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Java AWT Reference by John Zukowski

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21

java.awt.event Reference

21.1 ActionEvent images

Description

Action events are fired off when the user performs an action on a component, such as pushing a button, double-clicking on a list item, or selecting a menu item. There is only one action event type, ACTION_PERFORMED.

Class Definition

public class java.awt.event.ActionEvent
   extends java.awt.AWTEvent {

   // Constants
   public final static int ACTION_FIRST;
   public final static int ACTION_LAST;
   public final static int ACTION_PERFORMED;
   public final static int ALT_MASK;
   public final static int CTRL_MASK;
   public final static int META_MASK;
   public final static int SHIFT_MASK;

   // Constructors
   public ActionEvent (Object source, int id, String command);
   public ActionEvent (Object source, int id, String command, int modifiers);

   // Instance Methods
   public String getActionCommand();
   public int getModifiers();
public String paramString();
}

Constants

ACTION_FIRST

public final static int ACTION_FIRST

Specifies the beginning range of action event ID values.

ACTION_LAST

public final static int ACTION_LAST

Specifies the ending range of action event ID values.

ACTION_PERFORMED

public final static int ACTION_PERFORMED

The only action event type; it indicates that the user has performed an action.

ALT_MASK

public final static int ALT_MASK

A constant representing the ALT key. ORed with other masks to form modifiers setting of an AWTEvent.

CTRL_MASK

public final static int CTRL_MASK

A constant representing the Control key. ORed with other masks to form modifiers setting of an AWTEvent.

META_MASK

public final static int META_MASK

A constant representing the META key. ORed with other masks to form modifiers setting of an AWTEvent.

SHIFT_MASK

public final static int SHIFT_MASK

A constant representing the Shift key. ORed with other masks to form modifiers setting of an AWTEvent.

Constructors

ActionEvent

public ActionEvent (Object source, int id, String command)
Parameters source The object that generated the event.
id The type ID of the event.
command The action command string.
Description Constructs an ActionEvent with the given characteristics.
public ActionEvent (Object source, int id, String command, int modifiers)
Parameters source The object that generated the event.
id The type ID of the event.
command The action command string.
modifiers A combination of the key mask constants.
Description Constructs an ActionEvent with the given characteristics.

Instance Methods

getActionCommand

public String getActionCommand()
Returns The action command string for this ActionEvent.
Description Generally the action command string is the label of the component that generated the event. Also, when localization is necessary, the action command string can provide a setting that does not get localized.

getModifiers

public int getModifiers()
Returns A combination of the key mask constants.
Description Returns the modifier keys that were held down when this action was performed. This enables you to perform special processing if, for example, the user holds down Shift while pushing a button.

paramString

public String paramString()
Returns String with current settings of ActionEvent.
Overrides AWTEvent.paramString()
Description Helper method for toString() to generate string of current settings.

See Also

ActionListener, AWTEvent, String

21.2 ActionListener images

Description

Objects that implement the ActionListener interface can receive ActionEvent objects. Listeners must first register themselves with objects that produce events. When events occur, they are then automatically propagated to all registered listeners.

Interface Definition

public abstract interface java.awt.event.ActionListener
   extends java.util.EventListener {

   // Interface Methods
   public abstract void actionPerformed (ActionEvent e);
}

Interface Methods

actionPerformed

public abstract void actionPerformed (ActionEvent e)
Parameters e The action event that occurred.
Description Notifies the ActionListener that an event occurred.

See Also

ActionEvent, AWTEventMulticaster, EventListener

21.3 AdjustmentEvent images

Description

AdjustmentEvents are generated by objects that implement the Adjustable interface. Scrollbar is one example of such an object.

Class Definition

public class java.awt.event.AdjustmentEvent
   extends java.awt.AWTEvent {

   // Constants
   public final static int ADJUSTMENT_FIRST;
   public final static int ADJUSTMENT_LAST;
   public final static int ADJUSTMENT_VALUE_CHANGED;
   public final static int BLOCK_DECREMENT;
   public final static int BLOCK_INCREMENT;
   public final static int TRACK;
   public final static int UNIT_DECREMENT;
   public final static int UNIT_INCREMENT;

   // Constructors
   public AdjustmentEvent (Adjustable source, int id, int type, int value);

   // Instance Methods
   public Adjustable getAdjustable();
   public int getAdjustmentType();
   public int getValue();
   public String paramString();
}

Constants

ADJUSTMENT_FIRST

public final static int ADJUSTMENT_FIRST

Specifies the beginning range of adjustment event ID values.

ADJUSTMENT_LAST

public final static int ADJUSTMENT_LAST

Specifies the ending range of adjustment event ID values.

ADJUSTMENT_VALUE_CHANGED

public final static int ADJUSTMENT_VALUE_CHANGED

Event type ID for value changed.

BLOCK_DECREMENT

public final static int BLOCK_DECREMENT

Adjustment type for block decrement.

BLOCK_INCREMENT

public final static int BLOCK_INCREMENT

Adjustment type for block increment.

TRACK

public final static int TRACK

Adjustment type for tracking.

UNIT_DECREMENT

public final static int UNIT_DECREMENT

Adjustment type for unit decrement.

UNIT_INCREMENT

public final static int UNIT_INCREMENT

Adjustment type for unit increment.

Constructors

AdjustmentEvent

public AdjustmentEvent (Adjustable source, int id, int
type, int value)
Parameters source The object that generated the event.
id The event type ID of the event.
type The type of adjustment event.
value The value of the Adjustable object.
Description Constructs an AdjustmentEvent with the given characteristics.

Instance Methods

getAdjustable

public Adjustable getAdjustable()
Returns The source of this event.

getAdjustmentType

public int getAdjustmentType()
Returns One of the adjustment type constants.
Description The type will be BLOCK_DECREMENT, BLOCK_INCREMENT, TRACK, UNIT_DECREMENT, or UNIT_INCREMENT.

getValue

public int getValue()
Returns The new value of the Adjustable object.

paramString

public String paramString()
Returns String with current settings of the AdjustmentEvent.
Overrides AWTEvent.paramString()
Description Helper method for toString() to generate string of current settings.

See Also

Adjustable, AdjustmentListener, AWTEvent, Scrollbar

21.4 AdjustmentListener images

Description

Objects that implement the AdjustmentListener interface can receive AdjustmentEvent objects. Listeners must first register themselves with objects that produce events. When events occur, they are then automatically propagated to all registered listeners.

Interface Definition

public abstract interface java.awt.event.AdjustmentListener
   extends java.util.Eventlistener {

  // Interface Methods
  public abstract void adjustmentValueChanged (AdjustmentEvent e);
}

Interface Methods

adjustmentPerformed

public abstract void adjustmentValueChanged
(AdjustmentEvent e)
Parameters e The adjustment event that occurred.
Description Notifies the AdjustmentListener that an event occurred.

See Also

AdjustmentEvent, AWTEventMulticaster, EventListener

21.5 ComponentAdapter images

images

Description

ComponentAdapter is a class that implements the methods of ComponentListener with empty functions. It may be easier for you to extend ComponentAdapter, overriding only those methods you are interested in, than to implement ComponentListener and provide the empty functions yourself.

