In ondraw I am getting out of memory exception in android

Question

hi am doing one applicattion here i need to implement drawing function.so i taken myview as custom class and inside on draw i did more allocations.so i am getting memory exception.so where i need to allocation can u any one having idea about this please sugeest me..

MyView .class

    public class MyView extends View
    {

            private Canvas  mCanvas;
            private Path    mPath;
            private Paint   mBitmapPaint;

        public MyView(Context context) {
            super(context);
            // TODO Auto-generated constructor stub
             mPath = new Path();
                mBitmapPaint = new Paint(Paint.DITHER_FLAG);
        }
         @Override
            protected void onSizeChanged(int w, int h, int oldw, int oldh)     {
                super.onSizeChanged(w, h, oldw, oldh);
                if (mBitmap != null) {
                    mBitmap.recycle();
                    mBitmap=null;
                 }

                mBitmap = Bitmap.createBitmap(w, h, Bitmap.Config.ARGB_8888);
                mCanvas = new Canvas(mBitmap);
                mCanvas.setBitmap(mBitmap);


            }


          @Override
            protected void onDraw(Canvas canvas) {

              if(action)
              {
                  invalidate();
              }

              Paint painto = new Paint();
               painto.setAntiAlias(true);
              painto.setColor(getResources().getColor(R.color.magnata));


               painto.setStrokeWidth(3);
               painto.setStyle(Paint.Style.FILL);


              int leftx1=(int)(15*(screenWidth/1024));
                 int leftx2=(int)(1010*(screenWidth/1024));
                    int topy1=(int)(60*(screenHeight/600));
                    int topy2=(int)(530*(screenHeight/600));

                       canvas.drawLine(leftx1, topy1, leftx2, topy1, painto);   
                       canvas.drawLine(leftx1, topy1, leftx1, topy2, painto);
                       canvas.drawLine(15, topy2, leftx2, topy2, painto);
                       canvas.drawLine(leftx2, topy1, leftx2, topy2, painto);



            bitmapOrg = BitmapFactory.decodeResource(getResources(),
                        R.drawable.circles1_4);
            int leftorg=(int)(150*(screenWidth/1024));
            int toporg=(int)(110*(screenHeight/600));
              canvas.drawBitmap(bitmapOrg, leftorg, toporg, painto);

              bitmapOrg1 = BitmapFactory.decodeResource(getResources(),
                        R.drawable.circles1_5);
              int leftorg1=(int)(430*(screenWidth/1024));
                int toporg1=(int)(130*(screenHeight/600));
               canvas.drawBitmap(bitmapOrg1, leftorg1,toporg1, painto);

       bitmapOrg2 = BitmapFactory.decodeResource(getResources(),
                        R.drawable.circles1_6);
       int leftorg2=(int)(650*(screenWidth/1024));
               canvas.drawBitmap(bitmapOrg2, leftorg2,toporg, painto);

         bitmapOrg3 = BitmapFactory.decodeResource(getResources(),
                        R.drawable.circles1_1);
         int leftorg3=(int)(170*(screenWidth/1024));
         int toporg3=(int)(350*(screenHeight/600));
               canvas.drawBitmap(bitmapOrg3, leftorg3,toporg3, painto);

              bitmapOrg4 = BitmapFactory.decodeResource(getResources(),
                        R.drawable.circles1_3);
              int leftorg4=(int)(680*(screenWidth/1024));
               canvas.drawBitmap(bitmapOrg4, leftorg4,toporg3, painto);

            bitmapOrg5 = BitmapFactory.decodeResource(getResources(),
                        R.drawable.circles1_2);
            int leftorg5=(int)(400*(screenWidth/1024));
             int toporg5=(int)(300*(screenHeight/600));
               canvas.drawBitmap(bitmapOrg5, leftorg5,toporg5, painto);


               Paint paint1 = new Paint();
                paint1.setAntiAlias(true);
                paint1.setColor(Color.BLACK);
                paint1.setStrokeWidth(3);
                paint1.setStyle(Paint.Style.FILL);
                paint1.setTextSize(13);
                canvas.drawText("Get  ready  to  write  place  your  pen  on  the  dot  and  follow  direction ", 120, 20, paint1);
                canvas.drawText("indicated  by  the  arrow . ", 120, 38, paint1);


                Paint p = new Paint();
                p.setAntiAlias(true);
                p.setTextSize(120);
                p.setColor(Color.LTGRAY);
                             Typeface font = Typeface.createFromAsset(getAssets(), "font/KINDTRG.TTF"); 




               canvas.drawBitmap(mBitmap, 0, 0, mBitmapPaint);

                canvas.drawPath(mPath, mPaint); 


     }  
     private float mX, mY;
   private  final float TOUCH_TOLERANCE = 2;

     private void touch_start(float x, float y) {
       mPath.reset();
    mPath.moveTo(x, y);
  mX = x;
  mY = y;
 }
  private void touch_move(float x, float y) {
    float dx = Math.abs(x - mX);
      float dy = Math.abs(y - mY);
      if (dx >= TOUCH_TOLERANCE || dy >= TOUCH_TOLERANCE) {
  mPath.quadTo(mX, mY, (x + mX)/2, (y + mY)/2);
  mX = x;
  mY = y;
    }
   }
    private void touch_up() {
      mPath.lineTo(mX, mY);

     mCanvas.drawPath(mPath, mPaint);

    mPath.reset();
    }

         @Override
        public boolean onTouchEvent(MotionEvent event) {
           float x = event.getX();
           float y = event.getY();

       switch (event.getAction()) {
  case MotionEvent.ACTION_DOWN:
      touch_start(x, y);
      invalidate();
      break;
  case MotionEvent.ACTION_MOVE:
      touch_move(x, y);
      invalidate();
      break;
  case MotionEvent.ACTION_UP:
      touch_up();
      invalidate();
      break;
     }
       return true;
   }
      }

Answer 1

Try this way :: Release the imageview attached to that particular activity ..

protected void onDestroy() {
    super.onDestroy();

    unbindDrawables(findViewById(R.id.rl_main));
    System.gc();
}

private void unbindDrawables(View view) {
    if (view.getBackground() != null) {
        view.getBackground().setCallback(null);
    }
    if (view instanceof ViewGroup) {
        for (int i = 0; i < ((ViewGroup) view).getChildCount(); i++) {
            unbindDrawables(((ViewGroup) view).getChildAt(i));
        }
        ((ViewGroup) view).removeAllViews();
    }
}

Answer 2

Android gives you very little space to work with. Bitmaps are extremely heavy. You need to be careful how you use them. Make sure to recycle() them the instant you don't need them anymore, and consider not useing ARGB_8888 unless you have alpha channels that require transparency.