android实现耳机插入和拔出状态检测

在Android下实现检测耳机插入和拔出，需要建立一个BroadcastReceiver，用来监听"android.intent.action.HEADSET_PLUG"广播。

实现步骤：

1.创建一个BroadcastReceiver的子类，并重写onReceive()方法，在该方法中编写接收到广播后的处理逻辑；

2.创建一个Activity类，在onCreate()方法中使用registerReceiver()方法进行注册监听广播；

3.在Activity中重写onDestory()方法，使用unregisterReceiver()注销监听广播。

具体实现代码如下：

广播接收器类

package com.leigo.demo.receiver;

import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.widget.Toast;

/**
 * Created by Administrator on 2014/8/27.
 */
public class HeadsetDetectReceiver extends BroadcastReceiver {
    @Override
    public void onReceive(Context context, Intent intent) {
        String action = intent.getAction();
        if (Intent.ACTION_HEADSET_PLUG.equals(action)) {
            if (intent.hasExtra("state")) {
                int state = intent.getIntExtra("state", 0);
                if (state == 1) {
                    Toast.makeText(context, "插入耳机", Toast.LENGTH_SHORT).show();
                } else if(state == 0){
                    Toast.makeText(context, "拔出耳机", Toast.LENGTH_SHORT).show();
                }
            }
        }
    }
}

package com.leigo.demo;

import android.app.Activity;
import android.content.BroadcastReceiver;
import android.content.Intent;
import android.content.IntentFilter;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;

import com.leigo.demo.receiver.HeadsetDetectReceiver;

public class MainActivity extends Activity {
    private BroadcastReceiver receiver;

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

        /**
         *  Broadcast Action: Wired Headset plugged in or unplugged
         *  The intent will have the following extra values:
         *  state - 0 for unplugged, 1 for plugged.
         *  name - Headset type, human readable string
         *  microphone - 1 if headset has a microphone, 0 otherwise
         */
        receiver = new HeadsetDetectReceiver();
        IntentFilter intentFilter = new IntentFilter();
        intentFilter.addAction(Intent.ACTION_HEADSET_PLUG);
        registerReceiver(receiver, intentFilter);
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
        unregisterReceiver(receiver);
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();
        if (id == R.id.action_settings) {
            return true;
        }
        return super.onOptionsItemSelected(item);
    }
}