从零开始学android<AudioManager 声音编辑器.五十.>

我们在使用android手机的时候往往会用到声音的增大和缩小操作，在设置情景模式的时候往往会用到静音和震动的操作，这往往就是由AudioManager来控制的。

今天我们就来看一下AudioManager
的使用。

首先要想操作声音必须取得这个服务，在前面我们学过取得系统服务的方法

AudioManager audio = (AudioManager) super.getSystemService(Context.AUDIO_SERVICE);

然后用这个类中的方法来操作声音组件，接下来用例子进行说明

xml

<RelativeLayout 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:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context=".MainActivity" >

    <ImageButton
        android:id="@+id/imageButton3"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignTop="@+id/imageButton4"
        android:layout_toLeftOf="@+id/imageButton4"
        android:src="@drawable/voiceup" />

    <ImageButton
        android:id="@+id/imageButton1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentLeft="true"
        android:layout_alignTop="@+id/imageButton2"
        android:src="@drawable/music" />

    <ImageButton
        android:id="@+id/imageButton2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignTop="@+id/imageButton5"
        android:layout_toRightOf="@+id/imageButton1"
        android:src="@drawable/novoice" />

    <ImageButton
        android:id="@+id/imageButton4"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentRight="true"
        android:layout_alignParentTop="true"
        android:layout_marginTop="18dp"
        android:src="@drawable/voicedown" />

    <ImageButton
        android:id="@+id/imageButton5"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignBottom="@+id/imageButton3"
        android:layout_alignTop="@+id/imageButton3"
        android:layout_toLeftOf="@+id/imageButton3"
        android:layout_toRightOf="@+id/imageButton2"
        android:src="@drawable/vibrate" />

</RelativeLayout>

JAVA文件

<span style="font-size:18px;">package com.example.audiomanager;

import java.io.IOException;

import android.app.Activity;
import android.content.Context;
import android.media.AudioManager;
import android.media.MediaPlayer;
import android.os.Bundle;
import android.view.View;
import android.widget.ImageButton;
import android.widget.Toast;

public class MainActivity extends Activity {
	private ImageButton voiceOn, voiceOff, voiceUp, voiceDown, vibate;
	private AudioManager audio;

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		voiceOn = (ImageButton) this.findViewById(R.id.imageButton1);
		voiceOff = (ImageButton) this.findViewById(R.id.imageButton2);
		voiceUp = (ImageButton) this.findViewById(R.id.imageButton3);
		voiceDown = (ImageButton) this.findViewById(R.id.imageButton4);
		vibate = (ImageButton) this.findViewById(R.id.imageButton5);
//		创建Mediaplayer对象，并设置播放资源
		MediaPlayer media = MediaPlayer.create(MainActivity.this, R.raw.fukua);
		try {
//		、准备播放
			media.prepare();
		} catch (IllegalStateException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch (IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
//		进入软件自动播放音乐
		media.start();

//		取得AudioManager对象
		audio = (AudioManager) super.getSystemService(Context.AUDIO_SERVICE);

//		一下为各个按钮设置的监听事件
		voiceOn.setOnClickListener(new View.OnClickListener() {

			@Override
			public void onClick(View v) {
				// TODO Auto-generated method stub
				MainActivity.this.audio
						.setRingerMode(AudioManager.RINGER_MODE_NORMAL);
				Toast.makeText(MainActivity.this, "手机音量开启", Toast.LENGTH_SHORT).show();
			}
		});

		voiceOff.setOnClickListener(new View.OnClickListener() {

			@Override
			public void onClick(View v) {
				// TODO Auto-generated method stub
				MainActivity.this.audio
						.setRingerMode(AudioManager.RINGER_MODE_SILENT);
				Toast.makeText(MainActivity.this, "手机静音", Toast.LENGTH_SHORT).show();
			}
		});

		voiceUp.setOnClickListener(new View.OnClickListener() {

			@Override
			public void onClick(View v) {
				// TODO Auto-generated method stub
				MainActivity.this.audio.adjustVolume(AudioManager.ADJUST_RAISE,
						0);
				Toast.makeText(MainActivity.this, "手机音量增大", Toast.LENGTH_SHORT).show();
			}
		});
		voiceDown.setOnClickListener(new View.OnClickListener() {

			@Override
			public void onClick(View v) {
				// TODO Auto-generated method stub
				MainActivity.this.audio.adjustVolume(AudioManager.ADJUST_LOWER,
						0);
				Toast.makeText(MainActivity.this, "手机音量减小", Toast.LENGTH_SHORT).show();
			}
		});
		vibate.setOnClickListener(new View.OnClickListener() {

			@Override
			public void onClick(View v) {
				// TODO Auto-generated method stub
				MainActivity.this.audio
						.setRingerMode(AudioManager.RINGER_MODE_VIBRATE);
				Toast.makeText(MainActivity.this, "手机为振动模式", Toast.LENGTH_SHORT).show();
			}
		});
	}

}
</span>

点击屏幕上的几个按钮就能实现相应的操作，大家可以根据这几节学到的东西自己实现一个简单的音乐播放器。

下节预报：Viewpaper组件的使用