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copied!<blockquote> <p>Do not create new canvas for each color, rather create new paths.</p> </blockquote> <p>Create <code>Path</code>'s for every new time the user touches the canvas and theoretically draws something. Store that new path along with its color and in the <code>onDraw</code> method iterate over the path structure and draw each of the paths with its saved color:</p> <pre><code>// this will hold the data of each path the user draws class DrawnItem { int color = Color.GREEN; // default values Path line = new Path(); } Paint paint; int mCurrentColor = Color.GREEN; // start with green ArrayList<DrawnItem> mDrawings = new ArrayList<DrawnItem>(); // in the onDraw method: protected void onDraw(Canvas canvas) { final int count = mDrawings.size(); for (int i = 0; i < count; i++) { final DrawnItem item = mDrawings.get(i); paint.setColor(item.color); canvas.drawPath(item.line, paint); } paint.setColor(mCurrentColor); canvas.drawCircle(x, y, 10, paint); } private DrawnItem mCurrentItem = null; // and in the onTouch method: public boolean onTouchEvent(MotionEvent event) { final int action = event.getAction(); switch (action) { case MotionEvent.ACTION_DOWN: // the user started a new drawing so build a new DrawnItem mCurrentItem = new DrawnItem(); mCurrentitem.color= mCurrentColor; mDrawings.add(mCurrentItem); // use the item.line to setup the Path with the x and y values // .... invalidate(); break; case MotionEvent.ACTION_MOVE: x = event.getX(); y = event.getY(); mCurrentItem.line.lineTo(x, y); invalidate(); break; case MotionEvent.ACTION_UP: mCurrentItem.line.lineTo(event.getX(), event.getY()); mCurrentItem = null; invalidate(); break; case MotionEvent.ACTION_CANCEL: mCurrentItem = null; // this drawing session was canceled so this DrawnItem is now closed break; default: break; </code></pre> <p>Now, in your dialog, the only thing you need to do is to update the <code>mCurrentColor</code> of the custom view to point of the chosen color and from that point on the path will be drawn with the dedicated color. If the user switches the color to a previous stored color then the path corresponding for that color will be selected.</p> <p>Code for saving the view as a <code>Bitmap</code> in the doInBackground():</p> <pre><code>Bitmap bitmap = Bitmap.createBitmap(layout.getWidth(), layout.getHeight(), Bitmap.Config. RGB_565); Canvas canvas = new Canvas(bitmap); layout.draw(canvas); </code></pre> <blockquote> <p>Clear the entire canvas if ERASE button is pressed</p> </blockquote> <p>Clear the previous path structure and call <code>invalidate()</code> on your custom view:</p> <pre><code>mDrawings.clear(); customView.invalidate(); </code></pre>

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