Add buttons to open next/previous chapter in the reader. Try entire app with hardware acceleration

app/src/main/AndroidManifest.xml

@@ -12,6 +12,7 @@
         android:allowBackup="true"
         android:icon="@mipmap/ic_launcher"
         android:label="@string/app_name"
+        android:hardwareAccelerated="true"
         android:theme="@style/AppTheme" >
         <activity
             android:name=".ui.main.MainActivity">
@@ -27,8 +28,7 @@
         </activity>
         <activity
             android:name=".ui.reader.ReaderActivity"
-            android:parentActivityName=".ui.manga.MangaActivity"
-            android:hardwareAccelerated="true">
+            android:parentActivityName=".ui.manga.MangaActivity">
             <meta-data
                 android:name="android.support.PARENT_ACTIVITY"
                 android:value=".ui.manga.MangaActivity" />

app/src/main/java/eu/kanade/mangafeed/ui/reader/ReaderActivity.java

@@ -9,6 +9,8 @@ import android.os.Bundle;
 import android.support.annotation.NonNull;
 import android.support.v4.content.ContextCompat;
 import android.support.v7.widget.Toolbar;
+import android.view.Menu;
+import android.view.MenuItem;
 import android.view.Surface;
 import android.view.View;
 import android.view.WindowManager;
@@ -111,6 +113,16 @@ public class ReaderActivity extends BaseRxActivity<ReaderPresenter> {
         super.onDestroy();
     }
 
+    @Override
+    public boolean onCreateOptionsMenu(Menu menu) {
+        return readerMenu.onCreateOptionsMenu(menu);
+    }
+
+    @Override
+    public boolean onOptionsItemSelected(MenuItem item) {
+        return readerMenu.onOptionsItemSelected(item) || super.onOptionsItemSelected(item);
+    }
+
     @Override
     protected void onSaveInstanceState(@NonNull Bundle outState) {
         Icepick.saveInstanceState(readerMenu, outState);
@@ -131,6 +143,10 @@ public class ReaderActivity extends BaseRxActivity<ReaderPresenter> {
         readerMenu.onChapterReady(pages.size(), manga, chapter, currentPage);
     }
 
+    public void onAdjacentChapters(Chapter previous, Chapter next) {
+        readerMenu.onAdjacentChapters(previous, next);
+    }
+
     private BaseReader createViewer(Manga manga) {
         int mangaViewer = manga.viewer == 0 ? preferences.getDefaultViewer() : manga.viewer;
 
@@ -160,6 +176,21 @@ public class ReaderActivity extends BaseRxActivity<ReaderPresenter> {
         readerMenu.toggle();
     }
 
+    public void requestNextChapter() {
+        getPresenter().setCurrentPage(viewer != null ? viewer.getCurrentPage() : 0);
+        if (!getPresenter().loadNextChapter()) {
+            ToastUtil.showShort(this, R.string.no_next_chapter);
+        }
+
+    }
+
+    public void requestPreviousChapter() {
+        getPresenter().setCurrentPage(viewer != null ? viewer.getCurrentPage() : 0);
+        if (!getPresenter().loadPreviousChapter()) {
+            ToastUtil.showShort(this, R.string.no_previous_chapter);
+        }
+    }
+
     private void initializeSettings() {
         subscriptions.add(preferences.showPageNumber()
                 .asObservable()

app/src/main/java/eu/kanade/mangafeed/ui/reader/ReaderMenu.java

@@ -5,6 +5,8 @@ import android.content.Context;
 import android.support.v7.app.AlertDialog;
 import android.support.v7.widget.Toolbar;
 import android.view.Gravity;
+import android.view.Menu;
+import android.view.MenuItem;
 import android.view.View;
 import android.view.WindowManager;
 import android.view.WindowManager.LayoutParams;
@@ -42,6 +44,11 @@ public class ReaderMenu {
     @Bind(R.id.reader_extra_settings) ImageButton extraSettings;
     @Bind(R.id.reader_brightness) ImageButton brightnessSettings;
 
+    private MenuItem nextChapterBtn;
+    private MenuItem prevChapterBtn;
+    private Chapter prevChapter;
+    private Chapter nextChapter;
+
     private ReaderActivity activity;
     private PreferencesHelper preferences;
 
