KeyListener CMD+W

[Alexander Haid]

Hi all!

I am programming my own plugin in java. I am using a JDialog window to
display all the buttons, etc.
 
Now I wanted to add a small, but useful function to my plugin: that the user
is able to close the plugin dialog with the common key shortcuts - under mac
osx CMD+w or windows CTRL+w.

Already read the programming example about Key Listeners
(http://rsbweb.nih.gov/ij/plugins/key-listener.html). But could not figure
out how to fetch combinded key-strokes like the ones I wannt to act on? Can
someone tell me how to do that the best way?

Thanks,
 - alex

[dscho]

Hi Alex,

On Mon, 5 Oct 2009, Alexander Haid wrote:

> I am programming my own plugin in java. I am using a JDialog window to
> display all the buttons, etc.
>
> Now I wanted to add a small, but useful function to my plugin: that the
> user is able to close the plugin dialog with the common key shortcuts -
> under mac osx CMD+w or windows CTRL+w.
>
> Already read the programming example about Key Listeners
> (http://rsbweb.nih.gov/ij/plugins/key-listener.html). But could not figure
> out how to fetch combinded key-strokes like the ones I wannt to act on? Can
> someone tell me how to do that the best way?

This is how we do the things in Fiji:

http://pacific.mpi-cbg.de/cgi-bin/gitweb.cgi?p=fiji.git;a=commitdiff;h=3d1569da99ca90ca6c3d6721f7afec069c9c52c6

In short, we use this method:

-- snip --
       /**
        * Add a keyboard accelerator to a container.
        *
        * This method adds a keystroke to the input map of a container that
        * sends an action event with the given source to the given listener.
        */
        public static void addAccelerator(final Component source,
                       final JComponent container,
                       final ActionListener listener, int key, int modifiers) {
                container.getInputMap(container.WHEN_IN_FOCUSED_WINDOW)
                       .put(KeyStroke.getKeyStroke(key, modifiers), source);
                if (container.getActionMap().get(source) != null)
                        return;
                container.getActionMap().put(source,
                                new AbstractAction() {
                        public void actionPerformed(ActionEvent e) {
                                if (!source.isEnabled())
                                        return;
                                ActionEvent event = new ActionEvent(source,
                                        0, "Accelerator");
                                listener.actionPerformed(event);
                        }
                });
        }
-- snap --

and we use it like this (just after the call to pack(), but you can place
it anywhere, really):

-- snip --
                       addAccelerator(cancel, (JComponent)contentPane, this,
                               KeyEvent.VK_W, Toolkit.getDefaultToolkit()
                                       .getMenuShortcutKeyMask());
-- snap --

As you probably guessed, the "cancel" variable refers to a JButton doing
the job, but it really can be any component that the ActionListener knows
should trigger the "cancel".

Feel free to use the code as you see fit (i.e. this is my code and I
explicitely give up GPLv2 on it, just in case anybody thinks this is
untrivial enough to enforce a license or some such).

Ciao,
Dscho

[dscho]

Hi,

On Mon, 5 Oct 2009, Johannes Schindelin wrote:

> On Mon, 5 Oct 2009, Alexander Haid wrote:
>
> > I am programming my own plugin in java. I am using a JDialog window to
> > display all the buttons, etc.
>
> [... some code we have in Fiji...]

FWIW this code _only_ works with Swing containers.  Just in case anybody
thought of using this in AWT dialogs: it does not work, as there is no
input or action map in AWT containers.

Ciao,
Dscho