ExoPlayer onResume（）恢复播放状态

Question

我已经实现了播放器，现在出现了问题。 当视频正在播放并且应用关闭并恢复时，视频屏幕会冻结。 我甚至看到了来自Google的ExoPlayer演示活动以便更好地理解，但我无法通过它在我的应用程序中实现它。 我在这里附加了Player Activity，对于完整代码，我正在共享所有文件的GitHub存储库。

RecipeStepDetailFragment.java

package com.example.android.recipe.ui;

import android.content.Context;
import android.content.res.Configuration;
import android.net.Uri;
import android.os.Bundle;
import android.os.Handler;
import android.support.v4.app.Fragment;
import android.support.v4.content.ContextCompat;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.TextView;
import android.widget.Toast;
import com.example.android.recipe.R;
import com.example.android.recipe.pojo.Recipe;
import com.example.android.recipe.pojo.Step;
import com.google.android.exoplayer2.LoadControl;
import com.google.android.exoplayer2.SimpleExoPlayer;
import com.google.android.exoplayer2.source.ExtractorMediaSource;
import com.google.android.exoplayer2.ui.AspectRatioFrameLayout;
import com.google.android.exoplayer2.ui.SimpleExoPlayerView;
import java.util.ArrayList;
import java.util.List;
import com.google.android.exoplayer2.DefaultLoadControl;
import com.google.android.exoplayer2.ExoPlayerFactory;
import com.google.android.exoplayer2.extractor.DefaultExtractorsFactory;
import com.google.android.exoplayer2.source.MediaSource;
import com.google.android.exoplayer2.trackselection.AdaptiveVideoTrackSelection;
import com.google.android.exoplayer2.trackselection.DefaultTrackSelector;
import com.google.android.exoplayer2.trackselection.TrackSelection;
import com.google.android.exoplayer2.upstream.BandwidthMeter;
import com.google.android.exoplayer2.upstream.DefaultBandwidthMeter;
import com.google.android.exoplayer2.upstream.DefaultDataSourceFactory;
import com.google.android.exoplayer2.util.Util;
import com.squareup.picasso.Picasso;

import static com.example.android.recipe.ui.RecipeActivity.SELECTED_INDEX;
import static com.example.android.recipe.ui.RecipeActivity.SELECTED_RECIPES;
import static com.example.android.recipe.ui.RecipeActivity.SELECTED_STEPS;

public class RecipeStepDetailFragment extends Fragment {
    private SimpleExoPlayerView simpleExoPlayerView;
    private SimpleExoPlayer player;
    private BandwidthMeter bandwidthMeter;
    private ArrayList<Step> steps = new ArrayList<>();
    private int selectedIndex;
    private Handler mainHandler;
    ArrayList<Recipe> recipe;
    String recipeName;
    public RecipeStepDetailFragment() { }
    private ListItemClickListener itemClickListener;
    public interface ListItemClickListener {
        void onListItemClick(List<Step> allSteps,int Index,String recipeName);
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        TextView textView;
        mainHandler = new Handler();
        bandwidthMeter = new DefaultBandwidthMeter();
        itemClickListener =(RecipeDetailActivity)getActivity();
        recipe = new ArrayList<>();
        if(savedInstanceState != null) {
            steps = savedInstanceState.getParcelableArrayList(SELECTED_STEPS);
            selectedIndex = savedInstanceState.getInt(SELECTED_INDEX);
            recipeName = savedInstanceState.getString("Title");
        }
        else {
            steps =getArguments().getParcelableArrayList(SELECTED_STEPS);
            if (steps!=null) {
                steps =getArguments().getParcelableArrayList(SELECTED_STEPS);
                selectedIndex=getArguments().getInt(SELECTED_INDEX);
                recipeName=getArguments().getString("Title");
            }
            else {
                recipe =getArguments().getParcelableArrayList(SELECTED_RECIPES);
                steps=(ArrayList<Step>)recipe.get(0).getSteps();
                selectedIndex=0;
            }
        }
        View rootView = inflater.inflate(R.layout.recipe_step_detail_fragment_body_part, container, false);
        textView = (TextView) rootView.findViewById(R.id.recipe_step_detail_text);
        textView.setText(steps.get(selectedIndex).getDescription());
        textView.setVisibility(View.VISIBLE);
        simpleExoPlayerView = (SimpleExoPlayerView) rootView.findViewById(R.id.playerView);
        simpleExoPlayerView.setResizeMode(AspectRatioFrameLayout.RESIZE_MODE_FIT);
        String videoURL = steps.get(selectedIndex).getVideoURL();
        if (rootView.findViewWithTag("sw600dp-port-recipe_step_detail")!=null) {
           recipeName=((RecipeDetailActivity) getActivity()).recipeName;
           ((RecipeDetailActivity) getActivity()).getSupportActionBar().setTitle(recipeName);
        }
        String imageUrl=steps.get(selectedIndex).getThumbnailURL();
        if (imageUrl!="") {
            Uri builtUri = Uri.parse(imageUrl).buildUpon().build();
            ImageView thumbImage = (ImageView) rootView.findViewById(R.id.thumbImage);
            Picasso.with(getContext()).load(builtUri).into(thumbImage);
        }
        if (!videoURL.isEmpty()) {
            initializePlayer(Uri.parse(steps.get(selectedIndex).getVideoURL()));
            if (rootView.findViewWithTag("sw600dp-land-recipe_step_detail")!=null) {
                getActivity().findViewById(R.id.fragment_container2).setLayoutParams(new LinearLayout.LayoutParams(-1,-2));
                simpleExoPlayerView.setResizeMode(AspectRatioFrameLayout.RESIZE_MODE_FIXED_WIDTH);
            }
            else if (isInLandscapeMode(getContext())){
                textView.setVisibility(View.GONE);
            }
        }
        else {
            player=null;
            simpleExoPlayerView.setForeground(ContextCompat.getDrawable(getContext(), R.drawable.ic_visibility_off_white_36dp));
            simpleExoPlayerView.setLayoutParams(new LinearLayout.LayoutParams(300, 300));
        }
        Button mPrevStep = (Button) rootView.findViewById(R.id.previousStep);
        Button mNextstep = (Button) rootView.findViewById(R.id.nextStep);

