High frequency UI update - Android

Question

I want to make 8 squares change colors between red/black periodically. I acomplish this using timer.schedule with period time in milliseconds and it work

BUT then I realized that I need to use small time between this transitions (example nanoseconds).

To accomplish that I wrote this code:

timerTask = new TimerTask() {
    public void run() {
        handler.post(new Runnable() {
            public void run(){

                //CODE OF THE TASK.

            }
        });
    }
};


//To make schedule this task in 5 nanoseconds I use this!
exec = new ScheduledThreadPoolExecutor(1);
exec.scheduleAtFixedRate(timerTask, 0, 5, TimeUnit.NANOSECONDS);

But when I run this, the UI is not updating (seems to be stuck), but in logcat, all the logs are printing very fast. How can I achieve to make a task periodically x nanoseconds?

Answer 1

The entire Android UI runs at 60Hz- 60 updates per second. This means the minimum time between redraws is 16 ms. You cannot run it at a higher framerate. Nor are human eyes capable of seeing changes at a much higher frequency than that.

iOS and most video game consoles also work on a 60 Hz refresh rate. You'd find very few to no systems that go faster.

I'm not sure what exactly you're trying to accomplish, but I'm fairly certain you're trying to do it the wrong way.

ALSO: I notice your timer task posts to a handler. That means your timer task is going to tell the main thread to run something, and the timer task is running in nanoseconds. YOu're basically going to choke your main thread full of "run this task" messages, then eventually crash with an OOM error when the event queue becomes so massive it can't add any more (which may take several minutes), because there's no way you're processing them fast enough with the thread switching overhead.