@@ -106,6 +113,25 @@ public class ReaderMenu {
         showing = false;
     }
 
+    public boolean onCreateOptionsMenu(Menu menu) {
+        activity.getMenuInflater().inflate(R.menu.reader, menu);
+        nextChapterBtn = menu.findItem(R.id.action_next_chapter);
+        prevChapterBtn = menu.findItem(R.id.action_previous_chapter);
+        setAdjacentChaptersVisibility();
+        return true;
+    }
+
+    public boolean onOptionsItemSelected(MenuItem item) {
+        if (item == prevChapterBtn) {
+            activity.requestPreviousChapter();
+        } else if (item == nextChapterBtn) {
+            activity.requestNextChapter();
+        } else {
+            return false;
+        }
+        return true;
+    }
+
     public void onChapterReady(int numPages, Manga manga, Chapter chapter, int currentPageIndex) {
         if (manga.viewer == ReaderActivity.RIGHT_TO_LEFT && !inverted) {
             // Invert the seekbar and textview fields for the right to left reader
@@ -136,6 +162,17 @@ public class ReaderMenu {
         seekBar.setProgress(pageIndex);
     }
 
+    public void onAdjacentChapters(Chapter previous, Chapter next) {
+        prevChapter = previous;
+        nextChapter = next;
+        setAdjacentChaptersVisibility();
+    }
+
+    private void setAdjacentChaptersVisibility() {
+        if (prevChapterBtn != null) prevChapterBtn.setVisible(prevChapter != null);
+        if (nextChapterBtn != null) nextChapterBtn.setVisible(nextChapter != null);
+    }
+
     private void initializeOptions() {
         // Orientation changes
         add(preferences.lockOrientation().asObservable()

app/src/main/java/eu/kanade/mangafeed/ui/reader/ReaderPresenter.java

@@ -2,6 +2,7 @@ package eu.kanade.mangafeed.ui.reader;
 
 import android.os.Bundle;
 import android.support.annotation.NonNull;
+import android.util.Pair;
 
 import java.io.File;
 import java.util.List;
@@ -53,8 +54,9 @@ public class ReaderPresenter extends BasePresenter<ReaderActivity> {
 
     private static final int GET_PAGE_LIST = 1;
     private static final int GET_PAGE_IMAGES = 2;
-    private static final int RETRY_IMAGES = 3;
-    private static final int PRELOAD_NEXT_CHAPTER = 4;
+    private static final int GET_ADJACENT_CHAPTERS = 3;
+    private static final int RETRY_IMAGES = 4;
+    private static final int PRELOAD_NEXT_CHAPTER = 5;
 
     @Override
     protected void onCreate(Bundle savedState) {
@@ -71,12 +73,16 @@ public class ReaderPresenter extends BasePresenter<ReaderActivity> {
                 (view, pages) -> {},
                 (view, error) -> Timber.e("An error occurred while preloading a chapter"));
 
-        restartableReplay(GET_PAGE_IMAGES,
-                () -> getPageImagesObservable()
-                        .doOnCompleted(this::preloadNextChapter),
+        restartableLatestCache(GET_PAGE_IMAGES,
+                this::getPageImagesObservable,
                 (view, page) -> {},
                 (view, error) -> Timber.e("An error occurred while downloading an image"));
 
+        restartableLatestCache(GET_ADJACENT_CHAPTERS,
+                this::getAdjacentChaptersObservable,
+                (view, pair) -> view.onAdjacentChapters(pair.first, pair.second),
+                (view, error) -> Timber.e("An error occurred while getting adjacent chapters"));
+
         restartableLatestCache(RETRY_IMAGES,
                 this::getRetryPageObservable,
                 (view, page) -> {},
@@ -86,7 +92,7 @@ public class ReaderPresenter extends BasePresenter<ReaderActivity> {
                 () -> getPageListObservable()
                         .doOnNext(pages -> pageList = pages)
                         .doOnCompleted(() -> {
-                            getAdjacentChapters();
+                            start(GET_ADJACENT_CHAPTERS);
                             start(GET_PAGE_IMAGES);
                             start(RETRY_IMAGES);
                         }),
@@ -117,6 +123,7 @@ public class ReaderPresenter extends BasePresenter<ReaderActivity> {
 
