在Android上实例化Canvas之后没有任何反应

Question

I don't know what is happening with Canvas :

// @param String source
Bitmap bmp = BitmapFactory.decodeFile(source);

Log.i("output", "This message will be printed!");

Canvas canvas = new Canvas(bmp);

Log.i("output", "This message will NOT be printed, canvas stop all!");

After instantiate Canvas , nothing is being printed and I cannot run any code, but the application does not close.

► Run (output after the call):

D/dalvikvm: GC_CONCURRENT freed 131K, 4% free 11360K/11783K, paused 11ms+1ms, total 15ms

D/OpenGLRenderer: TextureCache::callback: name, removed size, mSize = 22, 33856, 1157696

D/OpenGLRenderer: TextureCache::callback: name, removed size, mSize = 24, 36864, 1120832

Answer 1

You need to create another bitmap with the properties of bmp and pass that to the canvas:

Bitmap bmp = BitmapFactory.decodeFile(source);
Bitmap bmOverlay = Bitmap.createBitmap(bmp.getWidth(),bmp.getHeight(),bmp.getConfig());
Canvas canvas = new Canvas(bmOverlay);