Creating a custom modal dialog for a Swing applet / application

Question

I\'m writing a Swing application that needs to function either as an applet in a browser or as a standalone application, i.e. it may be contained in either a JFrame or a JApplet

Answer 1

Take a look at JDialog. If you set it modal it will run its own event processing to keep the GUI up to date, while capturing mouse and keyboard events for its own use.

I've looked at the code it uses and it's really not something you want to try to reinvent.

If you run it non modal, you 'll probably need to add a listener to be called when it finally closes. That is done with addWindowListener and a WindowAdapter that overrides windowClosing.

As for the owner parameter for the constructor, I use

    Window w = (Window) SwingUtilities.getAncestorOfClass(Window.class, comp);

where comp is some visible component.

It works because there is always a top level Window, whether running as an applet or application.

Answer 2

Here interesting method for showing frames as modal to specified owner is described: Show the given frame as modal to the specified owner

However, start() method of class EventPump should be modified in such way:

protected void start() throws Exception
{
    Class<?> cl = Class.forName("java.awt.Conditional");
    Object conditional = Proxy.newProxyInstance(cl.getClassLoader(), new Class[] { cl }, this);

    ThreadGroup threadGroup = Thread.currentThread().getThreadGroup();
    String name = Thread.currentThread().getName();
    EventQueue eventQueue = Toolkit.getDefaultToolkit().getSystemEventQueue();

    Constructor constructor = Class.forName("java.awt.EventDispatchThread").
            getDeclaredConstructor(ThreadGroup.class, name.getClass(), eventQueue.getClass());
    constructor.setAccessible(true);
    Object eventDispatchThread = constructor.newInstance(threadGroup, name, eventQueue);

    Method pumpMethod = eventDispatchThread.getClass().getDeclaredMethod("pumpEvents", cl);
    pumpMethod.setAccessible(true);
    pumpMethod.invoke(eventDispatchThread, conditional);
}