Class Definition

public abstract class java.awt.event.ComponentAdapter
   extends java.lang.Object
   implements java.awt.event.ComponentListener {

  // Instance Methods
  public void componentHidden (ComponentEvent e);
  public void componentMoved (ComponentEvent e);
  public void componentResized (ComponentEvent e);
  public void componentShown (ComponentEvent e);
}

Instance Methods

componentHidden

public void componentHidden (ComponentEvent e)
Parameters e The event that has occurred.
Description Does nothing. Override this function to be notified when a component is hidden.

componentMoved

public void componentMoved (ComponentEvent e)
Parameters e The event that has occurred.
Description Does nothing. Override this function to be notified when a component is moved.

componentResized

public void componentResized (ComponentEvent e)
Parameters e The event that has occurred.
Description Does nothing. Override this function to be notified when a component is resized.

componentShown

public void componentShown (ComponentEvent e)
Parameters e The event that has occurred.
Description Does nothing. Override this function to be notified when a component is shown.

See Also

Component, ComponentEvent, ComponentListener

21.6 ComponentEvent images

Description

Component events are generated when a component is shown, hidden, moved, or resized. AWT automatically deals with component moves and resizing; these events are provided only for notification. Subclasses of ComponentEvent deal with other specific component-level events.

Class Definition

public class java.awt.event.ComponentEvent
   extends java.awt.AWTEvent {

  // Constants
  public final static int COMPONENT_FIRST;
  public final static int COMPONENT_HIDDEN;
  public final static int COMPONENT_LAST;
  public final static int COMPONENT_MOVED;
  public final static int COMPONENT_RESIZED;
  public final static int COMPONENT_SHOWN;

  // Constructors
  public ComponentEvent (Component source, int id);

  // Instance Methods
  public Component getComponent();
  public String paramString();
}

Constants

COMPONENT_FIRST

public final static int COMPONENT_FIRST

Specifies the beginning range of component event ID values.

COMPONENT_HIDDEN

public final static int COMPONENT_HIDDEN

Event type ID indicating that the component was hidden.

COMPONENT_LAST

public final static int COMPONENT_LAST

Specifies the ending range of component event ID values.

COMPONENT_MOVED

public final static int COMPONENT_MOVED

Event type ID indicating that the component was moved.

COMPONENT_RESIZED

public final static int COMPONENT_RESIZED

Event type ID indicating that the component was resized.

COMPONENT_SHOWN

public final static int COMPONENT_SHOWN

Event type ID indicating that the component was shown.

Constructors

ComponentEvent

public ComponentEvent (Component source, int id)
Parameters source The object that generated the event.
id The event type ID of the event.
Description Constructs a ComponentEvent with the given characteristics.

Instance Methods

getComponent

public Component getComponent()
Returns The source of this event.

paramString

public String paramString()
Returns String with current settings of the ComponentEvent.
Overrides AWTEvent.paramString()
Description Helper method for toString() to generate string of current settings.

See Also

AWTEvent, Component, ComponentAdapter, ComponentListener, ContainerEvent, FocusEvent, InputEvent, PaintEvent, WindowEvent

21.7 ComponentListener images

Description

Objects that implement the ComponentListener interface can receive ComponentEvent objects. Listeners must first register themselves with objects that produce events. When events occur, they are then automatically propagated to all registered listeners.

Interface Definition

public abstract interface java.awt.event.ComponentListener
   extends java.util.EventListener {

  // Instance Methods
  public abstract void componentHidden (ComponentEvent e);
  public abstract void componentMoved (ComponentEvent e);
  public abstract void componentResized (ComponentEvent e);
  public abstract void componentShown (ComponentEvent e);
}

Interface Methods

componentHidden

public abstract void componentHidden (ComponentEvent e)
Parameters e The component event that occurred.
Description Notifies the ComponentListener that a component was hidden.

componentMoved

public abstract void componentMoved (ComponentEvent e)
Parameters e The component event that occurred.
Description Notifies the ComponentListener that a component was moved.

componentResized

public abstract void componentResized (ComponentEvent e)
Parameters e The component event that occurred.
Description Notifies the ComponentListener that a component was resized.

componentShown

public abstract void componentShown (ComponentEvent e)
Parameters e The component event that occurred.
Description Notifies the ComponentListener that a component was shown.

See Also

AWTEventMulticaster, ComponentAdapter, ComponentEvent, EventListener

21.8 ContainerAdapter images

images

Description

The ContainerAdapter class implements the methods of ContainerListener with empty functions. It may be easier for you to extend ContainerAdapter, overriding only those methods you are interested in, than to implement ContainerListener and provide the empty functions yourself.

Class Definition

public abstract class java.awt.event.ContainerAdapter
   extends java.lang.Object
   implements java.awt.event.ContainerListener {

  // Instance Methods
public void componentAdded (ContainerEvent e);
  public void componentRemoved (ContainerEvent e);
}

Instance Methods

componentAdded

public void componentAdded (ComponentEvent e)
Parameters e The event that has occurred.
Description Does nothing. Override this function to be notified when a component is added to a container.

componentRemoved

public void componentRemoved (ComponentEvent e)
Parameters e The event that has occurred.
Description Does nothing. Override this function to be notified when a component is removed from a container.

See Also

ContainerEvent, ContainerListener

21.9 ContainerEvent images

Description

Container events are fired off when a component is added to or removed from a container. The AWT automatically deals with adding components to containers; these events are provided only for notification.

Class Definition

public class java.awt.event.ContainerEvent
   extends java.awt.event.ComponentEvent {

  // Constants
  public final static int COMPONENT_ADDED;
  public final static int COMPONENT_REMOVED;
  public final static int CONTAINER_FIRST;
  public final static int CONTAINER_LAST;

  // Constructors
  public ContainerEvent (Component source, int id, Component child);

  // Instance Methods
public Component getChild();
  public Container getContainer();
  public String paramString();
}

Constants

COMPONENT_ADDED

public final static int COMPONENT_ADDED

Event type ID indicating that a component was added to a container.

CONTAINER_FIRST

public final static int CONTAINER_FIRST

Specifies the beginning range of container event ID values.

CONTAINER_LAST

public final static int CONTAINER_LAST

Specifies the ending range of container event ID values.

COMPONENT_REMOVED

public final static int COMPONENT_REMOVED

Event type ID indicating that a component was removed from a container.

Constructors

ContainerEvent

public ContainerEvent (Component source, int id, Component
child)
Parameters source The object that generated the event.
id The event type ID of the event.
child The component that was added or removed.
Description Constructs a ContainerEvent with the given characteristics.

Instance Methods

getChild

public Component getChild()
Returns The component that is being added or removed.

getContainer

public Container getContainer()
Returns The container for this event.

paramString

public String paramString()
Returns String with current settings of the ContainerEvent.
Overrides ComponentEvent.paramString()
Description Helper method for toString() to generate string of current settings.

See Also

Component, ComponentEvent, Container, ContainerAdapter, ContainerListener

21.10 ContainerListener images

Description

Objects that implement the ContainerListener interface can receive ContainerEvent objects. Listeners must first register themselves with objects that produce events. When events occur, they are then automatically propagated to all registered listeners.

Interface Definition

public abstract interface java.awt.event.ContainerListener
   extends java.util.EventListener {

  // Instance Methods
  public abstract void componentAdded (ContainerEvent e);
  public abstract void componentRemoved (ContainerEvent e);
}

Interface Methods

componentAdded

public abstract void componentAdded (ContainerEvent e)
Parameters e The event that occurred.
Description Notifies the ContainerListener that a component has been added to the container.

componentRemoved

public abstract void componentRemoved (ContainerEvent e)
Parameters e The event that occurred.
Description Notifies the ContainerListener that a component has been removed from the container.

