我正在开发一个用于检查互联网连接的android广播接收器。

问题是我的广播接收器被调用了两次。我希望它只在网络可用时被调用。如果它不可用,我不想被通知。

这是广播接收机

public class NetworkChangeReceiver extends BroadcastReceiver {

    @Override
    public void onReceive(final Context context, final Intent intent) {
        final ConnectivityManager connMgr = (ConnectivityManager) context
                .getSystemService(Context.CONNECTIVITY_SERVICE);

        final android.net.NetworkInfo wifi = connMgr
                .getNetworkInfo(ConnectivityManager.TYPE_WIFI);

        final android.net.NetworkInfo mobile = connMgr
                .getNetworkInfo(ConnectivityManager.TYPE_MOBILE);

        if (wifi.isAvailable() || mobile.isAvailable()) {
            // Do something

            Log.d("Network Available ", "Flag No 1");
        }
    }
}

这是manifest.xml

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.broadcastreceiverforinternetconnection"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk
        android:minSdkVersion="8"
        android:targetSdkVersion="17" />
    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>

    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <receiver android:name=".NetworkChangeReceiver" >
            <intent-filter>
                <action android:name="android.net.conn.CONNECTIVITY_CHANGE" />
                <action android:name="android.net.wifi.WIFI_STATE_CHANGED" />
            </intent-filter>
        </receiver>
    </application>

</manifest>

当前回答

1)在manifest: -调用接收器如下代码

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    package="com.safal.checkinternet">

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

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/AppTheme"
        tools:ignore="AllowBackup,GoogleAppIndexingWarning">
        <receiver android:name=".NetworkChangeReceiver" >
            <intent-filter>
                <action android:name="android.net.conn.CONNECTIVITY_CHANGE" />
            </intent-filter>
        </receiver>
        <activity android:name=".MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>

2)创建一个宽播接收器类:在这个类中添加网络检查的代码

package com.safal.checkinternet;

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

public class NetworkChangeReceiver extends BroadcastReceiver {

    @Override
    public void onReceive(final Context context, final Intent intent) {
        if (isOnline(context)){
            Toast.makeText(context, "Available", Toast.LENGTH_SHORT).show();
        }else {
            Toast.makeText(context, "Not Available", Toast.LENGTH_SHORT).show();
        }
    }
    public boolean isOnline(Context context) {

        ConnectivityManager cm = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
        assert cm != null;
        NetworkInfo netInfo = cm.getActiveNetworkInfo();
        return (netInfo != null && netInfo.isConnected());
    }    
} 

3)在您的活动中呼叫广播接收器:-

package com.safal.checkinternet;

import androidx.appcompat.app.AppCompatActivity;

import android.content.Intent;
import android.content.IntentFilter;
import android.os.Bundle;

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
//Call Broad cast Receiver 
        IntentFilter filter = new IntentFilter();
        filter.addAction("android.net.conn.CONNECTIVITY_CHANGE");
        registerReceiver(new NetworkChangeReceiver(), filter);
    }
}

其他回答

public class AsyncCheckInternet extends AsyncTask<String, Void, Boolean> {

public static final int TIME_OUT = 10 * 1000;

private OnCallBack listener;

public interface OnCallBack {

    public void onBack(Boolean value);
}

public AsyncCheckInternet(OnCallBack listener) {
    this.listener = listener;
}

@Override
protected void onPreExecute() {
}

@Override
protected Boolean doInBackground(String... params) {

    ConnectivityManager connectivityManager = (ConnectivityManager) General.context
            .getSystemService(Context.CONNECTIVITY_SERVICE);

    NetworkInfo networkInfo = connectivityManager.getActiveNetworkInfo();

    if ((networkInfo != null && networkInfo.isConnected())
            && ((networkInfo.getType() == ConnectivityManager.TYPE_WIFI) || (networkInfo
                    .getType() == ConnectivityManager.TYPE_MOBILE))) {
        HttpURLConnection urlc;
        try {
            urlc = (HttpURLConnection) (new URL("http://www.google.com")
                    .openConnection());
            urlc.setConnectTimeout(TIME_OUT);
            urlc.connect();
            if (urlc.getResponseCode() == HttpURLConnection.HTTP_OK) {
                return true;
            } else {
                return false;
            }
        } catch (MalformedURLException e) {
            e.printStackTrace();
            return false;

