From 261b7634df2abb55233d9470856bacedfe632801 Mon Sep 17 00:00:00 2001
From: danesfeder <dan.nesfeder@mapbox.com>
Date: Tue, 4 Sep 2018 09:03:39 -0400
Subject: [PATCH] Do not add Fragments to backstack in
 FragmentNavigationActivity

---
 .../fragment/FragmentNavigationActivity.java  | 32 ++++++++++++++-----
 1 file changed, 24 insertions(+), 8 deletions(-)

diff --git a/app/src/main/java/com/mapbox/services/android/navigation/testapp/activity/navigationui/fragment/FragmentNavigationActivity.java b/app/src/main/java/com/mapbox/services/android/navigation/testapp/activity/navigationui/fragment/FragmentNavigationActivity.java
index 67b6350dffc..867f4e9fa7b 100644
--- a/app/src/main/java/com/mapbox/services/android/navigation/testapp/activity/navigationui/fragment/FragmentNavigationActivity.java
+++ b/app/src/main/java/com/mapbox/services/android/navigation/testapp/activity/navigationui/fragment/FragmentNavigationActivity.java
@@ -7,6 +7,7 @@
 import android.support.v4.app.FragmentManager;
 import android.support.v4.app.FragmentTransaction;
 import android.support.v7.app.AppCompatActivity;
+import android.view.View;
 
 import com.mapbox.services.android.navigation.testapp.R;
 
@@ -16,6 +17,8 @@
 
 public class FragmentNavigationActivity extends AppCompatActivity {
 
+  private static final String FAB_VISIBLE_KEY = "restart_fab_visible";
+
   @BindView(R.id.restart_navigation_fab)
   FloatingActionButton restartNavigationFab;
 
@@ -27,9 +30,23 @@ protected void onCreate(@Nullable Bundle savedInstanceState) {
     initializeNavigationViewFragment(savedInstanceState);
   }
 
+  @Override
+  protected void onSaveInstanceState(Bundle outState) {
+    super.onSaveInstanceState(outState);
+    outState.putBoolean(FAB_VISIBLE_KEY, restartNavigationFab.getVisibility() == View.VISIBLE);
+  }
+
+  @Override
+  protected void onRestoreInstanceState(Bundle savedInstanceState) {
+    super.onRestoreInstanceState(savedInstanceState);
+    boolean isVisible = savedInstanceState.getBoolean(FAB_VISIBLE_KEY);
+    int visibility = isVisible ? View.VISIBLE : View.INVISIBLE;
+    restartNavigationFab.setVisibility(visibility);
+  }
+
   @OnClick(R.id.restart_navigation_fab)
   public void onClick(FloatingActionButton restartNavigationFab) {
-    replaceFragment(new NavigationFragment(), true);
+    replaceFragment(new NavigationFragment());
     restartNavigationFab.hide();
   }
 
@@ -38,28 +55,27 @@ public void showNavigationFab() {
   }
 
   public void showPlaceholderFragment() {
-    replaceFragment(new PlaceholderFragment(), false);
+    replaceFragment(new PlaceholderFragment());
   }
 
   private void initializeNavigationViewFragment(@Nullable Bundle savedInstanceState) {
     FragmentManager fragmentManager = getSupportFragmentManager();
     if (savedInstanceState == null) {
-      FragmentTransaction ft = fragmentManager.beginTransaction();
-      ft.add(R.id.navigation_fragment_frame, new NavigationFragment()).commit();
+      FragmentTransaction transaction = fragmentManager.beginTransaction();
+      transaction.disallowAddToBackStack();
+      transaction.add(R.id.navigation_fragment_frame, new NavigationFragment()).commit();
     }
   }
 
-  private void replaceFragment(Fragment newFragment, boolean addToBackStack) {
+  private void replaceFragment(Fragment newFragment) {
     String tag = String.valueOf(newFragment.getId());
     FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();
+    transaction.disallowAddToBackStack();
     transaction.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_OPEN);
     int fadeInAnimId = android.support.v7.appcompat.R.anim.abc_fade_in;
     int fadeOutAnimId = android.support.v7.appcompat.R.anim.abc_fade_out;
     transaction.setCustomAnimations(fadeInAnimId, fadeOutAnimId, fadeInAnimId, fadeOutAnimId);
     transaction.replace(R.id.navigation_fragment_frame, newFragment, tag);
-    if (addToBackStack) {
-      transaction.addToBackStack(tag);
-    }
     transaction.commit();
   }
 }