Android RecyclerView with Exoplayer 動画例

人気のあるExoplayer VideoPlayerを使いながら、RecyclerViewに動画を一覧表示する例です。

以下はそのデモです。

Android RecyclerView with Exoplayer Video Example](https://github.com/quicklearner4991/Exoplayer-VideoPlayer-in-Recyclerview/raw/master/20200607_191355.gif)

ステップ1：プロジェクトの作成

まず、空の AndroidStudio プロジェクトを作成します。

ステップ2: 依存関係

この例では、ビデオスクリーンショットを読み込むための Glide、ビデオを再生するための exoplayer など、いくつかのサードパーティの依存関係を使用しています。

以下は、その依存関係です。

dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar'])
    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
    implementation 'androidx.appcompat:appcompat:1.1.0'
    implementation 'androidx.core:core-ktx:1.2.0'
    implementation 'androidx.constraintlayout:constraintlayout:1.1.3'
    testImplementation 'junit:junit:4.12'
    androidTestImplementation 'androidx.test.ext:junit:1.1.1'
    androidTestImplementation 'androidx.test.espresso:espresso-core:3.2.0'
    implementation 'com.google.android.exoplayer:exoplayer:2.10.8'
    implementation 'org.jsoup:jsoup:1.10.3'

    implementation 'com.github.bumptech.glide:glide:4.9.0'
    annotationProcessor 'com.github.bumptech.glide:compiler:4.9.0'
    implementation 'androidx.recyclerview:recyclerview:1.2.0-alpha03'

}

また、同じ app/build.gradle ファイル内で、Java8 を有効にする必要があります。

    compileOptions {
        sourceCompatibility JavaVersion.VERSION_1_8
        targetCompatibility JavaVersion.VERSION_1_8
    }

ステップ2: レイアウトの設計

このプロジェクトでは、Recyclerviewのアイテムレイアウトと、MainActivityのレイアウトの2つを使用します。

layout_media_list_item.xml (a).

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_margin="8dp"
    android:background="@color/white"
    >

  <TextView
      android:id="@+id/tvTitle"
      android:layout_width="0dp"
      android:layout_height="wrap_content"
      android:layout_marginEnd="8dp"
      android:layout_marginStart="8dp"
      android:layout_marginTop="8dp"
      android:letterSpacing="-0.02"
      android:lineSpacingExtra="5sp"
      android:textColor="@color/navy"
      android:textSize="18sp"
      android:textStyle="bold"
      app:layout_constraintEnd_toEndOf="parent"
      app:layout_constraintStart_toStartOf="parent"
      app:layout_constraintTop_toTopOf="parent"
      />

  <ImageView
      android:id="@+id/imageView"
      android:layout_width="25dp"
      android:layout_height="25dp"
      android:layout_marginBottom="8dp"
      android:layout_marginStart="8dp"
      android:layout_marginTop="8dp"
      app:layout_constraintBottom_toTopOf="@+id/mediaContainer"
      app:layout_constraintStart_toStartOf="parent"
      app:layout_constraintTop_toBottomOf="@+id/tvTitle"
      app:srcCompat="@drawable/ic_user"
      />

  <TextView
      android:id="@+id/tvUserHandle"
      android:layout_width="wrap_content"
      android:layout_height="wrap_content"
      android:layout_marginStart="8dp"
      android:letterSpacing="-0.02"
      android:textColor="@color/windows_blue"
      android:textSize="10sp"
      app:layout_constraintBottom_toBottomOf="@+id/imageView"
      app:layout_constraintStart_toEndOf="@+id/imageView"
      app:layout_constraintTop_toTopOf="@+id/imageView"
      />

  <FrameLayout
      android:id="@+id/mediaContainer"
      android:layout_width="match_parent"
      android:layout_height="300dp"
      android:layout_marginBottom="8dp"
      android:layout_marginEnd="8dp"
      android:layout_marginStart="8dp"
      android:adjustViewBounds="true"
      android:background="@android:color/black"
      android:gravity="center"
      android:scaleType="center"
      app:layout_constraintBottom_toBottomOf="parent"
      app:layout_constraintEnd_toEndOf="parent"
      app:layout_constraintStart_toStartOf="parent"
      app:layout_constraintTop_toBottomOf="@+id/imageView"
      >

