Replace some of the most annoying AsyncTasks with RxJava

8 files changed, 283 insertions, 357 deletions

diff --git a/app/src/main/java/de/danoeh/antennapod/fragment/AllEpisodesFragment.java b/app/src/main/java/de/danoeh/antennapod/fragment/AllEpisodesFragment.java
index 5d0edb638..5aed66013 100644
--- a/app/src/main/java/de/danoeh/antennapod/fragment/AllEpisodesFragment.java
+++ b/app/src/main/java/de/danoeh/antennapod/fragment/AllEpisodesFragment.java
@@ -4,10 +4,10 @@ import android.app.Activity;
 import android.content.Context;
 import android.content.DialogInterface;
 import android.content.SharedPreferences;
-import android.os.AsyncTask;
 import android.os.Bundle;
 import android.os.Handler;
 import android.support.v4.app.Fragment;
+import android.support.v4.util.Pair;
 import android.support.v4.view.MenuItemCompat;
 import android.support.v7.widget.SearchView;
 import android.util.Log;
@@ -38,7 +38,6 @@ import de.danoeh.antennapod.core.feed.EventDistributor;
 import de.danoeh.antennapod.core.feed.Feed;
 import de.danoeh.antennapod.core.feed.FeedItem;
 import de.danoeh.antennapod.core.feed.FeedMedia;
-import de.danoeh.antennapod.core.feed.QueueEvent;
 import de.danoeh.antennapod.core.service.download.DownloadService;
 import de.danoeh.antennapod.core.service.download.Downloader;
 import de.danoeh.antennapod.core.storage.DBReader;
@@ -49,6 +48,10 @@ import de.danoeh.antennapod.core.storage.DownloadRequester;
 import de.danoeh.antennapod.core.util.LongList;
 import de.danoeh.antennapod.menuhandler.FeedItemMenuHandler;
 import de.danoeh.antennapod.menuhandler.MenuItemUtils;
+import rx.Observable;
+import rx.Subscription;
+import rx.android.schedulers.AndroidSchedulers;
+import rx.schedulers.Schedulers;
 
 /**
  * Shows unread or recently published episodes
@@ -90,6 +93,8 @@ public class AllEpisodesFragment extends Fragment {
 
     private boolean isUpdatingFeeds;
 
+    protected Subscription subscription;
+
     public AllEpisodesFragment() {
         // by default we show all the episodes
         this(false, DEFAULT_PREF_NAME);
@@ -113,7 +118,7 @@ public class AllEpisodesFragment extends Fragment {
     @Override
     public void onResume() {
         super.onResume();
-        startItemLoader();
+        loadItems();
     }
 
     @Override
@@ -140,7 +145,9 @@ public class AllEpisodesFragment extends Fragment {
     public void onStop() {
         super.onStop();
         EventDistributor.getInstance().unregister(contentUpdate);
-        stopItemLoader();
+        if(subscription != null) {
+            subscription.unsubscribe();
+        }
     }
 
     @Override
@@ -436,7 +443,7 @@ public class AllEpisodesFragment extends Fragment {
         @Override
         public void update(EventDistributor eventDistributor, Integer arg) {
             if ((arg & EVENTS) != 0) {
-                startItemLoader();
+                loadItems();
                 if (isUpdatingFeeds != updateRefreshMenuItemChecker.isRefreshing()) {
                     getActivity().supportInvalidateOptionsMenu();
                 }
@@ -453,69 +460,43 @@ public class AllEpisodesFragment extends Fragment {
         }
     }
 
-    private ItemLoader itemLoader;
-
-    protected void startItemLoader() {
-        if (itemLoader != null) {
-            itemLoader.cancel(true);
+    protected void loadItems() {
+        if(subscription != null) {
+            subscription.unsubscribe();
         }
-        itemLoader = new ItemLoader();
-        itemLoader.execute();
-    }
-
-    protected void stopItemLoader() {
-        if (itemLoader != null) {
-            itemLoader.cancel(true);
+        if (viewsCreated && !itemsLoaded) {
+            listView.setVisibility(View.GONE);
+            txtvEmpty.setVisibility(View.GONE);
+            progLoading.setVisibility(View.VISIBLE);
         }
+        subscription = Observable.defer(() -> Observable.just(loadData()))
+                .subscribeOn(Schedulers.newThread())
+                .observeOn(AndroidSchedulers.mainThread())
+                .subscribe(data -> {
+                    listView.setVisibility(View.VISIBLE);
+                    progLoading.setVisibility(View.GONE);
+                    if (data != null) {
+                        episodes = data.first;
+                        queuedItemsIds = data.second;
+                        itemsLoaded = true;
+                        if (viewsCreated && activity.get() != null) {
+                            onFragmentLoaded();
+                        }
+                    }
+                }, error -> {
+                    Log.e(TAG, Log.getStackTraceString(error));
+                });
     }
 
