Fixed crash in UiListener when launching activity with screen off.

When launching MainActivity with the screen off (e.g. from Android Studio) the application would crash due to:

java.lang.IllegalStateException: Can not perform this action after onSaveInstanceState

Also use FragmentPagerAdapter in MainPagerAdapter as the number of tabs is small and can be stored in memory.

Test: manual
PiperOrigin-RevId: 179734952
Change-Id: Ib2ca9674f3174493da55bbbf0ef4053fcf73ab47

1 files changed, 7 insertions, 1 deletions

diff --git a/java/com/android/dialer/common/concurrent/UiListener.java b/java/com/android/dialer/common/concurrent/UiListener.java
index 9541dbc0c..df791301f 100644
--- a/java/com/android/dialer/common/concurrent/UiListener.java
+++ b/java/com/android/dialer/common/concurrent/UiListener.java
@@ -71,7 +71,10 @@ public class UiListener<OutputT> extends Fragment {
     if (uiListener == null) {
       LogUtil.i("UiListener.create", "creating new UiListener for " + taskId);
       uiListener = new UiListener<>();
-      fragmentManager.beginTransaction().add(uiListener, taskId).commit();
+      // When launching an activity with the screen off, its onSaveInstanceState() is called before
+      // its fragments are created, which means we can't use commit() and need to use
+      // commitAllowingStateLoss(). This is not a problem for UiListener which saves no state.
+      fragmentManager.beginTransaction().add(uiListener, taskId).commitAllowingStateLoss();
     }
     return uiListener;
   }
@@ -130,6 +133,9 @@ public class UiListener<OutputT> extends Fragment {
   public void onCreate(Bundle savedInstanceState) {
     super.onCreate(savedInstanceState);
     setRetainInstance(true);
+    // Note: We use commitAllowingStateLoss when attaching the fragment so it may not be safe to
+    // read savedInstanceState in all situations. (But it's not anticipated that this fragment
+    // should need to rely on saved state.)
   }
 
   @Override