation of AbstractListModel:
By default the JList selection model allows any combination of items to be selected at a time, using the constant MULTIPLE_INTERVAL_SELECTION. The selection state is actually managed by a separate delegate object, an instance of ListSelectionModel. However JList provides convenient properties for managing the selection.
// This list model has about 2^16 elements. Enjoy scrolling.
ListModel bigData = new AbstractListModel() {
public int getSize() { return Short.MAX_VALUE; }
public Object getElementAt(int index) { return "Index " + index; }
};
![](../../diffpics/oold.gif)
String[] data = {"one", "two", "three", "four"};
JList dataList = new JList(data);
dataList.setSelectedIndex(1); // select "two"
dataList.getSelectedValue(); // returns "two"
The selection state of a JList is managed by another separate model, an instance of ListSelectionModel. JList is initialized with a selection model on construction, and also contains methods to query or set this selection model. Additionally, JList provides convenient methods for easily managing the selection. These methods, such as setSelectedIndex and getSelectedValue, are cover methods that take care of the details of interacting with the selection model. By default, JList's selection model is configured to allow any combination of items to be selected at a time; selection mode MULTIPLE_INTERVAL_SELECTION. The selection mode can be changed on the selection model directly, or via JList's cover method. Responsibility for updating the selection model in response to user gestures lies with the list's ListUI.
A correct ListSelectionModel implementation notifies the set of javax.swing.event.ListSelectionListeners that have been added to it each time a change to the selection occurs. These changes are characterized by a javax.swing.event.ListSelectionEvent, which identifies the range of the selection change.
The preferred way to listen for changes in list selection is to add ListSelectionListeners directly to the JList. JList then takes care of listening to the the selection model and notifying your listeners of change.
Responsibility for listening to selection changes in order to keep the list's visual representation up to date lies with the list's ListUI.
Painting of cells in a JList is handled by a delegate called a cell renderer, installed on the list as the cellRenderer property.
The renderer provides a java.awt.Component that is used like a "rubber stamp" to paint the cells. Each time a cell needs to be painted, the list's ListUI asks the cell renderer for the component, moves it into place, and has it paint the contents of the cell by way of its paint method. A default cell renderer, which uses a JLabel component to render, is installed by the lists's ListUI.
// Display an icon and a string for each object in the list.
class MyCellRenderer extends JLabel implements ListCellRenderer {
final static ImageIcon longIcon = new ImageIcon("long.gif");
final static ImageIcon shortIcon = new ImageIcon("short.gif");
// This is the only method defined by ListCellRenderer.
// We just reconfigure the JLabel each time we're called.
public Component getListCellRendererComponent(
JList list, // the list
Object value, // value to display
int index, // cell index
boolean isSelected, // is the cell selected
boolean cellHasFocus) // does the cell have focus
{
String s = value.toString();
setText(s);
setIcon((s.length() > 10) ? longIcon : shortIcon);
if (isSelected) {
setBackground(list.getSelectionBackground());
setForeground(list.getSelectionForeground());
} else {
setBackground(list.getBackground());
setForeground(list.getForeground());
}
setEnabled(list.isEnabled());
setFont(list.getFont());
setOpaque(true);
return this;
}
}
myList.setCellRenderer(new MyCellRenderer());
Another job for the cell renderer is in helping to determine sizing information for the list. By default, the list's ListUI determines the size of cells by asking the cell renderer for its preferred size for each list item. This can be expensive for large lists of items. To avoid these calculations, you can set a fixedCellWidth and fixedCellHeight on the list, or have these values calculated automatically based on a single prototype value:
JList bigDataList = new JList(bigData);
// We don't want the JList implementation to compute the width
// or height of all of the list cells, so we give it a string
// that's as big as we'll need for any cell.
JList doesn't implement scrolling directly. To create a list that scrolls, make it the viewport view of a JScrollPane.
JScrollPane scrollPane = new JScrollPane(myList);
// Or in two steps:
JScrollPane scrollPane = new JScrollPane();
scrollPane.getViewport().setView(myList);
JList doesn't provide any special handling of double or triple (or N) mouse clicks, but it's easy to add a MouseListener if you wish to take action on these events. Use the locationToIndex method to determine what cell was clicked.
MouseListener mouseListener = new MouseAdapter() {
public void mouseClicked(MouseEvent e) {
if (e.getClickCount() == 2) {
int index = list.locationToIndex(e.getPoint());
System.out.println("Double clicked on Item " + index);
}
}
};
list.addMouseListener(mouseListener);
Warning: Swing is not thread safe. For more information see
Swing's Threading Policy
.
Warning: Serialized objects of this class will not be compatible with future Swing releases.
The contents of a JList can be dynamic, in other words, the list elements can change value and the size of the list can change after the JList has been created. The JList observes changes in its model with a swing.event.ListDataListener implementation. A correct implementation of ListModel notifies it's listeners each time a change occurs. The changes are characterized by a swing.event.ListDataEvent, which identifies the range of list indices that have been modified, added, or removed. Simple dynamic-content JList applications can use the DefaultListModel class to store list elements. This class implements the ListModel interface and provides the java.util.Vector API as well. Applications that need to provide custom ListModel implementations can subclass AbstractListModel, which provides basic ListDataListener support. For example:
![](../../diffpics/oold.gif)
// This list model has about 2^16 elements. Enjoy scrolling.
![](../../diffpics/oold.gif)
![](../../diffpics/oold.gif)
![](../../diffpics/oold.gif)
ListModel bigData = new AbstractListModel() {
public int getSize() { return Short.MAX_VALUE; }
public Object getElementAt(int index) { return "Index " + index; }
};
JList bigDataList = new JList(bigData);
// We don't want the JList implementation to compute the width
// or height of all of the list cells, so we give it a string
// that's as big as we'll need for any cell.
JList uses a java.awt.Component, provided by a delegate called the cellRendererer, to paint the visible cells in the list. The cell renderer component is used like a "rubber stamp" to paint each visible row. Each time the JList needs to paint a cell it asks the cell renderer for the component, moves it into place using setBounds() and then draws it by calling its paint method. The default cell renderer uses a JLabel component to render the string value of each component.
// Display an icon and a string for each object in the list.
![](../../diffpics/oold.gif)
![](../../diffpics/oold.gif)
![](../../diffpics/oold.gif)
![](../../diffpics/oold.gif)
![](../../diffpics/oold.gif)
class MyCellRenderer extends JLabel implements ListCellRenderer {
final static ImageIcon longIcon = new ImageIcon("long.gif");
final static ImageIcon shortIcon = new ImageIcon("short.gif");
// This is the only method defined by ListCellRenderer.
// We just reconfigure the JLabel each time we're called.
public Component getListCellRendererComponent(
JList list,
Object value, // value to display
int index, // cell index
boolean isSelected, // is the cell selected
boolean cellHasFocus) // the list and the cell have the focus
{
String s = value.toString();
setText(s);
setIcon((s.length() > 10) ? longIcon : shortIcon);
if (isSelected) {
setBackground(list.getSelectionBackground());
setForeground(list.getSelectionForeground());
}
else {
setBackground(list.getBackground());
setForeground(list.getForeground());
}
setEnabled(list.isEnabled());
setFont(list.getFont());
setOpaque(true);
return this;
}
}
String[] data = {"one", "two", "three", "four"};
JList dataList = new JList(data);
dataList.setCellRenderer(new MyCellRenderer());
JList doesn't provide any special support for handling double or triple (or N) mouse clicks however it's easy to handle them using a MouseListener.
Use the JList method locationToIndex() to determine what cell was clicked.
final JList list = new JList(dataModel);
MouseListener mouseListener = new MouseAdapter() {
public void mouseClicked(MouseEvent e) {
if (e.getClickCount() == 2) {
int index = list.locationToIndex(e.getPoint());
System.out.println("Double clicked on Item " + index);
}
}
};
list.addMouseListener(mouseListener);
Note that in this example the dataList is final because it's referred to by the anonymous MouseListener class.
Warning: Serialized objects of this class will not be compatible with future Swing releases. The current serialization support is appropriate for short term storage or RMI between applications running the same version of Swing.
As of 1.4, support for long term storage of all JavaBeans
TM
has been added to the java.beans package. Please see
XMLEncoder
.
See
How to Use Lists
in
The Java Tutorial
for further documentation. Also see the article
Advanced JList Programming
in
The Swing Connection
.
-
See Also:
-
ListModel
,
AbstractListModel
,
DefaultListModel
,
ListSelectionModel
,
DefaultListSelectionModel
,
ListCellRenderer
,
DefaultListCellRenderer
Nested Class Summary
|
protected class |
JList.AccessibleJList
This class implements accessibility support for the JList class. |
static class |
JList.DropLocation
A subclass of TransferHandler.DropLocation representing a drop location for a JList. |
Field Summary
|
static int |
HORIZONTAL_WRAP
Indicates
a
"newspaper style"
layout
with
the
cells flowing horizontally then vertically. |
static int |
VERTICAL
Indicates
a vertical layout of cells, in a single column;
the default
layout.
layout: one column of cells.
|
static int |
VERTICAL_WRAP
Indicates
a
"newspaper style" layout with
the
cells flowing vertically then horizontally. |
Constructor Summary
|
JList
()
Constructs a JList with an
empty, read-only,
empty
model. |
JList
(
ListModel
Constructs a JList that displays
the
elements
from
in
the specified,
non-null,
non-null
model. |
JList
(
Object
[] listData)
Constructs a JList that displays the elements in the specified array. |
JList
(
Vector
<?> listData)
Constructs a JList that displays the elements in the specified Vector. |
Method Summary
|
void |
addListSelectionListener
(
ListSelectionListener
Adds a listener to the
list, to be
list that's
notified each time a change to the selection
occurs; the preferred way of listening for selection state changes.
occurs.
|
void |
addSelectionInterval
(int anchor, int lead)
Sets the selection to be the union of the specified interval with current selection. |
void |
clearSelection
()
Clears the
selection;
selection -
after calling this
method,
method
isSelectionEmpty will return true. |
protected
ListSelectionModel
|
createSelectionModel
()
Returns an instance of
DefaultListSelectionModel; called during construction to initialize the list's selection model property.
