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POResume to SurfaceView shows black screen
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copied!<p>All is ok, when I have started my application. But when I go to the next activity and come back the SurfaceView it looks like <code>black</code>. When I debug, I can see the lines that need to draw on the canvas running but nothing shows up.<br> Here is my code:</p> <pre><code>public class DrawView extends SurfaceView implements Runnable { Thread thread = null; SurfaceHolder holder; Bitmap background; Canvas canvas; Matrix matrixUP = new Matrix(); Matrix matrixDOWN = new Matrix(); boolean ok = false; public DrawView(Context context) { super(context); holder = getHolder(); } public void run() { while(ok) { if(!holder.getSurface().isValid()) { continue; } watch_hand = Bitmap.createScaledBitmap(watch_hand, width/4, height/6, false); watch_hand_down = Bitmap.createScaledBitmap(watch_hand_down, width/4, height/6, false); background = BitmapFactory.decodeResource(getResources(), R.drawable.needles); background = Bitmap.createScaledBitmap(background, width, height/2+20, false); canvas = holder.lockCanvas(); matrixUP.setTranslate(CENTER_X - watch_hand.getWidth()/2, height/4 - watch_hand.getHeight() - 40); matrixUP.preRotate((float) degreUP , watch_hand.getWidth()/2 , watch_hand.getHeight()-10); matrixDOWN.setTranslate(CENTER_X - watch_hand_down.getWidth()/2, height/2 - watch_hand_down.getHeight() - 20); matrixDOWN.preRotate((float) degreDOWN , watch_hand_down.getWidth()/2 , 10); canvas.drawARGB(255, 255, 255, 255); canvas.drawBitmap(background, 0, 0, null); canvas.drawBitmap(watch_hand, matrixUP, null); canvas.drawBitmap(watch_hand_down, matrixDOWN, null); holder.unlockCanvasAndPost(canvas); } } public void pause() { ok = false; while(true) { try { thread.join(); }catch (InterruptedException e) { e.printStackTrace(); } break; } thread = null; } public void resume() { ok = true; thread = new Thread(this); thread.start(); } } </code></pre> <p>as you see I'm using a resume and pause function. They are called from the onCreate. Why is it happening and how can I fix this?</p> <p>Thanks!</p>

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