我需要检测何时通过 WIFI 进行网络连接。发送什么广播以建立有效的网络连接。我需要验证 HTTP 的有效网络连接是否存在。我应该听什么以及我需要进行哪些额外的测试才能知道存在有效的连接。
15 回答
您可以注册一个BroadcastReceiver
以在建立 WiFi 连接(或连接更改)时收到通知。
注册BroadcastReceiver
:
IntentFilter intentFilter = new IntentFilter();
intentFilter.addAction(WifiManager.SUPPLICANT_CONNECTION_CHANGE_ACTION);
registerReceiver(broadcastReceiver, intentFilter);
然后在你BroadcastReceiver
做这样的事情:
@Override
public void onReceive(Context context, Intent intent) {
final String action = intent.getAction();
if (action.equals(WifiManager.SUPPLICANT_CONNECTION_CHANGE_ACTION)) {
if (intent.getBooleanExtra(WifiManager.EXTRA_SUPPLICANT_CONNECTED, false)) {
//do stuff
} else {
// wifi connection was lost
}
}
}
有关详细信息,请参阅文档BroadcastReceiver
和WifiManager
当然,在此之前您应该检查设备是否已经连接到 WiFi。
编辑:感谢 ban-geoengineering,这是一种检查设备是否已连接的方法:
private boolean isConnectedViaWifi() {
ConnectivityManager connectivityManager = (ConnectivityManager) appObj.getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo mWifi = connectivityManager.getNetworkInfo(ConnectivityManager.TYPE_WIFI);
return mWifi.isConnected();
}
最适合我的:
AndroidManifest
<receiver android:name="com.AEDesign.communication.WifiReceiver" >
<intent-filter android:priority="100">
<action android:name="android.net.wifi.STATE_CHANGE" />
</intent-filter>
</receiver>
广播接收器类
public class WifiReceiver extends BroadcastReceiver {
@Override
public void onReceive(Context context, Intent intent) {
NetworkInfo info = intent.getParcelableExtra(WifiManager.EXTRA_NETWORK_INFO);
if(info != null && info.isConnected()) {
// Do your work.
// e.g. To check the Network Name or other info:
WifiManager wifiManager = (WifiManager)context.getSystemService(Context.WIFI_SERVICE);
WifiInfo wifiInfo = wifiManager.getConnectionInfo();
String ssid = wifiInfo.getSSID();
}
}
}
权限
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE"/>
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
只对我WifiManager.NETWORK_STATE_CHANGED_ACTION
有用。
注册广播接收器:
IntentFilter intentFilter = new IntentFilter();
intentFilter.addAction(WifiManager.NETWORK_STATE_CHANGED_ACTION);
registerReceiver(broadcastReceiver, intentFilter);
并收到:
@Override
public void onReceive(Context context, Intent intent) {
final String action = intent.getAction();
if(action.equals(WifiManager.NETWORK_STATE_CHANGED_ACTION)){
NetworkInfo info = intent.getParcelableExtra(WifiManager.EXTRA_NETWORK_INFO);
boolean connected = info.isConnected();
//call your method
}
}
用户@JPM 和@usman 给出的答案非常有用。它工作正常,但在我的情况下,它在onReceive
我的情况下多次出现4 次,所以我的代码执行多次。
我根据我的要求做了一些修改和制作,现在它只来了 1 次
这是广播的java类。
public class WifiReceiver extends BroadcastReceiver {
String TAG = getClass().getSimpleName();
private Context mContext;
@Override
public void onReceive(Context context, Intent intent) {
mContext = context;
if (intent.getAction().equals(ConnectivityManager.CONNECTIVITY_ACTION)) {
ConnectivityManager cm = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo networkInfo = cm.getActiveNetworkInfo();
if (networkInfo != null && networkInfo.getType() == ConnectivityManager.TYPE_WIFI &&
networkInfo.isConnected()) {
// Wifi is connected
WifiManager wifiManager = (WifiManager) context.getSystemService(Context.WIFI_SERVICE);
WifiInfo wifiInfo = wifiManager.getConnectionInfo();
String ssid = wifiInfo.getSSID();
Log.e(TAG, " -- Wifi connected --- " + " SSID " + ssid );
}
}
else if (intent.getAction().equalsIgnoreCase(WifiManager.WIFI_STATE_CHANGED_ACTION))
{
int wifiState = intent.getIntExtra(WifiManager.EXTRA_WIFI_STATE, WifiManager.WIFI_STATE_UNKNOWN);
if (wifiState == WifiManager.WIFI_STATE_DISABLED)
{
Log.e(TAG, " ----- Wifi Disconnected ----- ");
}
}
}
}
在 AndroidManifest 中
<receiver android:name=".util.WifiReceiver" android:enabled="true">
<intent-filter>
<action android:name="android.net.wifi.WIFI_STATE_CHANGED" />
<action android:name="android.net.conn.CONNECTIVITY_CHANGE"/>
</intent-filter>
</receiver>
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE"/>
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
如果您让用户选择覆盖每次询问的正常行为, 您可以启动 wifi 连接。
我选择使用三种方法...
