Question

I have a really simple custom animation that I am trying to run, and I can’t seem to figure out where I have messed up, though I suspect it has something to do with multithreading.

Basically, when a fling occurs I need to redraw the canvas over and over a bunch of times.

This is part of what I have right now:

        gestureDetector = new GestureDetector(NamePickerActivity.this,
                new GestureDetector.SimpleOnGestureListener() {
                    @Override
                    public boolean onFling(MotionEvent arg0,
                            MotionEvent arg1, float arg2, float arg3) {

                        final long startTime = System.currentTimeMillis();
                        Thread thread = new Thread(new Runnable() {
                            @Override
                            public void run() {
                                while (System.currentTimeMillis()
                                        - startTime < 2000) {
                                    System.out.println("running...");

                                    // incrementing this causes the draw to
                                    // occur differently
                                    pathCount++;
                                    invalidate();
                                }

                                System.out.println("done...");
                            }
                        });

                        thread.run();

                        return true;
                    }

                    @Override
                    public boolean onDown(MotionEvent e) {
                        return true;
                    }
                });

At this point, I’d like to have it continue to redraw for a couple seconds and then be done.

Does anyone know what I’ve done wrong here? If so, can you explain it?

Answer 1

A thread is started with thread.start(), not thread.run(). thread.run() just calls the run method sequentially on the main thread.