How to detect ctrl-f in my SWT application

java event-handling keyboard-shortcuts swt
mchr picture mchr · Apr 30, 2011 · Viewed 21.2k times · Source

I have written an SWT UI which has a primary function of displaying text in a StyledText control. I want to add a handler for Ctrl+F so that when that shortcut is pressed the focus is set to a search box. I have tried using the following code to detect the keypress.

sWindow = new Shell();
...
sWindow.getDisplay().addFilter(SWT.KeyDown, new Listener()
{
  @Override
  public void handleEvent(Event e)
  {
    System.out.println("Filter-ctrl: " + SWT.CTRL);
    System.out.println("Filter-mask: " + e.stateMask);
    System.out.println("Filter-char: " + e.character);
  }
});

I was expecting that when I pressed Ctrl+f I would see the following output:

Filter-ctrl: 262144
Filter-mask: 262144
Filter-char: f

However, in practice I actually see the following.

Filter-ctrl: 262144
Filter-mask: 262144
Filter-char: <unprintable char - displayed as a box in eclipse console>

I have two questions:

  • Is Display.addFilter(...) the best way to add a global shortcut? I tried Display.addListener(...) but this didn't receive any events at all.
  • Why don't I get the pressed character when I'm holding down Ctrl? When I hold down alt or shift I get the expected mask and the pressed character.

Answer

Favonius picture Favonius · Apr 30, 2011

Is Display.addFilter(...) the best way to add a glbal shortcut? I tried Display.addListener(...) but this didn't receive any events at all.

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