-    private class ItemLoader extends AsyncTask<Void, Void, Object[]> {
-
-        @Override
-        protected void onPreExecute() {
-            super.onPreExecute();
-            if (viewsCreated && !itemsLoaded) {
-                listView.setVisibility(View.GONE);
-                txtvEmpty.setVisibility(View.GONE);
-                progLoading.setVisibility(View.VISIBLE);
-            }
-        }
-
-        @Override
-        protected Object[] doInBackground(Void... params) {
-            Context context = activity.get();
-            if (context != null) {
-                if(showOnlyNewEpisodes) {
-                    return new Object[] {
-                            DBReader.getNewItemsList(),
-                            DBReader.getQueueIDList(),
-                            null // see ItemAccess.isNew
-                    };
-                } else {
-                    return new Object[]{
-                            DBReader.getRecentlyPublishedEpisodes(RECENT_EPISODES_LIMIT),
-                            DBReader.getQueueIDList()
-                    };
-                }
-            } else {
-                return null;
-            }
-        }
-
-        @Override
-        protected void onPostExecute(Object[] lists) {
-            super.onPostExecute(lists);
-            listView.setVisibility(View.VISIBLE);
-            progLoading.setVisibility(View.GONE);
-
-            if (lists != null) {
-                episodes = (List<FeedItem>) lists[0];
-                queuedItemsIds = (LongList) lists[1];
-                itemsLoaded = true;
-                if (viewsCreated && activity.get() != null) {
-                    onFragmentLoaded();
-                }
-            }
+    private Pair<List<FeedItem>,LongList> loadData() {
+        List<FeedItem> items;
+        if(showOnlyNewEpisodes) {
+            items = DBReader.getNewItemsList();
+        } else {
+            items = DBReader.getRecentlyPublishedEpisodes(RECENT_EPISODES_LIMIT);
         }
+        LongList queuedIds = DBReader.getQueueIDList();
+        return Pair.create(items, queuedIds);
     }
+
 }
diff --git a/app/src/main/java/de/danoeh/antennapod/fragment/CompletedDownloadsFragment.java b/app/src/main/java/de/danoeh/antennapod/fragment/CompletedDownloadsFragment.java
index 278928f3d..c5b582d3a 100644
--- a/app/src/main/java/de/danoeh/antennapod/fragment/CompletedDownloadsFragment.java
+++ b/app/src/main/java/de/danoeh/antennapod/fragment/CompletedDownloadsFragment.java
@@ -1,14 +1,12 @@
 package de.danoeh.antennapod.fragment;
 
 import android.app.Activity;
-import android.content.Context;
-import android.os.AsyncTask;
 import android.os.Bundle;
 import android.support.v4.app.ListFragment;
+import android.util.Log;
 import android.view.View;
 import android.widget.ListView;
 
-import java.util.Collections;
 import java.util.List;
 
 import de.danoeh.antennapod.R;
@@ -18,11 +16,18 @@ import de.danoeh.antennapod.core.feed.EventDistributor;
 import de.danoeh.antennapod.core.feed.FeedItem;
 import de.danoeh.antennapod.core.storage.DBReader;
 import de.danoeh.antennapod.core.storage.DBWriter;
+import rx.Observable;
+import rx.Subscription;
+import rx.android.schedulers.AndroidSchedulers;
+import rx.schedulers.Schedulers;
 
 /**
  * Displays all running downloads and provides a button to delete them
  */
 public class CompletedDownloadsFragment extends ListFragment {
+
+    private static final String TAG = CompletedDownloadsFragment.class.getSimpleName();
+
     private static final int EVENTS =
             EventDistributor.DOWNLOAD_HANDLED |
                     EventDistributor.DOWNLOADLOG_UPDATE |
@@ -34,11 +39,12 @@ public class CompletedDownloadsFragment extends ListFragment {
     private boolean viewCreated = false;
     private boolean itemsLoaded = false;
 
+    private Subscription subscription;
+
     @Override
     public void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
-
-        startItemLoader();
+        loadItems();
     }
 
     @Override
@@ -51,13 +57,17 @@ public class CompletedDownloadsFragment extends ListFragment {
     public void onStop() {
         super.onStop();
         EventDistributor.getInstance().unregister(contentUpdate);
-        stopItemLoader();
+        if(subscription != null) {
+            subscription.unsubscribe();
+        }
     }
 
     @Override
     public void onDetach() {
         super.onDetach();
-        stopItemLoader();
+        if(subscription != null) {
+            subscription.unsubscribe();
+        }
     }
 
     @Override
@@ -65,7 +75,9 @@ public class CompletedDownloadsFragment extends ListFragment {
         super.onDestroyView();
         listAdapter = null;
         viewCreated = false;
-        stopItemLoader();
+        if(subscription != null) {
+            subscription.unsubscribe();
+        }
     }
 
     @Override
@@ -132,56 +144,32 @@ public class CompletedDownloadsFragment extends ListFragment {
         @Override
         public void update(EventDistributor eventDistributor, Integer arg) {
             if ((arg & EVENTS) != 0) {
-                startItemLoader();
+                loadItems();
             }
         }
     };
 
