Second fragment send messages -> First fragment receive messages.

Author: remixgrjp

app/src/main/java/asia/remix/myfragment/FirstFragment.java

@@ -6,13 +6,15 @@
 import android.view.View;
 import android.view.ViewGroup;
 import android.widget.Button;
+import android.widget.TextView;
 
 import androidx.annotation.NonNull;
 import androidx.fragment.app.Fragment;
 import androidx.navigation.fragment.NavHostFragment;
 
 public class FirstFragment extends Fragment{
 	static final String TAG= "FirstFragment";
+	static final String KEY= "FirstFragment";//for recevie key
 
 	@Override
 	public void onCreate( Bundle savedInstanceState ){
@@ -39,6 +41,11 @@ public void onClick( View view ){
 				NavHostFragment.findNavController( FirstFragment.this ).navigate( R.id.action_FirstFragment_to_SecondFragment, bundle );
 			}
 		} );
+
+		TextView textView = view.findViewById( R.id.textview_first );
+		Bundle b= ( null == getArguments() ? new Bundle() : getArguments() );
+		String s= requireActivity().getString( R.string.hello_first_fragment );
+		textView.setText( String.format( s, b.getString( KEY, "-" ) ) );
 	}
 
 	@Override

app/src/main/java/asia/remix/myfragment/SecondFragment.java

@@ -37,7 +37,9 @@ public void onViewCreated( @NonNull View view, Bundle savedInstanceState ){
 		button.setOnClickListener( new View.OnClickListener(){
 			@Override
 			public void onClick( View view ){
-				NavHostFragment.findNavController( SecondFragment.this ).navigate( R.id.action_SecondFragment_to_FirstFragment );
+				Bundle bundle= new Bundle();
+				bundle.putString( FirstFragment.KEY , "From 2" );
+				NavHostFragment.findNavController( SecondFragment.this ).navigate( R.id.action_SecondFragment_to_FirstFragment, bundle );
 			}
 		} );
 

app/src/main/res/values/strings.xml

@@ -7,6 +7,6 @@
 	<string name="next">Next</string>
 	<string name="previous">Previous</string>
 
-	<string name="hello_first_fragment">Hello first fragment</string>
+	<string name="hello_first_fragment">Hello first fragment. Arg: %1$s</string>
 	<string name="hello_second_fragment">Hello second fragment. Arg: %1$s</string>
 </resources>