java.lang.Objectjavax.swing.ButtonGroup
public class ButtonGroup
This class is used to create a multiple-exclusion scope for a set of buttons. Creating a set of buttons with the same ButtonGroup object means that turning "on" one of those buttons turns off all other buttons in the group.
A ButtonGroup can be used with any set of objects that inherit from AbstractButton. Typically a button group contains instances of JRadioButton, JRadioButtonMenuItem, or JToggleButton. It wouldn't make sense to put an instance of JButton or JMenuItem in a button group because JButton and JMenuItem don't implement the selected state.
Initially, all buttons in the group are unselected.
Once any button is selected, one button is always selected in the group. There is no way to turn a button programmatically to "off", in order to clear the button group. To give the appearance of "none selected", add an invisible radio button to the group and then programmatically select that button to turn off all the displayed radio buttons. For example, a normal button with the label "none" could be wired to select the invisible radio button.
For examples and further information on using button groups see How to Use Radio Buttons , a section in The Java Tutorial.
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 .
Field Summary | |
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protected Vector < AbstractButton > |
buttons
|
Constructor Summary | |
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ButtonGroup
() Creates a new ButtonGroup. |
Method Summary | |
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void |
add
(
AbstractButton
b) Adds the button to the group. |
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int |
getButtonCount
() Returns the number of buttons in the group. |
Enumeration < AbstractButton > |
getElements
() Returns all the buttons that are participating in this group. |
ButtonModel |
getSelection
() Returns the model of the selected button. |
boolean |
isSelected
(
ButtonModel
m) Returns whether a ButtonModel is selected. |
void |
remove
(
AbstractButton
b) Removes the button from the group. |
void |
setSelected
(
ButtonModel
m, boolean b) Sets the selected value for the ButtonModel. |
Methods inherited from class java.lang. Object |
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clone , equals , finalize , getClass , hashCode , notify , notifyAll , toString , wait , wait , wait |
Field Detail |
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protected Vector<AbstractButton> buttons
Constructor Detail |
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public ButtonGroup()
Method Detail |
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public void add(AbstractButton b)
public void remove(AbstractButton b)
public void
clearSelection
()
public Enumeration<AbstractButton> getElements()
public ButtonModel getSelection()
public void setSelected(ButtonModel m, boolean b)
public boolean isSelected(ButtonModel m)
public int getButtonCount()