-    private ItemLoader itemLoader;
-
-    private void startItemLoader() {
-        if (itemLoader != null) {
-            itemLoader.cancel(true);
+    private void loadItems() {
+        if(subscription != null) {
+            subscription.unsubscribe();
         }
-        itemLoader = new ItemLoader();
-        itemLoader.execute();
-    }
-
-    private void stopItemLoader() {
-        if (itemLoader != null) {
-            itemLoader.cancel(true);
+        if (!itemsLoaded && viewCreated) {
+            setListShown(false);
         }
+        subscription = Observable.defer(() -> Observable.just(DBReader.getDownloadedItems()))
+                .subscribeOn(Schedulers.newThread())
+                .observeOn(AndroidSchedulers.mainThread())
+                .subscribe(result -> {
+                    if (result != null) {
+                        items = result;
+                        itemsLoaded = true;
+                        if (viewCreated && getActivity() != null) {
+                            onFragmentLoaded();
+                        }
+                    }
+                }, error -> {
+                    Log.e(TAG, Log.getStackTraceString(error));
+                });
     }
 
-    private class ItemLoader extends AsyncTask<Void, Void, List<FeedItem>> {
-
-        @Override
-        protected void onPreExecute() {
-            super.onPreExecute();
-            if (!itemsLoaded && viewCreated) {
-                setListShown(false);
-            }
-        }
-
-        @Override
-        protected void onPostExecute(List<FeedItem> results) {
-            super.onPostExecute(results);
-            if (results != null) {
-                items = results;
-                itemsLoaded = true;
-                if (viewCreated && getActivity() != null) {
-                    onFragmentLoaded();
-                }
-            }
-        }
-
-        @Override
-        protected List<FeedItem> doInBackground(Void... params) {
-            Context context = getActivity();
-            if (context != null) {
-                return DBReader.getDownloadedItems();
-            }
-            return Collections.emptyList();
-        }
-    }
 }
diff --git a/app/src/main/java/de/danoeh/antennapod/fragment/DownloadLogFragment.java b/app/src/main/java/de/danoeh/antennapod/fragment/DownloadLogFragment.java
index da2c05a69..669c6ac49 100644
--- a/app/src/main/java/de/danoeh/antennapod/fragment/DownloadLogFragment.java
+++ b/app/src/main/java/de/danoeh/antennapod/fragment/DownloadLogFragment.java
@@ -1,11 +1,10 @@
 package de.danoeh.antennapod.fragment;
 
-import android.content.Context;
 import android.content.res.TypedArray;
-import android.os.AsyncTask;
 import android.os.Bundle;
 import android.support.v4.app.ListFragment;
 import android.support.v4.view.MenuItemCompat;
+import android.util.Log;
 import android.view.Menu;
 import android.view.MenuInflater;
 import android.view.MenuItem;
@@ -20,6 +19,10 @@ import de.danoeh.antennapod.core.feed.EventDistributor;
 import de.danoeh.antennapod.core.service.download.DownloadStatus;
 import de.danoeh.antennapod.core.storage.DBReader;
 import de.danoeh.antennapod.core.storage.DBWriter;
+import rx.Observable;
+import rx.Subscription;
+import rx.android.schedulers.AndroidSchedulers;
+import rx.schedulers.Schedulers;
 
 /**
  * Shows the download log
@@ -34,19 +37,23 @@ public class DownloadLogFragment extends ListFragment {
     private boolean viewsCreated = false;
     private boolean itemsLoaded = false;
 
+    private Subscription subscription;
+
     @Override
     public void onStart() {
         super.onStart();
         setHasOptionsMenu(true);
         EventDistributor.getInstance().register(contentUpdate);
-        startItemLoader();
+        loadItems();
     }
 
     @Override
     public void onStop() {
         super.onStop();
         EventDistributor.getInstance().unregister(contentUpdate);
-        stopItemLoader();
+        if(subscription != null) {
+            subscription.unsubscribe();
+        }
     }
 
     @Override
@@ -93,27 +100,11 @@ public class DownloadLogFragment extends ListFragment {
         @Override
         public void update(EventDistributor eventDistributor, Integer arg) {
             if ((arg & EventDistributor.DOWNLOADLOG_UPDATE) != 0) {
-                startItemLoader();
+                loadItems();
             }
         }
     };
 
-    private ItemLoader itemLoader;
-
-    private void startItemLoader() {
-        if (itemLoader != null) {
-            itemLoader.cancel(true);
-        }
-        itemLoader = new ItemLoader();
-        itemLoader.execute();
-    }
-
-    private void stopItemLoader() {
-        if (itemLoader != null) {
-            itemLoader.cancel(true);
-        }
-    }
-
     @Override
     public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
         super.onCreateOptionsMenu(menu, inflater);
@@ -152,27 +143,24 @@ public class DownloadLogFragment extends ListFragment {
         }
     }
 