DefaultListSelectionModel.
|
void |
ensureIndexIsVisible
(int index)
Scrolls the
list within an enclosing
viewport to make the specified cell completely visible. |
protected void |
fireSelectionValueChanged
(int firstIndex, int lastIndex, boolean isAdjusting)
Notifies
JList
ListSelectionListeners
added directly to
that
the
list of
selection
changes made to the selection model.
model has changed.
|
AccessibleContext
|
getAccessibleContext
()
Gets the AccessibleContext associated with this JList. |
int |
getAnchorSelectionIndex
()
Returns the
anchor selection index.
first index argument from the most recent addSelectionModel or setSelectionInterval call.
|
Rectangle
|
getCellBounds
(int index0, int index1)
Returns the
bounding rectangle, in
bounds of
the
list's coordinate system, for the
specified
range of
cells specified by the two indices.
items in JList coordinates.
|
ListCellRenderer
|
getCellRenderer
()
Returns the object
responsible for painting
that renders the
list items. |
boolean |
getDragEnabled
()
Returns whether or not automatic drag handling is enabled.
Gets the dragEnabled property.
|
JList.DropLocation
|
getDropLocation
()
Returns the location that this component should visually indicate as the drop location during a DnD operation over the
component, or null if no location is to currently be shown.
component.
|
DropMode
|
getDropMode
()
Returns the drop mode for this component. |
int |
getFirstVisibleIndex
()
Returns the
smallest list
index
that is currently visible.
of the first visible cell.
|
int |
getFixedCellHeight
()
Returns the
fixed cell height
value
of
--
the
value specified by setting the
fixedCellHeight
property.
property, rather than that calculated from the list elements.
|
int |
getFixedCellWidth
()
Returns the
fixed cell width
value
of
--
the
value specified by setting the
fixedCellWidth
property.
property, rather than that calculated from the list elements.
|
int |
getLastVisibleIndex
()
Returns the
largest list
index
that is currently visible.
of the last visible cell.
|
int |
getLayoutOrientation
()
Returns
the layout orientation property for the list: VERTICAL
JList.VERTICAL
if the layout is a single column of cells,
VERTICAL_WRAP
or JList.VERTICAL_WRAP
if the layout is "newspaper style" with the content flowing vertically then
horizontally,
horizontally
or
HORIZONTAL_WRAP
JList.HORIZONTAL_WRAP
if the layout is "newspaper style" with the content flowing horizontally then vertically. |
int |
getLeadSelectionIndex
()
Returns the
lead selection index.
second index argument from the most recent addSelectionInterval or setSelectionInterval call.
|
ListSelectionListener
|
getListSelectionListeners
()
Returns an array of all the ListSelectionListeners added to this JList
by way of addListSelectionListener.
with addListSelectionListener().
|
int |
getMaxSelectionIndex
()
Returns the largest selected cell
index, or -1 if the selection is empty.
index.
|
int |
getMinSelectionIndex
()
Returns the smallest selected cell
index, or -1 if the selection is empty.
index.
|
ListModel
|
getModel
()
Returns the data model that holds the list of items displayed by the JList component. |
int |
getNextMatch
(
String
prefix, int startIndex,
Position.Bias
Returns the next list element
whose toString value
that
starts with
the given
a
prefix. |
Dimension
|
getPreferredScrollableViewportSize
()
Computes the size of
the
viewport needed to display visibleRowCount rows. |
Object
|
getPrototypeCellValue
()
Returns the
"prototypical"
cell
value
width of the "prototypical cell"
-- a
value
cell
used
to calculate a fixed width and height
for
cells.
the calculation of cell widths, because it has the same value as all other list items.
|
int |
getScrollableBlockIncrement
(
Rectangle
visibleRect, int orientation, int direction)
Returns the distance to scroll to expose the next or previous block. |
boolean |
getScrollableTracksViewportHeight
()
Returns true if this JList is displayed in a JViewport and the viewport is taller than
the list's
JList's
preferred height, or if the layout orientation is VERTICAL_WRAP and
visibleRowCount <= 0; otherwise returns false.
|
the number of visible rows is
<= 0; otherwise returns false.
boolean |
getScrollableTracksViewportWidth
()
Returns true if this JList is displayed in a JViewport and the viewport is wider than
the list's
JList's
preferred
width,
width;
or if the layout orientation is HORIZONTAL_WRAP and
visibleRowCount <= 0; otherwise returns false.
|
the visible row count is
<= 0; otherwise returns false.
int |
getScrollableUnitIncrement
(
Rectangle
visibleRect, int orientation, int direction)
Returns the distance to scroll to expose the next or previous row (for vertical scrolling) or column (for horizontal scrolling). |
int |
getSelectedIndex
()
Returns the
smallest
first
selected
cell
index;
the selection
when only a single item
returns -1 if there
is
no
selected
in the list.
item.
|
int[] |
getSelectedIndices
()
Returns an array of all of the selected
indices,
indices
in increasing order. |
Object
|
getSelectedValue
()
Returns the
value for the smallest
first
selected
cell index;
value, or null if
the
selected value
when only a single item
selection
is
selected in the list.
empty.
|
Object
|
getSelectedValues
()
Returns an array of
all
the
values for the
selected
values, in increasing order based on their indices in the list.
cells.
|
Color
|
getSelectionBackground
()
Returns the
background
color
used to draw the background of
for
selected
items.
cells.
|
Color
|
getSelectionForeground
()
Returns the
color used to draw the
selection
foreground
of selected items.
color.
|
int |
getSelectionMode
()
Returns
the current selection mode for the list.
whether single-item or multiple-item selections are allowed.
|
ListSelectionModel
|
getSelectionModel
()
Returns the
value of the
current selection model. |
String
|
getToolTipText
(
MouseEvent
Returns
Overrides JComponent's getToolTipText method in order to allow
the
tooltip text
renderer's tips
to be used
for the given event.
if it has text set.
|
ListUI
|
getUI
()
Returns the
ListUI, the
look and feel
(L&F)
object that renders this component. |
String
|
getUIClassID
()
Returns
"ListUI",
the
UIDefaults key
suffix
used to
look up
construct
the name of the
javax.swing.plaf.ListUI class that defines the
look and feel
for
(L&F) class used to render
this component. |
boolean |
getValueIsAdjusting
()
Returns the value of the
selection
data
model's isAdjusting property. |
int |
getVisibleRowCount
()
Returns the
value
preferred number
of
the visibleRowCount property.
visible rows.
|
Point
|
indexToLocation
(int index)
Returns the origin of the specified item in
the list's coordinate system.
JList coordinates.
|
boolean |
isSelectedIndex
(int index)
Returns true if the specified index is
selected, else false.
selected.
|
boolean |
isSelectionEmpty
()
Returns true if nothing is
selected, else false.
selected.
|
int |
locationToIndex
(
Point
Returns
Convert a point in JList coordinates to
the
cell
closest
index
closest to
of
the
given location in the list's coordinate system.
cell at that location.
|
protected
String
|
paramString
()
Returns a
String
string
representation of this JList. |
void |
removeListSelectionListener
(
ListSelectionListener
Removes a
selection
listener from the
list.
list that's notified each time a change to the selection occurs.
|
void |
removeSelectionInterval
(int index0, int index1)
Sets the selection to be the set difference of the specified interval and the current selection. |
void |
setCellRenderer
(
ListCellRenderer
Sets the delegate
that is
that's
used to paint each cell in the list. |
void |
setDragEnabled
(boolean b)
Turns on or off
Sets the dragEnabled property, which must be true to enable
automatic drag
handling.
handling (the first part of drag and drop) on this component.
|
void |
setDropMode
(
DropMode
Sets
Set
the drop mode for this component. |
void |
setFixedCellHeight
(int height)
Sets
a fixed value to be used for
the height of every cell in the list. |
void |
setFixedCellWidth
(int width)
Sets
a fixed value to be used for
the width of every cell in the list. |
void |
setLayoutOrientation
(int layoutOrientation)
Defines the way list cells are layed out. |
void |
setListData
(
Object
Constructs a
read-only
ListModel from an array of
objects,
objects
and
calls
then applies
setModel
with this model.
to it.
|
void |
setListData
(
Vector
Constructs a
read-only
ListModel from a Vector and
calls
then applies
setModel
with this model.
to it.
|
void |
setModel
(
ListModel
Sets the model that represents the contents or "value" of the
list, notifies property change listeners,
list
and
then
clears the
list's selection.
list selection after notifying PropertyChangeListeners.
|
void |
setPrototypeCellValue
(
Object
Sets
Computes
the
prototypeCellValue property, and then (if the new value is non-null), computes the
fixedCellWidth and fixedCellHeight properties by
requesting
configuring
the
cell renderer component
cellRenderer to index equals zero
for the
given
specified
value
(and index 0) from
and then computing
the
cell renderer, and using that
renderer
component's preferred size. |
void |
setSelectedIndex
(int index)
Selects a single cell. |
void |
setSelectedIndices
(int[] indices)
Changes the selection to be the
Selects a
set of
indices specified by the given array.
cells.
|
void |
setSelectedValue
(
Object
anObject, boolean shouldScroll)
Selects the specified object from the list. |
void |
setSelectionBackground
(
Color
Sets the
background
color
used to draw the background of
for
selected
items, which cell renderers can use fill selected
cells. |
void |
setSelectionForeground
(
Color
Sets the
foreground
color
used to draw the foreground of
for
selected
items, which cell renderers can use to render text and graphics.
cells.
|
void |
setSelectionInterval
(int anchor, int lead)
Selects the specified interval. |
void |
setSelectionMode
(int selectionMode)
Sets the selection mode for the list.
Determines whether single-item or multiple-item selections are allowed.
|
void |
setSelectionModel
(
ListSelectionModel
selectionModel)
Sets the selectionModel for the list to a non-null ListSelectionModel implementation. |
void |
setUI
(
ListUI
Sets the
ListUI, the
look and feel
(L&F)
object that renders this component. |
void
|
setValueIsAdjusting
(boolean b)
Sets the selection model's valueIsAdjusting property.
|
void
|
setValueIsAdjusting
(boolean b)
Sets the data model's isAdjusting property to true, so that a single event will be generated when all of the selection events have finished (for example, when the mouse is being dragged over the list in selection mode).
|
void
|
setVisibleRowCount
(int visibleRowCount)
Sets the visibleRowCount property, which has different meanings depending on the layout orientation: For a VERTICAL layout orientation, this sets the preferred number of rows to display without requiring scrolling; for other orientations, it affects the wrapping of cells.
|
void
|
setVisibleRowCount
(int visibleRowCount)
Sets the preferred number of rows in the list that can be displayed without a scrollbar, as determined by the nearest JViewport ancestor, if any.
|
void |
updateUI
()
Resets the
ListUI
UI
property
by setting it to
with
the value
provided by
from
the current look and feel. |
Methods inherited from class javax.swing.