public boolean isOnline()
{
ConnectivityManager connMgr = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo networkInfo = connMgr.getActiveNetworkInfo();
return (networkInfo != null && networkInfo.isConnected());
}
这是快速检查是否有互联网连接 Wifi 或 CellData。从这里你可以选择你想要采取的行动。是否处于飞行模式也需要检查。
在一个单独的线程上。我将变量 IpAddress 设置为 = " " 并轮询,直到我有一个有效的 IP 地址。
WifiManager wifi;
wifi = (WifiManager) this.getSystemService(Context.WIFI_SERVICE);
WifiInfo wifiInfo = wifi.getConnectionInfo();
int ipAddress = wifiInfo.getIpAddress();
String ip = null;
ip = String.format("%d.%d.%d.%d",
(ipAddress & 0xff),
(ipAddress >> 8 & 0xff),
(ipAddress >> 16 & 0xff),
(ipAddress >> 24 & 0xff));
Log.e(" >>IP number Begin ",ip);
另一个代码片段......如果它没有打开它(在用户事先许可的情况下)
if(wifi.isWifiEnabled()!=true)wifi.setWifiEnabled(true);
为了检测 WIFI 连接状态,我使用了 ConnectivityManager 类中的 CONNECTIVITY_ACTION,所以:
IntentFilter filter=new IntentFilter();
filter.addAction(ConnectivityManager.CONNECTIVITY_ACTION);
registerReceiver(receiver, filter);
并从您的广播接收器:
if (ConnectivityManager.CONNECTIVITY_ACTION.equals(action)) {
int networkType = intent.getIntExtra(
android.net.ConnectivityManager.EXTRA_NETWORK_TYPE, -1);
if (ConnectivityManager.TYPE_WIFI == networkType) {
NetworkInfo networkInfo = (NetworkInfo) intent
.getParcelableExtra(WifiManager.EXTRA_NETWORK_INFO);
if (networkInfo != null) {
if (networkInfo.isConnected()) {
// TODO: wifi is connected
} else {
// TODO: wifi is not connected
}
}
}
}
ps:对我来说很好:)
此代码根本不需要许可。它仅限于 Wi-Fi 网络连接状态更改(不考虑任何其他网络)。接收器静态发布在 AndroidManifest.xml 文件中,不需要导出,因为它会在每次网络连接状态更改时由系统protected broadcast
调用NETWORK_STATE_CHANGED_ACTION
。
安卓清单:
<receiver
android:name=".WifiReceiver"
android:enabled="true"
android:exported="false">
<intent-filter>
<!--protected-broadcast: Special broadcast that only the system can send-->
<!--Corresponds to: android.net.wifi.WifiManager.NETWORK_STATE_CHANGED_ACTION-->
<action android:name="android.net.wifi.STATE_CHANGE" />
</intent-filter>
</receiver>
广播接收器类:
public class WifiReceiver extends BroadcastReceiver {
@Override
public void onReceive(Context context, Intent intent) {
/*
Tested (I didn't test with the WPS "Wi-Fi Protected Setup" standard):
In API15 (ICE_CREAM_SANDWICH) this method is called when the new Wi-Fi network state is:
DISCONNECTED, OBTAINING_IPADDR, CONNECTED or SCANNING
In API19 (KITKAT) this method is called when the new Wi-Fi network state is:
DISCONNECTED (twice), OBTAINING_IPADDR, VERIFYING_POOR_LINK, CAPTIVE_PORTAL_CHECK
or CONNECTED
(Those states can be obtained as NetworkInfo.DetailedState objects by calling
the NetworkInfo object method: "networkInfo.getDetailedState()")
*/
/*
* NetworkInfo object associated with the Wi-Fi network.