-    private class ItemLoader extends AsyncTask<Void, Void, List<DownloadStatus>> {
-
-        @Override
-        protected void onPostExecute(List<DownloadStatus> downloadStatuses) {
-            super.onPostExecute(downloadStatuses);
-            if (downloadStatuses != null) {
-                downloadLog = downloadStatuses;
-                itemsLoaded = true;
-                if (viewsCreated) {
-                    onFragmentLoaded();
-                }
-            }
-        }
-
-        @Override
-        protected List<DownloadStatus> doInBackground(Void... params) {
-            Context context = getActivity();
-            if (context != null) {
-                return DBReader.getDownloadLog();
-            }
-            return null;
+    private void loadItems() {
+        if(subscription != null) {
+            subscription.unsubscribe();
         }
+        subscription = Observable.defer(() -> Observable.just(DBReader.getDownloadLog()))
+                .subscribeOn(Schedulers.newThread())
+                .observeOn(AndroidSchedulers.mainThread())
+                .subscribe(result -> {
+                    if (result != null) {
+                        downloadLog = result;
+                        itemsLoaded = true;
+                        if (viewsCreated) {
+                            onFragmentLoaded();
+                        }
+                    }
+                }, error -> {
+                    Log.e(TAG, Log.getStackTraceString(error));
+                });
     }
+
 }
diff --git a/app/src/main/java/de/danoeh/antennapod/fragment/ItemlistFragment.java b/app/src/main/java/de/danoeh/antennapod/fragment/ItemlistFragment.java
index 38c9b645a..3d0ff66f7 100644
--- a/app/src/main/java/de/danoeh/antennapod/fragment/ItemlistFragment.java
+++ b/app/src/main/java/de/danoeh/antennapod/fragment/ItemlistFragment.java
@@ -7,12 +7,12 @@ import android.content.Intent;
 import android.content.res.TypedArray;
 import android.graphics.Color;
 import android.graphics.LightingColorFilter;
-import android.os.AsyncTask;
 import android.os.Build;
 import android.os.Bundle;
 import android.os.Handler;
 import android.support.v4.app.Fragment;
 import android.support.v4.app.ListFragment;
+import android.support.v4.util.Pair;
 import android.support.v4.view.MenuItemCompat;
 import android.support.v7.app.ActionBarActivity;
 import android.support.v7.widget.SearchView;
@@ -73,6 +73,10 @@ import de.danoeh.antennapod.menuhandler.FeedItemMenuHandler;
 import de.danoeh.antennapod.menuhandler.FeedMenuHandler;
 import de.danoeh.antennapod.menuhandler.MenuItemUtils;
 import de.greenrobot.event.EventBus;
+import rx.Observable;
+import rx.Subscription;
+import rx.android.schedulers.AndroidSchedulers;
+import rx.schedulers.Schedulers;
 
 /**
  * Displays a list of FeedItems.
@@ -111,6 +115,8 @@ public class ItemlistFragment extends ListFragment {
 
     private TextView txtvInformation;
 
+    private Subscription subscription;
+
     /**
      * Creates new ItemlistFragment which shows the Feeditems of a specific
      * feed. Sets 'showFeedtitle' to false
@@ -156,7 +162,9 @@ public class ItemlistFragment extends ListFragment {
         super.onStop();
         EventDistributor.getInstance().unregister(contentUpdate);
         EventBus.getDefault().unregister(this);
-        stopItemLoader();
+        if(subscription != null) {
+            subscription.unsubscribe();
+        }
     }
 
     @Override
@@ -164,13 +172,15 @@ public class ItemlistFragment extends ListFragment {
         super.onResume();
         Log.d(TAG, "onResume()");
         updateProgressBarVisibility();
-        startItemLoader();
+        loadItems();
     }
 
     @Override
     public void onDetach() {
         super.onDetach();
-        stopItemLoader();
+        if(subscription != null) {
+            subscription.unsubscribe();
+        }
     }
 
     @Override
@@ -385,13 +395,13 @@ public class ItemlistFragment extends ListFragment {
 
     public void onEvent(QueueEvent event) {
         Log.d(TAG, "onEvent(" + event + ")");
-        startItemLoader();
+        loadItems();
     }
 
     public void onEvent(FeedEvent event) {
         Log.d(TAG, "onEvent(" + event + ")");
         if(event.feedId == feedID) {
-            startItemLoader();
+            loadItems();
         }
     }
 
@@ -404,7 +414,7 @@ public class ItemlistFragment extends ListFragment {
                 if ((EventDistributor.DOWNLOAD_QUEUED & arg) != 0) {
                     updateProgressBarVisibility();
                 } else {
-                    startItemLoader();
+                    loadItems();
                     updateProgressBarVisibility();
                 }
             }
@@ -608,51 +618,37 @@ public class ItemlistFragment extends ListFragment {
         }
     };
 
-    private ItemLoader itemLoader;
 
-    private void startItemLoader() {
-        if (itemLoader != null) {
-            itemLoader.cancel(true);
+    private void loadItems() {
+        if(subscription != null) {
+            subscription.unsubscribe();
         }
-        itemLoader = new ItemLoader();
-        itemLoader.execute(feedID);
-    }
 
