Add TrackSelectionDialog (with swipe tabs) to demo app.

PiperOrigin-RevId: 233582549

demos/main/build.gradle

@@ -63,6 +63,9 @@ android {
 
 dependencies {
     implementation 'com.android.support:support-annotations:' + supportLibraryVersion
+    implementation 'com.android.support:support-core-ui:' + supportLibraryVersion
+    implementation 'com.android.support:support-fragment:' + supportLibraryVersion
+    implementation 'com.android.support:design:' + supportLibraryVersion
     implementation project(modulePrefix + 'library-core')
     implementation project(modulePrefix + 'library-dash')
     implementation project(modulePrefix + 'library-hls')

demos/main/src/main/AndroidManifest.xml

@@ -39,7 +39,8 @@
 
     <activity android:name="com.google.android.exoplayer2.demo.SampleChooserActivity"
         android:configChanges="keyboardHidden"
-        android:label="@string/application_name">
+        android:label="@string/application_name"
+        android:theme="@style/Theme.AppCompat">
       <intent-filter>
         <action android:name="android.intent.action.MAIN"/>
         <category android:name="android.intent.category.LAUNCHER"/>

demos/main/src/main/java/com/google/android/exoplayer2/demo/DownloadTracker.java

@@ -15,20 +15,12 @@
  */
 package com.google.android.exoplayer2.demo;
 
-import android.app.Activity;
-import android.app.AlertDialog;
 import android.content.Context;
 import android.content.DialogInterface;
-import android.content.res.Resources;
 import android.net.Uri;
 import android.os.Handler;
 import android.os.HandlerThread;
-import android.support.annotation.Nullable;
-import android.view.LayoutInflater;
-import android.view.View;
-import android.widget.ImageButton;
-import android.widget.LinearLayout;
-import android.widget.TextView;
+import android.support.v4.app.FragmentManager;
 import android.widget.Toast;
 import com.google.android.exoplayer2.C;
 import com.google.android.exoplayer2.RenderersFactory;
@@ -46,11 +38,6 @@ import com.google.android.exoplayer2.source.TrackGroupArray;
 import com.google.android.exoplayer2.trackselection.DefaultTrackSelector;
 import com.google.android.exoplayer2.trackselection.DefaultTrackSelector.SelectionOverride;
 import com.google.android.exoplayer2.trackselection.MappingTrackSelector.MappedTrackInfo;
-import com.google.android.exoplayer2.trackselection.TrackSelection;
-import com.google.android.exoplayer2.trackselection.TrackSelectionUtil;
-import com.google.android.exoplayer2.ui.DefaultTrackNameProvider;
-import com.google.android.exoplayer2.ui.TrackNameProvider;
-import com.google.android.exoplayer2.ui.TrackSelectionDialogBuilder;
 import com.google.android.exoplayer2.upstream.DataSource;
 import com.google.android.exoplayer2.util.Log;
 import com.google.android.exoplayer2.util.Util;
@@ -81,7 +68,6 @@ public class DownloadTracker implements DownloadManager.Listener {
 
   private final Context context;
   private final DataSource.Factory dataSourceFactory;
-  private final TrackNameProvider trackNameProvider;
   private final CopyOnWriteArraySet<Listener> listeners;
   private final HashMap<Uri, DownloadState> trackedDownloadStates;
   private final DefaultDownloadIndex downloadIndex;
@@ -92,7 +78,6 @@ public class DownloadTracker implements DownloadManager.Listener {
     this.context = context.getApplicationContext();
     this.dataSourceFactory = dataSourceFactory;
     this.downloadIndex = downloadIndex;
-    trackNameProvider = new DefaultTrackNameProvider(context.getResources());
     listeners = new CopyOnWriteArraySet<>();
     trackedDownloadStates = new HashMap<>();
     HandlerThread actionFileWriteThread = new HandlerThread("DownloadTracker");
@@ -122,7 +107,7 @@ public class DownloadTracker implements DownloadManager.Listener {
   }
 
   public void toggleDownload(
-      Activity activity,
+      FragmentManager fragmentManager,
       String name,
       Uri uri,
       String extension,
@@ -133,7 +118,7 @@ public class DownloadTracker implements DownloadManager.Listener {
       startServiceWithAction(removeAction);
     } else {
       new StartDownloadDialogHelper(
-          activity, getDownloadHelper(uri, extension, renderersFactory), name);
+          fragmentManager, getDownloadHelper(uri, extension, renderersFactory), name);
     }
   }
 
