Question

我创建了音乐播放器应用，我想以编程方式设置volume 向上/向下。

我想为另外两个Button实现增加/减少音量并设置为媒体播放器。

请帮助我在 android 中访问音量向上/向下。

活动代码：

control = (ImageView) findViewById(R.id.control);
mediaPlayer = new MediaPlayer();
mediaPlayer.setAudioStreamType(AudioManager.STREAM_MUSIC);
control.setOnClickListener(pausePlay);
control.setBackgroundResource(R.drawable.pause);
control id is my play and pause button :
{
            // TODO Auto-generated method stub
            // TODO Auto-generated method stub

            if (playPause) {
                control.setBackgroundResource(R.drawable.play);
                if (mediaPlayer.isPlaying())
                    mediaPlayer.pause();
                media.stop();
                intialStage = false;
                playPause = false;

            } else {
                control.setBackgroundResource(R.drawable.pause);
                if (intialStage) {
                    new Player()
                            .execute("http://streaming.shoutcast.com/MUKILFMRADIO");
                } else {
                    if (!mediaPlayer.isPlaying())
                        mediaPlayer.start();
                }
                playPause = true;
            }
}

布局代码：

<LinearLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="horizontal"
    android:gravity="center">
    <ImageView
        android:layout_width="40dp"
        android:layout_height="40dp"
        android:id="@+id/control1"
        android:layout_margin="10dp"
        android:layout_gravity="center"
        android:background="@drawable/decrement"
        android:layout_above="@+id/latestAddedSongs"
        android:layout_alignEnd="@+id/musicArtistName" />
    <ImageView
        android:layout_width="70dp"
        android:layout_height="70dp"
        android:id="@+id/control"
        android:layout_margin="10dp"
        android:layout_gravity="center"
        android:background="@drawable/play"
        android:layout_above="@+id/latestAddedSongs"
        android:layout_alignEnd="@+id/musicArtistName" />
    <ImageView
        android:layout_width="40dp"
        android:layout_height="40dp"
        android:id="@+id/control2"
        android:layout_margin="10dp"
        android:layout_gravity="center"
        android:background="@drawable/increment"
        android:layout_above="@+id/latestAddedSongs"
        android:layout_alignEnd="@+id/musicArtistName" />
</LinearLayout>

以编程方式在android中提供关于静音/取消静音和音量向上/向下的链接或教程。

Answer 1

为音频管理器创建一个对象

AudioManager audioManager = (AudioManager) getApplicationContext().getSystemService(Context.AUDIO_SERVICE);


Button upButton = (Button) findViewById(R.id.upButton);
        upButton.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {

//To increase media player volume               
                audioManager.adjustVolume(AudioManager.ADJUST_RAISE, AudioManager.FLAG_PLAY_SOUND);
            }
        });

        Button downButton = (Button) findViewById(R.id.downButton);
        downButton.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {

//To decrease media player volume
                audioManager.adjustVolume(AudioManager.ADJUST_LOWER, AudioManager.FLAG_PLAY_SOUND);             
            }
        });

以上示例使用了Button标签

用于音量增大和减小代码

@Override
    public boolean dispatchKeyEvent(KeyEvent event) {
        int action = event.getAction();
        int keyCode = event.getKeyCode();
        switch (keyCode) {
            case KeyEvent.KEYCODE_VOLUME_UP:
                if (action == KeyEvent.ACTION_DOWN) {
                    audioManager.adjustVolume(AudioManager.ADJUST_RAISE, AudioManager.FLAG_PLAY_SOUND);
                }
                return true;
            case KeyEvent.KEYCODE_VOLUME_DOWN:
                if (action == KeyEvent.ACTION_DOWN) {
                    audioManager.adjustVolume(AudioManager.ADJUST_LOWER, AudioManager.FLAG_PLAY_SOUND);
                }
                return true;
            default:
                return super.dispatchKeyEvent(event);
        }
    }