-    private void stopItemLoader() {
-        if (itemLoader != null) {
-            itemLoader.cancel(true);
-        }
+        subscription = Observable.defer(() -> Observable.just(loadData()))
+                .subscribeOn(Schedulers.newThread())
+                .observeOn(AndroidSchedulers.mainThread())
+                .subscribe(result -> {
+                    if (result != null) {
+                        feed = result.first;
+                        queuedItemsIds = result.second;
+                        itemsLoaded = true;
+                        if (viewsCreated) {
+                            onFragmentLoaded();
+                        }
+                    }
+                }, error -> {
+                    Log.e(TAG, Log.getStackTraceString(error));
+                });
     }
 
-    private class ItemLoader extends AsyncTask<Long, Void, Object[]> {
-        @Override
-        protected Object[] doInBackground(Long... params) {
-            long feedID = params[0];
-            Context context = getActivity();
-            if (context != null) {
-                Feed feed = DBReader.getFeed(feedID);
-                if(feed != null && feed.getItemFilter() != null) {
-                    FeedItemFilter filter = feed.getItemFilter();
-                    feed.setItems(filter.filter(context, feed.getItems()));
-                }
-                LongList queuedItemsIds = DBReader.getQueueIDList();
-                return new Object[] { feed, queuedItemsIds };
-            } else {
-                return null;
-            }
-        }
-
-        @Override
-        protected void onPostExecute(Object[] res) {
-            super.onPostExecute(res);
-            if (res != null) {
-                feed = (Feed) res[0];
-                queuedItemsIds = (LongList) res[1];
-                itemsLoaded = true;
-                if (viewsCreated) {
-                    onFragmentLoaded();
-                }
-            }
+    private Pair<Feed, LongList> loadData() {
+        Feed feed = DBReader.getFeed(feedID);
+        if(feed != null && feed.getItemFilter() != null) {
+            FeedItemFilter filter = feed.getItemFilter();
+            feed.setItems(filter.filter(feed.getItems()));
         }
+        LongList queuedItemsIds = DBReader.getQueueIDList();
+        return Pair.create(feed, queuedItemsIds);
     }
+
 }
diff --git a/app/src/main/java/de/danoeh/antennapod/fragment/NewEpisodesFragment.java b/app/src/main/java/de/danoeh/antennapod/fragment/NewEpisodesFragment.java
index 6177f2a50..d454208c1 100644
--- a/app/src/main/java/de/danoeh/antennapod/fragment/NewEpisodesFragment.java
+++ b/app/src/main/java/de/danoeh/antennapod/fragment/NewEpisodesFragment.java
@@ -39,7 +39,7 @@ public class NewEpisodesFragment extends AllEpisodesFragment {
 
     public void onEvent(QueueEvent event) {
         Log.d(TAG, "onEvent(" + event + ")");
-        startItemLoader();
+        loadItems();
     }
 
     @Override
@@ -69,7 +69,9 @@ public class NewEpisodesFragment extends AllEpisodesFragment {
             @Override
             public void remove(int which) {
                 Log.d(TAG, "remove(" + which + ")");
-                stopItemLoader();
+                if(subscription != null) {
+                    subscription.unsubscribe();
+                }
                 FeedItem item = (FeedItem) listView.getAdapter().getItem(which);
                 // we're marking it as unplayed since the user didn't actually play it
                 // but they don't want it considered 'NEW' anymore
diff --git a/app/src/main/java/de/danoeh/antennapod/fragment/PlaybackHistoryFragment.java b/app/src/main/java/de/danoeh/antennapod/fragment/PlaybackHistoryFragment.java
index 530883667..e6460309b 100644
--- a/app/src/main/java/de/danoeh/antennapod/fragment/PlaybackHistoryFragment.java
+++ b/app/src/main/java/de/danoeh/antennapod/fragment/PlaybackHistoryFragment.java
@@ -1,9 +1,7 @@
 package de.danoeh.antennapod.fragment;
 
 import android.app.Activity;
-import android.content.Context;
 import android.content.res.TypedArray;
-import android.os.AsyncTask;
 import android.os.Bundle;
 import android.os.Handler;
 import android.support.v4.app.ListFragment;
@@ -33,6 +31,10 @@ import de.danoeh.antennapod.core.storage.DBReader;
 import de.danoeh.antennapod.core.storage.DBWriter;
 import de.danoeh.antennapod.core.util.LongList;
 import de.greenrobot.event.EventBus;
+import rx.Observable;
+import rx.Subscription;
+import rx.android.schedulers.AndroidSchedulers;
+import rx.schedulers.Schedulers;
 
 public class PlaybackHistoryFragment extends ListFragment {
 
@@ -53,6 +55,8 @@ public class PlaybackHistoryFragment extends ListFragment {
     private DownloadObserver downloadObserver;
     private List<Downloader> downloaderList;
 
+    private Subscription subscription;
+
     @Override
     public void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
@@ -63,7 +67,7 @@ public class PlaybackHistoryFragment extends ListFragment {
     @Override
     public void onResume() {
         super.onResume();
-        startItemLoader();
+        loadItems();
     }
 
     @Override
@@ -78,13 +82,17 @@ public class PlaybackHistoryFragment extends ListFragment {
         super.onStop();
         EventDistributor.getInstance().unregister(contentUpdate);
         EventBus.getDefault().unregister(this);
-        stopItemLoader();
+        if(subscription != null) {
+            subscription.unsubscribe();
+        }
     }
 