See Also

ContainerAdapter, ContainerEvent, EventListener

21.11 FocusAdapter images

Description

The FocusAdapter class implements the methods of FocusListener with empty functions. It may be easier for you to extend FocusAdapter, overriding only those methods you are interested in, than to implement FocusListener and provide the empty functions yourself.

Class Definition

public abstract class java.awt.event.FocusAdapter
   extends java.lang.Object
  implements java.awt.event.FocusListener {

  // Instance Methods
  public void focusGained (FocusEvent e);
  public void focusLost (FocusEvent e);
}

Instance Methods

focusGained

public void focusGained (FocusEvent e)
Parameters e The event that has occurred.
Description Does nothing. Override this function to be notified when a component gains focus.

focusLost

public void focusLost (FocusEvent e)
Parameters e The event that has occurred.
Description Does nothing. Override this function to be notified when a component loses focus.

See Also

FocusEvent, FocusListener

21.12 FocusEvent images

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.
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.
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

21.13 FocusListener images

Description

Objects that implement the FocusListener interface can receive FocusEvent objects. Listeners must first register themselves with objects that produce events. When events occur, they are then automatically propagated to all registered listeners.

Interface Definition

public abstract interface java.awt.event.FocusListener
   extends java.util.EventListener {

  // Instance Methods
  public abstract void focusGained (FocusEvent e);
  public abstract void focusLost (FocusEvent e);
}

Interface Methods

focusGained

public abstract void focusGained (FocusEvent e)
Parameters e The component event that occurred.
Description Notifies the FocusListener that a component gained the input focus.

focusLost

public abstract void focusLost (FocusEvent e)
Parameters e The component event that occurred.
Description Notifies the FocusListener that a component lost the input focus.

See Also

AWTEventMulticaster, EventListener, FocusAdapter, FocusEvent

21.14 InputEvent images

Description

InputEvent is the root class for representing user input events. Input events are passed to listeners before the event source processes them. If one of the listeners consumes an event by using consume(), the event will not be processed by the event source peer.

Class Definition

public abstract class java.awt.event.InputEvent
   extends java.awt.event.ComponentEvent {

  // Constants
  public final static int ALT_MASK;
  public final static int BUTTON1_MASK;
  public final static int BUTTON2_MASK;
  public final static int BUTTON3_MASK;
  public final static int CTRL_MASK;
  public final static int META_MASK;
  public final static int SHIFT_MASK;

  // Instance Methods
  public void consume();
  public int getModifiers();
  public long getWhen();
  public boolean isAltDown();
  public boolean isConsumed();
  public boolean isControlDown();
  public boolean isMetaDown();
  public boolean isShiftDown();
}

Constants

ALT_MASK

public final static int ALT_MASK

The ALT key mask. ORed with other masks to form modifiers setting of event.

BUTTON1_MASK

public final static int BUTTON1_MASK

The mouse button 1 key mask. ORed with other masks to form modifiers setting of event.

BUTTON2_MASK

public final static int BUTTON2_MASK

The mouse button 2 key mask. ORed with other masks to form modifiers setting of event. This constant is identical to ALT_MASK.

BUTTON3_MASK

public final static int BUTTON3_MASK

The mouse button 3 key mask. ORed with other masks to form modifiers setting of event. This constant is identical to ALT_MASK.

CTRL_MASK

public final static int CTRL_MASK

The Control key mask. ORed with other masks to form modifiers setting of event.

META_MASK

public final static int META_MASK

The Meta key mask. ORed with other masks to form modifiers setting of event.

SHIFT_MASK

public final static int SHIFT_MASK

The Shift key mask. ORed with other masks to form modifiers setting of event.

Instance Methods

consume

public void consume()
Description A consumed event will not be delivered to its source for default processing.

getModifiers

public int getModifiers()
Returns The modifier flags, a combination of the _MASK constants.
Description Use this method to find out what modifier keys were pressed when an input event occurred.

getWhen

public long getWhen()
Returns The time at which this event occurred.
Description The time of the event is returned as the number of milliseconds since the epoch (00:00:00 UTC, January 1, 1970). Conveniently, java.util.Date has a constructor that accepts such values.

isAltDown

public boolean isAltDown()
Returns true if the Alt key was pressed; false otherwise.

isConsumed

public boolean isConsumed()
Returns true if the event has been consumed; false otherwise.

isControlDown

public boolean isControlDown()
Returns true if the Control key was pressed; false otherwise.

isMetaDown

public boolean isMetaDown()
Returns true if the Meta key was pressed; false otherwise.

isShiftDown

public boolean isShiftDown()
Returns true if the Shift key was pressed; false otherwise.

See Also

ComponentEvent, KeyEvent, MouseEvent

21.15 ItemEvent images

Description

ItemEvents are generated by objects that implement the ItemSelectable interface. Choice is one example of such an object.

Class Definition

public class java.awt.event.ItemEvent
   extends java.awt.AWTEvent {

  // Constants
  public final static int DESELECTED;
  public final static int ITEM_FIRST;
  public final static int ITEM_LAST;
  public final static int ITEM_STATE_CHANGED;
  public final static int SELECTED;

  // Constructors
  public ItemEvent (ItemSelectable source, int id, Object item, int stateChange);

// Instance Methods
  public Object getItem();
  public ItemSelectable getItemSelectable();
  public int getStateChange();
  public String paramString();
}

Constants

DESELECTED

public final static int DESELECTED

Indicates that an item was deselected.

ITEM_FIRST

public final static int ITEM_FIRST

Specifies the beginning range of item event ID values.

ITEM_LAST

public final static int ITEM_LAST

Specifies the ending range of item event ID values.

ITEM_STATE_CHANGED

public final static int ITEM_STATE_CHANGED

An event type indicating that an item was selected or deselected.

SELECTED

public final static int SELECTED

Indicates that an item was selected.

Constructors

ItemEvent

public ItemEvent (ItemSelectable source, int id, Object
item, int stateChange)
Parameters source The object that generated the event.
id The type ID of the event.
item The item whose state is changing.
stateChange Either SELECTED or DESELECTED.
Description Constructs an ItemEvent with the given characteristics.

Instance Methods

getItem

public Object getItem()
Returns The item pertaining to this event.
Description Returns the item whose changed state triggered this event.

getItemSelectable

public ItemSelectable getItemSelectable()
Returns The source of this event.
Description Returns an object that implements the ItemSelectable interface.

getStateChange

public int getStateChange()
Returns The change in state that triggered this event. The new state is returned.
Description This method will return SELECTED or DESELECTED.

paramString

public String paramString()
Returns String with current settings of ItemEvent.
Overrides AWTEvent.paramString()
Description Helper method for toString() to generate string of current settings.

See Also

AWTEvent, ItemSelectable, ItemListener

21.16 ItemListener images

Description

Objects that implement the ItemListener interface can receive ItemEvent objects. Listeners must first register themselves with objects that produce events. When events occur, they are then automatically propagated to all registered listeners.