JComponent
|
addAncestorListener
,
addNotify
,
addVetoableChangeListener
,
computeVisibleRect
,
contains
,
createToolTip
,
disable
,
enable
,
firePropertyChange
,
firePropertyChange
,
firePropertyChange
,
fireVetoableChange
,
getActionForKeyStroke
,
getActionMap
,
getAlignmentX
,
getAlignmentY
,
getAncestorListeners
,
getAutoscrolls
,
getBaseline
,
getBaselineResizeBehavior
,
getBorder
,
getBounds
,
getClientProperty
,
getComponentGraphics
,
getComponentPopupMenu
,
getConditionForKeyStroke
,
getDebugGraphicsOptions
,
getDefaultLocale
,
getFontMetrics
,
getGraphics
,
getHeight
,
getInheritsPopupMenu
,
getInputMap
,
getInputMap
,
getInputVerifier
,
getInsets
,
getInsets
,
getListeners
,
getLocation
,
getMaximumSize
,
getMinimumSize
,
getNextFocusableComponent
,
getPopupLocation
,
getPreferredSize
,
getRegisteredKeyStrokes
,
getRootPane
,
getSize
,
getToolTipLocation
,
getToolTipText
,
getTopLevelAncestor
,
getTransferHandler
,
getVerifyInputWhenFocusTarget
,
getVetoableChangeListeners
,
getVisibleRect
,
getWidth
,
getX
,
getY
,
grabFocus
,
isDoubleBuffered
,
isLightweightComponent
,
isManagingFocus
,
isOpaque
,
isOptimizedDrawingEnabled
,
isPaintingForPrint
,
isPaintingTile
,
isRequestFocusEnabled
,
isValidateRoot
,
paint
,
paintBorder
,
paintChildren
,
paintComponent
,
paintImmediately
,
paintImmediately
,
print
,
printAll
,
printBorder
,
printChildren
,
printComponent
,
processComponentKeyEvent
,
processKeyBinding
,
processKeyEvent
,
processMouseEvent
,
processMouseMotionEvent
,
putClientProperty
,
registerKeyboardAction
,
registerKeyboardAction
,
removeAncestorListener
,
removeNotify
,
removeVetoableChangeListener
,
repaint
,
repaint
,
requestDefaultFocus
,
requestFocus
,
requestFocus
,
requestFocusInWindow
,
requestFocusInWindow
,
resetKeyboardActions
,
reshape
,
revalidate
,
scrollRectToVisible
,
setActionMap
,
setAlignmentX
,
setAlignmentY
,
setAutoscrolls
,
setBackground
,
setBorder
,
setComponentPopupMenu
,
setDebugGraphicsOptions
,
setDefaultLocale
,
setDoubleBuffered
,
setEnabled
,
setFocusTraversalKeys
,
setFont
,
setForeground
,
setInheritsPopupMenu
,
setInputMap
,
setInputVerifier
,
setMaximumSize
,
setMinimumSize
,
setNextFocusableComponent
,
setOpaque
,
setPreferredSize
,
setRequestFocusEnabled
,
setToolTipText
,
setTransferHandler
,
setUI
,
setVerifyInputWhenFocusTarget
,
setVisible
,
unregisterKeyboardAction
,
update
|
Methods inherited from class java.awt.
Container
|
add
,
add
,
add
,
add
,
add
,
addContainerListener
,
addImpl
,
addPropertyChangeListener
,
addPropertyChangeListener
,
applyComponentOrientation
,
areFocusTraversalKeysSet
,
countComponents
,
deliverEvent
,
doLayout
,
findComponentAt
,
findComponentAt
,
getComponent
,
getComponentAt
,
getComponentAt
,
getComponentCount
,
getComponents
,
getComponentZOrder
,
getContainerListeners
,
getFocusTraversalKeys
,
getFocusTraversalPolicy
,
getLayout
,
getMousePosition
,
insets
,
invalidate
,
isAncestorOf
,
isFocusCycleRoot
,
isFocusCycleRoot
,
isFocusTraversalPolicyProvider
,
isFocusTraversalPolicySet
,
layout
,
list
,
list
,
locate
,
minimumSize
,
paintComponents
,
preferredSize
,
printComponents
,
processContainerEvent
,
processEvent
,
remove
,
remove
,
removeAll
,
removeContainerListener
,
setComponentZOrder
,
setFocusCycleRoot
,
setFocusTraversalPolicy
,
setFocusTraversalPolicyProvider
,
setLayout
,
transferFocusBackward
,
transferFocusDownCycle
,
validate
,
validateTree
|
Methods inherited from class java.awt.
Component
|
action
,
add
,
addComponentListener
,
addFocusListener
,
addHierarchyBoundsListener
,
addHierarchyListener
,
addInputMethodListener
,
addKeyListener
,
addMouseListener
,
addMouseMotionListener
,
addMouseWheelListener
,
bounds
,
checkImage
,
checkImage
,
coalesceEvents
,
contains
,
createImage
,
createImage
,
createVolatileImage
,
createVolatileImage
,
disableEvents
,
dispatchEvent
,
enable
,
enableEvents
,
enableInputMethods
,
firePropertyChange
,
firePropertyChange
,
firePropertyChange
,
firePropertyChange
,
firePropertyChange
,
firePropertyChange
,
getBackground
,
getBounds
,
getColorModel
,
getComponentListeners
,
getComponentOrientation
,
getCursor
,
getDropTarget
,
getFocusCycleRootAncestor
,
getFocusListeners
,
getFocusTraversalKeysEnabled
,
getFont
,
getForeground
,
getGraphicsConfiguration
,
getHierarchyBoundsListeners
,
getHierarchyListeners
,
getIgnoreRepaint
,
getInputContext
,
getInputMethodListeners
,
getInputMethodRequests
,
getKeyListeners
,
getLocale
,
getLocation
,
getLocationOnScreen
,
getMouseListeners
,
getMouseMotionListeners
,
getMousePosition
,
getMouseWheelListeners
,
getName
,
getParent
,
getPeer
,
getPropertyChangeListeners
,
getPropertyChangeListeners
,
getSize
,
getToolkit
,
getTreeLock
,
gotFocus
,
handleEvent
,
hasFocus
,
hide
,
imageUpdate
,
inside
,
isBackgroundSet
,
isCursorSet
,
isDisplayable
,
isEnabled
,
isFocusable
,
isFocusOwner
,
isFocusTraversable
,
isFontSet
,
isForegroundSet
,
isLightweight
,
isMaximumSizeSet
,
isMinimumSizeSet
,
isPreferredSizeSet
,
isShowing
,
isValid
,
isVisible
,
keyDown
,
keyUp
,
list
,
list
,
list
,
location
,
lostFocus
,
mouseDown
,
mouseDrag
,
mouseEnter
,
mouseExit
,
mouseMove
,
mouseUp
,
move
,
nextFocus
,
paintAll
,
postEvent
,
prepareImage
,
prepareImage
,
processComponentEvent
,
processFocusEvent
,
processHierarchyBoundsEvent
,
processHierarchyEvent
,
processInputMethodEvent
,
processMouseWheelEvent
,
remove
,
removeComponentListener
,
removeFocusListener
,
removeHierarchyBoundsListener
,
removeHierarchyListener
,
removeInputMethodListener
,
removeKeyListener
,
removeMouseListener
,
removeMouseMotionListener
,
removeMouseWheelListener
,
removePropertyChangeListener
,
removePropertyChangeListener
,
repaint
,
repaint
,
repaint
,
resize
,
resize
,
setBounds
,
setBounds
,
setComponentOrientation
,
setCursor
,
setDropTarget
,
setFocusable
,
setFocusTraversalKeysEnabled
,
setIgnoreRepaint
,
setLocale
,
setLocation
,
setLocation
,
setName
,
setSize
,
setSize
,
show
,
show
,
size
,
toString
,
transferFocus
,
transferFocusUpCycle
|
VERTICAL
public static final int VERTICAL
-
Indicates a vertical layout of cells, in a single column; the default layout.
Indicates the default layout: one column of cells.
-
Since:
-
1.4
-
See Also:
-
setLayoutOrientation(int)
,
Constant Field Values
VERTICAL_WRAP
public static final int VERTICAL_WRAP
-
Indicates
a
"newspaper style" layout with
the
cells flowing vertically then horizontally.
-
Since:
-
1.4
-
See Also:
-
setLayoutOrientation(int)
,
Constant Field Values
HORIZONTAL_WRAP
public static final int HORIZONTAL_WRAP
-
Indicates
a
"newspaper style"
layout
with
the
cells flowing horizontally then vertically.
-
Since:
-
1.4
-
See Also:
-
setLayoutOrientation(int)
,
Constant Field Values
JList
public JList(ListModel dataModel)
-
Constructs a JList that displays
the
elements
from
in
the specified,
non-null,
non-null
model. All JList constructors delegate to this one.
This constructor registers the list with the ToolTipManager, allowing for tooltips to be provided by the cell renderers.
-
Parameters:
-
dataModel - the
data
model for
the
this
list -
Throws:
-
IllegalArgumentException
- if
the model
dataModel
is null
JList
public JList(Object[] listData)
-
Constructs a JList that displays the elements in the specified array.
This constructor creates a read-only model for the given array, and then delegates to the constructor that takes a ListModel.
This constructor just delegates to the ListModel constructor.
Attempts to pass a null value to this method results in undefined behavior and, most likely, exceptions. The created model references the given array directly. Attempts to modify the array after constructing the list results in undefined behavior.
-
Parameters:
-
listData - the array of Objects to be loaded into the data
model, non-null
model
JList
public JList(Vector<?> listData)
-
Constructs a JList that displays the elements in the specified Vector.
This constructor creates a read-only model for the given Vector, and then delegates to the constructor that takes a ListModel.
