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POAndroid : Not able to do canvas painting on image uploaded from sd card
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copied!<p>I am trying to build a paint application. The application is divided into 3 parts:</p> <ol> <li>Initially the application is having a white background and user can paint on the canvas using different brush sizes and different colors</li> <li>User can save the canvas image to sd card</li> <li>User can upload the image from sd card and again paint on the image</li> </ol> <p>Point 1 and 2 are working fine and I am able to paint on a white background. But point 3, when I upload any image from Gallery and try to paint on the image, then the previous path painted is getting disappeared and only new path is displayed.</p> <p>code :</p> <pre><code>onDraw(Canvas canvas){ mBitmap = Bitmap.createBitmap(320, 480, Bitmap.Config.ARGB_8888); mCanvas = new Canvas(mBitmap); mPath = new Path(); mBitmapPaint = new Paint(Paint.DITHER_FLAG); canvas.drawColor(Color.WHITE); canvas.drawBitmap(mBitmap, 0, 0, mBitmapPaint); canvas.drawPath(mPath, mPaint); } onTouch - > case MotionEvent.ACTION_DOWN: mPath.reset(); mPath.moveTo(x, y); mX = x; mY = y; invalidate(); break; case MotionEvent.ACTION_MOVE: 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; } invalidate(); break; case MotionEvent.ACTION_UP: mPath.lineTo(mX, mY); mCanvas.drawPath(mPath, mPaint); mPath.reset(); break; mBitmap = BitmapFactory.decodeFile(filePath); -----this is from sd card </code></pre>

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