Fix crash and icon change issue with shared element transition.

app/src/main/java/org/thoughtcrime/securesms/main/MainActivityListHostFragment.kt

@@ -14,6 +14,7 @@ import androidx.fragment.app.Fragment
 import androidx.fragment.app.viewModels
 import androidx.navigation.NavController
 import androidx.navigation.NavDestination
+import androidx.navigation.Navigator
 import androidx.navigation.findNavController
 import androidx.navigation.fragment.FragmentNavigatorExtras
 import org.signal.core.util.concurrent.SimpleTask
@@ -106,14 +107,23 @@ class MainActivityListHostFragment : Fragment(R.layout.main_activity_list_host_f
     if (state.tab == ConversationListTab.CHATS) {
       return
     } else {
+      val cameraFab = requireView().findViewById<View>(R.id.camera_fab_new)
+      val newConvoFab = requireView().findViewById<View>(R.id.fab_new)
+
+      val extras: Navigator.Extras? = if (cameraFab == null || newConvoFab == null) {
+        null
+      } else {
+        FragmentNavigatorExtras(
+          cameraFab to "camera_fab",
+          newConvoFab to "new_convo_fab"
+        )
+      }
+
       navController.navigate(
         R.id.action_conversationListFragment_to_storiesLandingFragment,
         null,
         null,
-        FragmentNavigatorExtras(
-          requireView().findViewById<View>(R.id.camera_fab_new) to "camera_fab",
-          requireView().findViewById<View>(R.id.fab_new) to "new_convo_fab"
-        )
+        extras
       )
     }
   }

app/src/main/java/org/thoughtcrime/securesms/stories/landing/StoriesLandingFragment.kt

@@ -97,6 +97,7 @@ class StoriesLandingFragment : DSLSettingsFragment(layoutId = R.layout.stories_l
     setEnterSharedElementCallback(object : SharedElementCallback() {
       override fun onSharedElementStart(sharedElementNames: MutableList<String>?, sharedElements: MutableList<View>?, sharedElementSnapshots: MutableList<View>?) {
         if (sharedElementNames?.contains("camera_fab") == true) {
+          cameraFab.setImageResource(R.drawable.ic_compose_24)
           lifecycleDisposable += Single.timer(200, TimeUnit.MILLISECONDS).subscribeBy {
             cameraFab.setImageResource(R.drawable.ic_camera_outline_24)
           }

app/src/main/res/layout/stories_landing_fragment.xml

@@ -55,7 +55,7 @@
         app:backgroundTint="@color/signal_colorPrimaryContainer"
         app:layout_constraintBottom_toBottomOf="parent"
         app:layout_constraintEnd_toEndOf="parent"
-        app:srcCompat="@drawable/ic_compose_outline_24"
+        app:srcCompat="@drawable/ic_camera_outline_24"
         app:tint="@color/signal_colorOnPrimaryContainer" />
 
     <TextView

app/src/main/res/transition/change_transform_fabs.xml

@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="utf-8"?>
-<transitionSet android:duration="200"
+<transitionSet android:duration="100"
     android:interpolator="@anim/camera_fab_cubic_easing_interpolator"
     xmlns:android="http://schemas.android.com/apk/res/android">
     <transition class="org.thoughtcrime.securesms.animation.transitions.FabElevationFadeTransform" />