Android drawable 反射取资源id

通过反射来获取资源id

try{
    String resName = "ic_launcher";
    int resId = R.drawable.class.getDeclaredField(resName).getInt(R.drawable.class);
    imageView.setImageResource(resId);
} catch (IllegalArgumentException e) {
    e.printStackTrace();
} catch (IllegalAccessException e) {
    e.printStackTrace();
} catch (NoSuchFieldException e) {
    e.printStackTrace();
}