This constructor just delegates to the ListModel constructor.
Attempts to pass a null value to this method results in undefined behavior and, most likely, exceptions. The created model references the given Vector directly. Attempts to modify the Vector after constructing the list results in undefined behavior.
-
Parameters:
-
listData - the Vector to be loaded into the data
model, non-null
model
JList
public JList()
-
Constructs a JList with an
empty, read-only,
empty
model.
getUI
public ListUI getUI()
-
Returns the
ListUI, the
look and feel
(L&F)
object that renders this component.
-
-
-
Returns:
-
the ListUI object that renders this component
setUI
public void setUI(ListUI ui)
-
Sets the
ListUI, the
look and feel
(L&F)
object that renders this component.
-
-
-
Parameters:
-
ui - the ListUI
L&F
object -
See Also:
-
UIDefaults.getUI(javax.swing.JComponent)
updateUI
public void updateUI()
-
Resets the ListUI property by setting it to the value provided by the current look and feel. If the current cell renderer was installed by the developer (rather than the look and feel itself), this also causes the cell renderer and its children to be updated, by calling SwingUtilities.updateComponentTreeUI on it.
Resets the UI property with the value from the current look and feel.
-
-
Overrides:
-
updateUI
in class
JComponent
-
-
See Also:
-
UIManager.getUI(javax.swing.JComponent)
,
SwingUtilities.updateComponentTreeUI(java.awt.Component)
getUIClassID
public String getUIClassID()
-
Returns
"ListUI",
the
UIDefaults key
suffix
used to
look up
construct
the name of the
javax.swing.plaf.ListUI class that defines the
look and feel
for
(L&F) class used to render
this component.
-
-
Overrides:
-
getUIClassID
in class
JComponent
-
-
Returns:
-
the string "ListUI"
-
See Also:
-
JComponent.getUIClassID()
,
UIDefaults.getUI(javax.swing.JComponent)
getPrototypeCellValue
public Object getPrototypeCellValue()
-
Returns the "prototypical" cell value -- a value used to calculate a fixed width and height for cells. This can be null if there is no such value.
Returns the cell width of the "prototypical cell" -- a cell used for the calculation of cell widths, because it has the same value as all other list items.
-
-
-
Returns:
-
the value of the prototypeCellValue property
-
See Also:
-
setPrototypeCellValue(java.lang.Object)
setPrototypeCellValue
public void setPrototypeCellValue(Object prototypeCellValue)
-
Sets the prototypeCellValue property, and then (if the new value is non-null), computes the fixedCellWidth and fixedCellHeight properties by requesting the cell renderer component for the given value (and index 0) from the cell renderer, and using that component's preferred size.
Computes the fixedCellWidth and fixedCellHeight properties by configuring the cellRenderer to index equals zero for the specified value and then computing the renderer component's preferred size. These properties are useful when the list is too long to allow JList to compute the width/height of each cell and there is a single cell value that is known to occupy as much space as any of the others.
This method is useful when the list is too long to allow the ListUI to compute the width/height of each cell, and there is a single cell value that is known to occupy as much space as any of the others, a so-called prototype.
Note that we do set the fixedCellWidth and fixedCellHeight properties here but only a prototypeCellValue PropertyChangeEvent is fired.
While all three of the prototypeCellValue, fixedCellHeight, and fixedCellWidth properties may be modified by this method, PropertyChangeEvent notifications are only sent when the prototypeCellValue property changes.
To see an example which sets this property, see the
class description
To see an example which sets this property, see the
class description
above.
The default value of this property is null.
This is a JavaBeans bound property.
-
-
-
Parameters:
-
prototypeCellValue - the value on which to base fixedCellWidth and fixedCellHeight
-
See Also:
-
getPrototypeCellValue()
,
setFixedCellWidth(int)
,
setFixedCellHeight(int)
,
Container.addPropertyChangeListener(java.beans.PropertyChangeListener)
getFixedCellWidth
public int getFixedCellWidth()
-
Returns the value of the fixedCellWidth property.
Returns the fixed cell width value -- the value specified by setting the fixedCellWidth property, rather than that calculated from the list elements.
-
-
-
Returns:
-
the fixed cell width
-
See Also:
-
setFixedCellWidth(int)
setFixedCellWidth
public void setFixedCellWidth(int width)
-
Sets
a fixed value to be used for
the width of every cell in the list. If width is -1, cell widths are computed
in the ListUI
by applying getPreferredSize to the
cell renderer
cellRenderer
component for each list element.
The default value of this property is -1.
This is a JavaBeans bound property.
-
-
-
Parameters:
-
width - the
width to be used
width, in pixels,
for all cells in
the
this
list -
See Also:
-
setPrototypeCellValue(java.lang.Object)
getPrototypeCellValue()
,
setFixedCellWidth(int)
,
Container.addPropertyChangeListener(java.beans.PropertyChangeListener)
getFixedCellHeight
public int getFixedCellHeight()
-
Returns the value of the fixedCellHeight property.
Returns the fixed cell height value -- the value specified by setting the fixedCellHeight property, rather than that calculated from the list elements.
-
-
-
Returns:
-
the fixed cell
height
height, in pixels
-
See Also:
-
setFixedCellHeight(int)
setFixedCellHeight
public void setFixedCellHeight(int height)
-
Sets
a fixed value to be used for
the height of every cell in the list. If height is -1, cell heights are computed
in the ListUI
by applying getPreferredSize to the
cell renderer
cellRenderer
component for each list element.
The default value of this property is -1.
This is a JavaBeans bound property.
-
-
-
Parameters:
-
height -
an integer giving
the
height to be used
height, in pixels,
for
for
all cells in
the
this
list -
See Also:
-
setPrototypeCellValue(java.lang.Object)
getPrototypeCellValue()
,
setFixedCellWidth(int)
,
Container.addPropertyChangeListener(java.beans.PropertyChangeListener)
getCellRenderer
public ListCellRenderer getCellRenderer()
-
Returns the object
responsible for painting
that renders the
list items.
-
-
-
Returns:
-
the value of the cellRenderer property
the ListCellRenderer
-
See Also:
-
setCellRenderer(javax.swing.ListCellRenderer)
setCellRenderer
public void setCellRenderer(ListCellRenderer cellRenderer)
-
Sets the delegate that is used to paint each cell in the list. The job of a cell renderer is discussed in detail in the
class level documentation
.
If the prototypeCellValue property is non-null, setting the cell renderer also causes the fixedCellWidth and fixedCellHeight properties to be re-calculated.
Sets the delegate that's used to paint each cell in the list. If prototypeCellValue was set then the fixedCellWidth and fixedCellHeight properties are set as well.
Only one PropertyChangeEvent is generated however - for the cellRenderer property.
The default value of this property is provided by the ListUI delegate, i.e. by the look and feel implementation.
To see an example which sets the cell renderer, see the
class description
above.
This is a JavaBeans bound property.
-
-
-
Parameters:
-
cellRenderer - the ListCellRenderer that paints list cells
-
See Also:
-
getCellRenderer()
getSelectionForeground
public Color getSelectionForeground()
-
Returns the color used to draw the foreground of selected items. DefaultListCellRenderer uses this color to draw the foreground of items in the selected state, as do the renderers installed by most ListUI implementations.
Returns the selection foreground color.
-
-
-
Returns:
-
the color to draw the foreground of selected items
the Color object for the foreground property
-
See Also:
-
setSelectionForeground(java.awt.Color)
,
DefaultListCellRenderer
setSelectionBackground(java.awt.Color)
setSelectionForeground
public void setSelectionForeground(Color selectionForeground)
-
Sets the color used to draw the foreground of selected items, which cell renderers can use to render text and graphics. DefaultListCellRenderer uses this color to draw the foreground of items in the selected state, as do the renderers installed by most ListUI implementations.
Sets the foreground color for selected cells. Cell renderers can use this color to render text and graphics for selected cells.
The default value of this property is defined by the look and feel implementation.
This is a JavaBeans bound property.
-
-
-
Parameters:
-
selectionForeground - the Color to use in the foreground for selected list items
-
See Also:
-
getSelectionForeground()
,
setSelectionBackground(java.awt.Color)
,
JComponent.setForeground(java.awt.Color)
,
JComponent.setBackground(java.awt.Color)
,
JComponent.setFont(java.awt.Font)
,
DefaultListCellRenderer
getSelectionBackground
public Color getSelectionBackground()
-
Returns the color used to draw the background of selected items. DefaultListCellRenderer uses this color to draw the background of items in the selected state, as do the renderers installed by most ListUI implementations.
Returns the background color for selected cells.
-
-
-
Returns:
-
the
color to draw
Color used for
the background of selected
list
items -
See Also:
-
setSelectionBackground(java.awt.Color)
,
DefaultListCellRenderer
setSelectionForeground(java.awt.Color)
setSelectionBackground
public void setSelectionBackground(Color selectionBackground)
-
Sets the color used to draw the background of selected items, which cell renderers can use fill selected cells. DefaultListCellRenderer uses this color to fill the background of items in the selected state, as do the renderers installed by most ListUI implementations.
Sets the background color for selected cells. Cell renderers can use this color to the fill selected cells.
The default value of this property is defined by the look and feel implementation.
This is a JavaBeans bound property.
-
-
-
Parameters:
-
selectionBackground - the Color to use for the background of selected cells
-
See Also:
-
getSelectionBackground()
,
setSelectionForeground(java.awt.Color)
,
JComponent.setForeground(java.awt.Color)
,
JComponent.setBackground(java.awt.Color)
,
JComponent.setFont(java.awt.Font)
,
DefaultListCellRenderer
getVisibleRowCount
public int getVisibleRowCount()
-
Returns the value of the visibleRowCount property. See the documentation for
setVisibleRowCount(int)
for details on how to interpret this value.
Returns the preferred number of visible rows.
-
-
-
Returns:
-
the value of the visibleRowCount property.
an integer indicating the preferred number of rows to display without using a scroll bar
-
See Also:
-
setVisibleRowCount(int)
setVisibleRowCount
public void setVisibleRowCount(int visibleRowCount)
-
Sets the visibleRowCount property, which has different meanings depending on the layout orientation: For a VERTICAL layout orientation, this sets the preferred number of rows to display without requiring scrolling; for other orientations, it affects the wrapping of cells.