@@ -225,42 +210,23 @@ public class DownloadTracker implements DownloadManager.Listener {
     }
   }
 
-  @SuppressWarnings("UngroupedOverloads")
   private final class StartDownloadDialogHelper
       implements DownloadHelper.Callback,
           DialogInterface.OnClickListener,
-          DialogInterface.OnDismissListener,
-          View.OnClickListener {
+          DialogInterface.OnDismissListener {
 
+    private final FragmentManager fragmentManager;
     private final DownloadHelper downloadHelper;
     private final String name;
-    private final LayoutInflater dialogInflater;
-    private final AlertDialog dialog;
-    private final LinearLayout selectionList;
 
+    private TrackSelectionDialog trackSelectionDialog;
     private MappedTrackInfo mappedTrackInfo;
-    private DefaultTrackSelector.Parameters parameters;
 
-    private StartDownloadDialogHelper(
-        Activity activity, DownloadHelper downloadHelper, String name) {
+    public StartDownloadDialogHelper(
+        FragmentManager fragmentManager, DownloadHelper downloadHelper, String name) {
+      this.fragmentManager = fragmentManager;
       this.downloadHelper = downloadHelper;
       this.name = name;
-      AlertDialog.Builder builder =
-          new AlertDialog.Builder(activity)
-              .setTitle(R.string.download_preparing)
-              .setPositiveButton(android.R.string.ok, /* listener= */ this)
-              .setNegativeButton(android.R.string.cancel, /* listener= */ null);
-
-      // Inflate with the builder's context to ensure the correct style is used.
-      dialogInflater = LayoutInflater.from(builder.getContext());
-      selectionList = (LinearLayout) dialogInflater.inflate(R.layout.start_download_dialog, null);
-      builder.setView(selectionList);
-      dialog = builder.create();
-      dialog.setOnDismissListener(/* listener= */ this);
-      dialog.show();
-      dialog.getButton(AlertDialog.BUTTON_POSITIVE).setEnabled(false);
-
-      parameters = DownloadHelper.DEFAULT_TRACK_SELECTOR_PARAMETERS;
       downloadHelper.prepare(this);
     }
 
@@ -268,12 +234,19 @@ public class DownloadTracker implements DownloadManager.Listener {
 
     @Override
     public void onPrepared(DownloadHelper helper) {
-      if (helper.getPeriodCount() > 0) {
-        mappedTrackInfo = downloadHelper.getMappedTrackInfo(/* periodIndex= */ 0);
-        updateSelectionList();
+      if (helper.getPeriodCount() == 0) {
+        onPrepareError(helper, new IOException("No periods found."));
+        return;
       }
-      dialog.setTitle(R.string.exo_download_description);
-      dialog.getButton(AlertDialog.BUTTON_POSITIVE).setEnabled(true);
+      mappedTrackInfo = downloadHelper.getMappedTrackInfo(/* periodIndex= */ 0);
+      trackSelectionDialog = new TrackSelectionDialog();
+      trackSelectionDialog.init(
+          mappedTrackInfo,
+          /* allowAdaptiveSelections =*/ false,
+          /* allowMultipleOverrides= */ true,
+          /* onClickListener= */ this,
+          /* onDismissListener= */ this);
+      trackSelectionDialog.show(fragmentManager, "download");
     }
 
