Stack Overflow archive
5 score

Android Toolbar overflow menu view id

score
5
question views
2.7K
license
CC BY-SA 3.0

The overflow menu item doesn't have a resource id. I found the overflow view by traversing the toolbar. The debugger showed an id of -1 and the Hierarchy Viewer showed no resource-id.

Here is how I found the overflow view without a resource id:

java
/**
 * Get the OverflowMenuButton.
 *
 * @param activity
 *     the Activity
 * @return the OverflowMenuButton or {@code null} if it doesn't exist.
 */
public static ImageView getOverflowMenuButton(Activity activity) {
  return findOverflowMenuButton(activity, findActionBar(activity));
}

static ImageView findOverflowMenuButton(Activity activity, ViewGroup viewGroup) {
  if (viewGroup == null) {
    return null;
  }
  ImageView overflow = null;
  for (int i = 0, count = viewGroup.getChildCount(); i < count; i++) {
    View v = viewGroup.getChildAt(i);
    if (v instanceof ImageView && (v.getClass().getSimpleName().equals("OverflowMenuButton") ||
        v instanceof ActionMenuView.ActionMenuChildView)) {
      overflow = (ImageView) v;
    } else if (v instanceof ViewGroup) {
      overflow = findOverflowMenuButton(activity, (ViewGroup) v);
    }
    if (overflow != null) {
      break;
    }
  }
  return overflow;
}

static ViewGroup findActionBar(Activity activity) {
  try {
    int id = activity.getResources().getIdentifier("action_bar", "id", "android");
    ViewGroup actionBar = null;
    if (id != 0) {
      actionBar = (ViewGroup) activity.findViewById(id);
    }
    if (actionBar == null) {
      return findToolbar((ViewGroup) activity.findViewById(android.R.id.content).getRootView());
    }
  } catch (Exception e) {
    e.printStackTrace();
  }
  return null;
}

static ViewGroup findToolbar(ViewGroup viewGroup) {
  ViewGroup toolbar = null;
  for (int i = 0, len = viewGroup.getChildCount(); i < len; i++) {
    View view = viewGroup.getChildAt(i);
    if (view.getClass() == android.support.v7.widget.Toolbar.class ||
        view.getClass().getName().equals("android.widget.Toolbar")) {
      toolbar = (ViewGroup) view;
    } else if (view instanceof ViewGroup) {
      toolbar = findToolbar((ViewGroup) view);
    }
    if (toolbar != null) {
      break;
    }
  }
  return toolbar;
}

Calling getOverflowMenuButton(activity) will return null in onCreate because the overflow menu isn't laid out yet. To get the overflow menu in onCreate I did the following:

java
findViewById(android.R.id.content).post(new Runnable() {
  @Override public void run() {
    ImageView overflow = getOverflowMenuButton(MainActivity.this);
  }
});

Originally posted on Stack Overflow. Public user contributions are licensed under Creative Commons Attribution-ShareAlike.