我们的应用有时候需要检测网络断开，并且给用户友好的提示。根据需求，我们觉得利用Android系统广播，当我们收到断开网络的时候，我们弹出一个Dialog。这个时候我们需要新建一个BaseActivity。
package com.wj.networkcheckdemo.base;
import android.app.Activity;
import android.app.AlertDialog;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.IntentFilter;
import android.net.ConnectivityManager;
import android.net.NetworkInfo;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import com.wj.networkcheckdemo.R;
import com.wj.networkcheckdemo.bean.ActivityController;
public class BaseActivity extends AppCompatActivity {
private NetWorkChangeBroadcastReceiver myReceiver;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_base);
ActivityController.setCurrentActivity(this);
myReceiver = new NetWorkChangeBroadcastReceiver();
IntentFilter filter = new IntentFilter();
filter.addAction("android.net.conn.CONNECTIVITY_CHANGE");
registerReceiver(myReceiver, filter);
}
class NetWorkChangeBroadcastReceiver extends BroadcastReceiver {
@Override
public void onReceive(Context context, Intent intent) {
ConnectivityManager connectivityManager =
(ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
if (connectivityManager != null) {
NetworkInfo[] networkInfos = connectivityManager.getAllNetworkInfo();
for (int i = 0; i < networkInfos.length; i++) {
NetworkInfo.State state = networkInfos[i].getState();
if (NetworkInfo.State.CONNECTED == state) {
//有网络,直接跳出该方法
return;
}
}
}
final Activity activity = ActivityController.getCurrentActivity();//Dialog依托于Activity。所以该方法用户存储唯一可视的Activity
if (activity != null) {
showDialog(activity);
}
}
}
public void showDialog(Context context) {
AlertDialog.Builder dialog = new AlertDialog.Builder(context);
dialog.setTitle("提示")
.setMessage("您已经断网了,是否重新连接")
.setCancelable(false)
.setPositiveButton("确定", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
}
}).setNegativeButton("取消", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
}
});
dialog.create().show();
}
@Override
protected void onDestroy() {
super.onDestroy();
unregisterReceiver(myReceiver);
}
}
我们知道Dialog是依托在Activity之上的。所以我们保存了一个Activity对象。
最后别忘记添加两个重要的权限。
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
