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>
我知道这个帖子已经很老了，而且已经有了完整的答案，但我觉得下面的帖子可能会帮助到一些人。
问题主体中的代码包含一个这里没有人解决的错误。
@Nikhil正在检查wifi/手机是否可用，而不是是否连接。
解决方法如下:
@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.isConnected() || mobile.isConnected()) {
// do stuff
}
}
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 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" />
警告:为android.net.conn.CONNECTIVITY_CHANGE声明一个broadcastreceiver对于目标为N或更高的应用程序是不建议使用的。一般来说，应用程序不应该依赖于这个广播，而是使用JobScheduler或GCMNetworkManager。
由于CONNECTIVITY_CHANGE已弃用，那么我们应该使用另一种方式来做相同的事情
接下来的NetworkConnectionLiveData将处理所有的OS Version，直到现在，如果目标SDK小于Build.VERSION_CODES。棒棒糖，那么只有我们可以使用broadcastReceiver
最好的部分是这个类使用LiveData，所以不需要注册任何接收器使用LiveData，它将处理所有的事情
class NetworkConnectionLiveData(val context: Context) : LiveData<Boolean>() {
private var connectivityManager: ConnectivityManager = context.getSystemService(CONNECTIVITY_SERVICE) as ConnectivityManager
private lateinit var connectivityManagerCallback: ConnectivityManager.NetworkCallback
override fun onActive() {
super.onActive()
updateConnection()
when {
Build.VERSION.SDK_INT >= Build.VERSION_CODES.N -> connectivityManager.registerDefaultNetworkCallback(getConnectivityManagerCallback())
Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP -> lollipopNetworkAvailableRequest()
else -> {
if (Build.VERSION.SDK_INT < Build.VERSION_CODES.LOLLIPOP) {
context.registerReceiver(networkReceiver, IntentFilter("android.net.conn.CONNECTIVITY_CHANGE"))
}
}
}
}
override fun onInactive() {
super.onInactive()
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
connectivityManager.unregisterNetworkCallback(connectivityManagerCallback)
} else {
context.unregisterReceiver(networkReceiver)
}
}
@TargetApi(Build.VERSION_CODES.LOLLIPOP)
private fun lollipopNetworkAvailableRequest() {
val builder = NetworkRequest.Builder()
.addTransportType(android.net.NetworkCapabilities.TRANSPORT_CELLULAR)
.addTransportType(android.net.NetworkCapabilities.TRANSPORT_WIFI)
connectivityManager.registerNetworkCallback(builder.build(), getConnectivityManagerCallback())
}
private fun getConnectivityManagerCallback(): ConnectivityManager.NetworkCallback {
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
connectivityManagerCallback = object : ConnectivityManager.NetworkCallback() {
override fun onAvailable(network: Network?) {
postValue(true)
}
override fun onLost(network: Network?) {
postValue(false)
}
}
return connectivityManagerCallback
} else {
throw IllegalAccessError("Should not happened")
}
}
private val networkReceiver = object : BroadcastReceiver() {
override fun onReceive(context: Context, intent: Intent) {
updateConnection()
}
}
private fun updateConnection() {
val activeNetwork: NetworkInfo? = connectivityManager.activeNetworkInfo
postValue(activeNetwork?.isConnected == true)
}
}
使用LiveData到任何类:
NetworkConnectionLiveData(context ?: return)
.observe(viewLifecycleOwner, Observer { isConnected ->
if (!isConnected) {
// Internet Not Available
return@Observer
}
// Internet Available
})