         // These are started by GET_PAGE_LIST, so we don't let them restart itselves
         stop(GET_PAGE_IMAGES);
+        stop(GET_ADJACENT_CHAPTERS);
         stop(RETRY_IMAGES);
         stop(PRELOAD_NEXT_CHAPTER);
     }
@@ -153,9 +160,19 @@ public class ReaderPresenter extends BasePresenter<ReaderActivity> {
             pageObservable = Observable.from(pageList)
                     .flatMap(page -> downloadManager.getDownloadedImage(page, chapterDir));
         }
-        return Observable.defer(() -> pageObservable)
-                .subscribeOn(Schedulers.io())
-                .onBackpressureBuffer()
+        return pageObservable.subscribeOn(Schedulers.io())
+                .doOnCompleted(this::preloadNextChapter);
+    }
+
+    private Observable<Pair<Chapter, Chapter>> getAdjacentChaptersObservable() {
+        return Observable.zip(
+                db.getPreviousChapter(chapter).createObservable().take(1),
+                db.getNextChapter(chapter).createObservable().take(1),
+                Pair::create)
+                .doOnNext(pair -> {
+                    previousChapter = pair.first;
+                    nextChapter = pair.second;
+                })
                 .observeOn(AndroidSchedulers.mainThread());
     }
 
@@ -275,28 +292,22 @@ public class ReaderPresenter extends BasePresenter<ReaderActivity> {
         this.currentPage = currentPage;
     }
 
-    private void getAdjacentChapters() {
-        add(db.getNextChapter(chapter).createObservable()
-                .take(1)
-                .subscribe(result -> nextChapter = result));
-
-        add(db.getPreviousChapter(chapter).createObservable()
-                .take(1)
-                .subscribe(result -> previousChapter = result));
-    }
-
-    public void loadNextChapter() {
+    public boolean loadNextChapter() {
         if (hasNextChapter()) {
             onChapterLeft();
             loadChapter(nextChapter);
+            return true;
         }
+        return false;
     }
 
-    public void loadPreviousChapter() {
+    public boolean loadPreviousChapter() {
         if (hasPreviousChapter()) {
             onChapterLeft();
             loadChapter(previousChapter);
+            return true;
         }
+        return false;
     }
 
     public boolean hasNextChapter() {

app/src/main/java/eu/kanade/mangafeed/ui/reader/viewer/base/BaseReader.java

@@ -4,12 +4,9 @@ import android.view.MotionEvent;
 
 import java.util.List;
 
-import eu.kanade.mangafeed.R;
 import eu.kanade.mangafeed.data.source.model.Page;
 import eu.kanade.mangafeed.ui.base.fragment.BaseFragment;
 import eu.kanade.mangafeed.ui.reader.ReaderActivity;
-import eu.kanade.mangafeed.ui.reader.ReaderPresenter;
-import eu.kanade.mangafeed.util.ToastUtil;
 
 public abstract class BaseReader extends BaseFragment {
 
@@ -32,27 +29,6 @@ public abstract class BaseReader extends BaseFragment {
         return page;
     }
 
-    public void requestNextChapter() {
-        ReaderPresenter presenter = getReaderActivity().getPresenter();
-        if (presenter.hasNextChapter()) {
-            presenter.setCurrentPage(getCurrentPage());
-            presenter.loadNextChapter();
-        } else {
-            ToastUtil.showShort(getActivity(), R.string.no_next_chapter);
-        }
-
-    }
-
-    public void requestPreviousChapter() {
-        ReaderPresenter presenter = getReaderActivity().getPresenter();
-        if (presenter.hasPreviousChapter()) {
-            presenter.setCurrentPage(getCurrentPage());
-            presenter.loadPreviousChapter();
-        } else {
-            ToastUtil.showShort(getActivity(), R.string.no_previous_chapter);
-        }
-    }
-
     public void onPageChanged(int position) {
         currentPage = getPageForPosition(position);
         updatePageNumber();

app/src/main/java/eu/kanade/mangafeed/ui/reader/viewer/common/PagerReader.java

@@ -70,12 +70,14 @@ public abstract class PagerReader extends BaseReader {
 
     @Override
     public void onPageListReady(List<Page> pages, int currentPage) {
+        if (this.pages != pages) {
             this.pages = pages;
             this.currentPage = currentPage;
             if (isResumed()) {
                 setPages();
             }
         }
+    }
 
     protected void setPages() {
         if (pages != null) {

app/src/main/java/eu/kanade/mangafeed/ui/reader/viewer/horizontal/LeftToRightReader.java

@@ -4,12 +4,12 @@ public class LeftToRightReader extends HorizontalReader {
 
     @Override
     public void onFirstPageOut() {
-        requestPreviousChapter();
+        getReaderActivity().requestPreviousChapter();
     }
 
     @Override
     public void onLastPageOut() {
-        requestNextChapter();
+        getReaderActivity().requestNextChapter();
     }
 