* It won't be null when "android.net.wifi.STATE_CHANGE" action intent arrives.
*/
NetworkInfo networkInfo = intent.getParcelableExtra(WifiManager.EXTRA_NETWORK_INFO);
if (networkInfo != null && networkInfo.isConnected()) {
// TODO: Place the work here, like retrieving the access point's SSID
/*
* WifiInfo object giving information about the access point we are connected to.
* It shouldn't be null when the new Wi-Fi network state is CONNECTED, but it got
* null sometimes when connecting to a "virtualized Wi-Fi router" in API15.
*/
WifiInfo wifiInfo = intent.getParcelableExtra(WifiManager.EXTRA_WIFI_INFO);
String ssid = wifiInfo.getSSID();
}
}
}
权限:
None
Android O 消除了接收 wifi 状态更改的隐式广播的可能性。因此,如果您的应用程序已关闭,您将无法接收它们。新WorkManager
的有能力在你的应用程序关闭时运行,所以我对它进行了一些试验,它似乎工作得很好:
将此添加到您的依赖项中:
implementation "android.arch.work:work-runtime:1.0.0-alpha08"
WifiConnectWorker.kt
class WifiConnectWorker : Worker() {
override fun doWork(): Result {
Log.i(TAG, "I think we connected to a wifi")
return Result.SUCCESS
}
}
MainActivity.kt
class MainActivity : AppCompatActivity() {
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.main_activity)
val workManager = WorkManager.getInstance()
// Add constraint to start the worker when connecting to WiFi
val request = OneTimeWorkRequest.Builder(WifiConnectWorker::class.java)
.setConstraints(Constraints.Builder()
.setRequiredNetworkType(UNMETERED)
.build())
.build()
// The worker should be started, even if your app is closed
workManager.beginUniqueWork("watch_wifi", REPLACE, request).enqueue()
}
}
请记住,这只是对一次性通知的快速测试。要在打开和关闭 WiFi 时始终收到通知,还有更多工作要做。
PS:当应用程序被强制退出时,工作人员没有启动,似乎WorkManager
正在取消请求。
这是我的代码示例,它考虑了用户在连接到 Wifi 时只允许通信的偏好。
IntentService
在尝试下载内容之前,我从内部调用此代码。
请注意,NetworkInfo
如果null
没有任何类型的网络连接。
private boolean canConnect()
{
ConnectivityManager connectivityManager = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
boolean canConnect = false;
boolean wifiOnly = SharedPreferencesUtils.wifiOnly();
NetworkInfo networkInfo = connectivityManager.getActiveNetworkInfo();
if(networkInfo != null)
{
if(networkInfo.isConnected())
{
if((networkInfo.getType() == ConnectivityManager.TYPE_WIFI) ||
(networkInfo.getType() != ConnectivityManager.TYPE_WIFI && !wifiOnly))
{
canConnect = true;
}
}
}
return canConnect;
}
我有两种方法来检测接收应用程序上下文的 WIFI 连接:
1)我的旧方法
public boolean isConnectedWifi1(Context context) {
try {
ConnectivityManager connectivityManager = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo networkInfo = connectivityManager.getActiveNetworkInfo();
if (networkInfo != null) {
NetworkInfo[] netInfo = connectivityManager.getAllNetworkInfo();
for (NetworkInfo ni : netInfo) {
if ((ni.getTypeName().equalsIgnoreCase("WIFI"))
&& ni.isConnected()) {
return true;
}
}
}
return false;
} catch (Exception e) {
Log.e(TAG, e.getMessage());
}
return false;
}
2)我的新方法(我目前正在使用这种方法):
public boolean isConnectedWifi(Context context) {
ConnectivityManager connectivityManager = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo networkInfo = connectivityManager.getNetworkInfo(ConnectivityManager.TYPE_WIFI);