        mPrevStep.setOnClickListener(new View.OnClickListener() {
            public void onClick(View view) {
            if (steps.get(selectedIndex).getId() > 0) {
                if (player!=null){
                    player.stop();
                }
                itemClickListener.onListItemClick(steps,steps.get(selectedIndex).getId() - 1,recipeName);
            }
            else {
                Toast.makeText(getActivity(),"You already are in the First step of the recipe", Toast.LENGTH_SHORT).show();
            }
        }});

        mNextstep.setOnClickListener(new View.OnClickListener() {
            public void onClick(View view) {
            int lastIndex = steps.size()-1;
            if (steps.get(selectedIndex).getId() < steps.get(lastIndex).getId()) {
                if (player!=null){
                    player.stop();
                }
                itemClickListener.onListItemClick(steps,steps.get(selectedIndex).getId() + 1,recipeName);
            }
            else {
                Toast.makeText(getContext(),"You already are in the Last step of the recipe", Toast.LENGTH_SHORT).show();
            }
        }});
        return rootView;
    }

    private void initializePlayer(Uri mediaUri) {
        if (player == null) {
            TrackSelection.Factory videoTrackSelectionFactory = new AdaptiveVideoTrackSelection.Factory(bandwidthMeter);
            DefaultTrackSelector trackSelector = new DefaultTrackSelector(mainHandler, videoTrackSelectionFactory);
            LoadControl loadControl = new DefaultLoadControl();
            player = ExoPlayerFactory.newSimpleInstance(getContext(), trackSelector, loadControl);
            simpleExoPlayerView.setPlayer(player);
            String userAgent = Util.getUserAgent(getContext(), "Baking App");
            MediaSource mediaSource = new ExtractorMediaSource(mediaUri, new DefaultDataSourceFactory(getContext(), userAgent), new DefaultExtractorsFactory(), null, null);
            player.prepare(mediaSource);
            player.setPlayWhenReady(true);
        }
    }

    @Override
    public void onSaveInstanceState(Bundle currentState) {
        super.onSaveInstanceState(currentState);
        currentState.putParcelableArrayList(SELECTED_STEPS,steps);
        currentState.putInt(SELECTED_INDEX,selectedIndex);
        currentState.putString("Title",recipeName);
    }

    public boolean isInLandscapeMode( Context context ) {
        return (context.getResources().getConfiguration().orientation == Configuration.ORIENTATION_LANDSCAPE);
    }

