Android中Bitmap, Drawable, Byte,ID之间的转化
1. Bitmap 转化为 byte
ByteArrayOutputStream out = new ByteArrayOutputStream();
bitmap.compress(Bitmap.CompressFormat.PNG, 100, out);
byte[] array= out.toByteArray();
2. byte转化为bitmap
Bitmap bitmap = BitmapFactory.decodeByteArray(data, 0, data.length);
3. bitmap转化为Drawable
Drawable drawable = new FastBitmapDrawable(bitmap);
4. Drawable转化为bitmap
a. BitmapDrawable, FastBitmapDrawable直接用getBitmap
b. 其他类型的Drawable用Canvas画到一个bitmap上
Canvas canvas = new Canvas(bitmap)
drawable.draw(canvas)
5.id转化graphic.drawable
Drawable drawable = activity.getResources().getDrawable(R.drawable.icon);
6.id转化成Bitmap
Bitmap bitmap = BitmapFactory. decodeResource (Resources res, int id)