     @Override
@@ -282,33 +255,44 @@ public class DownloadTracker implements DownloadManager.Listener {
               context.getApplicationContext(), R.string.download_start_error, Toast.LENGTH_LONG)
           .show();
       Log.e(TAG, "Failed to start download", e);
-      dialog.cancel();
-    }
-
-    // View.OnClickListener implementation.
-
-    @Override
-    public void onClick(View v) {
-      Integer rendererIndex = (Integer) v.getTag();
-      TrackGroupArray trackGroupArray = mappedTrackInfo.getTrackGroups(rendererIndex);
-      String dialogTitle = getTrackTypeString(mappedTrackInfo.getRendererType(rendererIndex));
-      new TrackSelectionDialogBuilder(
-              dialog.getContext(),
-              dialogTitle,
-              mappedTrackInfo,
-              rendererIndex,
-              (isDisabled, overrides) -> updateTracks(rendererIndex, isDisabled, overrides))
-          .setShowDisableOption(true)
-          .setIsDisabled(parameters.getRendererDisabled(rendererIndex))
-          .setOverride(parameters.getSelectionOverride(rendererIndex, trackGroupArray))
-          .build()
-          .show();
     }
 
     // DialogInterface.OnClickListener implementation.
 
     @Override
     public void onClick(DialogInterface dialog, int which) {
+      DefaultTrackSelector.ParametersBuilder builder =
+          DownloadHelper.DEFAULT_TRACK_SELECTOR_PARAMETERS.buildUpon();
+      for (int i = 0; i < mappedTrackInfo.getRendererCount(); i++) {
+        builder.setRendererDisabled(/* rendererIndex= */ i, /* disabled= */ true);
+      }
+      for (int i = 0; i < downloadHelper.getPeriodCount(); i++) {
+        downloadHelper.clearTrackSelections(/* periodIndex = */ i);
+      }
+      for (int i = 0; i < mappedTrackInfo.getRendererCount(); i++) {
+        if (trackSelectionDialog.getIsDisabled(/* rendererIndex= */ i)) {
+          continue;
+        }
+        builder.setRendererDisabled(/* rendererIndex= */ i, /* disabled= */ false);
+        List<SelectionOverride> overrides =
+            trackSelectionDialog.getOverrides(/* rendererIndex= */ i);
+        if (overrides.isEmpty()) {
+          for (int j = 0; j < downloadHelper.getPeriodCount(); j++) {
+            downloadHelper.addTrackSelection(/* periodIndex = */ j, builder.build());
+          }
+        } else {
+          TrackGroupArray trackGroupArray = mappedTrackInfo.getTrackGroups(/* rendererIndex= */ i);
+          for (int overrideIndex = 0; overrideIndex < overrides.size(); overrideIndex++) {
+            builder.setSelectionOverride(
+                /* rendererIndex= */ i, trackGroupArray, overrides.get(overrideIndex));
+            for (int j = 0; j < downloadHelper.getPeriodCount(); j++) {
+              downloadHelper.addTrackSelection(/* periodIndex = */ j, builder.build());
+            }
+          }
+          builder.clearSelectionOverrides();
+        }
+        builder.setRendererDisabled(/* rendererIndex= */ i, /* disabled= */ true);
+      }
       DownloadAction downloadAction = downloadHelper.getDownloadAction(Util.getUtf8Bytes(name));
       startDownload(downloadAction);
     }
@@ -316,86 +300,8 @@ public class DownloadTracker implements DownloadManager.Listener {
     // DialogInterface.OnDismissListener implementation.
 
