More null checks. Catch null exception in accessibility service.

src/Android/Android.csproj

@@ -17,7 +17,7 @@
     <GenerateSerializationAssemblies>Off</GenerateSerializationAssemblies>
     <AndroidManifest>Properties\AndroidManifest.xml</AndroidManifest>
     <AndroidUseLatestPlatformSdk>True</AndroidUseLatestPlatformSdk>
-    <TargetFrameworkVersion>v6.0</TargetFrameworkVersion>
+    <TargetFrameworkVersion>v7.1</TargetFrameworkVersion>
     <AndroidSupportedAbis>armeabi,armeabi-v7a,x86</AndroidSupportedAbis>
     <AndroidStoreUncompressedFileExtensions />
     <MandroidI18n />

src/Android/AutofillService.cs

@@ -52,6 +52,8 @@ namespace Bit.Android
         }.ToDictionary(n => n.PackageName);
 
         public override void OnAccessibilityEvent(AccessibilityEvent e)
+        {
+            try
             {
                 var root = RootInActiveWindow;
                 if(e == null || root == null || string.IsNullOrWhiteSpace(e.PackageName) ||
@@ -92,9 +94,7 @@ namespace Bit.Android
                                     FillCredentials(usernameEditText, passwordNodes);
 
                                     allEditTexts.Dispose();
-                                //allEditTexts = null;
                                     usernameEditText.Dispose();
-                                //usernameEditText = null;
                                 }
                                 else
                                 {
@@ -107,7 +107,6 @@ namespace Bit.Android
                         }
 
                         passwordNodes.Dispose();
-                    //passwordNodes = null;
 
                         if(cancelNotification)
                         {
@@ -119,11 +118,12 @@ namespace Bit.Android
                 }
 
                 notificationManager?.Dispose();
-            //notificationManager = null;
                 root.Dispose();
-            //root = null;
                 e.Dispose();
             }
+            // Some unknown condition is causing NullReferenceException's in production. Suppress it for now.
+            catch(NullReferenceException) { }
+        }
 
         public override void OnInterrupt()
         {
@@ -141,7 +141,6 @@ namespace Bit.Android
                 {
                     uri = ExtractUri(uri, addressNode, SupportedBrowsers[root.PackageName]);
                     addressNode.Dispose();
-                    //addressNode = null;
                 }
             }
 
@@ -233,7 +232,6 @@ namespace Bit.Android
             notificationManager.Notify(AutoFillNotificationId, builder.Build());
 
             builder.Dispose();
-            //builder = null;
         }
 
         private void FillCredentials(AccessibilityNodeInfo usernameNode, IEnumerable<AccessibilityNodeInfo> passwordNodes)

src/Android/Properties/AndroidManifest.xml

@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="utf-8"?>
-<manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.x8bit.bitwarden" android:versionName="1.4.2" android:installLocation="auto" android:versionCode="101">
+<manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.x8bit.bitwarden" android:versionName="1.4.3" android:installLocation="auto" android:versionCode="502">
   <uses-sdk android:minSdkVersion="19" android:targetSdkVersion="23" />
   <uses-permission android:name="android.permission.INTERNET" />
   <uses-permission android:name="android.permission.USE_FINGERPRINT" />

src/App/Pages/Vault/VaultEditLoginPage.cs

@@ -213,30 +213,50 @@ namespace Bit.App.Pages
                 AlertNoConnection();
             }
 
-            PasswordCell.InitEvents();
+            PasswordCell?.InitEvents();
-            UsernameCell.InitEvents();
+            UsernameCell?.InitEvents();
-            UriCell.InitEvents();
+            UriCell?.InitEvents();
-            NameCell.InitEvents();
+            NameCell?.InitEvents();
-            NotesCell.InitEvents();
+            NotesCell?.InitEvents();
-            FolderCell.InitEvents();
+            FolderCell?.InitEvents();
+
+            if(PasswordCell?.Button != null)
+            {
                 PasswordCell.Button.Clicked += PasswordButton_Clicked;
+            }
+            if(GenerateCell != null)
+            {
                 GenerateCell.Tapped += GenerateCell_Tapped;
+            }
+            if(DeleteCell != null)
+            {
                 DeleteCell.Tapped += DeleteCell_Tapped;
             }
+        }
 
         protected override void OnDisappearing()
         {
             base.OnDisappearing();
-            PasswordCell.Dispose();
+            PasswordCell?.Dispose();
-            UsernameCell.Dispose();
+            UsernameCell?.Dispose();
-            UriCell.Dispose();
+            UriCell?.Dispose();
-            NameCell.Dispose();
+            NameCell?.Dispose();
-            NotesCell.Dispose();
+            NotesCell?.Dispose();
-            FolderCell.Dispose();
+            FolderCell?.Dispose();
+
+            if(PasswordCell?.Button != null)
+            {
                 PasswordCell.Button.Clicked -= PasswordButton_Clicked;
+            }
+            if(GenerateCell != null)
+            {
                 GenerateCell.Tapped -= GenerateCell_Tapped;
+            }
+            if(DeleteCell != null)
+            {
                 DeleteCell.Tapped -= DeleteCell_Tapped;
             }
+        }
 
         private void PasswordButton_Clicked(object sender, EventArgs e)
         {

test/Android.Test/Android.Test.csproj

@@ -16,7 +16,7 @@
     <AndroidResgenFile>Resources\Resource.Designer.cs</AndroidResgenFile>
     <GenerateSerializationAssemblies>Off</GenerateSerializationAssemblies>
     <AndroidUseLatestPlatformSdk>True</AndroidUseLatestPlatformSdk>
-    <TargetFrameworkVersion>v6.0</TargetFrameworkVersion>
+    <TargetFrameworkVersion>v7.1</TargetFrameworkVersion>
     <AndroidManifest>Properties\AndroidManifest.xml</AndroidManifest>
   </PropertyGroup>
   <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Debug|AnyCPU' ">