package com.example.a17broadcast.test6.test617broadcast;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.widget.Toast;
// TODO: 2017-06-17
public class MainActivity extends AppCompatActivity {
//過濾器
IntentFilter intentFilter;
//廣播
NetworkChangeRecevier networkChangeRecevier;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
intentFilter = new IntentFilter();
//進行過濾,對於網絡廣播的監聽,當網絡發生改變,系統給我的提示就是這些。就是說看我們需要監聽什麼廣播
intentFilter.addAction("android.net.conn.CONNECTIVITY_CHANGE");
networkChangeRecevier = new NetworkChangeRecevier();
//註冊廣播
registerReceiver(networkChangeRecevier, intentFilter);
}
@Override
protected void onDestroy() {
super.onDestroy();
//動態註冊廣播之後需要進行註銷廣播
unregisterReceiver(networkChangeRecevier);
}
//設置內部類進行網絡改變的測試
class NetworkChangeRecevier extends BroadcastReceiver {
@Override
public void onReceive(Context context, Intent intent) {
Toast.makeText(MainActivity.this, "網絡改變", Toast.LENGTH_SHORT).show();
}
}
}
注意可以選擇進行網絡是否存在判斷,只需把內部類中方法進行改變
//設置內部類進行網絡改變的測試
class NetworkChangeRecevier extends BroadcastReceiver {
@Override
public void onReceive(Context context, Intent intent) {
//根據系統服務類得到connectactivitymanger,這是一個系統服務類專門用於網絡管理
ConnectivityManager connectactivitymanger = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo networkinfo = connectactivitymanger.getActiveNetworkInfo();
if (networkinfo != null && networkinfo.isAvailable()) {
Toast.makeText(MainActivity.this, "網絡存在", Toast.LENGTH_SHORT).show();
} else {
Toast.makeText(MainActivity.this, "網絡不存在", Toast.LENGTH_SHORT).show();
}
}
}
自然網絡權限是必須有呢:
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"></uses-permission>