Android判断网络状态方法

public class ConnectionChangeReceiver extends BroadcastReceiver   
{   
    @Override   
    public void onReceive( Context context,Intent intent )   
    {   
        ConnectivityManager connectivityManager = 
            (ConnectivityManager) context.getSystemService( Context.CONNECTIVITY_SERVICE );   
        NetworkInfo activeNetInfo = connectivityManager.getActiveNetworkInfo();   
        NetworkInfo mobNetInfo = connectivityManager.getNetworkInfo( ConnectivityManager.TYPE_MOBILE );   
        if ( activeNetInfo != null )   
        {   
            Toast.makeText( context,"Active Network Type : " + 
            activeNetInfo.getTypeName(),Toast.LENGTH_SHORT ).show();   
        }   
        if( mobNetInfo != null )   
        {   
            Toast.makeText( context,"Mobile Network Type : " + 
            mobNetInfo.getTypeName(),Toast.LENGTH_SHORT ).show();   
        }   
    }   
}   

< !-- Needed to check when the network connection changes -->   
< uses-permission android:name="android.permission.
ACCESS_NETWORK_STATE"/>   
< receiver android:name="com.blackboard.androidtest.
receiver.ConnectionChangeReceiver"   
android:label="NetworkConnection">   
< intent-filter>   
< action android:name="android.net.conn.CONNECTIVITY_CHANGE"/>   
< /intent-filter>   
< /receiver>