    <ImageView
        android:id="@+id/ivMediaCoverImage"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:background="@android:color/white"
        android:scaleType="centerCrop"
        android:src="@drawable/cover"
        />

    <ProgressBar
        android:id="@+id/progressBar"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:visibility="gone"
        style="?android:attr/progressBarStyle"
        />
    <ImageView
        android:id="@+id/ivVolumeControl"
        android:layout_width="25dp"
        android:layout_height="25dp"
        android:layout_gravity="end|bottom"
        android:layout_marginBottom="15dp"
        android:layout_marginEnd="15dp"
        android:alpha="0"
        android:animateLayoutChanges="true"
        android:scaleType="centerCrop"
        android:src="@drawable/ic_volume_on"
        />
  </FrameLayout>

</androidx.constraintlayout.widget.ConstraintLayout>

activity_main.xml ------------------------------------------------------------------------------- <!

ここにカスタムのExoPlayerRecyclerViewを追加します。

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity"
    >

  <com.example.exoplayer.utils.ExoPlayerRecyclerView
      android:id="@+id/exoPlayerRecyclerView"
      android:layout_width="match_parent"
      android:layout_height="match_parent"
      android:background="#dedede"
      android:dividerHeight="8dp"
      />

</androidx.constraintlayout.widget.ConstraintLayout>

ステップ3：モデルオブジェクトの作成

次に、1つのビデオを表現するメディアアイテムオブジェクトを作成します。これらのオブジェクトはそれぞれ、カスタム ExoplayerRecyclerView の1行を占めることになります。

MediaObject.java

package com.example.exoplayer.model;

public class MediaObject {
  private int uId;
  private String title;
  private String mediaUrl;
  private String mediaCoverImgUrl;
  private String userHandle;

  public String getUserHandle() {
    return userHandle;
  }

  public void setUserHandle(String mUserHandle) {
    this.userHandle = mUserHandle;
  }

  public int getId() {
    return uId;
  }

  public void setId(int uId) {
    this.uId = uId;
  }

  public String getTitle() {
    return title;
  }

  public void setTitle(String mTitle) {
    this.title = mTitle;
  }

  public String getUrl() {
    return mediaUrl;
  }

  public void setUrl(String mUrl) {
    this.mediaUrl = mUrl;
  }

  public String getCoverUrl() {
    return mediaCoverImgUrl;
  }

  public void setCoverUrl(String mCoverUrl) {
    this.mediaCoverImgUrl = mCoverUrl;
  }
}

ステップ4：カスタムReyclerviewの作成

ExoplayerRecyclerViewを作成し、動画を表示します。

ExoplayerRecyclerView.javaを作成します。

package com.example.exoplayer.utils;

import android.content.Context;
import android.graphics.Point;
import android.net.Uri;
import android.util.AttributeSet;
import android.util.Log;
import android.view.Display;
import android.view.View;
import android.view.ViewGroup;
import android.view.WindowManager;
import android.widget.FrameLayout;
import android.widget.ImageView;
import android.widget.ProgressBar;

import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import androidx.recyclerview.widget.LinearLayoutManager;
import androidx.recyclerview.widget.RecyclerView;

import com.bumptech.glide.RequestManager;
import com.example.exoplayer.R;
import com.example.exoplayer.adapter.PlayerViewHolder;
import com.example.exoplayer.model.MediaObject;
import com.google.android.exoplayer2.ExoPlaybackException;
import com.google.android.exoplayer2.ExoPlayerFactory;
import com.google.android.exoplayer2.PlaybackParameters;
import com.google.android.exoplayer2.Player;
import com.google.android.exoplayer2.SimpleExoPlayer;
import com.google.android.exoplayer2.Timeline;
import com.google.android.exoplayer2.source.ExtractorMediaSource;
import com.google.android.exoplayer2.source.MediaSource;
import com.google.android.exoplayer2.source.TrackGroupArray;
import com.google.android.exoplayer2.trackselection.AdaptiveTrackSelection;
import com.google.android.exoplayer2.trackselection.DefaultTrackSelector;
import com.google.android.exoplayer2.trackselection.TrackSelection;
import com.google.android.exoplayer2.trackselection.TrackSelectionArray;
import com.google.android.exoplayer2.trackselection.TrackSelector;
import com.google.android.exoplayer2.ui.AspectRatioFrameLayout;
import com.google.android.exoplayer2.ui.PlayerView;
import com.google.android.exoplayer2.upstream.BandwidthMeter;
import com.google.android.exoplayer2.upstream.DataSource;
import com.google.android.exoplayer2.upstream.DefaultBandwidthMeter;
import com.google.android.exoplayer2.upstream.DefaultDataSourceFactory;
import com.google.android.exoplayer2.util.Util;

