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Chapter 21 java.awt.event Reference |
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FocusEvent 
Name
FocusEvent
![[Graphic: Figure from the text]](./figs/focusev.gif)
Description
Focus events are generated when a component gets or loses input focus. Focus events come in two flavors, permanent and temporary. Permanent focus events occur with explicit focus changes. For example, when the user tabs through components, this causes permanent focus events. An example of a temporary focus event is when a component loses focus as its containing window is deactivated.
Class Definition
public class java.awt.event.FocusEvent
extends java.awt.event.ComponentEvent {
// Constants
public final static int FOCUS_FIRST;
public final static int FOCUS_GAINED;
public final static int FOCUS_LAST;
public final static int FOCUS_LOST;
// Constructors
public FocusEvent (Component source, int id);
public FocusEvent (Component source, int id, boolean temporary);
// Instance Methods
public boolean isTemporary();
public String paramString();
}
Constants
FOCUS_FIRST
public final static int FOCUS_FIRST
Specifies the beginning range of focus event ID values.
FOCUS_GAINED
public final static int FOCUS_GAINED
Event type ID indicating that the component gained the input focus.
FOCUS_LAST
public final static int FOCUS_LAST
Specifies the ending range of focus event ID values.
FOCUS_LOST
public final static int FOCUS_LOST
Event type ID indicating that the component lost the input focus.
Constructors
FocusEvent
public FocusEvent (Component source, int id)
- Parameters
-
- source
-
The object that generated the event.
- id
-
The event type ID of the event.
- source
- Description
-
Constructs a non-temporary FocusEvent with the given characteristics.
public FocusEvent (Component source, int id, boolean temporary)
- Parameters
-
- source
-
The object that generated the event.
- id
-
The event type ID of the event.
- temporary
-
A flag indicating whether this is a temporary focus event.
- source
- Description
-
Constructs a FocusEvent with the given characteristics.
Instance Methods
isTemporary
public boolean isTemporary()
- Returns
-
true if this is a temporary focus event; false otherwise.
paramString
public String paramString()
- Returns
-
String with current settings of the FocusEvent.
- Overrides
-
ComponentEvent.paramString()
- Description
-
Helper method for toString() to generate string of current settings.
See Also
Component, ComponentEvent, FocusAdapter, FocusListener
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| FocusAdapter |
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FocusListener |
