Android 监测手机联网状态 wifi、移动数据流量、无联网状态

手机当完成联网时会发送一个广播，我们只要创建一个广播接收者即可，代码如下：

package com.example.NetworkChangeReceiver2;

import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.net.ConnectivityManager;
import android.net.NetworkInfo;
import android.widget.Toast;

/**
 * Created by Heyiyong on 2014-4-20 下午2:23.
 */
public class NetworkChangeReceiver extends BroadcastReceiver {
    @Override
    public void onReceive(Context context, Intent intent) {
        ConnectivityManager cm = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
        NetworkInfo activeNetworkInfo = cm.getActiveNetworkInfo();
        if (activeNetworkInfo == null) {
            Toast.makeText(MyActivity.instance, "当前无网络连接！", 1).show();
        }
        if (activeNetworkInfo.getType() == ConnectivityManager.TYPE_WIFI) {
            Toast.makeText(MyActivity.instance, "wifi连接成功！", 1).show();
            return;
        }
        if (activeNetworkInfo.getType() == ConnectivityManager.TYPE_MOBILE) {//当前的connect不是wifi，并且是移动数据
            Toast.makeText(MyActivity.instance, "移动数据流量连接！", 1).show();
            return;
        }
    }
}

MyActivity.java

package com.example.NetworkChangeReceiver2;

import android.app.Activity;
import android.os.Bundle;

public class MyActivity extends Activity {
    public static MyActivity instance;
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        instance = this;
    }
}

注意：不要忘了添加权限：

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

注册广播接收者：

        <receiver
                android:name=".NetworkChangeReceiver"
                android:label="NetworkConnection" >
            <intent-filter>
                <action android:name="android.net.conn.CONNECTIVITY_CHANGE" />
            </intent-filter>
        </receiver>