Question

What I have is a seekbar which is controlled by buttons rather than a slider using set/get progress.

I’m trying to get the seekbar progress to increase when a user presses a button and then stop increasing when they lift off the button. I have an onkey listener the detects up and down. I’m just not sure where to put the setprogress part, if I put a loop in on ACTION_DOWN, it’s then looping rather than detecting ACTION_UP the same seems to happen if I have a while loop for ACTION_DOWN.

I think I may also have to set refreshDraweableState, but I’ve not had much look with that either.

Potentially i’m trying to mess with seekbars too much but I’d appreciate any help/advice. Thanks!

This is my keylistner which is where I have been mostly messing about.

public boolean onKey(View view, int keyCode, KeyEvent event) {
    builder.setLength(0);
    switch (event.getAction()){
        case KeyEvent.ACTION_DOWN:
            builder.append(event.getKeyCode());
            String text = builder.toString();
            Log.w("seekbar", text);
            textView.setText(text);
            while (sk.getProgress() < 100){
                sk.setProgress(sk.getProgress()+1);
                sk.refreshDrawableState();
                try {
                    Thread.sleep(50);
                } catch (InterruptedException e) {
                    break;
                }
            }
            break;
        case KeyEvent.ACTION_UP:
            break;
    }
    return true;
}

}

Answer 1

You need to be able to stop your while loop in the ACTION_DOWN even, otherwise it will just keep going until it reaches 99.

Also your while loop blocks the UI thread so I would put it in a new thread (not sure how to do that on plain Android, I use Mono for Android), and either stop that thread when the ACTION_UP event occurs, or put another check in your while loop that breaks it.

In Mono for Android that would be done somewhat like this:

public bool OnKey(View view, int keyCode, KeyEvent e)
{
    switch(e.Action)
    {
        case KeyEventAction.Down:
            Start();
        break;
        case KeyEventAction.Up:
            Stop();
        break;
    }
}

private volatile bool _shouldStop;

public void IncreaseProgress()
{
    while (!_shouldStop && sk.Progress < 100)
    {
        //Working
        RunOnUiThread(() => {
            sk.Progress = sk.Progress+1;
            sk.RefreshDrawableState();
        });
        Thread.Sleep(50);
    }
    //Terminating
}

public void Start()
{
    _shouldStop = false;
    Thread workerThread = new Thread(IncreaseProgress);
    workerThread.Start();
}

public void Stop()
{
    _shouldStop = true;
    workerThread.Stop();
}