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Groups > comp.lang.java.gui > #5204

Re: Passing KeyEvent upward

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On 23/07/2012 01:09, Adam Beneschan allegedly wrote:
> Hi,
> 
> I'm trying to learn how to program in Java and use some of the GUI features..  Here's something I'm trying to do but haven't succeeded at yet.
> 
> I have a text window (JTextPane) object, and I want to set things up so that when a certain something happens, a popup menu (JPopupMenu) will come up.  But I'd like it so that if the user presses a key, the key is handled just as if the menu hadn't come up--that is, the key-press event will be handled by the JTextPane (or is it the associated document?) as if the user had typed that key into the document.  I've already set up a MenuKeyListener for the popup menu that recognizes the KeyEvent and calls menu.setVisible(false) to get rid of the menu.  So far, so good.  But I don't know how to get the KeyEvent propagated to the text window.  I've tried getKeyListeners() on the JTextPane and then calling the keyTyped explicitly on each listener.  No good--the only listener it found was one I had added myself for debugging.  I also tried textPane.getInputContext().dispatchEvent(e) on the KeyEvent; that didn't do what I wanted either (seemed to have no effect).
> 
> Any thoughts?  I haven't found anything else to try.
> 
> Thanks,
> 
>                            -- Adam

The following appears to be working, although not necessarily optimal:

package scratch;

import java.awt.EventQueue;
import java.awt.event.KeyEvent;
import javax.swing.BorderFactory;
import javax.swing.JFrame;
import javax.swing.JPopupMenu;
import javax.swing.JTextArea;

public class ScratchUI {

    public static void main( String[] args ) {
        EventQueue.invokeLater( new Runnable(){
            public void run(){
                JFrame f = new JFrame("Gah");
                f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

                JTextArea c = new Area();
                c.setColumns(40);
                c.setRows(10);
                c.setBorder( BorderFactory.createCompoundBorder(
                    BorderFactory.createEmptyBorder(10,20,10,20),
                    BorderFactory.createTitledBorder("Type here:")
                ) );

                f.getContentPane().add( c );
                f.pack();
                f.setLocationRelativeTo(null);
                f.setVisible(true);
            }
        } );
    }

    static boolean isShowMenuEvent( KeyEvent e ){
        return ! e.isConsumed()
            && e.getID() == KeyEvent.KEY_PRESSED
            && (e.getModifiers() == 0 || e.getModifiersEx() ==
KeyEvent.SHIFT_DOWN_MASK)
            && e.getKeyCode() == KeyEvent.VK_A
        ;
    }

    static final class Area
    extends JTextArea
    {
        private JPopupMenu menu;

        protected JPopupMenu createMenu(){
            JPopupMenu ret = new JPopupMenu();
            ret.add("Blah");
            ret.add("Bleh");
            ret.addSeparator();
            ret.add("Uh.");

            ret.setFocusable(false);
            ret.setFocusTraversalKeysEnabled(false);

            return ret;
        }

        private void toggleShowMenu( KeyEvent e ){
            if( menu == null ){
                menu = createMenu();
            }

            if( menu.isShowing() ){
                menu.setVisible(false);
            }
            else {
                //position??
                menu.show(e.getComponent(), e.getComponent().getX() +
10, e.getComponent().getY() + 50);
            }
        }

        @Override
        protected void processKeyEvent( KeyEvent e ) {
            if( isShowMenuEvent(e) ){
                toggleShowMenu(e);
            }
            super.processKeyEvent(e);
        }
    }
}


HTH,

-- 
DF.

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Thread

Passing KeyEvent upward Adam Beneschan <adam@irvine.com> - 2012-07-22 16:09 -0700
  Re: Passing KeyEvent upward markspace <-@.> - 2012-07-22 17:26 -0700
    Re: Passing KeyEvent upward markspace <-@.> - 2012-07-22 17:39 -0700
    Re: Passing KeyEvent upward Adam Beneschan <adam@irvine.com> - 2012-07-23 21:15 -0700
      Re: Passing KeyEvent upward markspace <-@.> - 2012-07-23 23:08 -0700
  Re: Passing KeyEvent upward "John B. Matthews" <nospam@nospam.invalid> - 2012-07-22 21:32 -0400
  Re: Passing KeyEvent upward Roedy Green <see_website@mindprod.com.invalid> - 2012-07-23 23:46 -0700
  Re: Passing KeyEvent upward Knute Johnson <nospam@rabbitbrush.frazmtn.com> - 2012-07-24 13:15 -0700
    Re: Passing KeyEvent upward Adam Beneschan <adam@irvine.com> - 2012-07-24 21:08 -0700
      Re: Passing KeyEvent upward markspace <-@.> - 2012-07-24 22:50 -0700
  Re: Passing KeyEvent upward Daniele Futtorovic <da.futt.news@laposte-dot-net.invalid> - 2012-07-25 00:32 +0200

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