Interface ButtonModel
- All Superinterfaces:
- ItemSelectable
- All Known Implementing Classes:
- DefaultButtonModel, JToggleButton.ToggleButtonModel
public interface ButtonModel extends ItemSelectable
State model for buttons.
This model is used for regular buttons, as well as check boxes and radio buttons, which are special kinds of buttons. In practice, a button's UI takes the responsibility of calling methods on its model to manage the state, as detailed below:
In simple terms, pressing and releasing the mouse over a regular button triggers the button and causes and ActionEvent
to be fired. The same behavior can be produced via a keyboard key defined by the look and feel of the button (typically the SPACE BAR). Pressing and releasing this key while the button has focus will give the same results. For check boxes and radio buttons, the mouse or keyboard equivalent sequence just described causes the button to become selected.
In details, the state model for buttons works as follows when used with the mouse:
Pressing the mouse on top of a button makes the model both armed and pressed. As long as the mouse remains down, the model remains pressed, even if the mouse moves outside the button. On the contrary, the model is only armed while the mouse remains pressed within the bounds of the button (it can move in or out of the button, but the model is only armed during the portion of time spent within the button). A button is triggered, and an ActionEvent
is fired, when the mouse is released while the model is armed - meaning when it is released over top of the button after the mouse has previously been pressed on that button (and not already released). Upon mouse release, the model becomes unarmed and unpressed.
In details, the state model for buttons works as follows when used with the keyboard:
Pressing the look and feel defined keyboard key while the button has focus makes the model both armed and pressed. As long as this key remains down, the model remains in this state. Releasing the key sets the model to unarmed and unpressed, triggers the button, and causes an ActionEvent
to be fired.
Methods
Modifier and Type | Method and Description |
---|---|
void |
addActionListener(ActionListener l) Adds an |
void |
addChangeListener(ChangeListener l) Adds a |
void |
addItemListener(ItemListener l) Adds an |
String |
getActionCommand() Returns the action command string for the button. |
int |
getMnemonic() Gets the keyboard mnemonic for the button. |
boolean |
isArmed() Indicates partial commitment towards triggering the button. |
boolean |
isEnabled() Indicates if the button can be selected or triggered by an input device, such as a mouse pointer. |
boolean |
isPressed() Indicates if the button is pressed. |
boolean |
isRollover() Indicates that the mouse is over the button. |
boolean |
isSelected() Indicates if the button has been selected. |
void |
removeActionListener(ActionListener l) Removes an |
void |
removeChangeListener(ChangeListener l) Removes a |
void |
removeItemListener(ItemListener l) Removes an |
void |
setActionCommand(String s) Sets the action command string that gets sent as part of the |
void |
setArmed(boolean b) Marks the button as armed or unarmed. |
void |
setEnabled(boolean b) Enables or disables the button. |
void |
setGroup(ButtonGroup group) Identifies the group the button belongs to -- needed for radio buttons, which are mutually exclusive within their group. |
void |
setMnemonic(int key) Sets the keyboard mnemonic (shortcut key or accelerator key) for the button. |
void |
setPressed(boolean b) Sets the button to pressed or unpressed. |
void |
setRollover(boolean b) Sets or clears the button's rollover state |
void |
setSelected(boolean b) Selects or deselects the button. |
Methods inherited from interface java.awt.ItemSelectable
getSelectedObjects
Methods
isArmed
boolean isArmed()
Indicates partial commitment towards triggering the button.
- Returns:
-
true
if the button is armed, and ready to be triggered - See Also:
setArmed(boolean)
isSelected
boolean isSelected()
Indicates if the button has been selected. Only needed for certain types of buttons - such as radio buttons and check boxes.
- Returns:
-
true
if the button is selected
isEnabled
boolean isEnabled()
Indicates if the button can be selected or triggered by an input device, such as a mouse pointer.
- Returns:
-
true
if the button is enabled
isPressed
boolean isPressed()
Indicates if the button is pressed.
- Returns:
-
true
if the button is pressed
isRollover
boolean isRollover()
Indicates that the mouse is over the button.
- Returns:
-
true
if the mouse is over the button
setArmed
void setArmed(boolean b)
Marks the button as armed or unarmed.
- Parameters:
-
b
- whether or not the button should be armed
setSelected
void setSelected(boolean b)
Selects or deselects the button.
- Parameters:
-
b
-true
selects the button,false
deselects the button
setEnabled
void setEnabled(boolean b)
Enables or disables the button.
- Parameters:
-
b
- whether or not the button should be enabled - See Also:
isEnabled()
setPressed
void setPressed(boolean b)
Sets the button to pressed or unpressed.
- Parameters:
-
b
- whether or not the button should be pressed - See Also:
isPressed()
setRollover
void setRollover(boolean b)
Sets or clears the button's rollover state
- Parameters:
-
b
- whether or not the button is in the rollover state - See Also:
isRollover()
setMnemonic
void setMnemonic(int key)
Sets the keyboard mnemonic (shortcut key or accelerator key) for the button.
- Parameters:
-
key
- an int specifying the accelerator key
getMnemonic
int getMnemonic()
Gets the keyboard mnemonic for the button.
- Returns:
- an int specifying the accelerator key
- See Also:
setMnemonic(int)
setActionCommand
void setActionCommand(String s)
Sets the action command string that gets sent as part of the ActionEvent
when the button is triggered.
- Parameters:
-
s
- theString
that identifies the generated event - See Also:
-
getActionCommand()
,ActionEvent.getActionCommand()
getActionCommand
String getActionCommand()
Returns the action command string for the button.
- Returns:
- the
String
that identifies the generated event - See Also:
setActionCommand(java.lang.String)
setGroup
void setGroup(ButtonGroup group)
Identifies the group the button belongs to -- needed for radio buttons, which are mutually exclusive within their group.
- Parameters:
-
group
- theButtonGroup
the button belongs to
addActionListener
void addActionListener(ActionListener l)
Adds an ActionListener
to the model.
- Parameters:
-
l
- the listener to add
removeActionListener
void removeActionListener(ActionListener l)
Removes an ActionListener
from the model.
- Parameters:
-
l
- the listener to remove
addItemListener
void addItemListener(ItemListener l)
Adds an ItemListener
to the model.
- Specified by:
-
addItemListener
in interfaceItemSelectable
- Parameters:
-
l
- the listener to add - See Also:
ItemEvent
removeItemListener
void removeItemListener(ItemListener l)
Removes an ItemListener
from the model.
- Specified by:
-
removeItemListener
in interfaceItemSelectable
- Parameters:
-
l
- the listener to remove - See Also:
ItemEvent
addChangeListener
void addChangeListener(ChangeListener l)
Adds a ChangeListener
to the model.
- Parameters:
-
l
- the listener to add
removeChangeListener
void removeChangeListener(ChangeListener l)
Removes a ChangeListener
from the model.
- Parameters:
-
l
- the listener to remove
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https://docs.oracle.com/javase/8/docs/api/javax/swing/ButtonModel.html