Conversion between Android-drawable, bitmap, and byte []

Android will perform some type conversion when processing a write image resource. Now I have time to sort it out:
 
1. drawable → bitmap
Java code

1. Public static bitmap drawabletobitmap (drawable ){
3. Bitmap bitmap = bitmap
4. . Createbitmap (
5. Drawable. getintrinsicwidth (),
6. Drawable. getintrinsicheight (),
7. Drawable. getopacity ()! = Pixelformat. opaque? Bitmap. config. argb_8888
8. : Bitmap. config. rgb_565 );
9. Canvas canvas = new canvas (Bitmap );
10. // Canvas. setbitmap (Bitmap );
11. Drawable. setbounds (0, 0, drawable. getintrinsicwidth (), drawable. getintrinsicheight ());
12. Drawable. Draw (canvas );
13. Return bitmap;
14. }

 
2. Obtain bitmap from a resource
 
Java code

1. Resources res = getresources ();
3. Bitmap BMP = bitmapfactory. decoderesource (Res, R. drawable. PIC );

 
3. Bitmap → byte []
 
Java code

1. Private byte [] bitmap2bytes (Bitmap BM ){
2. Bytearrayoutputstream baos = new bytearrayoutputstream ();
3. BM. Compress (bitmap. compressformat. PNG, 100, baos );
4. Return baos. tobytearray ();
5. }

 
4. byte [] → bitmap
Java code

1. Private bitmap bytes2bimap (byte [] B ){
2. If (B. length! = 0 ){
3. Return bitmapfactory. decodebytearray (B, 0, B. Length );
4. }
5. Else {
6. Return NULL;
7. }
8. }

 
 
 
The above are some of the transformations I have encountered in practice. In the future, we don't need to look around for similar conversions. I hope they will be of some use to everyone!