TrickyDialogFragment.java

package com.electricobjects.client.onboarding;

import android.app.Dialog;
import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.v4.content.ContextCompat;
import android.view.Gravity;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.view.ViewTreeObserver;
import android.view.Window;
import android.view.WindowManager;
import android.widget.FrameLayout;
import android.widget.TextView;

public class OnboardingMessageDialog extends CustomDimDialogFragment implements View.OnClickListener {

    private View calloutView;

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        super.onCreateView(inflater, container, savedInstanceState);

        View view = inflater.inflate(R.layout.dialog_onboarding, container, false);
        
        int message = R.string.message;
        ((TextView) view.findViewById(R.id.onboarding_message)).setText(message);
        view.findViewById(R.id.onboarding_ok_button).setOnClickListener(this);

        // code to add callout button
        ViewTreeObserver vto = getActivity().findViewById(R.id.button_add_to_playlist).getViewTreeObserver();
        vto.addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener() {
            @Override
            public void onGlobalLayout() {
                FloatingActionButton addFab = (FloatingActionButton) calloutView.findViewById(R.id.button_add_to_playlist);
                FrameLayout.LayoutParams params = (FrameLayout.LayoutParams) addFab.getLayoutParams();
                
                // find the view to call out in the parent activity
                View originalView = getActivity().findViewById(R.id.button_add_to_playlist);

                params.topMargin = originalView.getTop();
                params.leftMargin = originalView.getLeft();
                addFab.setLayoutParams(params);

                ViewTreeObserver obs = getActivity().findViewById(R.id.button_add_to_playlist).getViewTreeObserver();
                obs.removeOnGlobalLayoutListener(this);
            }
        });
        calloutView = inflater.inflate(R.layout.layout_callout_add_playlist_button, container, false);
        calloutView.setLayoutParams(new FrameLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT));
        
        // add as a content view on the Activity
        getActivity().getWindow().addContentView(calloutView, new FrameLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT));

        return view;
    }

    @Override
    public Dialog onCreateDialog(Bundle savedInstanceState) {
        Dialog dialog = super.onCreateDialog(savedInstanceState);
        dialog.requestWindowFeature(Window.FEATURE_NO_TITLE);

        // set the dialog to float to the top 1/3rd of the screen (roughly)
        WindowManager.LayoutParams params = dialog.getWindow().getAttributes();
        params.gravity = Gravity.TOP;
        params.verticalMargin = 0.2f;
        dialog.getWindow().setAttributes(params);

        dialog.getWindow().setLayout(WindowManager.LayoutParams.MATCH_PARENT, WindowManager.LayoutParams.MATCH_PARENT);

        return dialog;
    }

    @Override
    public void onClick(View v) {
        switch (v.getId()) {
            case R.id.onboarding_ok_button:
                dismissAllowingStateLoss();
                break;
            default:
                dismissAllowingStateLoss();
        }
    }

    @Override
    public void onDestroyView() {
        super.onDestroyView();
        
        // remember to remove the callout view on destroy view!
        if (calloutView != null) {
            ViewGroup parent = (ViewGroup) calloutView.getParent();
            if (parent != null) {
                parent.removeView(calloutView);
            }
            calloutView = null;
        }
    }
}