Answer 2

尝试以下代码

audioManager = (AudioManager) getSystemService(Context.AUDIO_SERVICE);

seekbar.setMax(audioManager.getStreamMaxVolume(AudioManager.STREAM_MUSIC));

seekbar.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
  @Override
  public void onProgressChanged(SeekBar seekBar, int newVolume, boolean b) {
    textview.setText("Media Volume : " + newVolume);
    audioManager.setStreamVolume(AudioManager.STREAM_MUSIC, newVolume, 0);
  }

  @Override
  public void onStartTrackingTouch(SeekBar seekBar) {}

  @Override
  public void onStopTrackingTouch(SeekBar seekBar) {}
});

Answer 3

跟进jesu的解决方案，如果你想在Service而不是Activity中更改音量，请替换：

AudioManager audioManager = (AudioManager) getApplicationContext().getSystemService(Context.AUDIO_SERVICE);

使用：

AudioManager audioManager;
audioManager = (AudioManager) YourServiceName.this.getSystemService(Context.AUDIO_SERVICE);

Answer 4

以下代码效果很好

Android中有多个流可以用来管理音频

 /** The audio stream for phone calls */
    public static final int STREAM_VOICE_CALL = AudioSystem.STREAM_VOICE_CALL;
    /** The audio stream for system sounds */
    public static final int STREAM_SYSTEM = AudioSystem.STREAM_SYSTEM;
    /** The audio stream for the phone ring */
    public static final int STREAM_RING = AudioSystem.STREAM_RING;
    /** The audio stream for music playback */
    public static final int STREAM_MUSIC = AudioSystem.STREAM_MUSIC;
    /** The audio stream for alarms */
    public static final int STREAM_ALARM = AudioSystem.STREAM_ALARM;
    /** The audio stream for notifications */
    public static final int STREAM_NOTIFICATION = AudioSystem.STREAM_NOTIFICATION;
    /** @hide The audio stream for phone calls when connected to bluetooth */
    public static final int STREAM_BLUETOOTH_SCO = AudioSystem.STREAM_BLUETOOTH_SCO;
    /** @hide The audio stream for enforced system sounds in certain countries (e.g camera in Japan) */
    public static final int STREAM_SYSTEM_ENFORCED = AudioSystem.STREAM_SYSTEM_ENFORCED;
    /** The audio stream for DTMF Tones */
    public static final int STREAM_DTMF = AudioSystem.STREAM_DTMF;
    /** @hide The audio stream for text to speech (TTS) */
    public static final int STREAM_TTS = AudioSystem.STREAM_TTS;

根据您的需要，您可以在此处更改流，这是STREAM_MUSIC示例：

您可以使用AudioSytem类中的反射获得恒定值：

 private int getStreamType(String streamName) {
        final String streamSourceClassName = "android.media.AudioSystem";
        int streamType = 0;
        try {
            streamType = (int) Class.forName(streamSourceClassName).getDeclaredField(streamName).get(null);
        } catch (ClassNotFoundException | IllegalAccessException | NoSuchFieldException e) {
            e.printStackTrace();
        }
        return streamType;
    }


audioManager = (AudioManager) getSystemService(Context.AUDIO_SERVICE);

seekbar.setMax(audioManager.getStreamMaxVolume(AudioManager.STREAM_MUSIC));

seekbar.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
  @Override
  public void onProgressChanged(SeekBar seekBar, int newVolume, boolean b) {
    textview.setText("Media Volume : " + newVolume);
    audioManager.setStreamVolume(AudioManager.STREAM_MUSIC, newVolume, 0);
  }

  @Override
  public void onStartTrackingTouch(SeekBar seekBar) {}

  @Override
  public void onStopTrackingTouch(SeekBar seekBar) {}
});

