资源图片和BItmap、Drawable互转

//Bitmap 转 Drawable
BitmapDrawable bd = new BitmapDrawable(bitmap);

//Drawable 转 Bitmap
Drawable db = XX;
BitmapDrawable bd = new (BitmapDrawable)db;
Bitmap bmp = bd.getBitmap();

//资源图片 转 Drawable
Resources r = getBaseContext().getResources();
Drawable d = r.getDrawable(R.drawable.XX);

//紫红色
et.setTextColor(Color.MAGENTA);

//直接拿系统资源色做背景
btn.setBackgroundDrawableResource(R.color.red_bg);