import java.util.ArrayList;
import java.util.Objects;

public class ExoPlayerRecyclerView extends RecyclerView {

  private static final String TAG = "ExoPlayerRecyclerView";
  private static final String AppName = "Android ExoPlayer";
  /**
   * PlayerViewHolder UI component
   * Watch PlayerViewHolder class
   */
  private ImageView mediaCoverImage, volumeControl;
  private ProgressBar progressBar;
  private View viewHolderParent;
  private FrameLayout mediaContainer;
  private PlayerView videoSurfaceView;
  private SimpleExoPlayer videoPlayer;
  /**
   * variable declaration
   */
  // Media List
  private ArrayList<MediaObject> mediaObjects = new ArrayList<>();
  private int videoSurfaceDefaultHeight = 0;
  private int screenDefaultHeight = 0;
  private Context context;
  private int playPosition = -1;
  private boolean isVideoViewAdded;
  private RequestManager requestManager;
  // controlling volume state
  private VolumeState volumeState;
  private View.OnClickListener videoViewClickListener = new View.OnClickListener() {
    @Override
    public void onClick(View v) {
      toggleVolume();
    }
  };

  public ExoPlayerRecyclerView(@NonNull Context context) {
    super(context);
    init(context);
  }

  public ExoPlayerRecyclerView(@NonNull Context context, @Nullable AttributeSet attrs) {
    super(context, attrs);
    init(context);
  }

  private void init(Context context) {
    this.context = context.getApplicationContext();
    Display display = ((WindowManager) Objects.requireNonNull(
        getContext().getSystemService(Context.WINDOW_SERVICE))).getDefaultDisplay();
    Point point = new Point();
    display.getSize(point);

    videoSurfaceDefaultHeight = point.x;
    screenDefaultHeight = point.y;

    videoSurfaceView = new PlayerView(this.context);
    videoSurfaceView.setResizeMode(AspectRatioFrameLayout.RESIZE_MODE_ZOOM);

    BandwidthMeter bandwidthMeter = new DefaultBandwidthMeter();
    TrackSelection.Factory videoTrackSelectionFactory =
        new AdaptiveTrackSelection.Factory(bandwidthMeter);
    TrackSelector trackSelector =
        new DefaultTrackSelector(videoTrackSelectionFactory);

    //Create the player using ExoPlayerFactory
    videoPlayer = ExoPlayerFactory.newSimpleInstance(context, trackSelector);
    // Disable Player Control
    videoSurfaceView.setUseController(false);
    // Bind the player to the view.
    videoSurfaceView.setPlayer(videoPlayer);
    // Turn on Volume
    setVolumeControl(VolumeState.ON);

    addOnScrollListener(new RecyclerView.OnScrollListener() {
      @Override
      public void onScrollStateChanged(@NonNull RecyclerView recyclerView, int newState) {
        super.onScrollStateChanged(recyclerView, newState);

        if (newState == RecyclerView.SCROLL_STATE_IDLE) {
          if (mediaCoverImage != null) {
            // show the old thumbnail
            mediaCoverImage.setVisibility(VISIBLE);
          }

          // There's a special case when the end of the list has been reached.
          // Need to handle that with this bit of logic
          if (!recyclerView.canScrollVertically(1)) {
            playVideo(true);
          } else {
            playVideo(false);
          }
        }
      }

      @Override
      public void onScrolled(@NonNull RecyclerView recyclerView, int dx, int dy) {
        super.onScrolled(recyclerView, dx, dy);
      }
    });

    addOnChildAttachStateChangeListener(new OnChildAttachStateChangeListener() {
      @Override
      public void onChildViewAttachedToWindow(@NonNull View view) {

      }

      @Override
      public void onChildViewDetachedFromWindow(@NonNull View view) {
        if (viewHolderParent != null && viewHolderParent.equals(view)) {
          resetVideoView();
        }
      }
    });

    videoPlayer.addListener(new Player.EventListener() {
      @Override
      public void onTimelineChanged(Timeline timeline, @Nullable Object manifest, int reason) {