Interface Definition

public abstract interface java.awt.event.ItemListener
   extends java.util.EventListener {

  // Interface Methods
  public abstract void itemStateChanged (ItemEvent e);
}

Interface Methods

itemStateChanged

public abstract void itemStateChanged (ItemEvent e)
Parameters e The item event that occurred.
Description Notifies the ItemListener that an event occurred.

See Also

AWTEventMulticaster, EventListener, ItemEvent

21.17 KeyAdapter images

Description

The KeyAdapter class implements the methods of KeyListener with empty functions. It may be easier for you to extend KeyAdapter, overriding only those methods you are interested in, than to implement KeyListener and provide the empty functions yourself.

Class Definition

public abstract class java.awt.event.KeyAdapter
   extends java.lang.Object
   implements java.awt.event.KeyListener {

  // Instance Methods
  public void keyPressed (KeyEvent e);
  public void keyReleased (KeyEvent e);
  public void keyTyped (KeyEvent e);
}

Instance Methods

keyPressed

public void keyPressed (KeyEvent e)
Parameters e The event that has occurred.
Description Does nothing. Override this function to be notified when a key is pressed.

keyReleased

public void keyReleased (KeyEvent e)
Parameters e The event that has occurred.
Description Does nothing. Override this function to be notified when a pressed key is released.

keyTyped

public void keyTyped (KeyEvent e)
Parameters e The event that has occurred.
Description Does nothing. Override this function to be notified when a key has been pressed and released.

See Also

KeyEvent, KeyListener

21.18 KeyEvent images

Description

Key events are generated when the user types on the keyboard.

Class Definition

public class java.awt.event.KeyEvent
   extends java.awt.event.InputEvent {

  // Constants
  public final static int CHAR_UNDEFINED;
  public final static int KEY_FIRST;
  public final static int KEY_LAST;
  public final static int KEY_PRESSED;
  public final static int KEY_RELEASED;
  public final static int KEY_TYPED;
  public final static int VK_0;
  public final static int VK_1;
  public final static int VK_2;
  public final static int VK_3;
  public final static int VK_4;
  public final static int VK_5;
  public final static int VK_6;
  public final static int VK_7;
  public final static int VK_8;
  public final static int VK_9;
  public final static int VK_A;
  public final static int VK_ACCEPT;
  public final static int VK_ADD;
public final static int VK_ALT;
  public final static int VK_B;
  public final static int VK_BACK_QUOTE;
  public final static int VK_BACK_SLASH;
  public final static int VK_BACK_SPACE;
  public final static int VK_C;
  public final static int VK_CANCEL;
  public final static int VK_CAPS_LOCK;
  public final static int VK_CLEAR;
  public final static int VK_CLOSE_BRACKET;
  public final static int VK_COMMA;
  public final static int VK_CONTROL;
  public final static int VK_CONVERT;
  public final static int VK_D;
  public final static int VK_DECIMAL;
  public final static int VK_DELETE;
  public final static int VK_DIVIDE;
  public final static int VK_DOWN;
  public final static int VK_E;
  public final static int VK_END;
  public final static int VK_ENTER;
  public final static int VK_EQUALS;
  public final static int VK_ESCAPE;
  public final static int VK_F;
  public final static int VK_F1;
  public final static int VK_F2;
  public final static int VK_F3;
  public final static int VK_F4;
  public final static int VK_F5;
  public final static int VK_F6;
  public final static int VK_F7;
  public final static int VK_F8;
  public final static int VK_F9;
  public final static int VK_F10;
  public final static int VK_F11;
  public final static int VK_F12;
  public final static int VK_FINAL;
  public final static int VK_G;
  public final static int VK_H;
  public final static int VK_HELP;
  public final static int VK_HOME;
  public final static int VK_I;
  public final static int VK_INSERT;
  public final static int VK_J;
  public final static int VK_K;
  public final static int VK_KANA;
  public final static int VK_KANJI;
  public final static int VK_L;
  public final static int VK_LEFT;
public final static int VK_M;
  public final static int VK_META;
  public final static int VK_MODECHANGE;
  public final static int VK_MULTIPLY;
  public final static int VK_N;
  public final static int VK_NONCONVERT;
  public final static int VK_NUM_LOCK;
  public final static int VK_NUMPAD0;
  public final static int VK_NUMPAD1;
  public final static int VK_NUMPAD2;
  public final static int VK_NUMPAD3;
  public final static int VK_NUMPAD4;
  public final static int VK_NUMPAD5;
  public final static int VK_NUMPAD6;
  public final static int VK_NUMPAD7;
  public final static int VK_NUMPAD8;
  public final static int VK_NUMPAD9;
  public final static int VK_O;
  public final static int VK_OPEN_BRACKET;
  public final static int VK_P;
  public final static int VK_PAGE_DOWN;
  public final static int VK_PAGE_UP;
  public final static int VK_PAUSE;
  public final static int VK_PERIOD;
  public final static int VK_PRINTSCREEN;
  public final static int VK_Q;
  public final static int VK_QUOTE;
  public final static int VK_R;
  public final static int VK_RIGHT;
  public final static int VK_S;
  public final static int VK_SCROLL_LOCK;
  public final static int VK_SEMICOLON;
  public final static int VK_SEPARATER;
  public final static int VK_SHIFT;
  public final static int VK_SLASH;
  public final static int VK_SPACE;
  public final static int VK_SUBTRACT;
  public final static int VK_T;
  public final static int VK_TAB;
  public final static int VK_U;
  public final static int VK_UNDEFINED;
  public final static int VK_UP;
  public final static int VK_V;
  public final static int VK_W;
  public final static int VK_X;
  public final static int VK_Y;
  public final static int VK_Z;

  // Constructors
public KeyEvent (Component source, int id, long when, int modifiers,
    int keyCode, char keyChar);

  // Class Methods
  public static String getKeyModifiersText(int modifiers);
  public static String getKeyText(int keyCode);

  // Instance Methods
  public char getKeyChar();
  public int getKeyCode();
  public boolean isActionKey();
  public String paramString();
  public void setKeyChar (char keyChar);
  public void setKeyCode (int keyCode);
  public void setModifiers (int modifiers);
}

Constants

CHAR_UNDEFINED

public final static int CHAR_UNDEFINED

This constant is used for key presses have that no associated character.

KEY_FIRST

public final static int KEY_FIRST

Specifies the beginning range of key event ID values.

KEY_LAST

public final static int KEY_LAST

Specifies the ending range of key event ID values.

KEY_PRESSED

public final static int KEY_PRESSED

An event ID type for a key press.

KEY_RELEASED

public final static int KEY_RELEASED

An event ID type for a key release.

KEY_TYPED

public final static int KEY_TYPED

An event ID type for a typed key (a press and a release).

VK_0

public final static int VK_0

The 0 key.

VK_1

public final static int VK_1

The 1 key.

VK_2

public final static int VK_2

The 2 key.

VK_3

public final static int VK_3

The 3 key.

VK_4

public final static int VK_4

The 4 key.

VK_5

public final static int VK_5

The 5 key.

VK_6

public final static int VK_6

The 6 key.

VK_7

public final static int VK_7

The 7 key.

VK_8

public final static int VK_8

The 8 key.

VK_9

public final static int VK_9

The 9 key.

VK_A

public final static int VK_A

The ‘a’ key.

VK_ACCEPT

public final static int VK_ACCEPT

This constant is used for Asian keyboards.

