Bitmap、Drawable之间的相互转化

[android]代码库

将Bitmap转化为byte数组：
ByteArrayOutputStream out = new ByteArrayOutputStream();
bitmap.compress(Bitmap.CompressFormat.PNG, 100, out);
byte[] array= out.toByteArray();

将byte数组转化为Bitmap
final ContentResolver contentResolver = context.getContentResolver();
final PackageManager manager = context.getPackageManager();
final Cursor c = contentResolver.query(uri, null, null, null, null);
final int icon3DIndex = c.getColumnIndexOrThrow(ColumnName);
byte[] data = c.getBlob(icon3DIndex);
Bitmap bitmap = BitmapFactory.decodeByteArray(data, 0, data.length);

将Bitmap转化为Drawable：
Bitmap bitmap = new Bitmap(...); 
Drawable drawable = new BitmapDrawable(bitmap);
//Drawable drawable = new FastBitmapDrawable(bitmap);

将Drawable转化为Bitmap：
Canvas canvas = new Canvas(bitmap)
drawable.draw(canvas);
Drawable d = ImagesList.get(0); Bitmap bitmap =  ((BitmapDrawable)d).getBitmap();