      }

      @Override
      public void onTracksChanged(TrackGroupArray trackGroups,
                                  TrackSelectionArray trackSelections) {

      }

      @Override
      public void onLoadingChanged(boolean isLoading) {

      }

      @Override
      public void onPlayerStateChanged(boolean playWhenReady, int playbackState) {
        switch (playbackState) {

          case Player.STATE_BUFFERING:
            Log.e(TAG, "onPlayerStateChanged: Buffering video.");
            if (progressBar != null) {
              progressBar.setVisibility(VISIBLE);
            }

            break;
          case Player.STATE_ENDED:
            Log.d(TAG, "onPlayerStateChanged: Video ended.");
            videoPlayer.seekTo(0);
            break;
          case Player.STATE_IDLE:

            break;
          case Player.STATE_READY:
            Log.e(TAG, "onPlayerStateChanged: Ready to play.");
            if (progressBar != null) {
              progressBar.setVisibility(GONE);
            }
            if (!isVideoViewAdded) {
              addVideoView();
            }
            break;
          default:
            break;
        }
      }

      @Override
      public void onRepeatModeChanged(int repeatMode) {

      }

      @Override
      public void onShuffleModeEnabledChanged(boolean shuffleModeEnabled) {

      }

      @Override
      public void onPlayerError(ExoPlaybackException error) {

      }

      @Override
      public void onPositionDiscontinuity(int reason) {

      }

      @Override
      public void onPlaybackParametersChanged(PlaybackParameters playbackParameters) {

      }

      @Override
      public void onSeekProcessed() {

      }
    });
  }

  public void playVideo(boolean isEndOfList) {

    int targetPosition;

    if (!isEndOfList) {
      int startPosition = ((LinearLayoutManager) getLayoutManager()).findFirstVisibleItemPosition();
      int endPosition = ((LinearLayoutManager) getLayoutManager()).findLastVisibleItemPosition();

      // if there is more than 2 list-items on the screen, set the difference to be 1
      if (endPosition - startPosition > 1) {
        endPosition = startPosition + 1;
      }

      // something is wrong. return.
      if (startPosition < 0 || endPosition < 0) {
        return;
      }

      // if there is more than 1 list-item on the screen
      if (startPosition != endPosition) {
        int startPositionVideoHeight = getVisibleVideoSurfaceHeight(startPosition);
        int endPositionVideoHeight = getVisibleVideoSurfaceHeight(endPosition);

        targetPosition =
            startPositionVideoHeight > endPositionVideoHeight ? startPosition : endPosition;
      } else {
        targetPosition = startPosition;
      }
    } else {
      targetPosition = mediaObjects.size() - 1;
    }

    Log.d(TAG, "playVideo: target position: " + targetPosition);

    // video is already playing so return
    if (targetPosition == playPosition) {
      return;
    }

    // set the position of the list-item that is to be played
    playPosition = targetPosition;
    if (videoSurfaceView == null) {
      return;
    }

    // remove any old surface views from previously playing videos
    videoSurfaceView.setVisibility(INVISIBLE);
    removeVideoView(videoSurfaceView);

    int currentPosition =
        targetPosition - ((LinearLayoutManager) Objects.requireNonNull(
            getLayoutManager())).findFirstVisibleItemPosition();

    View child = getChildAt(currentPosition);
    if (child == null) {
      return;
    }

    PlayerViewHolder holder = (PlayerViewHolder) child.getTag();
    if (holder == null) {
      playPosition = -1;
      return;
    }
    mediaCoverImage = holder.mediaCoverImage;
    progressBar = holder.progressBar;
    volumeControl = holder.volumeControl;
    viewHolderParent = holder.itemView;
    requestManager = holder.requestManager;
    mediaContainer = holder.mediaContainer;

    videoSurfaceView.setPlayer(videoPlayer);
    viewHolderParent.setOnClickListener(videoViewClickListener);

    DataSource.Factory dataSourceFactory = new DefaultDataSourceFactory(
        context, Util.getUserAgent(context, AppName));
    String mediaUrl = mediaObjects.get(targetPosition).getUrl();
    if (mediaUrl != null) {
      MediaSource videoSource = new ExtractorMediaSource.Factory(dataSourceFactory)
          .createMediaSource(Uri.parse(mediaUrl));
      videoPlayer.prepare(videoSource);
      videoPlayer.setPlayWhenReady(true);
    }
  }

