Ndtyjky

Having a "next" Button, when I press keyboard enter key with the button selected, the widgetSelected event of the buton is being repeatedly called once and once and doing a super fast next. It's exactly the behaviour I want, but only happens with keyboard enter key. I want to have that behaviour with mouse click when holding the click. When trying to do the same with the mouse click, the behaviour is not the same, it only makes one event call, and when the click is end (UP).

How to simulate the same behaviour with the mouse click?

I tryed it doing this, but it blocks the UI (can't understand why) and mouseUp is never being called, it blocks forever in the while

    button.addMouseListener(new MouseAdapter() {

        boolean mouseDown;

        @Override

        public void mouseDown(MouseEvent e) {

            System.out.println("mouseDown");

            mouseDown = true;

            Display.getDefault().asyncExec(new Runnable() {

                @Override

                public void run() {

                    while (mouseDown) {

                        System.out.println("Doing next in mouseDown");

                        next(composite, label_1);

                        synchronized(this){

                            try {

                                wait(100);

                            } catch (InterruptedException e) {

                                e.printStackTrace();

                            }

                        }

                    }

                }

            });



        }

        @Override

        public void mouseUp(MouseEvent e) {

            System.out.println("mouseUp");

            mouseDown = false;

        }

    }); 

The Runnable you give to asyncExec runs in the UI thread. You must never do any sort of wait in the UI thread as that will block the UI until it completes.

So you cannot run a loop like this as it just blocks the UI. Since the loop never returns to the main SWT readAndDispatch loop no UI actions are done.

Instead use the timerExec method of Display to schedule a Runnable to run after a given interval. This runnable should do one step of the action and use timerExec to schedule the next step later.

I remember there was another question a few days ago regarding a long mouse click behaviour but I can't find it anymore. I put this code based on greg-449 solution to use timerExec method, after my failed attempts to use asyncExec in the UI thread. :)

    button.addMouseListener(new MouseAdapter() {

        boolean mouseDown;



        @Override

        public void mouseDown(MouseEvent e) {

            mouseDown = true;

            Display.getCurrent().timerExec(1000, () -> {

                if (mouseDown) {

                    button.notifyListeners(SWT.Selection, new Event());

                    button.notifyListeners(SWT.MouseDown, new Event());

                }

            });

        }



        @Override

        public void mouseUp(MouseEvent e) {

            mouseDown = false;

        }

    });



    button.addSelectionListener(SelectionListener.widgetSelectedAdapter(

            e -> System.out.println("Do next")));