     @Override
-    public void onDismiss(DialogInterface dialog) {
+    public void onDismiss(DialogInterface dialogInterface) {
       downloadHelper.release();
     }
-
-    // Internal methods.
-
-    private void updateTracks(
-        int rendererIndex, boolean isDisabled, List<SelectionOverride> overrides) {
-      parameters =
-          TrackSelectionUtil.updateParametersWithOverride(
-              parameters,
-              rendererIndex,
-              mappedTrackInfo.getTrackGroups(rendererIndex),
-              isDisabled,
-              overrides.isEmpty() ? null : overrides.get(0));
-      for (int i = 0; i < downloadHelper.getPeriodCount(); i++) {
-        downloadHelper.replaceTrackSelections(/* periodIndex= */ i, parameters);
-      }
-      updateSelectionList();
-    }
-
-    private void updateSelectionList() {
-      selectionList.removeAllViews();
-      for (int i = 0; i < mappedTrackInfo.getRendererCount(); i++) {
-        TrackGroupArray trackGroupArray = mappedTrackInfo.getTrackGroups(i);
-        if (trackGroupArray.length == 0) {
-          continue;
-        }
-        String trackTypeString =
-            getTrackTypeString(mappedTrackInfo.getRendererType(/* rendererIndex= */ i));
-        if (trackTypeString == null) {
-          return;
-        }
-        String trackSelectionsString = getTrackSelectionString(/* rendererIndex= */ i);
-        View view = dialogInflater.inflate(R.layout.download_track_item, selectionList, false);
-        TextView trackTitleView = view.findViewById(R.id.track_title);
-        TextView trackDescView = view.findViewById(R.id.track_desc);
-        ImageButton editButton = view.findViewById(R.id.edit_button);
-        trackTitleView.setText(trackTypeString);
-        trackDescView.setText(trackSelectionsString);
-        editButton.setTag(i);
-        editButton.setOnClickListener(this);
-        selectionList.addView(view);
-      }
-    }
-
-    private String getTrackSelectionString(int rendererIndex) {
-      List<TrackSelection> trackSelections =
-          downloadHelper.getTrackSelections(/* periodIndex= */ 0, rendererIndex);
-      String selectedTracks = "";
-      Resources resources = selectionList.getResources();
-      for (int i = 0; i < trackSelections.size(); i++) {
-        TrackSelection selection = trackSelections.get(i);
-        for (int j = 0; j < selection.length(); j++) {
-          String trackName = trackNameProvider.getTrackName(selection.getFormat(j));
-          if (i == 0 && j == 0) {
-            selectedTracks = trackName;
-          } else {
-            selectedTracks = resources.getString(R.string.exo_item_list, selectedTracks, trackName);
-          }
-        }
-      }
-      return selectedTracks.isEmpty()
-          ? resources.getString(R.string.exo_track_selection_none)
-          : selectedTracks;
-    }
-
-    @Nullable
-    private String getTrackTypeString(int trackType) {
-      Resources resources = selectionList.getResources();
-      switch (trackType) {
-        case C.TRACK_TYPE_VIDEO:
-          return resources.getString(R.string.exo_track_selection_title_video);
-        case C.TRACK_TYPE_AUDIO:
-          return resources.getString(R.string.exo_track_selection_title_audio);
-        case C.TRACK_TYPE_TEXT:
-          return resources.getString(R.string.exo_track_selection_title_text);
-        default:
-          return null;
-      }
-    }
   }
 }

demos/main/src/main/java/com/google/android/exoplayer2/demo/SampleChooserActivity.java

@@ -15,7 +15,6 @@
  */
 package com.google.android.exoplayer2.demo;
 
-import android.app.Activity;
 import android.content.Context;
 import android.content.Intent;
 import android.content.res.AssetManager;
@@ -23,6 +22,7 @@ import android.net.Uri;
 import android.os.AsyncTask;
 import android.os.Bundle;
 import android.support.annotation.Nullable;
+import android.support.v7.app.AppCompatActivity;
 import android.util.JsonReader;
 import android.view.Menu;
 import android.view.MenuInflater;
@@ -55,7 +55,7 @@ import java.util.Collections;
 import java.util.List;
 
 /** An activity for selecting from a list of media samples. */
-public class SampleChooserActivity extends Activity
+public class SampleChooserActivity extends AppCompatActivity
     implements DownloadTracker.Listener, OnChildClickListener {
 
   private static final String TAG = "SampleChooserActivity";
@@ -182,7 +182,11 @@ public class SampleChooserActivity extends Activity
           ((DemoApplication) getApplication())
               .buildRenderersFactory(isNonNullAndChecked(preferExtensionDecodersMenuItem));
       downloadTracker.toggleDownload(
-          this, sample.name, uriSample.uri, uriSample.extension, renderersFactory);
+          getSupportFragmentManager(),
+          sample.name,
+          uriSample.uri,
+          uriSample.extension,
+          renderersFactory);
     }
   }
 

demos/main/src/main/java/com/google/android/exoplayer2/demo/TrackSelectionDialog.java

