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Button

Name

Button

[Graphic: Figure from the text]

Description

The Button is the familiar labeled button object. It inherits most of its functionality from Component. For example, to change the font of the Button, you would use Component's setFont() method. The Button sends java.awt.event.ActionEvent objects to its listeners when it is pressed.

Class Definition

public class java.awt.Button
    extends java.awt.Component {
  
  // Constructors
  public Button();
  public Button (String label);
  
  // Instance Methods
  public void addActionListener (ActionListener l); (New)
  public void addNotify();
  public String getActionCommand(); (New)
  public String getLabel();
  public void removeActionListener (ActionListener l); (New)
  public void setActionCommand (String command); (New)
  public synchronized void setLabel (String label);
  
  // Protected Instance Methods
  protected String paramString();
  protected void processActionEvent (ActionEvent e); (New)
  protected void processEvent (AWTEvent e); (New)
}

Constructors

Button

public Button()

Description

Constructs a Button object with no label.

public Button (String label)

Parameters

label

The text for the label on the button

Description

Constructs a Button object with text of label.

Instance Methods

addActionListener

public void addActionListener (ActionListener l) (New)

Parameters

l

An object that implements the ActionListener interface.

Description

Add a listener for the action event.

addNotify

public void addNotify()

Overrides

Component.addNotify()

Description

Creates Button's peer.

getActionCommand

public String getActionCommand() (New)

Returns

Current action command string.

Description

Returns the string used for the action command.

getLabel

public String getLabel()

Returns

Text of the Button's label.

removeActionListener

public void removeActionListener (ActionListener l) (New)

Parameters

l

One of this Button's ActionListeners.

Description

Remove an action event listener.

setActionCommand

public void setActionCommand (String command) (New)

Parameters

command

New action command string.

Description

Specify the string used for the action command.

setLabel

public synchronized void setLabel (String label)

Parameters

label

New text for label of Button.

Description

Changes the Button's label to label.

Protected Instance Methods

paramString

protected String paramString()

Returns

String with current settings of Button.

Overrides

Component.paramString()

Description

Helper method for toString() used to generate a string of current settings.

processActionEvent

protected void processActionEvent (ActionEvent e) (New)

Parameters

e

The action event to process.

Description

Action events are passed to this method for processing. Normally, this method is called by processEvent().

processEvent

protected void processEvent (AWTEvent e) (New)

Parameters

e

The event to process.

Description

Low level AWTEvents are passed to this method for processing.

See Also

ActionListener, Component, String


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