Answer 5

如果您的类型是AudioManager.STREAM_MUSIC：使用此代码，请按电话音量按钮

@Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
    switch (keyCode) {
    case KeyEvent.KEYCODE_VOLUME_UP:
        audio.adjustStreamVolume(
            AudioManager.STREAM_MUSIC,
            AudioManager.ADJUST_RAISE,
            AudioManager.FLAG_PLAY_SOUND | AudioManager.FLAG_SHOW_UI);
        return true;
    case KeyEvent.KEYCODE_VOLUME_DOWN:
        audio.adjustStreamVolume(
            AudioManager.STREAM_MUSIC,
            AudioManager.ADJUST_LOWER,
            AudioManager.FLAG_PLAY_SOUND | AudioManager.FLAG_SHOW_UI);
        return true;
    default:
        break;
    }
    return super.onKeyDown(keyCode, event);
}

Answer 6

当按下buttonSES时，此代码将立即将音量设置为100，而不会反馈给用户。

public void perform_actionSES(View v) {
Button buttonSES = (Button) findViewById(R.id.buttonSES);

AudioManager audioManager = (AudioManager) getSystemService(Context.AUDIO_SERVICE);
audioManager.setStreamVolume(AudioManager.STREAM_MUSIC, 100, 0);  
}

Answer 7

各位程序员。我已经尽力使代码尽可能简单。我希望这对某人有帮助。祝你有美好的一天！

我正在使用：安卓工作室 4.2.2 Build #AI-202.7660.26.42.7486908，建于2021年6月24日运行时版本：11.0.8+10-b944.6842174 amd64 VM：不适用的 OpenJDK 64 位服务器 VM 视窗 10 10.0

对于 MainActivity.java，这里是代码。

package com.tutorial.android.mediaplayertest;

import androidx.appcompat.app.AppCompatActivity;

import android.content.Context;

import android.media.AudioManager;
import android.media.MediaPlayer;

import android.os.Bundle;
import android.widget.Button;

import android.widget.Toast;


public class MainActivity extends AppCompatActivity {

    private MediaPlayer mediaPlayer;
    private AudioManager audioManager;
    private Button play, pause, decVolume, incVolume;


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

        // I want my media player instantiated as soon as the app starts
        mediaPlayer = MediaPlayer.create(this, R.raw.test);

        // play button
        play = findViewById(R.id.play_button);
        play.setOnClickListener(view -> {

            Toast.makeText(this, "Music Start", Toast.LENGTH_SHORT).show();

            mediaPlayer.start();
        });

        // pause button
        pause = findViewById(R.id.pause_button);
        pause.setOnClickListener(view -> {

            Toast.makeText(this, "Pause", Toast.LENGTH_SHORT).show();

            mediaPlayer.pause();
        });


        audioManager = (AudioManager) getApplicationContext().getSystemService(Context.AUDIO_SERVICE);

        // volume down button
        decVolume = findViewById(R.id.volume_down);
        decVolume.setOnClickListener(view -> {
            Toast.makeText(this, "Volume down", Toast.LENGTH_SHORT).show();
            audioManager.adjustVolume(AudioManager.ADJUST_LOWER, AudioManager.FLAG_PLAY_SOUND);
        });

        // volume up button
        incVolume = findViewById(R.id.volume_up);
        incVolume.setOnClickListener(view -> {
            Toast.makeText(this, "Volume up", Toast.LENGTH_SHORT).show();
            audioManager.adjustVolume(AudioManager.ADJUST_RAISE, AudioManager.FLAG_PLAY_SOUND);
        });
    }


}

如果是activity_main.xml：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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"
    android:orientation="vertical"
    tools:context=".MainActivity">

    <Button
        android:id="@+id/play_button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Play" />

    <Button
        android:id="@+id/pause_button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Pause" />

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent">

        <Button
            android:id="@+id/volume_down"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="-" />

        <Button
            android:layout_marginLeft="16dp"
            android:id="@+id/volume_up"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="+" />

    </LinearLayout>

</LinearLayout>

如何在android中以编程方式增加和减少音量

8 个答案: