android - 通过 "assets"文件夹下的文件夹用ExoPlayer播放视频

Question

我正在尝试使用 ExoPlayer 播放视频API 和使用版本的 exoplayer 库:'com.google.android.exoplayer:exoplayer:2.8.1' .我想播放一个名为 video.mp4 的视频它位于名为 folder1 的文件夹中这个文件夹在文件夹内 assets在res (res/assets/folder1/video.mp4)。我无法获取播放视频的代码。请帮助我。

我的 MainActivity.java :

package com.example.amandeep.example2;

import android.content.pm.ActivityInfo;
import android.net.Uri;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.widget.ArrayAdapter;

import com.google.android.exoplayer2.C;
import com.google.android.exoplayer2.ExoPlayerFactory;
import com.google.android.exoplayer2.Format;
import com.google.android.exoplayer2.SimpleExoPlayer;
import com.google.android.exoplayer2.source.ConcatenatingMediaSource;
import com.google.android.exoplayer2.source.ExtractorMediaSource;
import com.google.android.exoplayer2.source.MediaSource;
import com.google.android.exoplayer2.source.MergingMediaSource;
import com.google.android.exoplayer2.source.SingleSampleMediaSource;
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.ui.PlayerView;
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.MimeTypes;
import com.google.android.exoplayer2.util.Util;

import java.util.ArrayList;

public class MainActivity extends AppCompatActivity
{
    SimpleExoPlayer video_player;
    PlayerView player_screen;
    DefaultTrackSelector track_selector;
    DefaultBandwidthMeter band_width_meter = new DefaultBandwidthMeter();

    MediaSource mediaSource;

    @Override
    protected void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        this.setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);

        player_screen = findViewById (R.id.player_screen);
        player_screen.requestFocus();

        TrackSelection.Factory video_track_selection_factory = new AdaptiveTrackSelection.Factory(band_width_meter);
        track_selector = new DefaultTrackSelector(video_track_selection_factory);
        video_player = ExoPlayerFactory.newSimpleInstance(this, track_selector);

        player_screen.setPlayer(video_player);
        video_player.setPlayWhenReady(true);

        DataSource.Factory data_source_factory = new DefaultDataSourceFactory(this, Util.getUserAgent(this, "Application Name"), new DefaultBandwidthMeter());
        Uri url = Uri.parse("file:///android_asset/folder/video.mp4");
        mediaSource = new ExtractorMediaSource.Factory(data_source_factory).createMediaSource(url);

        video_player.prepare(mediaSource);
    }
}

我的 activity_main.xml :

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.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="match_parent"
    tools:context=".MainActivity">

    <com.google.android.exoplayer2.ui.PlayerView
        android:id="@+id/player_screen"
        android:layout_width="0dp"
        android:layout_height="0dp"
        android:layout_gravity="center"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:use_controller="true" />

</android.support.constraint.ConstraintLayout>

注意:我想使用 Uri.parse方法。

如果有人不能正确理解我的问题，请在下方评论。

如果 URI.PARSE 方法无法使用 Assets 中的文件，请告诉我

Answer 1

ExoPlayer 2.12 引入了 MediaItem 类，因此您可以:

val firstVideoUri = Uri.parse("asset:///localfile.mp4")
val firstItem = MediaItem.fromUri(firstVideoUri)
player.addMediaItem(firstItem)

请注意，URI 应以 asset:/// 而非 assets:/// 开头