android传递图片和图片与byte转换

activity 之间直接传递图片时
  Intent intent = new Intent(this, NewActivity.class);
  intent.putExtra("BitmapImage", bitmap);
  Bitmap bitmap = (Bitmap) intent.getParcelableExtra("BitmapImage");

去掉seekBarBackground
  创建一个blank drawable 然后satBar.setProgressDrawable(invisibleBackground);
  也许这样也可以setBackgroundDrawable(null)


1、Drawable → Bitmap
public static Bitmap drawableToBitmap(Drawable drawable) {  
          
        Bitmap bitmap = Bitmap  
                        .createBitmap(  
                                        drawable.getIntrinsicWidth(),  
                                        drawable.getIntrinsicHeight(),  
                                        drawable.getOpacity() != PixelFormat.OPAQUE ? Bitmap.Config.ARGB_8888  
                                                        : Bitmap.Config.RGB_565);  
        Canvas canvas = new Canvas(bitmap);  
        //canvas.setBitmap(bitmap);  
        drawable.setBounds(0, 0, drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight());  
        drawable.draw(canvas);  
        return bitmap;  
} 

public static Bitmap drawableToBitmap(Drawable drawable) {
       
        Bitmap bitmap = Bitmap
                        .createBitmap(
                                        drawable.getIntrinsicWidth(),
                                        drawable.getIntrinsicHeight(),
                                        drawable.getOpacity() != PixelFormat.OPAQUE ? Bitmap.Config.ARGB_8888
                                                        : Bitmap.Config.RGB_565);
        Canvas canvas = new Canvas(bitmap);
        //canvas.setBitmap(bitmap);
        drawable.setBounds(0, 0, drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight());
        drawable.draw(canvas);
        return bitmap;
}

2、从资源中获取Bitmap



Java代码 
Resources res=getResources();  
 
Bitmap bmp=BitmapFactory.decodeResource(res, R.drawable.pic); 

Resources res=getResources();

Bitmap bmp=BitmapFactory.decodeResource(res, R.drawable.pic);

3、Bitmap → byte[]



Java代码 
private byte[] Bitmap2Bytes(Bitmap bm){  
    ByteArrayOutputStream baos = new ByteArrayOutputStream();    
    bm.compress(Bitmap.CompressFormat.PNG, 100, baos);    
    return baos.toByteArray();  
   } 

private byte[] Bitmap2Bytes(Bitmap bm){
    ByteArrayOutputStream baos = new ByteArrayOutputStream(); 
    bm.compress(Bitmap.CompressFormat.PNG, 100, baos); 
    return baos.toByteArray();
   }
4、 byte[] → Bitmap

Java代码 
private Bitmap Bytes2Bimap(byte[] b){  
            if(b.length!=0){  
                return BitmapFactory.decodeByteArray(b, 0, b.length);  
            }  
            else {  
                return null;  
            }  
      }