  /**
   * Returns the visible region of the video surface on the screen.
   * if some is cut off, it will return less than the @videoSurfaceDefaultHeight
   */
  private int getVisibleVideoSurfaceHeight(int playPosition) {
    int at = playPosition - ((LinearLayoutManager) Objects.requireNonNull(
        getLayoutManager())).findFirstVisibleItemPosition();
    Log.d(TAG, "getVisibleVideoSurfaceHeight: at: " + at);

    View child = getChildAt(at);
    if (child == null) {
      return 0;
    }

    int[] location = new int[2];
    child.getLocationInWindow(location);

    if (location[1] < 0) {
      return location[1] + videoSurfaceDefaultHeight;
    } else {
      return screenDefaultHeight - location[1];
    }
  }

  // Remove the old player
  private void removeVideoView(PlayerView videoView) {
    ViewGroup parent = (ViewGroup) videoView.getParent();
    if (parent == null) {
      return;
    }

    int index = parent.indexOfChild(videoView);
    if (index >= 0) {
      parent.removeViewAt(index);
      isVideoViewAdded = false;
      viewHolderParent.setOnClickListener(null);
    }
  }

  private void addVideoView() {
    mediaContainer.addView(videoSurfaceView);
    isVideoViewAdded = true;
    videoSurfaceView.requestFocus();
    videoSurfaceView.setVisibility(VISIBLE);
    videoSurfaceView.setAlpha(1);
    mediaCoverImage.setVisibility(GONE);
  }

  private void resetVideoView() {
    if (isVideoViewAdded) {
      removeVideoView(videoSurfaceView);
      playPosition = -1;
      videoSurfaceView.setVisibility(INVISIBLE);
      mediaCoverImage.setVisibility(VISIBLE);
    }
  }

  public void releasePlayer() {

    if (videoPlayer != null) {
      videoPlayer.release();
      videoPlayer = null;
    }

    viewHolderParent = null;
  }

  public void onPausePlayer() {
    if (videoPlayer != null) {
      videoPlayer.stop(true);
    }
  }

  private void toggleVolume() {
    if (videoPlayer != null) {
      if (volumeState == VolumeState.OFF) {
        Log.d(TAG, "togglePlaybackState: enabling volume.");
        setVolumeControl(VolumeState.ON);
      } else if (volumeState == VolumeState.ON) {
        Log.d(TAG, "togglePlaybackState: disabling volume.");
        setVolumeControl(VolumeState.OFF);
      }
    }
  }

  //public void onRestartPlayer() {
  //  if (videoPlayer != null) {
  //   playVideo(true);
  //  }
  //}

  private void setVolumeControl(VolumeState state) {
    volumeState = state;
    if (state == VolumeState.OFF) {
      videoPlayer.setVolume(0f);
      animateVolumeControl();
    } else if (state == VolumeState.ON) {
      videoPlayer.setVolume(1f);
      animateVolumeControl();
    }
  }

  private void animateVolumeControl() {
    if (volumeControl != null) {
      volumeControl.bringToFront();
      if (volumeState == VolumeState.OFF) {
        requestManager.load(R.drawable.ic_volume_off)
            .into(volumeControl);
      } else if (volumeState == VolumeState.ON) {
        requestManager.load(R.drawable.ic_volume_on)
            .into(volumeControl);
      }
      volumeControl.animate().cancel();

      volumeControl.setAlpha(1f);

      volumeControl.animate()
          .alpha(0f)
          .setDuration(600).setStartDelay(1000);
    }
  }

  public void setMediaObjects(ArrayList<MediaObject> mediaObjects) {
    this.mediaObjects = mediaObjects;
  }

  /**
   * Volume ENUM
   */
  private enum VolumeState {
    ON, OFF
  }
}

ステップ5：RecyclerViewアダプターの作成

まず、RecyclerViewのViewHolderを作成します。

(a). PlayerViewHolder.java

package com.example.exoplayer.adapter;

import android.view.View;
import android.widget.FrameLayout;
import android.widget.ImageView;
import android.widget.ProgressBar;
import android.widget.TextView;

import androidx.annotation.NonNull;
import androidx.recyclerview.widget.RecyclerView;

import com.bumptech.glide.RequestManager;
import com.example.exoplayer.R;
import com.example.exoplayer.model.MediaObject;