VK_ADD

public final static int VK_ADD

The plus (+) key on the numeric keypad.

VK_ALT

public final static int VK_ALT

The Alt key.

VK_B

public final static int VK_B

The ‘b’ key.

VK_BACK_QUOTE

public final static int VK_BACK_QUOTE

The backquote (‘) key.

VK_BACK_SLASH

public final static int VK_BACK_SLASH

The backslash key.

VK_BACK_SPACE

public final static int VK_BACK_SPACE

The Backspace key.

VK_C

public final static int VK_C

The ‘c’ key.

VK_CANCEL

public final static int VK_CANCEL

The Cancel key.

VK_CAPS_LOCK

public final static int VK_CAPS_LOCK

The Caps Lock key.

VK_CLEAR

public final static int VK_CLEAR

The Clear key.

VK_CLOSE_BRACKET

public final static int VK_CLOSE_BRACKET

The close bracket ‘]’ key.

VK_COMMA

public final static int VK_COMMA

The comma (,) key.

VK_CONTROL

public final static int VK_CONTROL

The Control key.

VK_CONVERT

public final static int VK_CONVERT

This constant is used for Asian keyboards.

VK_D

public final static int VK_D

The ‘d’ key.

VK_DECIMAL

public final static int VK_DECIMAL

The decimal (.) key on the numeric keypad.

VK_DELETE

public final static int VK_DELETE

The Delete key.

VK_DIVIDE

public final static int VK_DIVIDE

The divide (/) key on the numeric keypad.

VK_DOWN

public final static int VK_DOWN

The Down arrow key.

VK_E

public final static int VK_E

The ‘e’ key.

VK_END

public final static int VK_END

The End key.

VK_ENTER

public final static int VK_ENTER

The Enter key.

VK_EQUALS

public final static int VK_ EQUALS

The equals (=) key.

VK_ESCAPE

public final static int VK_ESCAPE

The Escape key.

VK_F

public final static int VK_F

The ‘f’ key.

VK_F1

public final static int VK_F1

The F1 key.

VK_F2

public final static int VK_F2

The F2 key.

VK_F3

public final static int VK_F3

The F3 key.

VK_F4

public final static int VK_F4

The F4 key.

VK_F5

public final static int VK_F5

The F5 key.

VK_F6

public final static int VK_F6

The F6 key.

VK_F7

public final static int VK_F7

The F7 key.

VK_F8

public final static int VK_F8

The F8 key.

VK_F9

public final static int VK_F9

The F9 key.

VK_F10

public final static int VK_F10

The F10 key.

VK_F11

public final static int VK_F11

The F11 key.

VK_F12

public final static int VK_F12

The F12 key.

VK_FINAL

public final static int VK_FINAL

This constant is used for Asian keyboards.

VK_G

public final static int VK_G

The ‘g’ key.

VK_H

public final static int VK_H

The ‘h’ key.

VK_HELP

public final static int VK_HELP

The Help key.

VK_HOME

public final static int VK_HOME

The Home key.

VK_I

public final static int VK_I

The ‘i’ key.

VK_INSERT

public final static int VK_INSERT

The Insert key.

VK_J

public final static int VK_J

The ‘j’ key.

VK_K

public final static int VK_K

The ‘k’ key.

VK_KANA

public final static int VK_KANA

This constant is used for Asian keyboards.

VK_KANJI

public final static int VK_KANJI

This constant is used for Asian keyboards.

VK_L

public final static int VK_L

The ‘l’ key.

VK_LEFT

public final static int VK_LEFT

The Left arrow key.

VK_M

public final static int VK_M

The ‘m’ key.

VK_MODECHANGE

public final static int VK_MODECHANGE

This constant is used for Asian keyboards.

VK_META

public final static int VK_META

The Meta key.

VK_MULTIPLY

public final static int VK_MULTIPLY

The * key on the numeric keypad.

VK_N

public final static int VK_N

The ‘n’ key.

VK_NONCONVERT

public final static int VK_NONCONVERT

This constant is used for Asian keyboards.

VK_NUM_LOCK

public final static int VK_NUM_LOCK

The Num Lock key.

VK_NUMPAD0

public final static int VK_NUMPAD0

The 0 key on the numeric keypad.

VK_NUMPAD1

public final static int VK_NUMPAD1

The 1 key on the numeric keypad.

VK_NUMPAD2

public final static int VK_NUMPAD2

The 2 key on the numeric keypad.

VK_NUMPAD3

public final static int VK_NUMPAD3

The 3 key on the numeric keypad.

VK_NUMPAD4

public final static int VK_NUMPAD4

The 4 key on the numeric keypad.

VK_NUMPAD5

public final static int VK_NUMPAD5

The 5 key on the numeric keypad.

VK_NUMPAD6

public final static int VK_NUMPAD6

The 6 key on the numeric keypad.

VK_NUMPAD7

public final static int VK_NUMPAD7

The 7 key on the numeric keypad.

VK_NUMPAD8

public final static int VK_NUMPAD8

The 8 key on the numeric keypad.

VK_NUMPAD9

public final static int VK_NUMPAD9

The 9 key on the numeric keypad.

VK_O

public final static int VK_O

The ‘o’ key.

VK_OPEN_BRACKET

public final static int VK_OPEN_BRACKET

The open bracket ‘[‘ key.

VK_P

public final static int VK_P

The ‘p’ key.

VK_PAGE_DOWN

public final static int VK_PAGE_DOWN

The Page Down key.

VK_PAGE_UP

public final static int VK_PAGE_UP

The Page Up key.

VK_PAUSE

public final static int VK_PAUSE

The Pause key.

VK_PERIOD

public final static int VK_PERIOD

The period (.) key.

VK_PRINTSCREEN

public final static int VK_PRINTSCREEN

The Print Screen key.

VK_Q

public final static int VK_Q

The ‘q’ key.

VK_QUOTE

public final static int VK_QUOTE

The quotation mark (”) key.

VK_R

public final static int VK_R

The ‘r’ key.

VK_RIGHT

public final static int VK_RIGHT

The Right arrow key.

VK_S

public final static int VK_S

The ‘s’ key.

VK_SCROLL_LOCK

public final static int VK_SCROLL_LOCK

The Scroll Lock key.

VK_SEMICOLON

public final static int VK_SEMICOLON

The semicolon (;) key.

VK_SEPARATER

public final static int VK_SEPARATER

The numeric separator key on the numeric keypad (i.e., the locale-dependent key used to separate groups of digits). A misspelling of VK_SEPARATOR.

VK_SHIFT

public final static int VK_SHIFT

The Shift key.

VK_SLASH

public final static int VK_SLASH

The slash (/) key.

VK_SPACE

public final static int VK_SPACE

The space key.

VK_SUBTRACT

public final static int VK_SUBTRACT

The subtract (−) key on the numeric keypad.

VK_T

public final static int VK_T

The ‘t’ key.

VK_TAB

public final static int VK_TAB

The Tab key.

VK_U

public final static int VK_U

The ‘u’ key.

VK_UNDEFINED

public final static int VK_UNDEFINED

An undefined key.

VK_UP

public final static int VK_UP

The Up arrow key.

VK_V

public final static int VK_V

The ‘v’ key.

VK_W

public final static int VK_W

The ‘w’ key.

VK_X

public final static int VK_X

The ‘x’ key.

VK_Y

public final static int VK_Y

The ‘y’ key.

