From d46efb1d8414d9331f166d7147255752bf35bb2d Mon Sep 17 00:00:00 2001
From: Peter Serwylo <peter@serwylo.com>
Date: Mon, 21 Mar 2016 22:26:58 +1100
Subject: [PATCH] Correctly start and stop listening for repo update events
 during swap.

This fixes the following bugs:
 * `BroadcastReceiver` was never being created due to incorrect guard
   condition `if (pollForUpdatesReceiver != null)` (should have been
   `== null`).
 * Called `unregisterReceiver` rather than `registerReceiver`.
 * Even if it did work, it didn't make an effort to unregister the receiver.

In addition, the creation and listening with the `BroadcastReceiver is
now done in a way similar to the other swap views:
 * Create it as a `final` member variable.
 * `registerReceiver` when view is inflated.
 * `unregisterReceiver` when view is detached.
---
 .../fdroid/views/swap/SwapAppsView.java       | 72 ++++++++++---------
 1 file changed, 40 insertions(+), 32 deletions(-)

diff --git a/F-Droid/src/org/fdroid/fdroid/views/swap/SwapAppsView.java b/F-Droid/src/org/fdroid/fdroid/views/swap/SwapAppsView.java
index 6d955039f..399c8621e 100644
--- a/F-Droid/src/org/fdroid/fdroid/views/swap/SwapAppsView.java
+++ b/F-Droid/src/org/fdroid/fdroid/views/swap/SwapAppsView.java
@@ -118,10 +118,22 @@ public class SwapAppsView extends ListView implements
 
         displayImageOptions = Utils.getImageLoadingOptions().build();
 
+        LocalBroadcastManager.getInstance(getActivity()).registerReceiver(
+                pollForUpdatesReceiver, new IntentFilter(UpdateService.LOCAL_ACTION_STATUS));
+
         schedulePollForUpdates();
     }
 
-    private BroadcastReceiver pollForUpdatesReceiver;
+    /**
+     * Remove relevant listeners/receivers/etc so that they do not receive and process events
+     * when this view is not in use.
+     */
+    @Override
+    public void onDetachedFromWindow() {
+        super.onDetachedFromWindow();
+
+        LocalBroadcastManager.getInstance(getActivity()).unregisterReceiver(pollForUpdatesReceiver);
+    }
 
     private void pollForUpdates() {
         if (adapter.getCount() > 1 ||
@@ -132,37 +144,6 @@ public class SwapAppsView extends ListView implements
 
         Utils.debugLog(TAG, "Polling swap repo to see if it has any updates.");
         getActivity().getService().refreshSwap();
-        if (pollForUpdatesReceiver != null) {
-            pollForUpdatesReceiver = new BroadcastReceiver() {
-                @Override
-                public void onReceive(Context context, Intent intent) {
-                    int statusCode = intent.getIntExtra(UpdateService.EXTRA_STATUS_CODE, -1);
-                    switch (statusCode) {
-                        case UpdateService.STATUS_COMPLETE_WITH_CHANGES:
-                            Utils.debugLog(TAG, "Swap repo has updates, notifying the list adapter.");
-                            getActivity().runOnUiThread(new Runnable() {
-                                @Override
-                                public void run() {
-                                    adapter.notifyDataSetChanged();
-                                }
-                            });
-                            LocalBroadcastManager.getInstance(getActivity()).unregisterReceiver(pollForUpdatesReceiver);
-                            break;
-
-                        case UpdateService.STATUS_ERROR_GLOBAL:
-                            // TODO: Well, if we can't get the index, we probably can't swapp apps.
-                            // Tell the user somethign helpful?
-                            break;
-
-                        case UpdateService.STATUS_COMPLETE_AND_SAME:
-                            schedulePollForUpdates();
-                            break;
-                    }
-                }
-            };
-            // TODO: Unregister this properly, not just when successful (see swithc statement above)
-            LocalBroadcastManager.getInstance(getActivity()).unregisterReceiver(pollForUpdatesReceiver);
-        }
     }
 
     private void schedulePollForUpdates() {
@@ -486,4 +467,31 @@ public class SwapAppsView extends ListView implements
         }
     }
 
+    private final BroadcastReceiver pollForUpdatesReceiver = new BroadcastReceiver() {
+        @Override
+        public void onReceive(Context context, Intent intent) {
+            int statusCode = intent.getIntExtra(UpdateService.EXTRA_STATUS_CODE, -1);
+            switch (statusCode) {
+                case UpdateService.STATUS_COMPLETE_WITH_CHANGES:
+                    Utils.debugLog(TAG, "Swap repo has updates, notifying the list adapter.");
+                    getActivity().runOnUiThread(new Runnable() {
+                        @Override
+                        public void run() {
+                            adapter.notifyDataSetChanged();
+                        }
+                    });
+                    break;
+
+                case UpdateService.STATUS_ERROR_GLOBAL:
+                    // TODO: Well, if we can't get the index, we probably can't swapp apps.
+                    // Tell the user something helpful?
+                    break;
+
+                case UpdateService.STATUS_COMPLETE_AND_SAME:
+                    schedulePollForUpdates();
+                    break;
+            }
+        }
+    };
+
 }