In App Screenshots

One of the new highly touted features in Ice Cream Sandwich is screenshot support. This allows a user to take a snapshot of their screen and send it to anyone. Obviously this is a valuable debugging tool as users can send how an app looked when it did something weird.

It is possible to partially support screenshots within your own app. This is essentially done by getting the content root view of your Activity and rendering it against a Canvas.

The code below does just that. (Source excerpt from the android-beryl library.)

public class Screenshot {
  private final View view;
  /** Create snapshots based on the view and its children. */
  public Screenshot(View root) {
    this.view = root;
  }
  /** Create snapshot handler that captures the root of the whole activity. */
  public Screenshot(Activity activity) {
    final View contentView = activity.findViewById(android.R.id.content);
    this.view = contentView.getRootView();
  }
  /** Take a snapshot of the view. */
  public Bitmap snap() {
    Bitmap bitmap = Bitmap.createBitmap(this.view.getWidth(), this.view.getHeight(), Config.ARGB_8888);
    Canvas canvas = new Canvas(bitmap);
    view.draw(canvas);
    return bitmap;
  }
}