     @Override
     public void onDetach() {
         super.onDetach();
-        stopItemLoader();
+        if(subscription != null) {
+            subscription.unsubscribe();
+        }
         activity.set(null);
     }
 
@@ -176,7 +184,7 @@ public class PlaybackHistoryFragment extends ListFragment {
 
     public void onEvent(QueueEvent event) {
         Log.d(TAG, "onEvent(" + event + ")");
-        startItemLoader();
+        loadItems();
     }
 
     private EventDistributor.EventListener contentUpdate = new EventDistributor.EventListener() {
@@ -184,7 +192,7 @@ public class PlaybackHistoryFragment extends ListFragment {
         @Override
         public void update(EventDistributor eventDistributor, Integer arg) {
             if ((arg & EVENTS) != 0) {
-                startItemLoader();
+                loadItems();
                 getActivity().supportInvalidateOptionsMenu();
             }
         }
@@ -245,48 +253,32 @@ public class PlaybackHistoryFragment extends ListFragment {
         }
     };
 
-    private ItemLoader itemLoader;
-
-    private void startItemLoader() {
-        if (itemLoader != null) {
-            itemLoader.cancel(true);
+    private void loadItems() {
+        if(subscription != null) {
+            subscription.unsubscribe();
         }
-        itemLoader = new ItemLoader();
-        itemLoader.execute();
+        subscription = Observable.defer(() -> Observable.just(loadData()))
+                .subscribeOn(Schedulers.newThread())
+                .observeOn(AndroidSchedulers.mainThread())
+                .subscribe(result -> {
+                    if (result != null) {
+                        playbackHistory = result.first;
+                        queue = result.second;
+                        itemsLoaded = true;
+                        if (viewsCreated) {
+                            onFragmentLoaded();
+                        }
+                    }
+                }, error -> {
+                    Log.e(TAG, Log.getStackTraceString(error));
+                });
     }
 
-    private void stopItemLoader() {
-        if (itemLoader != null) {
-            itemLoader.cancel(true);
-        }
+    private Pair<List<FeedItem>, LongList> loadData() {
+        List<FeedItem> history = DBReader.getPlaybackHistory();
+        LongList queue = DBReader.getQueueIDList();
+        DBReader.loadFeedDataOfFeedItemlist(history);
+        return Pair.create(history, queue);
     }
 
-    private class ItemLoader extends AsyncTask<Void, Void, Pair<List<FeedItem>,LongList>> {
-
-        @Override
-        protected Pair<List<FeedItem>,LongList> doInBackground(Void... params) {
-            Context context = activity.get();
-            if (context != null) {
-                List<FeedItem> history = DBReader.getPlaybackHistory();
-                LongList queue = DBReader.getQueueIDList();
-                DBReader.loadFeedDataOfFeedItemlist(history);
-                return Pair.create(history, queue);
-            } else {
-                return null;
-            }
-        }
-
-        @Override
-        protected void onPostExecute(Pair<List<FeedItem>,LongList> res) {
-            super.onPostExecute(res);
-            if (res != null) {
-                playbackHistory = res.first;
-                queue = res.second;
-                itemsLoaded = true;
-                if (viewsCreated) {
-                    onFragmentLoaded();
-                }
-            }
-        }
-    }
 }
diff --git a/app/src/main/java/de/danoeh/antennapod/fragment/QueueFragment.java b/app/src/main/java/de/danoeh/antennapod/fragment/QueueFragment.java
index 63c319e03..7bcd98dc8 100644
--- a/app/src/main/java/de/danoeh/antennapod/fragment/QueueFragment.java
+++ b/app/src/main/java/de/danoeh/antennapod/fragment/QueueFragment.java
@@ -4,7 +4,6 @@ import android.app.Activity;
 import android.content.Context;
 import android.content.DialogInterface;
 import android.content.SharedPreferences;
-import android.os.AsyncTask;
 import android.os.Bundle;
 import android.os.Handler;
 import android.support.v4.app.Fragment;
@@ -55,6 +54,10 @@ import de.danoeh.antennapod.core.util.gui.UndoBarController;
 import de.danoeh.antennapod.menuhandler.FeedItemMenuHandler;
 import de.danoeh.antennapod.menuhandler.MenuItemUtils;
 import de.greenrobot.event.EventBus;
+import rx.Observable;
+import rx.Subscription;
+import rx.android.schedulers.AndroidSchedulers;
+import rx.schedulers.Schedulers;
 
 /**
  * Shows all items in the queue
@@ -98,6 +101,8 @@ public class QueueFragment extends Fragment {
      */
     private boolean blockDownloadObserverUpdate = false;
 
+    private Subscription subscription;
+
 
     @Override
     public void onCreate(Bundle savedInstanceState) {
@@ -109,7 +114,7 @@ public class QueueFragment extends Fragment {
     @Override
     public void onResume() {
         super.onResume();
-        startItemLoader();
+        loadItems();
     }
 