Sets the preferred number of rows in the list that can be displayed without a scrollbar, as determined by the nearest JViewport ancestor, if any. The value of this property only affects the value of the JList's preferredScrollableViewportSize.
In VERTICAL orientation:
Setting this property affects the return value of the
getPreferredScrollableViewportSize()
method, which is used to calculate the preferred size of an enclosing viewport. See that method's documentation for more details.
In HORIZONTAL_WRAP and VERTICAL_WRAP orientations:
This affects how cells are wrapped. See the documentation of
setLayoutOrientation(int)
for more details.
The default value of this property is 8.
Calling this method with a negative value results in the property being set to 0.
This is a JavaBeans bound property.
-
-
-
Parameters:
-
visibleRowCount - an integer specifying the preferred number of
visible
rows
to display without requiring scrolling
-
See Also:
-
getVisibleRowCount()
,
getPreferredScrollableViewportSize()
,
setLayoutOrientation(int)
,
JComponent.getVisibleRect()
,
JViewport
getLayoutOrientation
public int getLayoutOrientation()
-
Returns
the layout orientation property for the list: VERTICAL
JList.VERTICAL
if the layout is a single column of cells,
VERTICAL_WRAP
or JList.VERTICAL_WRAP
if the layout is "newspaper style" with the content flowing vertically then
horizontally,
horizontally
or
HORIZONTAL_WRAP
JList.HORIZONTAL_WRAP
if the layout is "newspaper style" with the content flowing horizontally then vertically.
-
-
-
Returns:
-
the value of the layoutOrientation property
-
Since:
-
1.4
-
See Also:
-
setLayoutOrientation(int)
setLayoutOrientation
public void setLayoutOrientation(int layoutOrientation)
-
Defines the way list cells are layed out. Consider a JList with
five cells. Cells
four cells, this
can be layed out in one of the following ways:
VERTICAL: 0
1
2
3
4
HORIZONTAL_WRAP: 0 1 2
3 4
VERTICAL_WRAP: 0 3
1 4
2
![](../../diffpics/oold.gif)
0
1
2
3
![](../../diffpics/oold.gif)
0 1
2 3
![](../../diffpics/oold.gif)
0 2
1 3
A description of these layouts follows:
These correspond to the following values:
The default value of this property is JList.VERTICAL.
The default value of this property is VERTICAL.
This will throw an IllegalArgumentException if layoutOrientation is not one of JList.HORIZONTAL_WRAP or JList.VERTICAL or JList.VERTICAL_WRAP
-
-
-
Parameters:
-
layoutOrientation - the new layout orientation, one of: VERTICAL, HORIZONTAL_WRAP or VERTICAL_WRAP
layoutOrientation - New orientation, one of JList.HORIZONTAL_WRAP, JList.VERTICAL or JList.VERTICAL_WRAP.
-
Throws:
-
IllegalArgumentException
- if layoutOrientation isn't one of the allowable values
-
Since:
-
1.4
-
See Also:
-
getLayoutOrientation()
,
setVisibleRowCount(int)
,
getScrollableTracksViewportHeight()
,
getScrollableTracksViewportWidth()
getFirstVisibleIndex
public int getFirstVisibleIndex()
-
Returns the
smallest list
index
that
of the first visible cell. The cell considered to be "first" depends on the list's componentOrientation property. If the orientation
is
currently visible. In a left-to-right componentOrientation,
horizontal left-to-right, then
the first visible cell is
found closest to
in
the list's upper-left corner.
In right-to-left orientation, it
If the orientation
is
found closest to
horizontal right-to-left, then
the
first visible cell is in the list's
upper-right corner. If nothing is visible or the list is empty,
a
-1 is returned. Note that the returned cell may only be partially visible.
-
-
-
Returns:
-
the index of the first visible cell
-
See Also:
-
getLastVisibleIndex()
,
JComponent.getVisibleRect()
getLastVisibleIndex
public int getLastVisibleIndex()
-
Returns the largest list index that is currently visible. If nothing is visible or the list is empty, -1 is returned.
Returns the index of the last visible cell. The cell considered to be "last" depends on the list's componentOrientation property. If the orientation is horizontal left-to-right, then the last visible cell is in the JList's lower-right corner. If the orientation is horizontal right-to-left, then the last visible cell is in the JList's lower-left corner. If nothing is visible or the list is empty, a -1 is returned.
Note that the returned cell may only be partially visible.
-
-
-
Returns:
-
the index of the last visible cell
-
See Also:
-
getFirstVisibleIndex()
,
JComponent.getVisibleRect()
ensureIndexIsVisible
public void ensureIndexIsVisible(int index)
-
Scrolls the
list within an enclosing
viewport to make the specified cell completely visible.
This calls scrollRectToVisible with the bounds of the specified cell. For
Note, for
this method to work, the JList must be
displayed
within a JViewport.
If the given index is outside the list's range of cells, this method results in nothing.
-
-
-
Parameters:
-
index - the index of the cell to make visible
-
See Also:
-
JComponent.scrollRectToVisible(java.awt.Rectangle)
,
JComponent.getVisibleRect()
setDragEnabled
public void setDragEnabled(boolean b)
-
Turns on or off automatic drag handling. In order to enable automatic drag handling, this property should be set to true, and the list's TransferHandler needs to be non-null.
Sets the dragEnabled property, which must be true to enable automatic drag handling (the first part of drag and drop) on this component. The transferHandler property needs to be set to a non-null value for the drag to do anything.
The default value of the dragEnabled property is false.
The job of honoring this property, and recognizing a user drag gesture, lies with the look and feel implementation, and in particular, the list's ListUI.
When automatic drag handling is enabled, most look and feels
(including those that subclass BasicLookAndFeel)
begin a
drag and drop
drag-and-drop
operation whenever the user presses the mouse button over an item and then moves the mouse a few pixels. Setting this property to true can therefore have a subtle effect on how selections behave.
If a look and feel is used that ignores this property, you can still begin a drag and drop operation by calling exportAsDrag on the list's TransferHandler.
Some look and feels might not support automatic drag and drop; they will ignore this property. You can work around such look and feels by modifying the component to directly call the exportAsDrag method of a TransferHandler.
-
-
-
Parameters:
-
b - whether or not to enable automatic drag handling
b - the value to set the dragEnabled property to
-
Throws:
-
HeadlessException
- if b is true and GraphicsEnvironment.isHeadless() returns true
-
Since:
-
1.4
-
See Also:
-
GraphicsEnvironment.isHeadless()
,
getDragEnabled()
,
JComponent.setTransferHandler(javax.swing.TransferHandler)
,
TransferHandler
getDragEnabled
public boolean getDragEnabled()
-
Returns whether or not automatic drag handling is enabled.
Gets the dragEnabled property.
-
-
-
Returns:
-
the value of the dragEnabled property
-
Since:
-
1.4
-
See Also:
-
setDragEnabled(boolean)
setDropMode
public final void setDropMode(DropMode dropMode)
-
Sets
Set
the drop mode for this component. For backward compatibility, the default for this property is DropMode.USE_SELECTION. Usage of one of the other modes is recommended, however, for an improved user experience. DropMode.ON, for instance, offers similar behavior of showing items as selected, but does so without affecting the actual selection in the list.
JList supports the following drop modes:
-
DropMode.USE_SELECTION
-
DropMode.ON
-
DropMode.INSERT
-
DropMode.ON_OR_INSERT
The drop mode is only meaningful if this component has a TransferHandler that accepts drops.
-
-
-
Parameters:
-
dropMode - the drop mode to use
-
Throws:
-
IllegalArgumentException
- if the drop mode is unsupported or null
-
Since:
-
1.6
-
See Also:
-
getDropMode()
,
getDropLocation()
,
JComponent.setTransferHandler(javax.swing.TransferHandler)
,
TransferHandler
getDropMode
public final DropMode getDropMode()
-
Returns the drop mode for this component.
-
-
-
Returns:
-
the drop mode for this component
-
Since:
-
1.6
-
See Also:
-
setDropMode(javax.swing.DropMode)
getDropLocation
public final JList.DropLocation getDropLocation()
-
Returns the location that this component should visually indicate as the drop location during a DnD operation over the
component, or
component. This will be
null if
there is
no
DnD operation over the component or if the component's TransferHandler has indicated that it cannot accept the current transfer (and has not specified that the drop
location
is to currently
be
shown.
indicated anyway).
This method is not meant for querying the drop location from a
TransferHandler,
TransferHandler
as the drop location is only set after the TransferHandler's canImport
has
or shouldIndicateAnyway methods have
returned
and has allowed for the location to be shown.
true.
When this property changes, a property change event with name "dropLocation" is fired by the component.
By default, responsibility for listening for changes to this property and indicating the drop location visually lies with the list's ListUI, which may paint it directly and/or install a cell renderer to do so. Developers wishing to implement custom drop location painting and/or replace the default cell renderer, may need to honor this property.
-
-
-
Returns:
-
the drop location
-
Since:
-
1.6
-
See Also:
-
setDropMode(javax.swing.DropMode)
,
TransferHandler.canImport(TransferHandler.TransferSupport)
TransferHandler.TransferInfo
,
TransferHandler.canImport(TransferHandler.TransferInfo)
, TransferHandler#shouldIndicateAnyway(TransferHandler.TransferInfo)
getNextMatch
public int getNextMatch(String prefix,
int startIndex,
Position.Bias bias)
-
Returns the next list element
whose toString value
that
starts with
the given
a
prefix.
-
-
-
Parameters:
-
prefix - the string to test for a match
-
startIndex - the index for starting the search
-
bias - the search direction, either Position.Bias.Forward or Position.Bias.Backward.
-
Returns:
-
the index of the next list element that starts with the prefix; otherwise -1
-
Throws:
-
IllegalArgumentException
- if prefix is null or startIndex is out of bounds
-
Since:
-
1.4
getToolTipText
public String getToolTipText(MouseEvent event)
-
Returns the tooltip text to be used for the given event. This overrides JComponent's getToolTipText to first check the cell renderer component for the cell over which the event occurred, returning its tooltip text, if any. This implementation allows you to specify tooltip text on the cell level, by using setToolTipText on your cell renderer component.
Overrides JComponent's getToolTipText method in order to allow the renderer's tips to be used if it has text set.
