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PODrawing a line in a class which extends "Activity'
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  1. PODrawing a line in a class which extends "Activity'
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    copied!<p>I have an ImageView loading a picture in my Activity and want to draw some lines on it. It seems like I'm not able to overlay the lines I draw onto the ImageView. If I create a new class (myPainter) which extends 'View', hook myPainter.onDraw() and then setContentView(mp) in onCreate() from the activity, all I get are the drawn lines. My ImageView is gone from onCreate(). How do I get the ImageView and lines to show up in the same layout? I'm also Override'ing onTouch() for the ImageView so I can get the xy click locations from it.</p> <pre><code> public class myPainter extends View { public myPainter (Context context) { super (context); } @Override protected void onDraw(Canvas canvas) { super.onDraw (canvas); Paint p = new Paint(); p.setColor(Color.RED); canvas.drawLine (E_XMIN, E_YMIN, E_XMAX, E_YMAX, p); } } @Override public void onCreate (Bundle savedInstanceState) { super.onCreate (savedInstanceState); setContentView (R.layout.main); ImageView iv = (ImageView) findViewById(R.id.ImageView01); iv.setOnTouchListener (this); // this draws my lines, but I loose the pic above ^^^ myPainter mp = new myPainter(this); setContentView(mp); } </code></pre> <hr> <p><strong>UPDATE:</strong> </p> <p>I think I've literally painted myself into a corner. How would I add a frameAnimation to this code now in the onTouchEvent() method? Like where the user touches the screen. The Android rocketAnimation example causes an exception if I add code to the myPainter() class: </p> <pre><code> @Override public boolean onTouchEvent (MotionEvent event) { //Log.d (TAG, "touchevent in myPainter"); switch (event.getAction()) { case MotionEvent.ACTION_DOWN: Log.d (TAG, "down x:" + event.getX() + " y:" + event.getY()); int wClick = getClick (event.getX(), event.getY()); AnimationDrawable touchAni; ImageView iv = (ImageView) findViewById (R.drawable.triangle); iv.setBackgroundResource (R.drawable.nova); touchAni = (AnimationDrawable) iv.getBackground (); touchAni.start (); return true; } return super.onTouchEvent (event); } </code></pre>
 

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