/**
 * Created on : May 24, 2019
 * Author     : AndroidWave
 */
public class PlayerViewHolder extends RecyclerView.ViewHolder {

  /**
   * below view have public modifier because
   * we have access PlayerViewHolder inside the ExoPlayerRecyclerView
   */
  public FrameLayout mediaContainer;
  public ImageView mediaCoverImage, volumeControl;
  public ProgressBar progressBar;
  public RequestManager requestManager;
  private TextView title, userHandle;
  private View parent;

  public PlayerViewHolder(@NonNull View itemView) {
    super(itemView);
    parent = itemView;
    mediaContainer = itemView.findViewById(R.id.mediaContainer);
    mediaCoverImage = itemView.findViewById(R.id.ivMediaCoverImage);
    title = itemView.findViewById(R.id.tvTitle);
    userHandle = itemView.findViewById(R.id.tvUserHandle);
    progressBar = itemView.findViewById(R.id.progressBar);
    volumeControl = itemView.findViewById(R.id.ivVolumeControl);
  }

  void onBind(MediaObject mediaObject, RequestManager requestManager) {
    this.requestManager = requestManager;
    parent.setTag(this);
    title.setText(mediaObject.getTitle());
    userHandle.setText(mediaObject.getUserHandle());
    this.requestManager
        .load(mediaObject.getCoverUrl())
        .into(mediaCoverImage);
  }
}

(b). MediaRecyclerAdapter.javaを作成します。

package com.example.exoplayer.adapter;

import android.view.LayoutInflater;
import android.view.ViewGroup;

import androidx.annotation.NonNull;
import androidx.recyclerview.widget.RecyclerView;

import com.bumptech.glide.RequestManager;
import com.example.exoplayer.R;
import com.example.exoplayer.model.MediaObject;

import java.util.ArrayList;

public class MediaRecyclerAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {

  private ArrayList<MediaObject> mediaObjects;
  private RequestManager requestManager;

  public MediaRecyclerAdapter(ArrayList<MediaObject> mediaObjects,
                              RequestManager requestManager) {
    this.mediaObjects = mediaObjects;
    this.requestManager = requestManager;
  }

  @NonNull
  @Override
  public RecyclerView.ViewHolder onCreateViewHolder(@NonNull ViewGroup viewGroup, int i) {
    return new PlayerViewHolder(
        LayoutInflater.from(viewGroup.getContext())
            .inflate(R.layout.layout_media_list_item, viewGroup, false));
  }

  @Override
  public void onBindViewHolder(@NonNull RecyclerView.ViewHolder viewHolder, int i) {
    ((PlayerViewHolder) viewHolder).onBind(mediaObjects.get(i), requestManager);
  }

  @Override
  public int getItemCount() {
    return mediaObjects.size();
  }
}

ステップ6：MainActivityの作成

リサイクルビューに動画を追加するなど、すべてを MainActivity クラスにまとめます。

MainActivity.javaを作成します。

package com.example.exoplayer;

import android.os.Bundle;

import androidx.appcompat.app.AppCompatActivity;
import androidx.recyclerview.widget.LinearLayoutManager;

import com.bumptech.glide.Glide;
import com.bumptech.glide.RequestManager;
import com.bumptech.glide.request.RequestOptions;
import com.example.exoplayer.adapter.MediaRecyclerAdapter;
import com.example.exoplayer.model.MediaObject;
import com.example.exoplayer.utils.ExoPlayerRecyclerView;

import java.util.ArrayList;

import static android.widget.LinearLayout.VERTICAL;

public class MainActivity extends AppCompatActivity {

    ExoPlayerRecyclerView mRecyclerView;

    private ArrayList<MediaObject> mediaObjectList = new ArrayList<>();
    private MediaRecyclerAdapter mAdapter;
    private boolean firstTime = true;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        initView();
        // Prepare demo content
        prepareVideoList();

        //set data object
        mRecyclerView.setMediaObjects(mediaObjectList);
        mAdapter = new MediaRecyclerAdapter(mediaObjectList, initGlide());

