Android 判断耳机是否存在

jopen 5年前

AudioManager就有这个方法:isWiredHeadsetOn()

如果插入了耳机,就返回true,否则false;

当然,要加个权限,不然一直是返回false。

 <uses-permission android:name="android.permission.MODIFY_AUDIO_SETTINGS" />

开始我追了好久的源码。发现了实时检测耳机插入和拔出的过程,不过对我的需求来说帮助不是很大。

实时检测耳机插入和拔出:

每当插入和拔出耳机时,系统都会发送Intent广播,所以,只需要用一个receiver把这个广播intent(获取的action是:“android.intent.action.HEADSET_PLUG”)截获就好。

这个receiver必须要用代码注册,而不能写在manifest里面用写入内存的方式。

在Android下实现检测耳机插入和拔出,也即建立一个Broadcast Receiver,监听“android.intent.action.HEADSET_PLUG”广播

但直接在AndroidManifest.xml中添加一个<receiver>标签是无效的,如:

<receiver android:name=".HeadsetPlugReceiver">  <intent-filter>      <action android:name="android.intent.action.HEADSET_PLUG" android:enabled="true"></action>  </intent-filter>  </receiver>

你会发现Receiver的onReceive事件永远不会被触发,解决方法就是手动编写代码注册该广播。

首先,创建一个BroadcastReceiver的子类,用于监听耳机插入和拔出:

public class HeadsetPlugReceiver extends BroadcastReceiver {          private static final String TAG = "HeadsetPlugReceiver";          @Override        public void onReceive(Context context, Intent intent) {          if (intent.hasExtra("state")){            if (intent.getIntExtra("state", 0) == 0){           Toast.makeText(context, "headset not connected", Toast.LENGTH_LONG).show();            }            else if (intent.getIntExtra("state", 0) == 1){              Toast.makeText(context, "headset connected", Toast.LENGTH_LONG).show();            }          }        }  }  

然后,在需要监听该事件的Activity中的onCreate()中注册监听该广播,同时不要忘记在onDestroy()中注销监听该广播:

public class TestHeadSetPlugActivity extends Activity {        private HeadsetPlugReceiver headsetPlugReceiver;      /** Called when the activity is first created. */      @Override      public void onCreate(Bundle savedInstanceState) {          super.onCreate(savedInstanceState);          setContentView(R.layout.main);            /* register receiver */          registerHeadsetPlugReceiver();      }        private void registerHeadsetPlugReceiver() {        headsetPlugReceiver = new HeadsetPlugReceiver();     IntentFilter intentFilter = new IntentFilter();        intentFilter.addAction("android.intent.action.HEADSET_PLUG");        registerReceiver(headsetPlugReceiver, intentFilter);      }        @Override      public void onDestroy() {        unregisterReceiver(headsetPlugReceiver);        super.onDestroy();      } }  

如上这样就可以实现检测耳机插入和拔出了。

参考: http://code.google.com/p/android/issues/detail?id=4963

http://groups.google.com/group/android-developers/browse_thread/thread/6d0dda99b4f42c8f/a9c33e446db4f4d1?#a9c33e446db4f4d1