@@ -0,0 +1,235 @@
+/*
+ * Copyright (C) 2019 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.google.android.exoplayer2.demo;
+
+import android.app.AlertDialog;
+import android.app.Dialog;
+import android.content.DialogInterface;
+import android.content.res.Resources;
+import android.os.Bundle;
+import android.support.annotation.Nullable;
+import android.support.design.widget.TabLayout;
+import android.support.v4.app.DialogFragment;
+import android.support.v4.app.Fragment;
+import android.support.v4.app.FragmentManager;
+import android.support.v4.app.FragmentPagerAdapter;
+import android.support.v4.view.ViewPager;
+import android.util.SparseArray;
+import android.view.LayoutInflater;
+import android.view.View;
+import android.view.ViewGroup;
+import com.google.android.exoplayer2.C;
+import com.google.android.exoplayer2.source.TrackGroupArray;
+import com.google.android.exoplayer2.trackselection.DefaultTrackSelector.SelectionOverride;
+import com.google.android.exoplayer2.trackselection.MappingTrackSelector.MappedTrackInfo;
+import com.google.android.exoplayer2.ui.TrackSelectionView;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+
+/** Dialog to select tracks. */
+public final class TrackSelectionDialog extends DialogFragment {
+
+  private final SparseArray<TrackSelectionViewFragment> tabFragments;
+  private final List<CharSequence> tabTitles;
+
+  private MappedTrackInfo mappedTrackInfo;
+  private boolean allowAdaptiveSelections;
+  private boolean allowMultipleOverrides;
+  private DialogInterface.OnClickListener onClickListener;
+  private DialogInterface.OnDismissListener onDismissListener;
+
+  /** Creates the dialog. */
+  public TrackSelectionDialog() {
+    tabFragments = new SparseArray<>();
+    tabTitles = new ArrayList<>();
+    // Retain instance across orientation changes to prevent loosing access to init data.
+    setRetainInstance(true);
+  }
+
+  /**
+   * Initializes the dialog.
+   *
+   * @param mappedTrackInfo The {@link MappedTrackInfo} to display.
+   * @param allowAdaptiveSelections Whether adaptive selections (consisting of more than one track)
+   *     can be made.
+   * @param allowMultipleOverrides Whether tracks from multiple track groups can be selected.
+   * @param onClickListener {@link DialogInterface.OnClickListener} called when tracks are selected.
+   * @param onDismissListener {@link DialogInterface.OnDismissListener} called when the dialog is
+   *     dismissed.
+   */
+  public void init(
+      MappedTrackInfo mappedTrackInfo,
+      boolean allowAdaptiveSelections,
+      boolean allowMultipleOverrides,
+      DialogInterface.OnClickListener onClickListener,
+      DialogInterface.OnDismissListener onDismissListener) {
+    this.mappedTrackInfo = mappedTrackInfo;
+    this.allowAdaptiveSelections = allowAdaptiveSelections;
+    this.allowMultipleOverrides = allowMultipleOverrides;
+    this.onClickListener = onClickListener;
+    this.onDismissListener = onDismissListener;
+  }
+
+  /**
+   * Returns whether a renderer is disabled.
+   *
+   * @param rendererIndex Renderer index.
+   * @return Whether the renderer is disabled.
+   */
+  public boolean getIsDisabled(int rendererIndex) {
+    TrackSelectionViewFragment rendererView = tabFragments.get(rendererIndex);
+    return rendererView != null && rendererView.trackSelectionView.getIsDisabled();
+  }
+
+  /**
+   * Returns the list of selected track selection overrides for the specified renderer. There will
+   * be at most one override for each track group.
+   *
+   * @param rendererIndex Renderer index.
+   * @return The list of track selection overrides for this renderer.
+   */
+  public List<SelectionOverride> getOverrides(int rendererIndex) {
+    TrackSelectionViewFragment rendererView = tabFragments.get(rendererIndex);
+    return rendererView == null
+        ? Collections.emptyList()
+        : rendererView.trackSelectionView.getOverrides();
+  }
+
+  @Override
+  public Dialog onCreateDialog(Bundle savedInstanceState) {
+    return new AlertDialog.Builder(getActivity())
+        .setTitle(R.string.exo_download_description)
+        .setPositiveButton(android.R.string.ok, onClickListener)
