Android DataBinding Activity finish()

Question

I am trying to implement MVVM in my app with DataBinding library. For simple tasks that I have accomplish I can find the way out, but problem is that I cannot finish activity after some action.

Problem:

After receiving specific broadcast I have to close activity from ViewModel class. Since VM class doesn't have reference of the View, how can I finish the activity? To be precise, I have splash screen and corresponding VM class for it that starts IntentService for downloading a data. After the data has been downloaded I have to finish the splash screen and start MainActivity. I have found the way to start new Activity from VM, but to finish the previous one is the mystery.

Can you please help me? Thanks!

Answer 1

Create a SplashStatus model with a ObservableBoolean:

private static class SplashStatus {
   public final ObservableBoolean isFinished = new ObservableBooelan();
}

Here is your Splash layout:

<layout xmlns:android="http://schemas.android.com/apk/res/android">
   <data>
       <variable name="status" type="com.example.SplashStatus"/>
   </data>
   <LinearLayout
       android:orientation="vertical"
       android:layout_width="match_parent"
       android:layout_height="match_parent">
       <TextView android:layout_width="wrap_content"
           android:layout_height="wrap_content"
           android:text="Splash Screen"
           android:onFinish="@{status.isFinished}"/>
   </LinearLayout>
</layout>

And binding adapter method:

@BindingAdapter("android:onFinish")
public static void finishSplash(View view, boolean isFinished) {

   if(isFinished){
       ((Activity)(view.getContext())).startActivity(new Intent(view.getContext(), MainActivity.class))
       ((Activity)(view.getContext())).finish();
   }
}

In the SplashActivity.java init your data binding on onCreate. Whenever you assign isFinished.set(true) onFinished method will start your MainActivity and finish current.

Answer 2

if you want just to finish() the activity from layout with databinding:

android:onClick="@{(view)->((Activity)(view.getContext())).finish()}"