     @Override
@@ -138,7 +143,9 @@ public class QueueFragment extends Fragment {
         super.onStop();
         EventDistributor.getInstance().unregister(contentUpdate);
         EventBus.getDefault().unregister(this);
-        stopItemLoader();
+        if(subscription != null) {
+            subscription.unsubscribe();
+        }
         if(undoBarController.isShowing()) {
             undoBarController.close();
         }
@@ -156,7 +163,7 @@ public class QueueFragment extends Fragment {
             undoBarController.showUndoBar(false, getString(R.string.removed_from_queue),
                     new FeedItemUndoToken(event.item, event.position));
         }
-        startItemLoader();
+        loadItems();
     }
 
     private void saveScrollPosition() {
@@ -398,7 +405,9 @@ public class QueueFragment extends Fragment {
             public void drop(int from, int to) {
                 Log.d(TAG, "drop");
                 blockDownloadObserverUpdate = false;
-                stopItemLoader();
+                if(subscription != null) {
+                    subscription.unsubscribe();
+                }
                 final FeedItem item = queue.remove(from);
                 queue.add(to, item);
                 listAdapter.notifyDataSetChanged();
@@ -408,7 +417,9 @@ public class QueueFragment extends Fragment {
             @Override
             public void remove(int which) {
                 Log.d(TAG, "remove(" + which + ")");
-                stopItemLoader();
+                if(subscription != null) {
+                    subscription.unsubscribe();
+                }
                 FeedItem item = (FeedItem) listView.getAdapter().getItem(which);
                 DBWriter.removeQueueItem(getActivity(), item, true);
             }
@@ -556,7 +567,7 @@ public class QueueFragment extends Fragment {
         @Override
         public void update(EventDistributor eventDistributor, Integer arg) {
             if ((arg & EVENTS) != 0) {
-                startItemLoader();
+                loadItems();
                 if (isUpdatingFeeds != updateRefreshMenuItemChecker.isRefreshing()) {
                     getActivity().supportInvalidateOptionsMenu();
                 }
@@ -564,55 +575,31 @@ public class QueueFragment extends Fragment {
         }
     };
 
-    private ItemLoader itemLoader;
-
-    private void startItemLoader() {
-        if (itemLoader != null) {
-            itemLoader.cancel(true);
+    private void loadItems() {
+        if(subscription != null) {
+            subscription.unsubscribe();
         }
-        itemLoader = new ItemLoader();
-        itemLoader.execute();
-    }
-
-    private void stopItemLoader() {
-        if (itemLoader != null) {
-            itemLoader.cancel(true);
+        if (viewsCreated && !itemsLoaded) {
+            listView.setVisibility(View.GONE);
+            txtvEmpty.setVisibility(View.GONE);
+            progLoading.setVisibility(View.VISIBLE);
         }
+        subscription = Observable.defer(() -> Observable.just(DBReader.getQueue()))
+                .subscribeOn(Schedulers.newThread())
+                .observeOn(AndroidSchedulers.mainThread())
+                .subscribe(result -> {
+                    listView.setVisibility(View.VISIBLE);
+                    progLoading.setVisibility(View.GONE);
+                    if(result != null) {
+                        queue = result;
+                        itemsLoaded = true;
+                        if (viewsCreated && activity.get() != null) {
+                            onFragmentLoaded();
+                        }
+                    }
+                }, error -> {
+                    Log.e(TAG, Log.getStackTraceString(error));
+                });
     }
 
-    private class ItemLoader extends AsyncTask<Void, Void, List<FeedItem>> {
-        @Override
-        protected void onPreExecute() {
-            super.onPreExecute();
-            if (viewsCreated && !itemsLoaded) {
-                listView.setVisibility(View.GONE);
-                txtvEmpty.setVisibility(View.GONE);
-                progLoading.setVisibility(View.VISIBLE);
-            }
-        }
-
-        @Override
-        protected void onPostExecute(List<FeedItem> feedItems) {
-            super.onPostExecute(feedItems);
-            listView.setVisibility(View.VISIBLE);
-            progLoading.setVisibility(View.GONE);
-
-            if (feedItems != null) {
-                queue = feedItems;
-                itemsLoaded = true;
-                if (viewsCreated && activity.get() != null) {
-                    onFragmentLoaded();
-                }
-            }
-        }
-
-        @Override
-        protected List<FeedItem> doInBackground(Void... params) {
-            Context context = activity.get();
-            if (context != null) {
-                return DBReader.getQueue();
-            }
-            return null;
-        }
-    }
 }
diff --git a/app/src/main/java/de/danoeh/antennapod/fragment/SearchFragment.java b/app/src/main/java/de/danoeh/antennapod/fragment/SearchFragment.java
index 975493ce9..edd8cdd1a 100644
--- a/app/src/main/java/de/danoeh/antennapod/fragment/SearchFragment.java
+++ b/app/src/main/java/de/danoeh/antennapod/fragment/SearchFragment.java
@@ -1,19 +1,18 @@
 package de.danoeh.antennapod.fragment;
 
 import android.content.Context;
-import android.os.AsyncTask;
 import android.os.Bundle;
 import android.support.v4.app.ListFragment;
 import android.support.v4.view.MenuItemCompat;
 import android.support.v7.app.ActionBarActivity;
 import android.support.v7.widget.SearchView;
+import android.util.Log;
 import android.view.Menu;
 import android.view.MenuInflater;
 import android.view.MenuItem;
 import android.view.View;
 import android.widget.ListView;
 
