From 7a8863ed3be1306daac62bb0a3139e2768a94007 Mon Sep 17 00:00:00 2001
From: Manuel Martin <manmartin@mozilla.com>
Date: Fri, 10 Jan 2020 20:54:44 +0100
Subject: [PATCH] Added check to avoid the nullpointerexception when focusing a
 window (#2477)

* Added check to avoid the nullpointerexception

* Check attached window null
---
 .../mozilla/vrbrowser/ui/widgets/Windows.java | 37 +++++++++++++------
 1 file changed, 26 insertions(+), 11 deletions(-)

diff --git a/app/src/common/shared/org/mozilla/vrbrowser/ui/widgets/Windows.java b/app/src/common/shared/org/mozilla/vrbrowser/ui/widgets/Windows.java
index 0df7d0f99..f070c30fb 100644
--- a/app/src/common/shared/org/mozilla/vrbrowser/ui/widgets/Windows.java
+++ b/app/src/common/shared/org/mozilla/vrbrowser/ui/widgets/Windows.java
@@ -207,6 +207,7 @@ public WindowWidget getFocusedWindow() {
         return mFocusedWindow;
     }
 
+    @NonNull
     public WindowWidget addWindow() {
         if (getCurrentWindows().size() >= MAX_WINDOWS) {
             return null;
@@ -290,12 +291,12 @@ public void closeWindow(@NonNull WindowWidget aWindow) {
 
         if (leftWindow == aWindow) {
             removeWindow(leftWindow);
-            if (mFocusedWindow == leftWindow) {
+            if (mFocusedWindow == leftWindow && frontWindow != null) {
                 focusWindow(frontWindow);
             }
         } else if (rightWindow == aWindow) {
             removeWindow(rightWindow);
-            if (mFocusedWindow == rightWindow) {
+            if (mFocusedWindow == rightWindow && frontWindow != null) {
                 focusWindow(frontWindow);
             }
         } else if (frontWindow == aWindow) {
@@ -306,8 +307,9 @@ public void closeWindow(@NonNull WindowWidget aWindow) {
                 placeWindow(leftWindow, WindowPlacement.FRONT);
             }
 
-            if (mFocusedWindow == frontWindow && !getCurrentWindows().isEmpty()) {
-                focusWindow(getFrontWindow());
+            frontWindow = getFrontWindow();
+            if (mFocusedWindow == frontWindow && !getCurrentWindows().isEmpty() && frontWindow != null) {
+                focusWindow(frontWindow);
             }
 
         }
@@ -337,7 +339,7 @@ public void moveWindowRight(@NonNull WindowWidget aWindow) {
         WindowWidget leftWindow = getLeftWindow();
         WindowWidget rightWindow = getRightWindow();
 
-        if (aWindow == leftWindow) {
+        if (aWindow == leftWindow && frontWindow != null) {
             placeWindow(leftWindow, WindowPlacement.FRONT);
             placeWindow(frontWindow, WindowPlacement.LEFT);
             switchTopBars(leftWindow, frontWindow);
@@ -362,7 +364,7 @@ public void moveWindowLeft(@NonNull WindowWidget aWindow) {
         WindowWidget leftWindow = getLeftWindow();
         WindowWidget rightWindow = getRightWindow();
 
-        if (aWindow == rightWindow) {
+        if (aWindow == rightWindow && frontWindow != null) {
             placeWindow(rightWindow, WindowPlacement.FRONT);
             placeWindow(frontWindow, WindowPlacement.RIGHT);
             switchTopBars(rightWindow, frontWindow);
@@ -522,7 +524,10 @@ public void enterPrivateMode() {
             }
 
         } else {
-            focusWindow(getWindowWithPlacement(mPrivateWindowPlacement));
+            WindowWidget window = getWindowWithPlacement(mRegularWindowPlacement);
+            if (window != null) {
+                focusWindow(window);
+            }
         }
         updateViews();
         mWidgetManager.pushWorldBrightness(this, WidgetManagerDelegate.DEFAULT_DIM_BRIGHTNESS);
@@ -546,7 +551,10 @@ public void exitPrivateMode() {
         for (WindowWidget window: mRegularWindows) {
             setWindowVisible(window, true);
         }
-        focusWindow(getWindowWithPlacement(mRegularWindowPlacement));
+        WindowWidget window = getWindowWithPlacement(mRegularWindowPlacement);
+        if (window != null) {
+            focusWindow(window);
+        }
         updateViews();
         mWidgetManager.popWorldBrightness(this);
     }
@@ -583,6 +591,7 @@ public ArrayList<WindowWidget> getCurrentWindows() {
         return mPrivateMode ? mPrivateWindows : mRegularWindows;
     }
 
+    @Nullable
     private WindowWidget getWindowWithPlacement(WindowPlacement aPlacement) {
         for (WindowWidget window: getCurrentWindows()) {
             if (window.getWindowPlacement() == aPlacement) {
@@ -592,6 +601,7 @@ private WindowWidget getWindowWithPlacement(WindowPlacement aPlacement) {
         return null;
     }
 
+    @Nullable
     private WindowWidget getFrontWindow() {
         if (mFullscreenWindow != null) {
             return mFullscreenWindow;
@@ -599,10 +609,12 @@ private WindowWidget getFrontWindow() {
         return getWindowWithPlacement(WindowPlacement.FRONT);
     }
 
+    @Nullable
     private WindowWidget getLeftWindow() {
         return getWindowWithPlacement(WindowPlacement.LEFT);
     }
 
+    @Nullable
     private WindowWidget getRightWindow() {
         return getWindowWithPlacement(WindowPlacement.RIGHT);
     }
@@ -849,6 +861,7 @@ private void updateTitleBars() {
         }
     }
 
+    @NonNull
     private WindowWidget createWindow(@Nullable Session aSession) {
         int newWindowId = sIndex++;
         WindowWidget window;
@@ -1027,7 +1040,9 @@ public void onMoveRightClicked(TopBarWidget aWidget) {
     // Title Bar Delegate
     @Override
     public void onTitleClicked(@NonNull TitleBarWidget titleBar) {
-        focusWindow(titleBar.getAttachedWindow());
+        if (titleBar.getAttachedWindow() != null) {
+            focusWindow(titleBar.getAttachedWindow());
+        }
     }
 
     @Override
@@ -1090,12 +1105,12 @@ private WindowWidget getWindowWithSession(Session aSession) {
 
     // WindowWidget.Delegate
     @Override
-    public void onFocusRequest(WindowWidget aWindow) {
+    public void onFocusRequest(@NonNull WindowWidget aWindow) {
         focusWindow(aWindow);
     }
 
     @Override
-    public void onBorderChanged(WindowWidget aWindow) {
+    public void onBorderChanged(@NonNull WindowWidget aWindow) {
         if (mDelegate != null) {
             mDelegate.onWindowBorderChanged(aWindow);
         }