dcsimg
TODAY'S HEADLINES  |   ARTICLE ARCHIVE  |   FORUMS  |   TIP BANK
Browse DevX
Sign up for e-mail newsletters from DevX


Tip of the Day
Language: Java
Expertise: Advanced
Jun 1, 2005

WEBINAR:

On-Demand

Building the Right Environment to Support AI, Machine Learning and Deep Learning


Capturing the ESCAPE Key Event

Consider a scenario where a dialog is launched from a panel which itself was launched by another panel. It's very tedious to get the dialog disposed when the ESCAPE key is pressed. The code segment below makes it easy to capture the ESCAPE key event, irrespective of the hierarchy, and performs the designated action.

 //Has to be final because this instance is required in the inner class
    final UpdateCustomerData updationPanel = new UpdateCustomerData(mainPanel);
    //Setting the size
    updationPanel.setSize(400,150);
    //Creating an input map of the Root Pane
    InputMap map = updationPanel.getRootPane().getInputMap(
		JComponent.WHEN_ANCESTOR_OF_FOCUSED_COMPONENT );
    //Adding the key that needs to be captured
    map.put(KeyStroke.getKeyStroke(KeyEvent.VK_ESCAPE, 0), "cancel" );
    ActionMap actionMap = updationPanel.getRootPane().getActionMap();
    //Creating the action that needs to be executed when the key is pressed
    Action close = new AbstractAction() {
	public void actionPerformed(ActionEvent ae)
	{
	    updationPanel.dispose();
	}
    };
    actionMap.put( "cancel", close);
    //Displaying the Panel
    updationPanel.setVisible(true);
updationPanel is the panel that will be affected by the ESCAPE key event here.
MS Sridhar
 
Thanks for your registration, follow us on our social networks to keep up-to-date