VK_Z

public final static int VK_Z

The ‘z’ key.

Constructors

KeyEvent

public KeyEvent (Component source, int id, long when, int
modifiers, int keyCode, char keyChar)
Parameters source The object that generated the event.
id The event type ID of the event.
when When the event occurred, in milliseconds from the epoch.
modifiers What modifier keys were pressed with this key.
keyCode The code of the key.
keyChar The character for this key.
Description Constructs a KeyEvent with the given characteristics.

Class Methods

getKeyModifiersText

public static String getKeyModifiersText(int modifiers)
Parameters modifiers One or more modifier keys.
Returns A string describing the modifiers.

getKeyText

public static String getKeyText(int keyCode)
Parameters keyCode One of the key codes.
Returns A string describing the given key.

Instance Methods

getKeyChar

public char getKeyChar()
Returns The character corresponding to this event. KEY_TYPED events have characters.

getKeyCode

public int getKeyCode()
Returns The integer key code corresponding to this event. This will be one of the constants defined above. KEY_PRESSED and KEY_RELEASED events have codes. Key codes are virtual keys, not actual. Pressing the ‘a’ key is identical to ‘A’, but has different modifiers. Same for ‘/’ and ‘?’ on a standard keyboard.

isActionKey

public boolean isActionKey()
Returns true if this event is for one of the action keys; false otherwise.
Description In general, an action key is a key that causes an action but has no printing equivalent. The action keys are the function keys, the arrow keys, Caps Lock, End, Home, Insert, Num Lock, Pause, Page Down, Page Up, Print Screen, and Scroll Lock. They do not generate a KEY_TYPED event, only KEY_PRESSED and KEY_RELEASED.

paramString

public String paramString()
Returns A string with current settings of the KeyEvent.
Overrides ComponentEvent.paramString()
Description Helper method for toString() to generate string of current settings.

setKeyChar

public void setKeyChar(char keyChar)
Parameters keyChar The new key character.
Description Sets the character code of this KeyEvent.

setKeyCode

public void setKeyCode (int keyCode)
Parameters keyCode The new key code.
Description Sets the key code of this KeyEvent.

setModifiers

public void setModifiers (int modifiers)
Parameters modifiers The new modifiers.
Description This is a combination of the mask constants defined in java.awt.event.InputEvent.

See Also

Component, ComponentEvent, InputEvent, KeyAdapter, KeyListener

21.19 KeyListener images

Description

Objects that implement the KeyListener interface can receive KeyEvent objects. Listeners must first register themselves with objects that produce events. When events occur, they are then automatically propagated to all registered listeners.

Interface Definition

public abstract interface java.awt.event.KeyListener
   extends java.util.EventListener {

  // Instance Methods
  public abstract void keyPressed (KeyEvent e);
  public abstract void keyReleased (KeyEvent e);
  public abstract void keyTyped (KeyEvent e);
}

Interface Methods

keyPressed

public abstract void keyPressed (KeyEvent e)
Parameters e The key event that occurred.
Description Notifies the KeyListener that a key was pressed.

keyReleased

public abstract void keyReleased (KeyEvent e)
Parameters e The key event that occurred.
Description Notifies the KeyListener that a key was released.

keyTyped

public abstract void keyTyped (KeyEvent e)
Parameters e The key event that occurred.
Description Notifies the KeyListener that a key was typed (pressed and released).

See Also

AWTEventMulticaster, EventListener, KeyEvent, KeyListener

21.20 MouseAdapter images

Description

The MouseAdapter class implements the methods of MouseListener with empty functions. It may be easier for you to extend MouseAdapter, overriding only those methods you are interested in, than to implement MouseListener and provide the empty functions yourself.

Class Definition

public abstract class java.awt.event.MouseAdapter
   extends java.lang.Object
   implements java.awt.event.MouseListener {

  // Instance Methods
  public void mouseClicked (MouseEvent e);
  public void mouseEntered (MouseEvent e);
  public void mouseExited (MouseEvent e);
  public void mousePressed (MouseEvent e);
  public void mouseReleased (MouseEvent e);
}

Instance Methods

mouseClicked

public void mouseClicked (MouseEvent e)
Parameters e The event that has occurred.
Description Does nothing. Override this function to be notified when the mouse button is clicked (pressed and released).

mouseEntered

public void mouseEntered (MouseEvent e)
Parameters e The event that has occurred.
Description Does nothing. Override this function to be notified when the user moves the mouse cursor into a component.

mouseExited

public void mouseExited (MouseEvent e)
Parameters e The event that has occurred.
Description Does nothing. Override this function to be notified when the moves the mouse cursor out of a component.

mousePressed

public void mousePressed (MouseEvent e)
Parameters e The event that has occurred.
Description Does nothing. Override this function to be notified when the mouse button is pressed.

mouseReleased

public void mouseReleased (MouseEvent e)
Parameters e The event that has occurred.
Description Does nothing. Override this function to be notified when the mouse button is released.

See Also

MouseEvent, MouseListener

21.21 MouseEvent images

Description

Mouse events are generated when the user moves and clicks the mouse.

Class Definition

public class java.awt.event.MouseEvent
   extends java.awt.event.InputEvent {

  // Constants
  public final static int MOUSE_CLICKED;
  public final static int MOUSE_DRAGGED;
  public final static int MOUSE_ENTERED;
  public final static int MOUSE_EXITED;
  public final static int MOUSE_FIRST;
  public final static int MOUSE_LAST;
  public final static int MOUSE_MOVED;
  public final static int MOUSE_PRESSED;
  public final static int MOUSE_RELEASED;

  // Constructors
  public MouseEvent (Component source, int id, long when, int modifiers, int x,
    int y, int clickCount, boolean popupTrigger);

  // Instance Methods
  public int getClickCount();
  public synchronized Point getPoint();
  public int getX();
  public int getY();
  public boolean isPopupTrigger();
  public String paramString();
  public synchronized void translatePoint (int x, int y);
}

Constants

MOUSE_CLICKED

public final static int MOUSE_CLICKED

An event type ID indicating a mouse click.

MOUSE_DRAGGED

public final static int MOUSE_DRAGGED

An event type ID indicating a mouse move with the button held down.

MOUSE_ENTERED

public final static int MOUSE_ENTERED

An event type ID indicating that a mouse entered a component.

MOUSE_EXITED

public final static int MOUSE_EXITED

An event type ID indicating that a mouse left a component.

MOUSE_FIRST

public final static int MOUSE_FIRST

Specifies the beginning range of mouse event ID values.

MOUSE_LAST

public final static int MOUSE_LAST

Specifies the ending range of mouse event ID values.

MOUSE_MOVED

public final static int MOUSE_MOVED

An event type ID indicating a mouse move.

MOUSE_PRESSED

public final static int MOUSE_PRESSED

An event type ID indicating a mouse button press.

MOUSE_RELEASED

public final static int MOUSE_RELEASED

An event type ID indicating a mouse button release.

Constructors

MouseEvent

public MouseEvent (Component source, int id, long when,
int modifiers, int x, int y, int clickCount, boolean
popupTrigger)
Parameters source The object that generated the event.
id The event type ID of the event.
when When the event occurred, in milliseconds from the epoch.
modifiers What modifier keys were pressed with this key.
x The horizontal location of the event.
y The vertical location of the event.
clickCount The number of times the mouse button has been clicked.
popupTrigger A flag indicating if this event is a popup trigger event.
Description Constructs a MouseEvent with the given characteristics.

