Update FocusFinder

Don't return the current view when finding the next or previous view.

Bug: 158492287
Test: atest cts/tests/tests/view/src/android/view/cts/FocusFinderTest.java
atest frameworks/base/core/tests/coretests/src/android/view/FocusFinderTest.java

Change-Id: Ib5c1854d1a13b9469ca55dfbf0be61bead47e29e
(cherry picked from commit 713af5fdd39a2b56efe89d1125d6864f92c6298f)

1 files changed, 11 insertions, 8 deletions

diff --git a/core/java/android/view/FocusFinder.java b/core/java/android/view/FocusFinder.java
index 713cfb48c95f..064bc6947fc4 100644
--- a/core/java/android/view/FocusFinder.java
+++ b/core/java/android/view/FocusFinder.java
@@ -311,6 +311,9 @@ public class FocusFinder {
         }
 
         final int count = focusables.size();
+        if (count < 2) {
+            return null;
+        }
         switch (direction) {
             case View.FOCUS_FORWARD:
                 return getNextFocusable(focused, focusables, count);
@@ -373,29 +376,29 @@ public class FocusFinder {
     }
 
     private static View getNextFocusable(View focused, ArrayList<View> focusables, int count) {
+        if (count < 2) {
+            return null;
+        }
         if (focused != null) {
             int position = focusables.lastIndexOf(focused);
             if (position >= 0 && position + 1 < count) {
                 return focusables.get(position + 1);
             }
         }
-        if (!focusables.isEmpty()) {
-            return focusables.get(0);
-        }
-        return null;
+        return focusables.get(0);
     }
 
     private static View getPreviousFocusable(View focused, ArrayList<View> focusables, int count) {
+        if (count < 2) {
+            return null;
+        }
         if (focused != null) {
             int position = focusables.indexOf(focused);
             if (position > 0) {
                 return focusables.get(position - 1);
             }
         }
-        if (!focusables.isEmpty()) {
-            return focusables.get(count - 1);
-        }
-        return null;
+        return focusables.get(count - 1);
     }
 
     private static View getNextKeyboardNavigationCluster(