android assign a drawable dynamicaly to a imageview

Question

I have an array of drawables, that I would like to change by my own timer to a imageview. (i tried the other option with xml and setBackgroundResource, but does not work for me as I have hundret of pics and always got memory problem as it looks android assign already the whole memory for all pics at once. (just in this demo i shorted it to 4 images)

Ok, so first i make my array

private static int[] draws = {
     R.drawable.frankiearmevor_0001, 
     R.drawable.frankiearmevor_0002, 
     R.drawable.frankiearmevor_0003, 
     R.drawable.frankiearmevor_0002 
 };

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);

    imgView = (ImageView) findViewById(R.id.fredi);

    // create timer        
    Timer updateProgressTimer = new Timer();
    updateProgressTimer.scheduleAtFixedRate(new TimerTask() {
        @Override
        public void run() {
            myloop();
        }
    }, 0, 150);
}

int mycounter;
public void myloop()
{
    mycounter++;
    if (mycounter > 4) mycounter = 1;
    imgView.setImageResource(draws[mycounter-1]);
    String hallo; hallo = "now: "+mycounter;
    Log.d("1",hallo);

}

when I assign only a fixed image: imgView.setImageResource(draws[2]); it shows that fine and I see also my thread is logged fine, but when I exchange the fixed resource draws[2] into a dynamic draws[mycounter-1] .. i just get a black screen, no error, nothing.

what to do, so i will show the images :)

thx chris

EDIT: 22. August:

I tried now with the comment I got, it compiles fine, but somehow there is an error i guess.. it crash:

    imgView = (ImageView) findViewById(R.id.fredi);

    Timer updateProgressTimer = new Timer();

    updateProgressTimer.scheduleAtFixedRate(new TimerTask() 
    {
        @Override
        public void run() 
        {
            //myloop();
            imgView.post (new Runnable() 
            {

                public void run() 
                {
                    mycounter++;
                    if (mycounter > 10) mycounter = 1;
                    imgView.setImageResource(draws[1]);
                    //imgView.invalidate();
                    String hallo; hallo = "now: "+mycounter;
                    Log.d("1",hallo);
                 }

            });
        }
    }, 0, 150);

Answer 1

The ImageView update should happen on the UI Thread...

Refer this answer. The TimerTask runs on a different thread, so you've to use the imgView.post() to update the UI Component.

Are you sure you need to update the Component every 150ms? That's very expensive.

Good Luck.