[Android] Manage audio lists loading with liveData

[Geoffrey Métais]

vlc-android | branch: master | Geoffrey Métais <geoffrey.metais at gmail.com> | Thu Sep 27 14:05:17 2018 +0200| [adcef71cf2cfabd3290e82a515fca9d4c97f0a42] | committer: Geoffrey Métais

Manage audio lists loading with liveData

> https://code.videolan.org/videolan/vlc-android/commit/adcef71cf2cfabd3290e82a515fca9d4c97f0a42
---

 .../vlc/gui/audio/AudioBrowserFragment.java        | 24 ++++++++++++----------
 .../videolan/vlc/viewmodels/paged/MLPagedModel.kt  | 11 +++++++---
 2 files changed, 21 insertions(+), 14 deletions(-)

diff --git a/vlc-android/src/org/videolan/vlc/gui/audio/AudioBrowserFragment.java b/vlc-android/src/org/videolan/vlc/gui/audio/AudioBrowserFragment.java
index fb8756db2..9ff38c71c 100644
--- a/vlc-android/src/org/videolan/vlc/gui/audio/AudioBrowserFragment.java
+++ b/vlc-android/src/org/videolan/vlc/gui/audio/AudioBrowserFragment.java
@@ -100,7 +100,7 @@ public class AudioBrowserFragment extends BaseAudioBrowser implements SwipeRefre
     public void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         if (mSettings == null) mSettings = Settings.INSTANCE.getInstance(requireContext());
-        setupAdapters(mSettings.getInt(Constants.KEY_AUDIO_CURRENT_TAB, 0));
+        setupModels();
     }
 
     @Override
@@ -145,7 +145,7 @@ public class AudioBrowserFragment extends BaseAudioBrowser implements SwipeRefre
         mSwipeRefreshLayout.setOnRefreshListener(this);
     }
 
-    private void setupAdapters(final int currentTab) {
+    private void setupModels() {
         if (mArtistsAdapter == null) {
             artistModel = ViewModelProviders.of(requireActivity(), new PagedArtistsModel.Factory(requireContext(), mSettings.getBoolean(Constants.KEY_ARTISTS_SHOW_ALL, false))).get(PagedArtistsModel.class);
             mArtistsAdapter = new AudioBrowserAdapter(MediaLibraryItem.TYPE_ARTIST, this, artistModel.getSort());
@@ -168,15 +168,7 @@ public class AudioBrowserFragment extends BaseAudioBrowser implements SwipeRefre
         }
         mAdapters = new AudioBrowserAdapter[] {mArtistsAdapter, mAlbumsAdapter, mSongsAdapter, mGenresAdapter, mPlaylistAdapter};
         models = new MLPagedModel[] {artistModel, albumModel, tracksModel, genresModel, playlistsModel};
-        //Register current tab first
-        models[currentTab].getPagedList().observe(this, new Observer<PagedList<MediaLibraryItem>>() {
-            @Override
-            public void onChanged(@Nullable PagedList<MediaLibraryItem> items) {
-                if (items != null) mAdapters[currentTab].submitList(items);
-            }
-        });
         for (int i = 0; i < models.length; ++i ) {
-            if (i == currentTab) continue;
             final int index = i;
             models[i].getPagedList().observe(this, new Observer<PagedList<MediaLibraryItem>>() {
                 @Override
@@ -184,6 +176,14 @@ public class AudioBrowserFragment extends BaseAudioBrowser implements SwipeRefre
                     if (items != null) mAdapters[index].submitList(items);
                 }
             });
+            models[i].getLoading().observe(this, new Observer<Boolean>() {
+                @Override
+                public void onChanged(@Nullable Boolean loading) {
+                    if (loading == null || mViewPager.getCurrentItem() != index) return;
+                    if (loading) mHandler.sendEmptyMessageDelayed(SET_REFRESHING, 300);
+                    else mHandler.sendEmptyMessage(UNSET_REFRESHING);
+                }
+            });
         }
     }
 
@@ -284,6 +284,9 @@ public class AudioBrowserFragment extends BaseAudioBrowser implements SwipeRefre
         requireActivity().invalidateOptionsMenu();
         mFastScroller.setRecyclerView(mLists[tab.getPosition()], getViewModel().getTotalCount());
         mSettings.edit().putInt(Constants.KEY_AUDIO_CURRENT_TAB, tab.getPosition()).apply();
+        final Boolean loading = getViewModel().getLoading().getValue();
+        if (loading == null || loading == false) mHandler.sendEmptyMessage(UNSET_REFRESHING);
+        else mHandler.sendEmptyMessage(SET_REFRESHING);
     }
 
     @Override
@@ -338,7 +341,6 @@ public class AudioBrowserFragment extends BaseAudioBrowser implements SwipeRefre
     public void onUpdateFinished(RecyclerView.Adapter adapter) {
         super.onUpdateFinished(adapter);
         if (adapter == getCurrentAdapter()) {
-            if (!mMediaLibrary.isWorking()) mHandler.sendEmptyMessage(UNSET_REFRESHING);
             mSwipeRefreshLayout.setEnabled(((LinearLayoutManager)getCurrentRV().getLayoutManager()).findFirstVisibleItemPosition() <= 0);
             updateEmptyView(mViewPager.getCurrentItem());
             mFastScroller.setRecyclerView(getCurrentRV(), getViewModel().getTotalCount());
diff --git a/vlc-android/src/org/videolan/vlc/viewmodels/paged/MLPagedModel.kt b/vlc-android/src/org/videolan/vlc/viewmodels/paged/MLPagedModel.kt
index ef9446f9f..de51b2f75 100644
--- a/vlc-android/src/org/videolan/vlc/viewmodels/paged/MLPagedModel.kt
+++ b/vlc-android/src/org/videolan/vlc/viewmodels/paged/MLPagedModel.kt
@@ -1,5 +1,6 @@
 package org.videolan.vlc.viewmodels.paged
 
+import android.arch.lifecycle.MutableLiveData
 import android.arch.paging.DataSource
 import android.arch.paging.LivePagedListBuilder
 import android.arch.paging.PagedList
@@ -13,6 +14,8 @@ import org.videolan.vlc.viewmodels.SortableModel
 abstract class MLPagedModel<T : MediaLibraryItem>(context: Context) : SortableModel(context), Medialibrary.OnMedialibraryReadyListener {
     protected val medialibrary = Medialibrary.getInstance()
     protected var filter : String? = null
+    val loading = MutableLiveData<Boolean>().apply { value = true }
+
     private val pagingConfig = PagedList.Config.Builder()
             .setPageSize(100)
             .setPrefetchDistance(100)
@@ -68,18 +71,20 @@ abstract class MLPagedModel<T : MediaLibraryItem>(context: Context) : SortableMo
     }
 
     override fun refresh(): Boolean {
+        loading.value = true
         pagedList.value?.dataSource?.invalidate()
         return true
     }
 
     inner class MLDataSource : PositionalDataSource<T>() {
-        override fun loadRange(params: LoadRangeParams, callback: LoadRangeCallback<T>) {
-            callback.onResult(getPage(params.loadSize, params.startPosition).toList())
-        }
 
         override fun loadInitial(params: LoadInitialParams, callback: LoadInitialCallback<T>) {
             val count = getTotalCount()
             callback.onResult(getPage(params.requestedLoadSize, params.requestedStartPosition).toList(), params.requestedStartPosition, count)
+            loading.postValue(false)
+        }
+        override fun loadRange(params: LoadRangeParams, callback: LoadRangeCallback<T>) {
+            callback.onResult(getPage(params.loadSize, params.startPosition).toList())
         }
     }