我不希望我的用户尝试下载任何东西，除非他们连接了Wi-Fi。然而，我似乎只能判断是否启用了Wi-Fi，但他们仍然可能有3G连接。
android.net.wifi.WifiManager m = (WifiManager) getSystemService(WIFI_SERVICE);
android.net.wifi.SupplicantState s = m.getConnectionInfo().getSupplicantState();
NetworkInfo.DetailedState state = WifiInfo.getDetailedStateOf(s);
if (state != NetworkInfo.DetailedState.CONNECTED) {
return false;
}
然而，这种状态并不是我所期望的。即使Wi-Fi是连接的，我得到OBTAINING_IPADDR作为状态。
当前回答
从API级别29开始，NetworkInfo类以及相关的访问方法(如connectivitymanager# getNetworkInfo()和connectivitymanager# getActiveNetworkInfo())都已弃用。
文档现在建议人们使用ConnectivityManager。NetworkCallback API用于异步回调监控，或使用connectivitymanager# getNetworkCapabilities或connectivitymanager# getLinkProperties来同步访问网络信息
调用者应该使用ConnectivityManager。NetworkCallback API来了解连接变化，或切换到使用connectivitymanager# getNetworkCapabilities或connectivitymanager# getLinkProperties来同步获取信息。
要检查是否连接了WiFi，下面是我使用的代码:
科特林：
val connMgr = applicationContext.getSystemService(Context.CONNECTIVITY_SERVICE) as ConnectivityManager?
connMgr?: return false
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
val network: Network = connMgr.activeNetwork ?: return false
val capabilities = connMgr.getNetworkCapabilities(network)
return capabilities != null && capabilities.hasTransport(NetworkCapabilities.TRANSPORT_WIFI)
} else {
val networkInfo = connMgr.activeNetworkInfo ?: return false
return networkInfo.isConnected && networkInfo.type == ConnectivityManager.TYPE_WIFI
}
Java:
ConnectivityManager connMgr = (ConnectivityManager) getApplicationContext().getSystemService(Context.CONNECTIVITY_SERVICE);
if (connMgr == null) {
return false;
}
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
Network network = connMgr.getActiveNetwork();
if (network == null) return false;
NetworkCapabilities capabilities = connMgr.getNetworkCapabilities(network);
return capabilities != null && capabilities.hasTransport(NetworkCapabilities.TRANSPORT_WIFI);
} else {
NetworkInfo networkInfo = connMgr.getActiveNetworkInfo();
return networkInfo.isConnected() && networkInfo.getType() == ConnectivityManager.TYPE_WIFI;
}
记住还要向Manifest文件添加ACCESS_NETWORK_STATE权限。
其他回答
您应该能够使用ConnectivityManager来获取Wi-Fi适配器的状态。从那里你可以检查它是否连接，甚至可用。
ConnectivityManager connManager = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo mWifi = connManager.getNetworkInfo(ConnectivityManager.TYPE_WIFI);
if (mWifi.isConnected()) {
// Do whatever
}
注意:应该注意(对于这里的n00bies)，您需要添加
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
到你的
AndroidManifest.xml来工作。
注2:公共NetworkInfo getNetworkInfo (int networkType)现在已弃用:
此方法在API级别23中已弃用。这个方法没有 支持多个相同类型的网络连接。使用 getAllNetworks()和getNetworkInfo(android.net.Network)代替。
注3:public static final int TYPE_WIFI现在已弃用:
此常量在API级别28中已弃用。 应用程序应该使用networkcapabilities . hatransporsport (int)或requestNetwork(NetworkRequest, NetworkCallback)来请求一个合适的网络。对于支持的传输。
在新版Android中
private void getWifiInfo(Context context) {
ConnectivityManager connManager = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
Network[] networks = connManager.getAllNetworks();
if(networks == null || networks.length == 0)
return;
for( int i = 0; i < networks.length; i++) {
Network ntk = networks[i];
NetworkInfo ntkInfo = connManager.getNetworkInfo(ntk);
if (ntkInfo.getType() == ConnectivityManager.TYPE_WIFI && ntkInfo.isConnected() ) {
final WifiManager wifiManager = (WifiManager) context.getSystemService(Context.WIFI_SERVICE);
final WifiInfo connectionInfo = wifiManager.getConnectionInfo();
if (connectionInfo != null) {
// add some code here
}
}
}
}
还要加上前提
ConnectivityManager manager = (ConnectivityManager) getSystemService(CONNECTIVITY_SERVICE);
boolean is3g = manager.getNetworkInfo(
ConnectivityManager.TYPE_MOBILE).isConnectedOrConnecting();
boolean isWifi = manager.getNetworkInfo(
ConnectivityManager.TYPE_WIFI).isConnectedOrConnecting();
Log.v("", is3g + " ConnectivityManager Test " + isWifi);
if (!is3g && !isWifi) {
Toast.makeText(
getApplicationContext(),
"Please make sure, your network connection is ON ",
Toast.LENGTH_LONG).show();
}
else {
// Put your function() to go further;
}
添加到JAVA:
public boolean CheckWifiConnection() {
ConnectivityManager conMgr = (ConnectivityManager) getSystemService (Context.CONNECTIVITY_SERVICE);
if (conMgr.getActiveNetworkInfo() != null
&& conMgr.getActiveNetworkInfo().isAvailable()
&& conMgr.getActiveNetworkInfo().isConnected()) {
return true;
} else {
return false;
}
}
在Manifest文件中添加以下权限:
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
我简单地使用以下方法:
SupplicantState supState;
wifiManager = (WifiManager) getSystemService(Context.WIFI_SERVICE);
WifiInfo wifiInfo = wifiManager.getConnectionInfo();
supState = wifiInfo.getSupplicantState();
它将在调用getSupplicantState()时返回这些状态之一;
ASSOCIATED - Association completed. ASSOCIATING - Trying to associate with an access point. COMPLETED - All authentication completed. DISCONNECTED - This state indicates that client is not associated, but is likely to start looking for an access point. DORMANT - An Android-added state that is reported when a client issues an explicit DISCONNECT command. FOUR_WAY_HANDSHAKE - WPA 4-Way Key Handshake in progress. GROUP_HANDSHAKE - WPA Group Key Handshake in progress. INACTIVE - Inactive state. INVALID - A pseudo-state that should normally never be seen. SCANNING - Scanning for a network. UNINITIALIZED - No connection.