Note:
For JList to properly display
the
tooltips of its renderers
in this manner,
JList must be a registered component with the ToolTipManager. This
registration
is done automatically in the
constructor. However,
constructor, but
if at a later point JList is
unregistered, by way of a call to setToolTipText(null),
told setToolTipText(null) it will unregister the list component, and no
tips from
the
renderers will
no longer display.
display anymore.
-
-
Overrides:
-
getToolTipText
in class
JComponent
-
-
Parameters:
-
event - the MouseEvent to fetch the tooltip text for
-
See Also:
-
JComponent.setToolTipText(java.lang.String)
JComponent.getToolTipText()
,
JComponent.getToolTipText()
locationToIndex
public int locationToIndex(Point location)
-
Returns the cell index closest to the given location in the list's coordinate system. To determine if the cell actually contains the specified location, compare the point against the cell's bounds, as provided by getCellBounds. This method returns -1 if the model is empty
Convert a point in JList coordinates to the closest index of the cell at that location. To determine if the cell actually contains the specified location use a combination of this method and getCellBounds. Returns -1 if the model is empty.
This is a cover method that delegates to the method of the same name in the list's ListUI. It returns -1 if the list has no ListUI.
-
-
-
Parameters:
-
location - the coordinates of the
point
cell, relative to JList
-
Returns:
-
an integer --
the
index of the
cell
index closest to
at
the given location, or
-1
-1.
indexToLocation
public Point indexToLocation(int index)
-
Returns the origin of the specified item in
the list's coordinate system. This method returns
JList coordinates. Returns
null if
the
index isn't valid.
This is a cover method that delegates to the method of the same name in the list's ListUI. It returns null if the list has no ListUI.
-
-
-
Parameters:
-
index - the
index of the JList
cell
index
-
Returns:
-
the origin of the
cell, or null
index'th cell
getCellBounds
public Rectangle getCellBounds(int index0,
int index1)
-
Returns the bounding rectangle, in the list's coordinate system, for the range of cells specified by the two indices. These indices can be supplied in any order.
Returns the bounds of the specified range of items in JList coordinates. Returns null if index isn't valid.
If the smaller index is outside the list's range of cells, this method returns null. If the smaller index is valid, but the larger index is outside the list's range, the bounds of just the first index is returned. Otherwise, the bounds of the valid range is returned.
This is a cover method that delegates to the method of the same name in the list's ListUI. It returns null if the list has no ListUI.
-
-
-
Parameters:
-
index0 - the
index of the
first
index
JList cell
in the range -
index1 - the
second
index
of the last JList cell
in the range -
Returns:
-
the bounding rectangle for the range of cells, or null
the bounds of the indexed cells in pixels
getModel
public ListModel getModel()
-
Returns the data model that holds the list of items displayed by the JList component.
-
-
-
Returns:
-
the ListModel that provides the displayed list of items
-
See Also:
-
setModel(javax.swing.ListModel)
setModel
public void setModel(ListModel model)
-
Sets the model that represents the contents or "value" of the
list, notifies property change listeners,
list
and
then
clears the
list's selection.
list selection after notifying PropertyChangeListeners.
This is a JavaBeans bound property.
-
-
-
Parameters:
-
model - the ListModel that provides the list of items for display
-
Throws:
-
IllegalArgumentException
- if model is null
-
See Also:
-
getModel()
,
clearSelection()
setListData
public void setListData(Object[] listData)
-
Constructs a
read-only
ListModel from an array of
objects,
objects
and
calls
then applies
setModel
with this model.
to it.
Attempts to pass a null value to this method results in undefined behavior and, most likely, exceptions. The created model references the given array directly. Attempts to modify the array after invoking this method results in undefined behavior.
-
-
-
Parameters:
-
listData - an array of Objects containing the items to display in the list
-
See Also:
-
setModel(javax.swing.ListModel)
setListData
public void setListData(Vector<?> listData)
-
Constructs a
read-only
ListModel from a Vector and
calls
then applies
setModel
with this model.
to it.
Attempts to pass a null value to this method results in undefined behavior and, most likely, exceptions. The created model references the given Vector directly. Attempts to modify the Vector after invoking this method results in undefined behavior.
-
-
-
Parameters:
-
listData - a Vector containing the items to display in the list
-
See Also:
-
setModel(javax.swing.ListModel)
createSelectionModel
protected ListSelectionModel createSelectionModel()
-
Returns an instance of
DefaultListSelectionModel; called during construction
DefaultListSelectionModel. This method is used by the constructor
to initialize the
list's selection model
selectionModel
property.
-
-
-
Returns:
-
a DefaultListSelecitonModel, used to initialize the list's selection model property during construction
the ListSelectionModel used by this JList.
-
See Also:
-
setSelectionModel(javax.swing.ListSelectionModel)
,
DefaultListSelectionModel
getSelectionModel
public ListSelectionModel getSelectionModel()
-
Returns the current selection model. The selection model maintains the selection state of the list. See the class level documentation for more details.
Returns the value of the current selection model. The selection model handles the task of making single selections, selections of contiguous ranges, and non-contiguous selections.
-
-
-
Returns:
-
the ListSelectionModel that
maintains the list's
implements list
selections -
See Also:
-
setSelectionModel(javax.swing.ListSelectionModel)
,
ListSelectionModel
fireSelectionValueChanged
protected void fireSelectionValueChanged(int firstIndex,
int lastIndex,
boolean isAdjusting)
-
Notifies ListSelectionListeners added directly to the list of selection changes made to the selection model. JList listens for changes made to the selection in the selection model, and forwards notification to listeners added to the list directly, by calling this method.
Notifies JList ListSelectionListeners that the selection model has changed. It's used to forward ListSelectionEvents from the selectionModel to the ListSelectionListeners added directly to the JList.
This method constructs a ListSelectionEvent with this list as the source, and the specified arguments, and sends it to the registered ListSelectionListeners.
-
-
-
Parameters:
-
firstIndex - the first
selected
index
in the range, <= lastIndex
-
lastIndex - the last
selected
index
in the range, >= firstIndex
-
isAdjusting - whether or not this is one in a series of multiple events, where changes are still being made
isAdjusting - true if multiple changes are being made
-
See Also:
-
addListSelectionListener(javax.swing.event.ListSelectionListener)
,
removeListSelectionListener(javax.swing.event.ListSelectionListener)
,
ListSelectionEvent
,
EventListenerList
addListSelectionListener
public void addListSelectionListener(ListSelectionListener listener)
-
Adds a listener to the list, to be notified each time a change to the selection occurs; the preferred way of listening for selection state changes. JList takes care of listening for selection state changes in the selection model, and notifies the given listener of each change. ListSelectionEvents sent to the listener have a source property set to this list.
Adds a listener to the list that's notified each time a change to the selection occurs. Listeners added directly to the JList will have their ListSelectionEvent.getSource() == this JList (instead of the ListSelectionModel).
-
-
-
Parameters:
-
listener - the ListSelectionListener to add
-
See Also:
-
getSelectionModel()
,
getListSelectionListeners()
removeListSelectionListener
public void removeListSelectionListener(ListSelectionListener listener)
-
Removes a selection listener from the list.
Removes a listener from the list that's notified each time a change to the selection occurs.
-
-
-
Parameters:
-
listener - the ListSelectionListener to remove
-
See Also:
-
addListSelectionListener(javax.swing.event.ListSelectionListener)
,
getSelectionModel()
getListSelectionListeners
public ListSelectionListener[] getListSelectionListeners()
-
Returns an array of all the ListSelectionListeners added to this JList
by way of addListSelectionListener.
with addListSelectionListener().
-
-
-
Returns:
-
all of the ListSelectionListeners
on this list,
added
or an empty array if no listeners have been added -
Since:
-
1.4
-
See Also:
-
addListSelectionListener(javax.swing.event.ListSelectionListener)
setSelectionModel
public void setSelectionModel(ListSelectionModel selectionModel)
-
Sets the selectionModel for the list to a non-null ListSelectionModel implementation. The selection model handles the task of making single selections, selections of contiguous ranges, and non-contiguous selections.
This is a JavaBeans bound property.
-
-
-
Parameters:
-
selectionModel - the ListSelectionModel that implements the selections
-
Throws:
-
IllegalArgumentException
- if selectionModel is null
-
See Also:
-
getSelectionModel()
setSelectionMode
public void setSelectionMode(int selectionMode)
-
Sets the selection mode for the list. This is a cover method that sets the selection mode directly on the selection model.
The following list describes the accepted selection modes:
Determines whether single-item or multiple-item selections are allowed. The following selectionMode values are allowed:
-
ListSelectionModel.SINGLE_SELECTION
-
Only one list index can be selected at a time. In this
mode,
mode the
setSelectionInterval and addSelectionInterval
methods
are equivalent,
both replacing
and only
the
current selection with the
second
index
represented by the second
argument
(the "lead").
is used.
-
ListSelectionModel.SINGLE_INTERVAL_SELECTION
- Only one
One
contiguous
index
interval can be selected at a time. In this
mode, addSelectionInterval behaves like
mode
setSelectionInterval
(replacing the current selection}, unless the given interval is immediately adjacent to or overlaps the existing selection,
and
can be used to grow the selection.
addSelectionInterval are equivalent.
-
ListSelectionModel.MULTIPLE_INTERVAL_SELECTION
-
In this mode, there's no restriction on what can be selected. This
mode
is the default.
-
-
-
Parameters:
-
selectionMode - the selection mode
selectionMode - an integer specifying the type of selections that are permissible
-
Throws:
-
IllegalArgumentException
- if the selection mode isn't one of those allowed
-
See Also:
-
getSelectionMode()
getSelectionMode
public int getSelectionMode()
-
Returns the current selection mode for the list. This is a cover method that delegates to the method of the same name on the list's selection model.
Returns whether single-item or multiple-item selections are allowed.
-
-
-
Returns:
-
the current selection mode
the value of the selectionMode property
-
See Also:
-
setSelectionMode(int)
getAnchorSelectionIndex
public int getAnchorSelectionIndex()
-
Returns the anchor selection index. This is a cover method that delegates to the method of the same name on the list's selection model.
Returns the first index argument from the most recent addSelectionModel or setSelectionInterval call. This is a convenience method that just delegates to the selectionModel.