        //Set Adapter
        mRecyclerView.setAdapter(mAdapter);
        mRecyclerView.smoothScrollToPosition(1);
      //mRecyclerView.smoothScrollToPosition(1);
 /*   if (firstTime) {
      new Handler(Looper.getMainLooper()).post(new Runnable() {
        @Override
        public void run() {
          mRecyclerView.playVideo(false);
        }
      });
      firstTime = false;
    }*/
    }

    private void initView() {
        mRecyclerView = findViewById(R.id.exoPlayerRecyclerView);
        mRecyclerView.setLayoutManager(new LinearLayoutManager(this));
    }

    private RequestManager initGlide() {
        RequestOptions options = new RequestOptions();

        return Glide.with(this)
                .setDefaultRequestOptions(options);
    }

    @Override
    protected void onDestroy() {
        if (mRecyclerView != null) {
            mRecyclerView.releasePlayer();
        }
        super.onDestroy();
    }

    private void prepareVideoList() {
        MediaObject mediaObject = new MediaObject();
        mediaObject.setId(1);
        mediaObject.setUserHandle("User 1");
        mediaObject.setTitle(
                "Item 1");
        mediaObject.setCoverUrl(
                "https://www.muscleandfitness.com/wp-content/uploads/2019/04/7-Demonized-BodyBuilding-Food-Gallery.jpg?w=940&h=529&crop=1");
        mediaObject.setUrl("https://s3.ca-central-1.amazonaws.com/codingwithmitch/media/VideoPlayerRecyclerView/Sending+Data+to+a+New+Activity+with+Intent+Extras.mp4");

        MediaObject mediaObject2 = new MediaObject();
        mediaObject2.setId(2);
        mediaObject2.setUserHandle("user 2");
        mediaObject2.setTitle(
                "Item 2");
        mediaObject2.setCoverUrl(
                "https://www.muscleandfitness.com/wp-content/uploads/2019/04/7-Demonized-BodyBuilding-Food-Gallery.jpg?w=940&h=529&crop=1");
        mediaObject2.setUrl("https://s3.ca-central-1.amazonaws.com/codingwithmitch/media/VideoPlayerRecyclerView/Sending+Data+to+a+New+Activity+with+Intent+Extras.mp4");

        MediaObject mediaObject3 = new MediaObject();
        mediaObject3.setId(3);
        mediaObject3.setUserHandle("User 3");
        mediaObject3.setTitle("Item 3");
        mediaObject3.setCoverUrl(
                "https://www.muscleandfitness.com/wp-content/uploads/2019/04/7-Demonized-BodyBuilding-Food-Gallery.jpg?w=940&h=529&crop=1");
        mediaObject3.setUrl("https://s3.ca-central-1.amazonaws.com/codingwithmitch/media/VideoPlayerRecyclerView/Sending+Data+to+a+New+Activity+with+Intent+Extras.mp4");

        MediaObject mediaObject4 = new MediaObject();
        mediaObject4.setId(4);
        mediaObject4.setUserHandle("User 4");
        mediaObject4.setTitle("Item 4");
        mediaObject4.setCoverUrl(
                "https://www.muscleandfitness.com/wp-content/uploads/2019/04/7-Demonized-BodyBuilding-Food-Gallery.jpg?w=940&h=529&crop=1");
        mediaObject4.setUrl("https://s3.ca-central-1.amazonaws.com/codingwithmitch/media/VideoPlayerRecyclerView/Sending+Data+to+a+New+Activity+with+Intent+Extras.mp4");

        MediaObject mediaObject5 = new MediaObject();
        mediaObject5.setId(5);
        mediaObject5.setUserHandle("User 5");
        mediaObject5.setTitle("Item 5");
        mediaObject5.setCoverUrl(
                "https://www.muscleandfitness.com/wp-content/uploads/2019/04/7-Demonized-BodyBuilding-Food-Gallery.jpg?w=940&h=529&crop=1");
        mediaObject5.setUrl("https://s3.ca-central-1.amazonaws.com/codingwithmitch/media/VideoPlayerRecyclerView/Sending+Data+to+a+New+Activity+with+Intent+Extras.mp4");

        mediaObjectList.add(mediaObject);
        mediaObjectList.add(mediaObject2);
        mediaObjectList.add(mediaObject3);
        mediaObjectList.add(mediaObject4);
        mediaObjectList.add(mediaObject5);
    }
}

ステップ7：インターネット許可の追加

AndroidManifest.xml:\ にインターネットパーミッションを追加します。

    <uses-permission android:name="android.permission.INTERNET" />

実行

コードをコピーするか、以下のリンクからダウンロードし、ビルドして実行します。

参考文献

参考リンクはこちらです。

ダウンロード 例