Android：根据随机变量更改imageView

Question

我正在尝试根据数组中的随机字符串将屏幕上的图像更改为其他内容。在这段代码中，我只是将字符串变量设置为“forest”，看看我是否可以让代码首先工作。

public class ImagevariabletestActivity extends Activity {
/** Called when the activity is first created. */

String source = "drawable/";
String image = "forest";

@Override

public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);

    String uri = source + image;

    // int imageResource = R.drawable.icon;
    int imageResource = getResources().getIdentifier(uri, null, getPackageName());

    ImageView imageView = (ImageView) findViewById(R.id.pic);
    Drawable image = getResources().getDrawable(imageResource);
    imageView.setImageDrawable(image);
}
}