-
-
-
Returns:
-
the anchor selection index
the index that most recently anchored an interval selection
-
See Also:
-
ListSelectionModel.getAnchorSelectionIndex()
,
addSelectionInterval(int, int)
,
setSelectionInterval(int, int)
,
addListSelectionListener(javax.swing.event.ListSelectionListener)
getLeadSelectionIndex
public int getLeadSelectionIndex()
-
Returns the lead selection index. This is a cover method that delegates to the method of the same name on the list's selection model.
Returns the second index argument from the most recent addSelectionInterval or setSelectionInterval call. This is a convenience method that just delegates to the selectionModel.
-
-
-
Returns:
-
the lead selection index
the index that most recently ended a interval selection
-
See Also:
-
ListSelectionModel.getLeadSelectionIndex()
,
addSelectionInterval(int, int)
,
setSelectionInterval(int, int)
,
addListSelectionListener(javax.swing.event.ListSelectionListener)
getMinSelectionIndex
public int getMinSelectionIndex()
-
Returns the smallest selected cell
index, or -1 if the selection is empty.
index.
This is a
cover
convenience
method that
just
delegates to the
method of the same name on the list's selection model.
selectionModel.
-
-
-
Returns:
-
the smallest selected cell
index, or -1
index
-
See Also:
-
ListSelectionModel.getMinSelectionIndex()
,
addListSelectionListener(javax.swing.event.ListSelectionListener)
getMaxSelectionIndex
public int getMaxSelectionIndex()
-
Returns the largest selected cell
index, or -1 if the selection is empty.
index.
This is a
cover
convenience
method that
just
delegates to the
method of the same name on the list's selection model.
selectionModel.
-
-
-
Returns:
-
the largest selected cell index
-
See Also:
-
ListSelectionModel.getMaxSelectionIndex()
,
addListSelectionListener(javax.swing.event.ListSelectionListener)
isSelectedIndex
public boolean isSelectedIndex(int index)
-
Returns true if the specified index is
selected, else false.
selected.
This is a
cover
convenience
method that
just
delegates to the
method of the same name on the list's selection model.
selectionModel.
-
-
-
Parameters:
-
index - index to be queried for selection state
-
Returns:
-
true if the specified index is
selected, else false
selected
-
See Also:
-
ListSelectionModel.isSelectedIndex(int)
,
setSelectedIndex(int)
,
addListSelectionListener(javax.swing.event.ListSelectionListener)
isSelectionEmpty
public boolean isSelectionEmpty()
-
Returns true if nothing is
selected, else false.
selected.
This is a
cover
convenience
method that
just
delegates to the
method of the same name on the list's selection model.
selectionModel.
-
-
-
Returns:
-
true if nothing is
selected, else false
selected
-
See Also:
-
ListSelectionModel.isSelectionEmpty()
,
clearSelection()
,
addListSelectionListener(javax.swing.event.ListSelectionListener)
clearSelection
public void clearSelection()
-
Clears the
selection;
selection -
after calling this
method,
method
isSelectionEmpty will return true. This is a
cover
convenience
method that
just
delegates to the
method of the same name on the list's selection model.
selectionModel.
-
-
-
See Also:
-
ListSelectionModel.clearSelection()
,
isSelectionEmpty()
,
addListSelectionListener(javax.swing.event.ListSelectionListener)
setSelectionInterval
public void setSelectionInterval(int anchor,
int lead)
-
Selects the specified interval.
Both anchor and lead indices are included. anchor doesn't have to be less than or equal to lead. This is a cover method that delegates to the method of the same name on the list's selection model.
Both the anchor and lead indices are included. It's not necessary for anchor to be less than lead. This is a convenience method that just delegates to the selectionModel. The DefaultListSelectionModel implementation will do nothing if either anchor or lead are -1. If anchor or lead are less than -1, IndexOutOfBoundsException is thrown.
Refer to the documentation of the selection model class being used for details on how values less than 0 are handled.
-
-
-
Parameters:
-
anchor - the first index to select
-
lead - the last index to select
-
Throws:
-
IndexOutOfBoundsException
- if either anchor or lead are less than -1
-
See Also:
-
ListSelectionModel.setSelectionInterval(int, int)
,
DefaultListSelectionModel.setSelectionInterval(int, int)
,
createSelectionModel()
,
addSelectionInterval(int, int)
,
removeSelectionInterval(int, int)
,
addListSelectionListener(javax.swing.event.ListSelectionListener)
addSelectionInterval
public void addSelectionInterval(int anchor,
int lead)
-
Sets the selection to be the union of the specified interval with current selection. Both the anchor and lead indices are included.
anchor doesn't have to be less than or equal to lead. This is a cover method that delegates to the method of the same name on the list's selection model.
It's not necessary for anchor to be less than lead. This is a convenience method that just delegates to the selectionModel. The DefaultListSelectionModel implementation will do nothing if either anchor or lead are -1. If anchor or lead are less than -1, IndexOutOfBoundsException is thrown.
Refer to the documentation of the selection model class being used for details on how values less than 0 are handled.
-
-
-
Parameters:
-
anchor - the first index to add to the selection
-
lead - the last index to add to the selection
-
Throws:
-
IndexOutOfBoundsException
- if either anchor or lead are less than -1
-
See Also:
-
ListSelectionModel.addSelectionInterval(int, int)
,
DefaultListSelectionModel.addSelectionInterval(int, int)
,
createSelectionModel()
,
setSelectionInterval(int, int)
,
removeSelectionInterval(int, int)
,
addListSelectionListener(javax.swing.event.ListSelectionListener)
removeSelectionInterval
public void removeSelectionInterval(int index0,
int index1)
-
Sets the selection to be the set difference of the specified interval and the current selection. Both the index0 and index1 indices are removed.
index0 doesn't have to be less than or equal to index1. This is a cover method that delegates to the method of the same name on the list's selection model.
It's not necessary for index0 to be less than index1. This is a convenience method that just delegates to the selectionModel. The DefaultListSelectionModel implementation will do nothing if either index0 or index1 are -1. If index0 or index1 are less than -1, IndexOutOfBoundsException is thrown.
Refer to the documentation of the selection model class being used for details on how values less than 0 are handled.
-
-
-
Parameters:
-
index0 - the first index to remove from the selection
-
index1 - the last index to remove from the selection
-
Throws:
-
IndexOutOfBoundsException
- if either index0 or index1 are less than -1
-
See Also:
-
ListSelectionModel.removeSelectionInterval(int, int)
,
DefaultListSelectionModel.removeSelectionInterval(int, int)
,
createSelectionModel()
,
setSelectionInterval(int, int)
,
addSelectionInterval(int, int)
,
addListSelectionListener(javax.swing.event.ListSelectionListener)
setValueIsAdjusting
public void setValueIsAdjusting(boolean b)
-
Sets the selection model's valueIsAdjusting property. When true, upcoming changes to selection should be considered part of a single change. This property is used internally and developers typically need not call this method. For example, when the model is being updated in response to a user drag, the value of the property is set to true when the drag is initiated and set to false when the drag is finished. This allows listeners to update only when a change has been finalized, rather than handling all of the intermediate values.
Sets the data model's isAdjusting property to true, so that a single event will be generated when all of the selection events have finished (for example, when the mouse is being dragged over the list in selection mode).
You may want to use this directly if making a series of changes that should be considered part of a single change.
This is a cover method that delegates to the method of the same name on the list's selection model. See the documentation for
ListSelectionModel.setValueIsAdjusting(boolean)
for more details.
-
-
-
Parameters:
-
b - the
new
boolean
value for the property
value
-
See Also:
-
ListSelectionModel.setValueIsAdjusting(boolean)
,
ListSelectionEvent.getValueIsAdjusting()
,
getValueIsAdjusting()
getValueIsAdjusting
public boolean getValueIsAdjusting()
-
Returns the value of the
selection
data
model's isAdjusting property.
This value is true if multiple changes are being made.
This is a cover method that delegates to the method of the same name on the list's selection model.
-
-
-
Returns:
-
the value of the selection model's isAdjusting property.
true if multiple selection-changes are occurring, as when the mouse is being dragged over the list
-
See Also:
-
setValueIsAdjusting(boolean)
ListSelectionModel.getValueIsAdjusting()
,
ListSelectionModel.getValueIsAdjusting()
getSelectedIndices
public int[] getSelectedIndices()
-
Returns an array of all of the selected
indices,
indices
in increasing order.
-
-
-
Returns:
-
all of the selected indices, in increasing
order, or an empty array if nothing is selected
order
-
See Also:
-
removeSelectionInterval(int, int)
,
addListSelectionListener(javax.swing.event.ListSelectionListener)
setSelectedIndex
public void setSelectedIndex(int index)
-
Selects a single cell.
Does nothing if the given index is greater than or equal to the model size. This is a convenience method that uses setSelectionInterval on the selection model. Refer to the documentation for the selection model class being used for details on how values less than 0 are handled.
-
-
-
Parameters:
-
index - the index of the
one
cell to select -
See Also:
-
ListSelectionModel.setSelectionInterval(int, int)
,
isSelectedIndex(int)
,
addListSelectionListener(javax.swing.event.ListSelectionListener)
setSelectedIndices
public void setSelectedIndices(int[] indices)
-
Changes the selection to be the set of indices specified by the given array. Indices greater than or equal to the model size are ignored. This is a convenience method that clears the selection and then uses addSelectionInterval on the selection model to add the indices. Refer to the documentation of the selection model class being used for details on how values less than 0 are handled.
Selects a set of cells.
-
-
-
Parameters:
-
indices - an array of the indices of the cells to
select, non-null
select
-
Throws:
-
NullPointerException
- if the given array is null
-
See Also:
-
ListSelectionModel.addSelectionInterval(int, int)
,
isSelectedIndex(int)
,
addListSelectionListener(javax.swing.event.ListSelectionListener)
getSelectedValues
public Object[] getSelectedValues()
-
Returns an array of all the selected values, in increasing order based on their indices in the list.
Returns an array of the values for the selected cells. The returned values are sorted in increasing index order.
-
-
-
Returns:
-
the selected
values,
values
or an empty
array
list
if nothing is selected -
See Also:
-
isSelectedIndex(int)
,
getModel()
,
addListSelectionListener(javax.swing.event.ListSelectionListener)
getSelectedIndex
public int getSelectedIndex()
-
Returns the smallest selected cell index;
the selection
when only a single item is selected in the list. When multiple items are selected, it is simply the smallest selected index. Returns -1 if there is no selection.
