How to check if the current activity has a dialog in front?

Question

I am using a third-party library and sometimes it pops up a dialog. Before I finish the current activity, I want to check whether there is a dialog popped up in the current con

Answer 1

This uses reflection and hidden APIs to get the currently active view roots. If an alert dialog shows this will return an additional view root. But careful as even a toast popup will return an additional view root.

I've confirmed compatibility from Android 4.1 to Android 6.0 but of course this may not work in earlier or later Android versions.

I've not checked the behavior for multi-window modes.

@SuppressWarnings("unchecked")
public static List<ViewParent> getViewRoots() {

    List<ViewParent> viewRoots = new ArrayList<>();

    try {
        Object windowManager;
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN_MR1) {
            windowManager = Class.forName("android.view.WindowManagerGlobal")
                    .getMethod("getInstance").invoke(null);
        } else {
            Field f = Class.forName("android.view.WindowManagerImpl")
                    .getDeclaredField("sWindowManager");
            f.setAccessible(true);
            windowManager = f.get(null);
        }

        Field rootsField = windowManager.getClass().getDeclaredField("mRoots");
        rootsField.setAccessible(true);

        Field stoppedField = Class.forName("android.view.ViewRootImpl")
                .getDeclaredField("mStopped");
        stoppedField.setAccessible(true);

        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN_MR1) {
            List<ViewParent> viewParents = (List<ViewParent>) rootsField.get(windowManager);
            // Filter out inactive view roots
            for (ViewParent viewParent : viewParents) {
                boolean stopped = (boolean) stoppedField.get(viewParent);
                if (!stopped) {
                    viewRoots.add(viewParent);
                }
            }
        } else {
            ViewParent[] viewParents = (ViewParent[]) rootsField.get(windowManager);
            // Filter out inactive view roots
            for (ViewParent viewParent : viewParents) {
                boolean stopped = (boolean) stoppedField.get(viewParent);
                if (!stopped) {
                    viewRoots.add(viewParent);
                }
            }
        }
    } catch (Exception e) {
        e.printStackTrace();
    }

    return viewRoots;
}

Answer 2

For anyone reading this and wondering how to detect a Dialog above fragment or activity, my problem was that inside my base fragment I wanted to detect if I'm displaying a Dialog on top of my fragment. The dialog itself was displayed from my activity and I didn't want to reach it there, so the solution I came up with (Thanks to all answers related to this kind of question) was to get the view (or you can get the view.rootView) of my fragment and check whether any of its children have the focus or not. If none of its children have no focus it means that there is something (hopefully a Dialog) being displayed above my fragment.

// Code inside my base fragment:
val dialogIsDisplayed = (view as ViewGroup).children.any { it.hasWindowFocus() }