Instance Methods

getClickCount

public int getClickCount()
Returns The number of consecutive mouse button clicks for this event.

getPoint

public synchronized Point getPoint()
Returns The location where the event happened.

getX

public int getX()
Returns The horizontal location where the event happened.

getY

public int getY()
Returns The vertical location where the event happened.

isPopupTrigger

public boolean isPopupTrigger()
Returns Returns true if this event is the popup menu event for the runtime system.

paramString

public String paramString()
Returns String with current settings of the MouseEvent.
Overrides ComponentEvent.paramString()
Description Helper method for toString() to generate string of current settings.

translatePoint

public synchronized void translatePoint (int x, int y)
Parameters x The horizontal amount of translation.
y The vertical amount of translation.
Description Translates the location of the event by the given amounts.

See Also

Component, ComponentEvent, InputEvent, MouseAdapter, MouseListener, Point

21.22 MouseListener images

Description

Objects that implement the MouseListener interface can receive non-motion oriented MouseEvent objects. Listeners must first register themselves with objects that produce events. When events occur, they are then automatically propagated to all registered listeners.

Interface Definition

public abstract interface java.awt.event.MouseListener
   extends java.util.EventListener {

  // Instance Methods
  public abstract void mouseClicked (MouseEvent e);
  public abstract void mouseEntered (MouseEvent e);
  public abstract void mouseExited (MouseEvent e);
  public abstract void mousePressed (MouseEvent e);
  public abstract void mouseReleased (MouseEvent e);
}

Interface Methods

mouseClicked

public abstract void mouseClicked (MouseEvent e)
Parameters e The key event that occurred.
Description Notifies the MouseListener that the mouse button was clicked (pressed and released).

mouseEntered

public abstract void mouseEntered (MouseEvent e)
Parameters e The key event that occurred.
Description Notifies the MouseListener that the mouse cursor has been moved into a component's coordinate space.

mouseExited

public abstract void mouseExited (MouseEvent e)
Parameters e The key event that occurred.
Description Notifies the MouseListener that the mouse cursor has been moved out of a component's coordinate space.

mousePressed

public abstract void mousePressed (MouseEvent e)
Parameters e The key event that occurred.
Description Notifies the MouseListener that the mouse button was pressed.

mouseReleased

public abstract void mouseReleased (MouseEvent e)
Parameters e The key event that occurred.
Description Notifies the MouseListener that the mouse button was released.

See Also

EventListener, MouseAdapter, MouseEvent

21.23 MouseMotionAdapter images

Description

The MouseMotionAdapter class implements the methods of MouseMotionListener with empty functions. It may be easier for you to extend MouseMotionAdapter, overriding only those methods you are interested in, than to implement MouseMotionListener and provide the empty functions yourself.

Class Definition

public abstract class java.awt.event.MouseMotionAdapter
   extends java.lang.Object
   implements java.awt.event.MouseMotionListener {

  // Instance Methods
  public void mouseDragged (MouseEvent e);
  public void mouseMoved (MouseEvent e);
}

Instance Methods

mouseDragged

public void mouseDragged (MouseEvent e)
Parameters e The event that has occurred.
Description Does nothing. Override this function to be notified when the mouse is dragged.

mouseMoved

public void mouseEntered (MouseEvent e)
Parameters e The event that has occurred.
Description Does nothing. Override this function to be notified when the mouse moves.

See Also

MouseEvent, MouseMotionListener

21.24 MouseMotionListener images

Description

Objects that implement the MouseMotionListener interface can receive motionoriented MouseEvent objects. Listeners must first register themselves with objects that produce events. When events occur, they are automatically propagated to all registered listeners.

Interface Definition

public abstract interface java.awt.event.MouseMotionListener
   extends java.util.EventListener {

  // Instance Methods
  public abstract void mouseDragged (MouseEvent e);
  public abstract void mouseMoved (MouseEvent e);
}

Interface Methods

mouseDragged

public abstract void mouseDragged (MouseEvent e)
Parameters e The key event that occurred.
Description Notifies the MouseMotionListener that the mouse has been dragged.

mouseMoved

public abstract void mouseMoved (MouseEvent e)
Parameters e The key event that occurred.
Description Notifies the MouseMotionListener that the mouse has been moved.

See Also

AWTEventMulticaster, EventListener, MouseEvent, MouseMotionAdapter

21.25 PaintEvent images

Description

The PaintEvent class represents the paint and update operations that the AWT performs on components. There is no PaintListener interface, so the only way to catch these events is to override paint(Graphics) and update(Graphics) in Component. This class exists so that paint events will get serialized properly.

Class Definition

public class java.awt.event.PaintEvent
   extends java.awt.event.ComponentEvent {

  // Constants
  public final static int PAINT;
  public final static int PAINT_FIRST;
  public final static int PAINT_LAST;
  public final static int UPDATE;

  // Constructor
  public PaintEvent (Component source, int id, Rectangle updateRect);

  // Instance Methods
  public Rectangle getUpdateRect();
  public String paramString();
  public void setUpdateRect (Rectangle updateRect);
}

Class Definition

public class java.awt.event.PaintEvent
        extends java.awt.event.ComponentEvent {

  // Constants
  public final static int PAINT;
  public final static int PAINT_FIRST;
  public final static int PAINT_LAST;
  public final static int UPDATE;

  //Constructor
  public PaintEvent (Component source, int id, Rectangle updateRect);

  // Instance Methods
  public Rectangle getUpdateRect();
  public String paramString();
  public void setUpdateRect (Rectangle updateRect);
}

Constants

PAINT

public final static int PAINT

The paint event type.

PAINT_FIRST

public final static int PAINT_FIRST

Specifies the beginning range of paint event ID values.

PAINT_LAST

public final static int PAINT_LAST

Specifies the ending range of paint event ID values.

UPDATE

public final static int UPDATE

The update event type.

Constructor

PaintEvent

public PaintEvent (Component source, ind id, Rectangle
updateRect)
Parameters source The source of the event.
id The event type ID.
g The rectangular area to paint.
Description Constructs a PaintEvent with the given characteristics.

Instance Methods

getUpdateRect

public Rectangle getUpdateRect()
Returns The rectangular area that needs painting.

paramString

public String paramString()
Returns String with current settings of the PaintEvent.
Overrides ComponentEvent.paramString()
Description Helper method for toString() to generate string of current settings.

setUpdateRect

public void setUpdateRect (Rectangle updateRect)
Parameters updateRect The rectangular area to paint.
Description Changes the rectangular area that this PaintEvent will paint.

See Also

Component, ComponentEvent, Graphics

21.26 TextEvent images

Description

Text events are generated by text components when their contents change, either programmatically or by a user typing.

Class Definition

public class java.awt.event.TextEvent
   extends java.awt.AWTEvent {

  // Constants
  public final static int TEXT_FIRST;
  public final static int TEXT_LAST;
  public final static int TEXT_VALUE_CHANGED;

  // Constructors
  public TextEvent (Object source, int id);

  // Instance Methods
  public String paramString();
}

Constants

TEXT_FIRST

public final static int TEXT_FIRST

Specifies the beginning range of text event ID values.

TEXT_LAST

public final static int TEXT_LAST

Specifies the ending range of text event ID values.