-import java.util.Collections;
 import java.util.List;
 
 import de.danoeh.antennapod.R;
@@ -25,6 +24,10 @@ import de.danoeh.antennapod.core.feed.FeedComponent;
 import de.danoeh.antennapod.core.feed.FeedItem;
 import de.danoeh.antennapod.core.feed.SearchResult;
 import de.danoeh.antennapod.core.storage.FeedSearcher;
+import rx.Observable;
+import rx.Subscription;
+import rx.android.schedulers.AndroidSchedulers;
+import rx.schedulers.Schedulers;
 
 /**
  * Performs a search operation on all feeds or one specific feed and displays the search result.
@@ -41,6 +44,8 @@ public class SearchFragment extends ListFragment {
     private boolean viewCreated = false;
     private boolean itemsLoaded = false;
 
+    private Subscription subscription;
+
     /**
      * Create a new SearchFragment that searches all feeds.
      */
@@ -68,7 +73,7 @@ public class SearchFragment extends ListFragment {
         super.onCreate(savedInstanceState);
         setRetainInstance(true);
         setHasOptionsMenu(true);
-        startSearchTask();
+        search();
     }
 
     @Override
@@ -80,14 +85,18 @@ public class SearchFragment extends ListFragment {
     @Override
     public void onStop() {
         super.onStop();
-        stopSearchTask();
+        if(subscription != null) {
+            subscription.unsubscribe();
+        }
         EventDistributor.getInstance().unregister(contentUpdate);
     }
 
     @Override
     public void onDetach() {
         super.onDetach();
-        stopSearchTask();
+        if(subscription != null) {
+            subscription.unsubscribe();
+        }
     }
 
     @Override
@@ -143,7 +152,7 @@ public class SearchFragment extends ListFragment {
                 public boolean onQueryTextSubmit(String s) {
                     getArguments().putString(ARG_QUERY, s);
                     itemsLoaded = false;
-                    startSearchTask();
+                    search();
                     return true;
                 }
 
@@ -161,7 +170,7 @@ public class SearchFragment extends ListFragment {
         public void update(EventDistributor eventDistributor, Integer arg) {
             if ((arg & (EventDistributor.UNREAD_ITEMS_UPDATE
                     | EventDistributor.DOWNLOAD_HANDLED)) != 0) {
-                startSearchTask();
+                search();
             }
         }
     };
@@ -187,53 +196,36 @@ public class SearchFragment extends ListFragment {
         }
     };
 
-    private SearchTask searchTask;
 
-    private void startSearchTask() {
-        if (searchTask != null) {
-            searchTask.cancel(true);
+    private void search() {
+        if(subscription != null) {
+            subscription.unsubscribe();
         }
-        searchTask = new SearchTask();
-        searchTask.execute(getArguments());
-    }
-
-    private void stopSearchTask() {
-        if (searchTask != null) {
-            searchTask.cancel(true);
+        if (viewCreated && !itemsLoaded) {
+            setListShown(false);
         }
+        subscription = Observable.defer(() -> Observable.just(performSearch()))
+                .subscribeOn(Schedulers.newThread())
+                .observeOn(AndroidSchedulers.mainThread())
+                .subscribe(result -> {
+                    if (result != null) {
+                        itemsLoaded = true;
+                        searchResults = result;
+                        if (viewCreated) {
+                            onFragmentLoaded();
+                        }
+                    }
+                }, error -> {
+                    Log.e(TAG, Log.getStackTraceString(error));
+                });
     }
 
-    private class SearchTask extends AsyncTask<Bundle, Void, List<SearchResult>> {
-        @Override
-        protected List<SearchResult> doInBackground(Bundle... params) {
-            String query = params[0].getString(ARG_QUERY);
-            long feed = params[0].getLong(ARG_FEED);
-            Context context = getActivity();
-            if (context != null) {
-                return FeedSearcher.performSearch(context, query, feed);
-            } else {
-                return Collections.emptyList();
-            }
-        }
-
-        @Override
-        protected void onPreExecute() {
-            super.onPreExecute();
-            if (viewCreated && !itemsLoaded) {
-                setListShown(false);
-            }
-        }
-
-        @Override
-        protected void onPostExecute(List<SearchResult> results) {
-            super.onPostExecute(results);
-            if (results != null) {
-                itemsLoaded = true;
-                searchResults = results;
-                if (viewCreated) {
-                    onFragmentLoaded();
-                }
-            }
-        }
+    private List<SearchResult> performSearch() {
+        Bundle args = getArguments();
+        String query = args.getString(ARG_QUERY);
+        long feed = args.getLong(ARG_FEED);
+        Context context = getActivity();
+        return FeedSearcher.performSearch(context, query, feed);
     }
+
 }