java.lang.Object java.awt.GridLayout
The GridLayout class is a layout manager that lays out a container's components in a rectangular grid. The container is divided into equal-sized rectangles, and one component is placed in each rectangle. For example, the following is an applet that lays out six buttons into three rows and two columns:
import java.awt.*; import java.applet.Applet; public class ButtonGrid extends Applet { public void init() { setLayout(new GridLayout(3,2)); add(new Button("1")); add(new Button("2")); add(new Button("3")); add(new Button("4")); add(new Button("5")); add(new Button("6")); } }
If the container's ComponentOrientation property is horizontal and left-to-right, the above example produces the output shown in Figure 1. If the container's ComponentOrientation property is horizontal and right-to-left, the example produces the output shown in Figure 2.
Figure 1: Horizontal, Left-to-Right | Figure 2: Horizontal, Right-to-Left |
When both the number of rows and the number of columns have been set to non-zero values, either by a constructor or by the setRows and setColumns methods, the number of columns specified is ignored. Instead, the number of columns is determined from the specified number or rows and the total number of components in the layout. So, for example, if three rows and two columns have been specified and nine components are added to the layout, they will be displayed as three rows of three columns. Specifying the number of columns affects the layout only when the number of rows is set to zero.
Constructor Summary | |
---|---|
GridLayout
() Creates a grid layout with a default of one column per component, in a single row. |
|
GridLayout
(int rows, int cols) Creates a grid layout with the specified number of rows and columns. |
|
GridLayout
(int rows, int cols, int hgap, int vgap) Creates a grid layout with the specified number of rows and columns. |
Method Summary | |
---|---|
void |
addLayoutComponent
(
String
name,
Component
comp) Adds the specified component with the specified name to the layout. |
int |
getColumns
() Gets the number of columns in this layout. |
int |
getHgap
() Gets the horizontal gap between components. |
int |
getRows
() Gets the number of rows in this layout. |
int |
getVgap
() Gets the vertical gap between components. |
void |
layoutContainer
(
Container
parent) Lays out the specified container using this layout. |
Dimension |
minimumLayoutSize
(
Container
parent) Determines the minimum size of the container argument using this grid layout. |
Dimension |
preferredLayoutSize
(
Container
parent) Determines the preferred size of the container argument using this grid layout. |
void |
removeLayoutComponent
(
Component
comp) Removes the specified component from the layout. |
void |
setColumns
(int cols) Sets the number of columns in this layout to the specified value. |
void |
setHgap
(int hgap) Sets the horizontal gap between components to the specified value. |
void |
setRows
(int rows) Sets the number of rows in this layout to the specified value. |
void |
setVgap
(int vgap) Sets the vertical gap between components to the specified value. |
String |
toString
() Returns the string representation of this grid layout's values. |
Methods inherited from class java.lang. Object |
---|
clone , equals , finalize , getClass , hashCode , notify , notifyAll , wait , wait , wait |
Constructor Detail |
---|
public GridLayout()
public GridLayout(int rows, int cols)
One, but not both, of rows and cols can be zero, which means that any number of objects can be placed in a row or in a column.
public GridLayout(int rows, int cols, int hgap, int vgap)
In addition, the horizontal and vertical gaps are set to the specified values. Horizontal gaps are placed
at the left and right edges, and
between each of the columns. Vertical gaps are placed
at the top and bottom edges, and
between each of the rows.
One, but not both, of rows and cols can be zero, which means that any number of objects can be placed in a row or in a column.
All GridLayout constructors defer to this one.
Method Detail |
---|
public int getRows()
public void setRows(int rows)
public int getColumns()
public void setColumns(int cols)
public int getHgap()
public void setHgap(int hgap)
public int getVgap()
public void setVgap(int vgap)
public void addLayoutComponent(String name, Component comp)
public void removeLayoutComponent(Component comp)
public Dimension preferredLayoutSize(Container parent)
The preferred width of a grid layout is the largest preferred width of
all
any
of the components in the container times the number of columns, plus the horizontal padding times the number of columns
minus
plus
one, plus the left and right insets of the target container.
The preferred height of a grid layout is the largest preferred height of
all
any
of the components in the container times the number of rows, plus the vertical padding times the number of rows
minus
plus
one, plus the top and bottom insets of the target container.
public Dimension minimumLayoutSize(Container parent)
The minimum width of a grid layout is the largest minimum width of
all
any
of the components in the container times the number of columns, plus the horizontal padding times the number of columns
minus
plus
one, plus the left and right insets of the target container.
The minimum height of a grid layout is the largest minimum height of
all
any
of the components in the container times the number of rows, plus the vertical padding times the number of rows
minus
plus
one, plus the top and bottom insets of the target container.
public void layoutContainer(Container parent)
This method reshapes the components in the specified target container in order to satisfy the constraints of the GridLayout object.
The grid layout manager determines the size of individual components by dividing the free space in the container into equal-sized portions according to the number of rows and columns in the layout. The container's free space equals the container's size minus any insets and any specified horizontal or vertical gap. All components in a grid layout are given the same size.
public String toString()