+        .setNegativeButton(android.R.string.cancel, /* listener= */ null)
+        .create();
+  }
+
+  @Override
+  public void onDismiss(DialogInterface dialog) {
+    super.onDismiss(dialog);
+    onDismissListener.onDismiss(dialog);
+  }
+
+  @Nullable
+  @Override
+  public View onCreateView(
+      LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
+    for (int i = 0; i < mappedTrackInfo.getRendererCount(); i++) {
+      TrackGroupArray trackGroupArray = mappedTrackInfo.getTrackGroups(i);
+      if (trackGroupArray.length == 0) {
+        continue;
+      }
+      String trackTypeString =
+          getTrackTypeString(mappedTrackInfo.getRendererType(/* rendererIndex= */ i));
+      if (trackTypeString == null) {
+        continue;
+      }
+      TrackSelectionViewFragment tabFragment = new TrackSelectionViewFragment();
+      tabFragment.init(
+          mappedTrackInfo, /* rendererIndex= */ i, allowAdaptiveSelections, allowMultipleOverrides);
+      tabFragments.put(i, tabFragment);
+      tabTitles.add(trackTypeString);
+    }
+    View dialogView = inflater.inflate(R.layout.download_dialog, container, false);
+    TabLayout tabLayout = dialogView.findViewById(R.id.download_dialog_tab_layout);
+    ViewPager viewPager = dialogView.findViewById(R.id.download_dialog_view_pager);
+    viewPager.setAdapter(new FragmentAdapter(getChildFragmentManager()));
+    tabLayout.setupWithViewPager(viewPager);
+    ((AlertDialog) getDialog()).setView(dialogView);
+    return dialogView;
+  }
+
+  @Nullable
+  private String getTrackTypeString(int trackType) {
+    Resources resources = getResources();
+    switch (trackType) {
+      case C.TRACK_TYPE_VIDEO:
+        return resources.getString(R.string.exo_track_selection_title_video);
+      case C.TRACK_TYPE_AUDIO:
+        return resources.getString(R.string.exo_track_selection_title_audio);
+      case C.TRACK_TYPE_TEXT:
+        return resources.getString(R.string.exo_track_selection_title_text);
+      default:
+        return null;
+    }
+  }
+
+  private final class FragmentAdapter extends FragmentPagerAdapter {
+
+    public FragmentAdapter(FragmentManager fragmentManager) {
+      super(fragmentManager);
+    }
+
+    @Override
+    public Fragment getItem(int position) {
+      return tabFragments.valueAt(position);
+    }
+
+    @Override
+    public int getCount() {
+      return tabFragments.size();
+    }
+
+    @Nullable
+    @Override
+    public CharSequence getPageTitle(int position) {
+      return tabTitles.get(position);
+    }
+  }
+
+  /** Fragment to show a track seleciton in tab of the track selection dialog. */
+  public static final class TrackSelectionViewFragment extends Fragment {
+
+    private MappedTrackInfo mappedTrackInfo;
+    private int rendererIndex;
+    private boolean allowAdaptiveSelections;
+    private boolean allowMultipleOverrides;
+
+    /* package */ TrackSelectionView trackSelectionView;
+
+    public void init(
+        MappedTrackInfo mappedTrackInfo,
+        int rendererIndex,
+        boolean allowAdaptiveSelections,
+        boolean allowMultipleOverrides) {
+      this.mappedTrackInfo = mappedTrackInfo;
+      this.rendererIndex = rendererIndex;
+      this.allowAdaptiveSelections = allowAdaptiveSelections;
+      this.allowMultipleOverrides = allowMultipleOverrides;
+    }
+
+    @Nullable
+    @Override
+    public View onCreateView(
+        LayoutInflater inflater,
+        @Nullable ViewGroup container,
+        @Nullable Bundle savedInstanceState) {
+      View rootView =
+          inflater.inflate(R.layout.download_dialog_tab, container, /* attachToRoot= */ false);
+      trackSelectionView = rootView.findViewById(R.id.download_dialog_track_selection_view);
+      trackSelectionView.setShowDisableOption(true);
+      trackSelectionView.setAllowMultipleOverrides(allowMultipleOverrides);
+      trackSelectionView.setAllowAdaptiveSelections(allowAdaptiveSelections);
+      trackSelectionView.init(
+          mappedTrackInfo,
+          rendererIndex,
+          /* isDisabled= */ false,
+          /* overrides= */ Collections.emptyList());
+      return rootView;
+    }
+  }
+}