    @Override
    public void onDetach() {
        super.onDetach();
        if (player!=null) {
            player.stop();
            player.release();
        }
    }

    @Override
    public void onDestroyView() {
        super.onDestroyView();
        if (player!=null) {
            player.stop();
            player.release();
            player=null;
        }
    }

    @Override
    public void onStop() {
        super.onStop();
        if (player!=null) {
            player.stop();
            player.release();
        }
    }

    @Override
    public void onPause() {
        super.onPause();
        if (player!=null) {
            player.stop();
            player.release();
        }
    }
}

完整的项目存储库： https ： //github.com/mtp2697/Udacity-AndroidDeveloperNanodegree-BakingApp

帮助恢复onPause（）和onResume（）的视频播放器状态

谢谢，Praveen Thirumurugan。

Answer 1

我在提交烘焙应用程序时面临同样的问题，我做了类似这样的事情：

private void initPlayer() {
    // Exoplayer


    // 1. Create a default TrackSelector
    // Handler mainHandler = new Handler();
    videoTrackSelectionFactory = new AdaptiveTrackSelection.Factory(bandwidthMeter);
    trackSelector = new DefaultTrackSelector(videoTrackSelectionFactory);
    RenderersFactory render = new DefaultRenderersFactory(getContext());
    mainHandler = new Handler();
    if (CookieHandler.getDefault() != DEFAULT_COOKIE_MANAGER) {
        CookieHandler.setDefault(DEFAULT_COOKIE_MANAGER);
    }

    // 2. Create a default LoadControl
    LoadControl loadControl = new DefaultLoadControl();

    // 3. Create the player
    recipeVideoPlayer = ExoPlayerFactory.newSimpleInstance(render, trackSelector, loadControl);

    // exoPlayerView = (SimpleExoPlayerView) v.findViewById(R.id.exoplayer_recipe);

    // Set media controller
    mExoplayer.setUseController(true);
    mExoplayer.setControllerVisibilityListener(this);

    mExoplayer.requestFocus();


    // Bind the player to the view.

    mExoplayer.setPlayer(recipeVideoPlayer);

    if (TextUtils.isEmpty(mSteps.getVideoURL())) {

        mExoplayer.setVisibility(View.GONE);


    } else {

        mExoplayer.setVisibility(View.VISIBLE);
        Uri video = Uri.parse(mSteps.getVideoURL());
        DefaultDataSourceFactory dataSourceFactory = new DefaultDataSourceFactory(getContext(), Util.getUserAgent(getContext(), "recipes"), null);
        ExtractorsFactory extractorsFactory = new DefaultExtractorsFactory();

        MediaSource videoSource = new ExtractorMediaSource(video, dataSourceFactory, extractorsFactory, mainHandler, null);
        boolean haveResumePosition = resumeWindow != C.INDEX_UNSET;
        if (haveResumePosition) {
            recipeVideoPlayer.seekTo(resumeWindow, resumePosition);
        }
        recipeVideoPlayer.prepare(videoSource, !haveResumePosition, false);

        recipeVideoPlayer.setPlayWhenReady(true);


        recipeVideoPlayer.addListener(new ExoPlayer.EventListener() {
            @Override
            public void onTimelineChanged(Timeline timeline, Object manifest) {

            }

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

                // Toast.makeText(getContext(), "Track changed" + trackSelections.length, Toast.LENGTH_SHORT).show();
                //


            }

            @Override
            public void onLoadingChanged(boolean isLoading) {

            }

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


            }


            @Override
            public void onPlayerError(ExoPlaybackException error) {
                clearResumePosition();
            }

            @Override
            public void onPositionDiscontinuity() {
                // updateResumePosition();
            }

            @Override
            public void onPlaybackParametersChanged(PlaybackParameters playbackParameters) {

            }


        });
    }


}

---

 private void releasePlayer() {
        if (recipeVideoPlayer != null) {
            updateResumePosition();
            recipeVideoPlayer.stop();
            recipeVideoPlayer.release();
            recipeVideoPlayer = null;
        }
}

---

 @Override
    public void onResume() {
        super.onResume();
        if (recipeVideoPlayer == null) {
            initPlayer();
        }
}

---

  @Override
    public void onPause() {
        super.onPause();
        releasePlayer();

}

你可以在这里推荐我的项目