From 9521b9a72cff2ea59c1759fa9807c0f87e5339f7 Mon Sep 17 00:00:00 2001
From: Peter Serwylo <peter@serwylo.com>
Date: Fri, 7 Apr 2017 16:05:52 +1000
Subject: [PATCH] Add guard contidion to prevent notifying when inappropriate.

Although the adapter tries to keep in sync with the app status update
manager, there may be times when this is not successful. In such
circumstances, it seems safe to just guard against invalid situations,
rather than trying to assert an error or fall over.

Fixes #922.
---
 .../fdroid/views/updates/UpdatesAdapter.java  | 20 +++++++++++--------
 1 file changed, 12 insertions(+), 8 deletions(-)

diff --git a/app/src/main/java/org/fdroid/fdroid/views/updates/UpdatesAdapter.java b/app/src/main/java/org/fdroid/fdroid/views/updates/UpdatesAdapter.java
index db2dc1824..b756cd3e6 100644
--- a/app/src/main/java/org/fdroid/fdroid/views/updates/UpdatesAdapter.java
+++ b/app/src/main/java/org/fdroid/fdroid/views/updates/UpdatesAdapter.java
@@ -316,7 +316,7 @@ public class UpdatesAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder
 
         // After adding the new item to our list (somewhere) we can then look it back up again in
         // order to notify the recycler view and scroll to that item.
-        int positionOfNewApp = 0;
+        int positionOfNewApp = -1;
         for (int i = 0; i < appsToShowStatus.size(); i++) {
             if (TextUtils.equals(appsToShowStatus.get(i).status.getUniqueKey(), apkUrl)) {
                 positionOfNewApp = i;
@@ -324,17 +324,19 @@ public class UpdatesAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder
             }
         }
 
-        notifyItemInserted(positionOfNewApp);
+        if (positionOfNewApp != -1) {
+            notifyItemInserted(positionOfNewApp);
 
-        if (recyclerView != null) {
-            recyclerView.smoothScrollToPosition(positionOfNewApp);
+            if (recyclerView != null) {
+                recyclerView.smoothScrollToPosition(positionOfNewApp);
+            }
         }
     }
 
     private void onAppStatusRemoved(String apkUrl) {
         // Find out where the item is in our internal data structure, so that we can remove it and
         // also notify the recycler view appropriately.
-        int positionOfOldApp = 0;
+        int positionOfOldApp = -1;
         for (int i = 0; i < appsToShowStatus.size(); i++) {
             if (TextUtils.equals(appsToShowStatus.get(i).status.getUniqueKey(), apkUrl)) {
                 positionOfOldApp = i;
@@ -342,10 +344,12 @@ public class UpdatesAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder
             }
         }
 
-        appsToShowStatus.remove(positionOfOldApp);
+        if (positionOfOldApp != -1) {
+            appsToShowStatus.remove(positionOfOldApp);
 
-        populateItems();
-        notifyItemRemoved(positionOfOldApp);
+            populateItems();
+            notifyItemRemoved(positionOfOldApp);
+        }
     }
 
     private final BroadcastReceiver receiverAppStatusChanges = new BroadcastReceiver() {