        } catch (IOException e) {
            e.printStackTrace();
            return false;

        }
    } else {
        return false;
    }
}

@Override
protected void onPostExecute(Boolean result) {
    if (listener != null) {
        listener.onBack(result);
    }
}

}

检查网络状态:

private void checkInternetConnection() {

    if (br == null) {

        br = new BroadcastReceiver() {

            @Override
            public void onReceive(Context context, Intent intent) {

                Bundle extras = intent.getExtras();

                NetworkInfo info = (NetworkInfo) extras
                        .getParcelable("networkInfo");

                State state = info.getState();
                Log.d("TEST Internet", info.toString() + " "
                        + state.toString());

                if (state == State.CONNECTED) {
                      Toast.makeText(getApplicationContext(), "Internet connection is on", Toast.LENGTH_LONG).show();

                } else {
                       Toast.makeText(getApplicationContext(), "Internet connection is Off", Toast.LENGTH_LONG).show();
                }

            }
        };

        final IntentFilter intentFilter = new IntentFilter();
        intentFilter.addAction(ConnectivityManager.CONNECTIVITY_ACTION);
        registerReceiver((BroadcastReceiver) br, intentFilter);
    }
}

记得在onDestroy中注销服务。

干杯! !

public class NetworkChangeReceiver extends BroadcastReceiver {

    @Override
    public void onReceive(final Context context, final Intent intent) {
        if (checkInternet(context)) {
            Toast.makeText(context, "Network Available Do operations", Toast.LENGTH_LONG).show();
        }
    }

    boolean checkInternet(Context context) {
        ServiceManager serviceManager = new ServiceManager(context);
        return serviceManager.isNetworkAvailable()
    }
}

ServiceManager.java

public class ServiceManager {

    Context context;

    public ServiceManager(Context base) {
        context = base;
    }

    public boolean isNetworkAvailable() {
        ConnectivityManager cm = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
        NetworkInfo networkInfo = cm.getActiveNetworkInfo();
        return networkInfo != null && networkInfo.isConnected();
    }
}

权限:

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

试试这个

public class ConnectionBroadcastReceiver extends BroadcastReceiver {
@Override
public void onReceive(Context context, Intent intent) {


    if (<Check internet connection available >) { 
        Toast.makeText(context, "connect to the internet", Toast.LENGTH_LONG).show();

        /*upload background upload service*/
        Intent serviceIntent = new Intent(context,<your service class>);
        context.startService(serviceIntent);


    }else{
        Toast.makeText(context, "Connection failed", Toast.LENGTH_LONG).show();

    }
    }
}

一旦互联网连接触发,这(BroadcastReciever)将被加载

public static boolean isNetworkAvailable(Context context) {
        boolean isMobile = false, isWifi = false;

        NetworkInfo[] infoAvailableNetworks = getConnectivityManagerInstance(
                context).getAllNetworkInfo();

        if (infoAvailableNetworks != null) {
            for (NetworkInfo network : infoAvailableNetworks) {

                if (network.getType() == ConnectivityManager.TYPE_WIFI) {
                    if (network.isConnected() && network.isAvailable())
                        isWifi = true;
                }
                if (network.getType() == ConnectivityManager.TYPE_MOBILE) {
                    if (network.isConnected() && network.isAvailable())
                        isMobile = true;
                }
            }
        }

        return isMobile || isWifi;
    }

/* You can write such method somewhere in utility class and call it NetworkChangeReceiver like below */
public class NetworkChangedReceiver extends BroadcastReceiver 
{
@Override
    public void onReceive(Context context, Intent intent) {

        if (isNetworkAvailable(context)) 
                {
             Toast.makeText(context, "Network Available Do operations",Toast.LENGTH_LONG).show(); 


    }
    }
}

只有当网络状态变为已连接而不是已断开时,才会调用上述广播接收器。