demos/main/src/main/res/layout/download_dialog.xml

@@ -14,7 +14,15 @@
      limitations under the License.
 -->
 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
-    android:id="@+id/selection_list"
     android:orientation="vertical"
     android:layout_width="match_parent"
-    android:layout_height="match_parent"/>
+    android:layout_height="wrap_content">
+  <android.support.design.widget.TabLayout
+      android:id="@+id/download_dialog_tab_layout"
+      android:layout_width="match_parent"
+      android:layout_height="wrap_content"/>
+  <android.support.v4.view.ViewPager
+      android:id="@+id/download_dialog_view_pager"
+      android:layout_width="match_parent"
+      android:layout_height="wrap_content"/>
+</LinearLayout>

demos/main/src/main/res/layout/download_dialog_tab.xml

@@ -0,0 +1,24 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (C) 2018 The Android Open Source Project
+
+     Licensed under the Apache License, Version 2.0 (the "License");
+     you may not use this file except in compliance with the License.
+     You may obtain a copy of the License at
+
+          http://www.apache.org/licenses/LICENSE-2.0
+
+     Unless required by applicable law or agreed to in writing, software
+     distributed under the License is distributed on an "AS IS" BASIS,
+     WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+     See the License for the specific language governing permissions and
+     limitations under the License.
+-->
+<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="match_parent"
+    android:layout_height="wrap_content">
+  <com.google.android.exoplayer2.ui.TrackSelectionView
+      android:id="@+id/download_dialog_track_selection_view"
+      android:orientation="vertical"
+      android:layout_width="wrap_content"
+      android:layout_height="wrap_content"/>
+</ScrollView>

demos/main/src/main/res/layout/download_track_item.xml

@@ -1,53 +0,0 @@
-<?xml version="1.0" encoding="utf-8"?>
-<!-- Copyright (C) 2018 The Android Open Source Project
-
-     Licensed under the Apache License, Version 2.0 (the "License");
-     you may not use this file except in compliance with the License.
-     You may obtain a copy of the License at
-
-          http://www.apache.org/licenses/LICENSE-2.0
-
-     Unless required by applicable law or agreed to in writing, software
-     distributed under the License is distributed on an "AS IS" BASIS,
-     WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-     See the License for the specific language governing permissions and
-     limitations under the License.
--->
-<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
-    android:layout_width="match_parent"
-    android:layout_height="wrap_content"
-    android:paddingStart="12dp"
-    android:paddingEnd="12dp"
-    android:orientation="horizontal"
-    android:gravity="center_vertical">
-
-  <LinearLayout
-      android:layout_width="0dp"
-      android:layout_height="wrap_content"
-      android:layout_weight="1"
-      android:orientation="vertical">
-
-    <TextView
-        android:id="@+id/track_title"
-        android:textStyle="bold"
-        android:layout_width="wrap_content"
-        android:layout_height="wrap_content"
-        android:paddingTop="4dp"/>
-
-    <TextView
-        android:id="@+id/track_desc"
-        android:layout_width="wrap_content"
-        android:layout_height="wrap_content"
-        android:paddingBottom="4dp"/>
-
-  </LinearLayout>
-
-  <ImageButton
-      android:id="@+id/edit_button"
-      android:layout_width="wrap_content"
-      android:layout_height="wrap_content"
-      android:background="@android:color/transparent"
-      android:contentDescription="@string/download_edit_track"
-      android:src="@drawable/ic_edit"/>
-
-</LinearLayout>

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

@@ -51,10 +51,6 @@
 
   <string name="ima_not_loaded">Playing sample without ads, as the IMA extension was not loaded</string>
 
-  <string name="download_edit_track">Edit selection</string>
-
-  <string name="download_preparing">Preparing download…</string>
-
   <string name="download_start_error">Failed to start download</string>
 
   <string name="download_playlist_unsupported">This demo app does not support downloading playlists</string>