return networkInfo.isConnected();
}
1) 我也尝试了广播接收器方法,即使我知道CONNECTIVITY_ACTION/CONNECTIVITY_CHANGE在 API 28 中已弃用且不推荐使用。也必须使用显式注册,只要应用程序正在运行,它就会监听。
2)我还尝试了 Firebase Dispatcher,它可以工作但不能超出应用程序被杀死的范围。
3) 推荐的方法是 WorkManager 以保证在进程被杀死和内部使用registerNetworkRequest()之后执行
支持#3 方法的最大证据是Android 文档本身。特别是对于后台应用程序。
也在这里
在 Android 7.0 中,我们移除了三个常用的隐式广播——CONNECTIVITY_ACTION、ACTION_NEW_PICTURE 和 ACTION_NEW_VIDEO——因为它们会同时唤醒多个应用程序的后台进程并消耗内存和电池。如果您的应用正在接收这些,请利用 Android 7.0 迁移到 JobScheduler 和相关 API。
到目前为止,使用 Periodic WorkManager 请求对我们来说效果很好。
更新:我最终写了 2 个关于它的系列媒体文章。
2020 年 11 月:
我已经处理了太多被 Google 弃用的项目。最后,我找到了一个解决方案,使用谷歌目前建议的“registerNetworkCallback”。
我需要的是一种简单的方法来检测我的设备是否在 WIFI 中分配了 IPv4。(我没有尝试过其他案例,我的要求非常具体,但也许这种方法,没有弃用的元素,将作为其他案例的基础)。
在 API 23、24 和 26(物理设备)和 API 28 和 29(模拟设备)上进行了测试。
ConnectivityManager cm
= (ConnectivityManager) this.getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkRequest.Builder builder = new NetworkRequest.Builder();
cm.registerNetworkCallback
(
builder.build(),
new ConnectivityManager.NetworkCallback()
{
@Override
public void onAvailable(Network network)
{
//Actions to take with Wifi available.
}
@Override
public void onLost(Network network)
{
//Actions to take with lost Wifi.
}
}
);
(在“MainActivity.Oncreate”中实现)
注意:在清单中需要“android.permission.ACCESS_NETWORK_STATE”
我使用了这段代码:
public class MainActivity extends Activity
{
.
.
.
@Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
.
.
.
}
@Override
protected void onResume()
{
super.onResume();
IntentFilter intentFilter = new IntentFilter();
intentFilter.addAction(WifiManager.SUPPLICANT_CONNECTION_CHANGE_ACTION);
registerReceiver(broadcastReceiver, intentFilter);
}
@Override
protected void onPause()
{
super.onPause();
unregisterReceiver(broadcastReceiver);
}
private final BroadcastReceiver broadcastReceiver = new BroadcastReceiver()
{
@Override
public void onReceive(Context context, Intent intent)
{
final String action = intent.getAction();
if (action.equals(WifiManager.SUPPLICANT_CONNECTION_CHANGE_ACTION))
{
if (intent.getBooleanExtra(WifiManager.EXTRA_SUPPLICANT_CONNECTED, false))
{
// wifi is enabled
}
else
{
// wifi is disabled
}
}
}
};
}
对于所有喜欢CONNECTIVITY_CHANGE广播的人,请注意,当应用程序在 Android O 中处于后台时,它不再被触发。
https://developer.android.com/about/versions/o/background.html
您可以使用带过滤器的广播
<receiver
android:name=".receivers.ConnectionType"
android:enabled="true"
android:exported="true">
<intent-filter>
<action android:name="android.net.wifi.WIFI_STATE_CHANGED" />
</intent-filter>
</receiver>
之后,您可以像这样收听返回的值
@Override
public void onReceive(Context context, Intent intent) {
int wifiState = intent.getIntExtra(WifiManager.EXTRA_WIFI_STATE, WifiManager.WIFI_STATE_UNKNOWN);
if(wifiState==WifiManager.WIFI_STATE_ENABLED){
Toast.makeText(context, "WIFI on", Toast.LENGTH_SHORT).show();
}else if(wifiState==WifiManager.WIFI_STATE_DISABLED) {
Toast.makeText(context, "WIFI OFF", Toast.LENGTH_SHORT).show();
}
}
每次启用或禁用 WIFI 时都会触发