Button Methods

Buttons are simple objects. Most of the time all you need to do is add them to the layout and add an ActionListener. The following methods are also available:

public void   addNotify()
public String getLabel()
public void   setLabel(String label)
public void   setActionCommand(String command)
public String getActionCommand()
public void   addActionListener(ActionListener l)
public void   removeActionListener(ActionListener l)
addNotify() creates the Button's peer object, that is the native widget that has the appearance of a Windows button or a Mac button or a Motif button or whatever. It is extremely rare to call this directly.

The getLabel() and setLabel(String s) methods allow you to retrieve and change the text of the button while the applet is running. Given a Button b, here is how they might be used

String s = b.getLabel();
b.setLabel("Here's the new label");

Note that despite the suggestive name, getLabel() returns a String, not a Label.

The setActionCommand() and getActionCommand() methods modify the command string sent along with the ActionEvent. By default this is the label of the button, but it can be changed. For instance, you could use this as a way to pass the number of times the BeepApplet should beep

Finally addActionListener() registers another object as one which should receive ActionEvents fired by the Button. removeActionListener() deregisters the ActionListener object so it will no longer receive action events fired by this Button.

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Copyright 1997, 1998, 2002 Elliotte Rusty Harold
Last Modified July 10, 2002