Returns the first selected index; returns -1 if there is no selected item.
This method is a cover that delegates to getMinSelectionIndex.
-
-
-
Returns:
-
the smallest selected cell index
the value of getMinSelectionIndex
-
See Also:
-
getMinSelectionIndex()
,
addListSelectionListener(javax.swing.event.ListSelectionListener)
getSelectedValue
public Object getSelectedValue()
-
Returns the value for the smallest selected cell index;
the selected value
when only a single item is selected in the list. When multiple items are selected, it is simply the value for the smallest selected index. Returns null if there is no selection.
Returns the first selected value, or null if the selection is empty.
This is a convenience method that simply returns the model value for getMinSelectionIndex.
-
-
-
Returns:
-
the first selected value
-
See Also:
-
getMinSelectionIndex()
,
getModel()
,
addListSelectionListener(javax.swing.event.ListSelectionListener)
setSelectedValue
public void setSelectedValue(Object anObject,
boolean shouldScroll)
-
Selects the specified object from the list.
-
-
-
Parameters:
-
anObject - the object to select
-
shouldScroll - true if the list should scroll to display the selected object, if one exists; otherwise false
getPreferredScrollableViewportSize
public Dimension getPreferredScrollableViewportSize()
-
Computes the size of viewport needed to display visibleRowCount rows. The value returned by this method depends on the layout orientation:
Computes the size of the viewport needed to display visibleRowCount rows. This is trivial if fixedCellWidth and fixedCellHeight were specified. Note that they can be specified implicitly with the prototypeCellValue property. If fixedCellWidth wasn't specified, it's computed by finding the widest list element. If fixedCellHeight wasn't specified then we resort to heuristics:
-
If the model isn't empty we just multiply the height of the first row by visibleRowCount.
-
If the model is empty, (JList.getModel().getSize() == 0), then we just allocate 16 pixels per visible row, and 256 pixels for the width (unless fixedCellWidth was set), and hope for the best.
If the layout orientation is not VERTICAL, than this will return the value from getPreferredSize. The current ListUI is expected to override getPreferredSize to return an appropriate value.
VERTICAL:
This is trivial if both fixedCellWidth and fixedCellHeight have been set (either explicitly or by specifying a prototype cell value). The width is simply the fixedCellWidth plus the list's horizontal insets. The height is the fixedCellHeight multiplied by the visibleRowCount, plus the list's vertical insets.
If either fixedCellWidth or fixedCellHeight haven't been specified, heuristics are used. If the model is empty, the width is the fixedCellWidth, if greater than 0, or a hard-coded value of 256. The height is the fixedCellHeight multiplied by visibleRowCount, if fixedCellHeight is greater than 0, otherwise it is a hard-coded value of 16 multiplied by visibleRowCount.
If the model isn't empty, the width is the preferred size's width, typically the width of the widest list element. The height is the fixedCellHeight multiplied by the visibleRowCount, plus the list's vertical insets.
VERTICAL_WRAP or HORIZONTAL_WRAP:
This method simply returns the value from getPreferredSize. The list's ListUI is expected to override getPreferredSize to return an appropriate value.
-
-
Specified by:
-
getPreferredScrollableViewportSize
in interface
Scrollable
-
-
Returns:
-
a dimension containing the size of the viewport needed to display visibleRowCount rows
-
See Also:
-
getPreferredScrollableViewportSize()
,
setPrototypeCellValue(java.lang.Object)
getScrollableUnitIncrement
public int getScrollableUnitIncrement(Rectangle visibleRect,
int orientation,
int direction)
-
Returns the distance to scroll to expose the next or previous row (for vertical scrolling) or column (for horizontal scrolling).
For horizontal
scrolling,
scrolling
if the
layout
list is layed out vertically (the
orientation is
VERTICAL, then
VERTICAL) than
the
list's
lists
font size
or 1
is returned
(or 1
if the font is
null).
null is used.
-
-
Specified by:
-
getScrollableUnitIncrement
in interface
Scrollable
-
-
Parameters:
-
visibleRect - the
view area
visible
within the viewport
rectangle
-
orientation -
SwingConstants.HORIZONTAL
HORIZONTAL
or
SwingConstants.VERTICAL
VERTICAL
-
direction - less or equal to zero to scroll up/back, greater than zero for down/forward
direction - if
<= 0, then scroll UP; if >
0, then scroll DOWN
-
Returns:
-
the "unit" increment for scrolling in the specified direction; always positive
the distance, in pixels, to scroll to expose the next or previous unit
-
Throws:
-
IllegalArgumentException
- if visibleRect is null, or orientation isn't one of
SwingConstants.VERTICAL or SwingConstants.HORIZONTAL
SwingConstants.VERTICAL, SwingConstants.HORIZONTAL.
-
See Also:
-
getScrollableBlockIncrement(java.awt.Rectangle, int, int)
Scrollable.getScrollableUnitIncrement(java.awt.Rectangle, int, int)
,
Scrollable.getScrollableUnitIncrement(java.awt.Rectangle, int, int)
getScrollableBlockIncrement
public int getScrollableBlockIncrement(Rectangle visibleRect,
int orientation,
int direction)
-
Returns the distance to scroll to expose the next or previous block.
For vertical scrolling, the following rules are used:
For vertical scrolling we are using the follows rules:
-
if scrolling
down, returns
down (direction is greater than 0),
the
distance to scroll so that the
last visible element
becomes
should become
the first completely visible element -
if scrolling up,
returns
the
distance to scroll so that the
first visible element
becomes
should become
the last completely visible element -
returns
visibleRect.height if the list is empty
For horizontal
scrolling, when
scrolling if
the
layout
list is layed out horizontally (the
orientation is
either
VERTICAL_WRAP or
HORIZONTAL_WRAP:
HORIZONTAL_WRAP):
-
if scrolling right, returns the distance to scroll so that the last visible element becomes the first completely visible element
-
if scrolling left, returns the distance to scroll so that the first visible element becomes the last completely visible element
-
returns visibleRect.width if the list is empty
-
if scrolling right (direction is greater than 0), the last visible element should become the first completely visible element
-
if scrolling left, the first visible element should become the last completely visible element
-
visibleRect.width if the list is empty
For horizontal scrolling and VERTICAL orientation, returns visibleRect.width.
Return visibleRect.width if the list is layed out vertically.
Note that the value of visibleRect must be the equal to this.getVisibleRect().
-
-
Specified by:
-
getScrollableBlockIncrement
in interface
Scrollable
-
-
Parameters:
-
visibleRect - the
view area
visible
within the viewport
rectangle
-
orientation -
SwingConstants.HORIZONTAL
HORIZONTAL
or
SwingConstants.VERTICAL
VERTICAL
-
direction - less or equal to zero to scroll up/back, greater than zero for down/forward
direction - if
<= 0, then scroll UP; if >
0, then scroll DOWN
-
Returns:
-
the "block" increment for scrolling in the specified direction; always positive
the block increment amount.
-
Throws:
-
IllegalArgumentException
- if visibleRect is null, or orientation isn't one of
SwingConstants.VERTICAL or SwingConstants.HORIZONTAL
SwingConstants.VERTICAL, SwingConstants.HORIZONTAL.
-
See Also:
-
getScrollableUnitIncrement(java.awt.Rectangle, int, int)
Scrollable.getScrollableUnitIncrement(java.awt.Rectangle, int, int)
,
Scrollable.getScrollableBlockIncrement(java.awt.Rectangle, int, int)
getScrollableTracksViewportWidth
public boolean getScrollableTracksViewportWidth()
-
Returns true if this JList is displayed in a JViewport and the viewport is wider than
the list's
JList's
preferred
width,
width;
or if the layout orientation is HORIZONTAL_WRAP and
visibleRowCount <= 0; otherwise returns false.
If false, then don't track
the
viewport's width. This allows horizontal scrolling if the JViewport
visible row count
is
itself embedded in a JScrollPane.
<= 0; otherwise returns false. If false, then don't track the viewport's width. This allows horizontal scrolling if the JViewport is itself embedded in a JScrollPane.
-
-
Specified by:
-
getScrollableTracksViewportWidth
in interface
Scrollable
-
-
Returns:
-
whether or not an enclosing viewport should force the list's width to match its own
true if viewport is wider than the JList's preferred width, otherwise false
-
See Also:
-
Scrollable.getScrollableTracksViewportWidth()
getScrollableTracksViewportHeight
public boolean getScrollableTracksViewportHeight()
-
Returns true if this JList is displayed in a JViewport and the viewport is taller than
the list's
JList's
preferred height, or if the layout orientation is VERTICAL_WRAP and
visibleRowCount <= 0; otherwise returns false.
If false, then don't track
the
viewport's height. This allows vertical scrolling if the JViewport
number of visible rows
is
itself embedded in a JScrollPane.
<= 0; otherwise returns false. If false, then don't track the viewport's height. This allows vertical scrolling if the JViewport is itself embedded in a JScrollPane.
-
-
Specified by:
-
getScrollableTracksViewportHeight
in interface
Scrollable
-
-
Returns:
-
whether or not an enclosing viewport should force the list's height to match its own
true if viewport is taller than Jlist's preferred height, otherwise false
-
See Also:
-
Scrollable.getScrollableTracksViewportHeight()
paramString
protected String paramString()
-
Returns a
String
string
representation of this JList. This method is intended to be used only for debugging purposes, and the content and format of the returned
String
string
may vary between implementations. The returned
String
string
may be
empty,
empty
but may not be null.
-
-
Overrides:
-
paramString
in class
JComponent
-
-
Returns:
-
a
String
string
representation of this JList.
getAccessibleContext
public AccessibleContext getAccessibleContext()
-
Gets the AccessibleContext associated with this JList. For
JList,
JLists,
the AccessibleContext takes the form of an AccessibleJList.
A new AccessibleJList instance is created if necessary.
-
-
Specified by:
-
getAccessibleContext
in interface
Accessible
-
Overrides:
-
getAccessibleContext
in class
JComponent
-
-
Returns:
-
an AccessibleJList that serves as the AccessibleContext of this JList