TEXT_VALUE_CHANGED

public final static int TEXT_VALUE_CHANGED

The only text event type; it indicates that the contents of something have changed.

Constructors

TextEvent

public TextEvent (Object source, int id)
Parameters source The object that generated the event.
id The type ID of the event.
Description Constructs a TextEvent with the given characteristics.

Instance Methods

paramString

public String paramString()
Returns String with current settings of the TextEvent.
Overrides AWTEvent.paramString()
Description Helper method for toString() to generate string of current settings.

See Also

AWTEvent, TextListener

21.27 TextListener images

Description

Objects that implement the TextListener interface can receive TextEvent objects. Listeners must first register themselves with objects that produce events. When events occur, they are then automatically propagated to all registered listeners.

Interface Definition

public abstract interface java.awt.event.TextListener
   extends java.util.EventListener {

  // Interface Methods
  public abstract void textValueChanged (TextEvent e);
}

Interface Methods

textValueChanged

public abstract void textValueChanged (TextEvent e)
Parameters e The text event that occurred.
Description Notifies the TextListener that an event occurred.

See Also

AWTEventMulticaster, EventListener, TextEvent

21.28 WindowAdapter images

Description

The WindowAdapter class implements the methods of WindowListener with empty functions. It may be easier for you to extend WindowAdapter, overriding only those methods you are interested in, than to implement WindowListener and provide the empty functions yourself.

Class Definition

public abstract class java.awt.event.WindowAdapter
   extends java.lang.Object
   implements java.awt.event.WindowListener {

  // Instance Methods
  public void windowActivated (WindowEvent e);
  public void windowClosed (WindowEvent e);
  public void windowClosing (WindowEvent e);
  public void windowDeactivated (WindowEvent e);
  public void windowDeiconified (WindowEvent e);
  public void windowIconified (WindowEvent e);
  public void windowOpened (WindowEvent e);
}

Instance Methods

windowActivated

public void windowActivated (WindowEvent e)
Parameters e The event that has occurred.
Description Does nothing. Override this function to be notified when a window is activated.

windowClosed

public void windowClosed (WindowEvent e)
Parameters e The event that has occurred.
Description Does nothing. Override this function to be notified when a window is closed.

windowClosing

public void windowClosing (WindowEvent e)
Parameters e The event that has occurred.
Description Does nothing. Override this function to be notified when a window is in the process of closing.

windowDeactivated

public void windowDeactivated (WindowEvent e)
Parameters e The event that has occurred.
Description Does nothing. Override this function to be notified when a window is deactivated.

windowDeiconified

public void windowDeiconified (WindowEvent e)
Parameters e The event that has occurred.
Description Does nothing. Override this function to be notified when an iconified window is restored.

windowIconified

public void windowIconified (WindowEvent e)
Parameters e The event that has occurred.
Description Does nothing. Override this function to be notified when a window is iconified (minimized).

windowOpened

public void windowOpened (WindowEvent e)
Parameters e The event that has occurred.
Description Does nothing. Override this function to be notified when a window is opened.

See Also

WindowEvent, WindowListener

21.29 WindowEvent images

Description

Window events are generated when a window is opened, closed, iconified, or deiconified.

Class Definition

public class java.awt.event.WindowEvent
   extends java.awt.event.ComponentEvent {

  // Constants
  public final static int WINDOW_ACTIVATED;
  public final static int WINDOW_CLOSED;
  public final static int WINDOW_CLOSING;
  public final static int WINDOW_DEACTIVATED;
  public final static int WINDOW_DEICONIFIED;
  public final static int WINDOW_FIRST;
  public final static int WINDOW_ICONIFIED;
  public final static int WINDOW_LAST;
  public final static int WINDOW_OPENED;

  // Constructors
  public WindowEvent (Window source, int id);

  // Instance Methods
  public Window getWindow();
  public String paramString();
}

Constants

WINDOW_ACTIVATED

public final static int WINDOW_ACTIVATED

Event type ID indicating the window has been activated, brought to the foreground.

WINDOW_CLOSED

public final static int WINDOW_CLOSED

Event type ID indicating the window has closed.

WINDOW_CLOSING

public final static int WINDOW_CLOSING

Event type ID indicating the window is closing.

WINDOW_DEACTIVATED

public final static int WINDOW_DEACTIVATED

Event type ID indicating the window has been deactivated, placed in the background.

WINDOW_DEICONIFIED

public final static int WINDOW_DEICONIFIED

Event type ID indicating the window has been restored from an iconified state.

WINDOW_FIRST

public final static int WINDOW_FIRST

Specifies the beginning range of window event ID values.

WINDOW_ICONIFIED

public final static int WINDOW_ICONIFIED

Event type ID indicating the window has been iconified (minimized).

WINDOW_LAST

public final static int WINDOW_LAST

Specifies the ending range of window event ID values.

WINDOW_OPENED

public final static int WINDOW_OPENED

Event type ID indicating the window has opened.

Constructors

WindowEvent

public WindowEvent (Window source, int id)
Parameters source The object that generated the event.
id The event type ID of the event.
Description Constructs a WindowEvent with the given characteristics.

Instance Methods

getWindow

public Window getWindow()
Returns The window that generated this event.

paramString

public String paramString()
Returns String with current settings of the WindowEvent.
Overrides ComponentEvent.paramString()
Description Helper method for toString() to generate string of current settings.

See Also

ComponentEvent, Window, WindowAdapter, WindowListener

21.30 WindowListener images

Description

Objects that implement the WindowListener interface can receive WindowEvent objects. Listeners must first register themselves with objects that produce events. When events occur, they are then automatically propagated to all registered listeners.

Interface Definition

public abstract interface java.awt.event.WindowListener
   extends java.util.EventListener {

  // Instance Methods
public abstract void windowActivated (WindowEvent e);
  public abstract void windowClosed (WindowEvent e);
  public abstract void windowClosing (WindowEvent e);
  public abstract void windowDeactivated (WindowEvent e);
  public abstract void windowDeiconified (WindowEvent e);
  public abstract void windowIconified (WindowEvent e);
  public abstract void windowOpened (WindowEvent e);
}

Interface Methods

windowActivated

public abstract void windowActivated (WindowEvent e)
Parameters e The event that occurred.
Description Notifies the WindowListener that a window has been activated.

windowClosed

public abstract void windowClosed (WindowEvent e)
Parameters e The event that occurred.
Description Notifies the WindowListener that a window has closed.

windowClosing

public abstract void windowClosing (WindowEvent e)
Parameters e The event that occurred.
Description Notifies the WindowListener that a window is closing.

windowDeactivated

public abstract void windowDeactivated (WindowEvent e)
Parameters e The event that occurred.
Description Notifies the WindowListener that a window has been deactivated.

windowDeiconified

public abstract void windowDeiconified (WindowEvent e)
Parameters e The event that occurred.
Description Notifies the WindowListener that a window has been restored from an iconified state.

windowIconified

public abstract void windowIconified (WindowEvent e)
Parameters e The event that occurred.
Description Notifies the WindowListener that a window has iconified (minimized).

windowOpened

public abstract void windowOpened (WindowEvent e)
Parameters e The event that occurred.
Description Notifies the WindowListener that a window has opened.

See Also

AWTEventMulticaster, EventListener, Window, WindowAdapter, WindowEvent

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