仅使用ExoPlayer的控制器在Android中播放音频，而无需黑色预览

Question

我想在android中播放一个音频文件列表。正如您所知，当您有视频文件时，使用com.google.android.exoplayer2.ui.PlayerView是有意义的，因为您可以在屏幕上看到视频的内容，而底部有播放/暂停等控制器。但是对于音频文件，如果你让播放音频文件，你会有一个黑屏。我需要的是只使用控制器而不使用黑屏。

有办法做到这一点吗？

第一次编辑：在文档中，我遇到了PlaybackControlView和PlayerControlView。我可以根据自己的情况使用它们吗？如果是，使用哪一个？

第二次编辑：这是我经过一天研究后的结果。我在布局中使用了PlaybackControlView，如下所示：

<com.google.android.exoplayer2.ui.PlaybackControlView
android:id="@+id/play_back_control_view"
android:layout_width="0dp"        <--- I use ConstraintLayout, so this is okay
android:layout_height="wrap_content"
android:background="@color/black"
android:alpha="0.15"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintBottom_toBottomOf="parent"
app:controller_layout_id="@layout/custom_playback_control_view" />

正如您可能从上面的布局中看到的，我使用了一个名为custom_playback_control_view.xml的自定义布局。这是我的自定义布局内容：

<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="@color/black"
xmlns:tools="http://schemas.android.com/tools">
<ImageButton
android:id="@id/exo_play"
style="@style/ExoMediaButton.Play"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
tools:ignore="ContentDescription"/>
<ImageButton android:id="@id/exo_pause"
style="@style/ExoMediaButton.Pause"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
tools:ignore="ContentDescription"/>
<View
android:id="@id/exo_progress_placeholder"
android:layout_width="0dp"
android:layout_weight="1"
android:layout_height="26dp"
app:layout_constraintEnd_toStartOf="@id/exo_duration"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintStart_toEndOf="@id/exo_play"/>
<TextView
android:id="@id/exo_duration"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:includeFontPadding="false"
android:paddingLeft="4dp"
android:paddingRight="4dp"
android:textColor="#FFBEBEBE"
android:textSize="14sp"
android:textStyle="bold"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toEndOf="@id/exo_progress_placeholder"
app:layout_constraintTop_toTopOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>

最后但同样重要的是，我在我的片段：中这样将ExoPlayer连接到PlaybackControlView

myAudioPlayer = ExoPlayerFactory.newSimpleInstance(context)
binding.playBackControlView.player = myAudioPlayer

Answer 1

尝试创建一个像这样的自定义控制器，并将其命名为media_controller.xml

<?xml version="1.0" encoding="utf-8"?>
<layout xmlns:android="http://schemas.android.com/apk/res/android">
<FrameLayout
android:id="@+id/root"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#44000000"
android:focusableInTouchMode="false">
<RelativeLayout
android:id="@+id/controller"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:padding="10dp">

<ImageView
android:id="@+id/play"
android:layout_width="64dp"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:adjustViewBounds="true"
android:padding="2dp"
android:src="@mipmap/ic_media_play" />
<ImageView
android:id="@+id/forward"
android:layout_width="64dp"
android:layout_height="wrap_content"
android:layout_centerVertical="true"
android:layout_toEndOf="@id/play"
android:adjustViewBounds="true"
android:clickable="true"
android:focusable="true"
android:padding="6dp"
android:src="@mipmap/ic_media_forward" />
<ImageView
android:id="@+id/backward"
android:layout_width="64dp"
android:layout_height="wrap_content"
android:layout_centerVertical="true"
android:layout_toStartOf="@id/play"
android:adjustViewBounds="true"
android:clickable="true"
android:focusable="true"
android:padding="6dp"
android:src="@mipmap/ic_media_backward" />

</RelativeLayout>

</FrameLayout>
</layout>

接下来创建一个自定义类ExpoMediaController.java，类似于下面的

public class ExpoMediaController extends FrameLayout implements View.OnClickListener, Player.EventListener{
private LayoutInflater inflater;
Player simpleExoPlayer;
private MediaControllerBinding binding;//media_controller.xml
public ExpoMediaController(Context context, AttributeSet attrs) {
super(context, attrs);
inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
initView();
}

public ExpoMediaController(Context context) {
super(context);
inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
initView();
}

private void initView() {
binding = DataBindingUtil.inflate(inflater, R.layout.media_controller, this, true);
binding.play.setOnClickListener(this);
binding.forward.setOnClickListener(this);
binding.backward.setOnClickListener(this);

}
//Use this method to set and unset the player
public void setPlayer(@Nullable Player simpleExoPlayer) {
if (this.simpleExoPlayer == simpleExoPlayer) {
return;
}
Player oldPlayer = this.simpleExoPlayer;//get reference of old player which attached previously
if (oldPlayer != null) {//if old player not null then clear it
oldPlayer.removeListener(this);
}
this.simpleExoPlayer = simpleExoPlayer;
if (this.simpleExoPlayer != null) {
this.simpleExoPlayer.addListener(this);
}
}
@Override
public void onPlayerStateChanged(boolean playWhenReady, int playbackState) {
switch (playbackState) {
case STATE_BUFFERING:
break;
case STATE_ENDED:
break;
case STATE_IDLE:
break;
case STATE_READY:
if (playWhenReady) {
binding.play.setImageResource(R.mipmap.ic_media_pause);
binding.play.setVisibility(VISIBLE);
} else {
binding.play.setImageResource(R.mipmap.ic_media_play);
binding.play.setVisibility(VISIBLE);
}
break;
default:
break;
}
}
@Override
public void onClick(View v) {
if (v == binding.play && simpleExoPlayer != null) {
if (simpleExoPlayer.isPlaying()) {
simpleExoPlayer.setPlayWhenReady(false);
showControls();
} else {
if (simpleExoPlayer.getPlaybackState() == STATE_ENDED) {
simpleExoPlayer.seekTo(0);
}
simpleExoPlayer.setPlayWhenReady(true);
}
}
}}

在你的活动布局中使用ExpoMediaController来代替com.google.android.exoplayer2.ui.PlaybackControlView。然后调用ExpoMediaControl的setPlayer方法。现在您可以完全控制控制器视图。