 }

app/src/main/java/eu/kanade/mangafeed/ui/reader/viewer/horizontal/RightToLeftReader.java

@@ -27,12 +27,12 @@ public class RightToLeftReader extends HorizontalReader {
 
     @Override
     public void onFirstPageOut() {
-        requestNextChapter();
+        getReaderActivity().requestNextChapter();
     }
 
     @Override
     public void onLastPageOut() {
-        requestPreviousChapter();
+        getReaderActivity().requestPreviousChapter();
     }
 
 }

app/src/main/java/eu/kanade/mangafeed/ui/reader/viewer/vertical/VerticalReader.java

@@ -18,12 +18,12 @@ public class VerticalReader extends PagerReader {
 
     @Override
     public void onFirstPageOut() {
-        requestPreviousChapter();
+        getReaderActivity().requestPreviousChapter();
     }
 
     @Override
     public void onLastPageOut() {
-        requestNextChapter();
+        getReaderActivity().requestNextChapter();
     }
 
 }

app/src/main/java/eu/kanade/mangafeed/ui/reader/viewer/webtoon/WebtoonAdapter.java

@@ -58,6 +58,13 @@ public class WebtoonAdapter extends RecyclerView.Adapter<WebtoonAdapter.ImageHol
         notifyItemInserted(page.getPageNumber());
     }
 
+    public void clear() {
+        if (pages != null) {
+            pages.clear();
+            notifyDataSetChanged();
+        }
+    }
+
     public static class ImageHolder extends RecyclerView.ViewHolder {
 
         @Bind(R.id.page_image_view) SubsamplingScaleImageView imageView;

app/src/main/java/eu/kanade/mangafeed/ui/reader/viewer/webtoon/WebtoonReader.java

@@ -73,9 +73,13 @@ public class WebtoonReader extends BaseReader {
 
     @Override
     public void onPause() {
+        unsubscribeStatus();
+        super.onPause();
+    }
+
+    private void unsubscribeStatus() {
         if (subscription != null && !subscription.isUnsubscribed())
             subscription.unsubscribe();
-        super.onPause();
     }
 
     @Override
@@ -85,14 +89,18 @@ public class WebtoonReader extends BaseReader {
 
     @Override
     public void onPageListReady(List<Page> pages, int currentPage) {
+        if (this.pages != pages) {
             this.pages = pages;
             if (isResumed()) {
                 setPages();
             }
         }
+    }
 
     private void setPages() {
         if (pages != null) {
+            unsubscribeStatus();
+            adapter.clear();
             observeStatus(0);
         }
     }
@@ -112,8 +120,8 @@ public class WebtoonReader extends BaseReader {
         PublishSubject<Integer> statusSubject = PublishSubject.create();
         page.setStatusSubject(statusSubject);
 
-        if (subscription != null && !subscription.isUnsubscribed())
-            subscription.unsubscribe();
+        // Unsubscribe from the previous page
+        unsubscribeStatus();
 
         subscription = statusSubject
                 .startWith(page.getStatus())

app/src/main/res/anim/fade_in.xml

@@ -4,5 +4,6 @@
         android:fromAlpha="0.0"
         android:toAlpha="1.0"
         android:interpolator="@android:anim/accelerate_interpolator"
-        android:duration="300" />
+        android:duration="300"
+        android:fillAfter="true"/>
 </set>

app/src/main/res/menu/reader.xml

@@ -0,0 +1,19 @@
+<?xml version="1.0" encoding="utf-8"?>
+<menu xmlns:android="http://schemas.android.com/apk/res/android"
+      xmlns:app="http://schemas.android.com/apk/res-auto">
+
+    <item
+        android:id="@+id/action_previous_chapter"
+        android:title="@string/action_previous_chapter"
+        android:icon="@drawable/ic_skip_previous_white_24dp"
+        android:visible="false"
+        app:showAsAction="always" />
+
+    <item
+        android:id="@+id/action_next_chapter"
+        android:title="@string/action_next_chapter"
+        android:icon="@drawable/ic_skip_next_white_24dp"
+        android:visible="false"
+        app:showAsAction="always" />
+
+</menu>

app/src/main/res/values/strings.xml

@@ -34,6 +34,9 @@
     <string name="action_next_unread">Next unread</string>
     <string name="action_start">Start</string>
     <string name="action_stop">Stop</string>
+    <string name="action_previous_chapter">Previous chapter</string>
+    <string name="action_next_chapter">Next chapter</string>
+
 
     <!-- Buttons -->
     <string name="button_ok">OK</string>