DeferredMediaSource.java

package com.google.android.exoplayer2.demo;


import android.support.annotation.Nullable;

import com.google.android.exoplayer2.ExoPlayer;
import com.google.android.exoplayer2.Timeline;
import com.google.android.exoplayer2.source.DeferredMediaPeriod;
import com.google.android.exoplayer2.source.DynamicConcatenatingMediaSource.DeferredTimeline;
import com.google.android.exoplayer2.source.MediaPeriod;
import com.google.android.exoplayer2.source.MediaSource;
import com.google.android.exoplayer2.upstream.Allocator;

import java.io.IOException;

public class DeferredMediaSource implements MediaSource {

    private DeferredTimeline deferredTimeline = new DeferredTimeline();
    private ExoPlayer player;
    private boolean isTopLevelSource;
    private Listener listener;

    private MediaSource lazyPrepareMediaSource;
    private boolean prepared = false;
    private boolean createdMediaPeriod = false;

    public DeferredMediaSource(MediaSource lazyPrepareMediaSource) {
        this.lazyPrepareMediaSource = lazyPrepareMediaSource;
    }

    @Override
    public void prepareSource(ExoPlayer player, boolean isTopLevelSource, Listener listener) {
        this.player = player;
        this.isTopLevelSource = isTopLevelSource;
        this.listener = listener;
        listener.onSourceInfoRefreshed(this, deferredTimeline, null);
    }

    @Override
    public void maybeThrowSourceInfoRefreshError() throws IOException {
        if (prepared) {
            lazyPrepareMediaSource.maybeThrowSourceInfoRefreshError();
        }
    }

    @Override
    public MediaPeriod createPeriod(MediaPeriodId id, Allocator allocator) {
        if (prepared) {
            return lazyPrepareMediaSource.createPeriod(id, allocator);
        } else {
            final DeferredMediaPeriod deferredMediaPeriod = new DeferredMediaPeriod(
                    this, id, allocator);
            lazyPrepareMediaSource.prepareSource(player, isTopLevelSource, new Listener() {
                @Override
                public void onSourceInfoRefreshed(MediaSource source, Timeline timeline, @Nullable Object manifest) {
                    deferredTimeline = deferredTimeline.cloneWithNewTimeline(timeline);
                    listener.onSourceInfoRefreshed(DeferredMediaSource.this,
                            deferredTimeline, manifest);
                    if (!createdMediaPeriod) {
                        deferredMediaPeriod.createPeriod();
                        createdMediaPeriod = true;
                    }
                }
            });
            prepared = true;
            return deferredMediaPeriod;
        }
    }

    @Override
    public void releasePeriod(MediaPeriod mediaPeriod) {
        if (mediaPeriod instanceof DeferredMediaPeriod
                && ((DeferredMediaPeriod) mediaPeriod).mediaSource == this) {
            ((DeferredMediaPeriod) mediaPeriod).releasePeriod();
        } else {
            lazyPrepareMediaSource.releasePeriod(mediaPeriod);
        }
    }

    @Override
    public void releaseSource() {
        lazyPrepareMediaSource.releaseSource();
    }

}