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
这个问题有点老了，但我用的就是这个。要求最低api级别21也考虑到废弃的Networkinfo api。
boolean isWifiConn = false;
ConnectivityManager connMgr = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
Network network = connMgr.getActiveNetwork();
if (network == null) return false;
NetworkCapabilities capabilities = connMgr.getNetworkCapabilities(network);
if(capabilities != null && capabilities.hasTransport(NetworkCapabilities.TRANSPORT_WIFI)){
isWifiConn = true;
Toast.makeText(context,"Wifi connected Api >= "+Build.VERSION_CODES.M,Toast.LENGTH_LONG).show();
}else{
Toast.makeText(context,"Wifi not connected Api >= "+Build.VERSION_CODES.M,Toast.LENGTH_LONG).show();
}
} else {
for (Network network : connMgr.getAllNetworks()) {
NetworkInfo networkInfo = connMgr.getNetworkInfo(network);
if (networkInfo.getType() == ConnectivityManager.TYPE_WIFI && networkInfo.isConnected()) {
isWifiConn = true;
Toast.makeText(context,"Wifi connected ",Toast.LENGTH_LONG).show();
break;
}else{
Toast.makeText(context,"Wifi not connected ",Toast.LENGTH_LONG).show();
}
}
}
return isWifiConn;
其他回答
这个问题有点老了，但我用的就是这个。要求最低api级别21也考虑到废弃的Networkinfo api。
boolean isWifiConn = false;
ConnectivityManager connMgr = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
Network network = connMgr.getActiveNetwork();
if (network == null) return false;
NetworkCapabilities capabilities = connMgr.getNetworkCapabilities(network);
if(capabilities != null && capabilities.hasTransport(NetworkCapabilities.TRANSPORT_WIFI)){
isWifiConn = true;
Toast.makeText(context,"Wifi connected Api >= "+Build.VERSION_CODES.M,Toast.LENGTH_LONG).show();
}else{
Toast.makeText(context,"Wifi not connected Api >= "+Build.VERSION_CODES.M,Toast.LENGTH_LONG).show();
}
} else {
for (Network network : connMgr.getAllNetworks()) {
NetworkInfo networkInfo = connMgr.getNetworkInfo(network);
if (networkInfo.getType() == ConnectivityManager.TYPE_WIFI && networkInfo.isConnected()) {
isWifiConn = true;
Toast.makeText(context,"Wifi connected ",Toast.LENGTH_LONG).show();
break;
}else{
Toast.makeText(context,"Wifi not connected ",Toast.LENGTH_LONG).show();
}
}
}
return isWifiConn;
这适用于最新版本的android:
fun getConnectionType(context: Context): ConnectivityType {
var result = NONE
val cm = context.getSystemService(Context.CONNECTIVITY_SERVICE) as ConnectivityManager?
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
if (cm != null) {
val capabilities = cm.getNetworkCapabilities(cm.activeNetwork)
if (capabilities != null) {
when {
capabilities.hasTransport(NetworkCapabilities.TRANSPORT_WIFI) -> {
result = WIFI
}
capabilities.hasTransport(NetworkCapabilities.TRANSPORT_CELLULAR) -> {
result = MOBILE_DATA
}
capabilities.hasTransport(NetworkCapabilities.TRANSPORT_VPN) -> {
result = VPN
}
}
}
}
} else {
if (cm != null) {
val activeNetwork = cm.activeNetworkInfo
if (activeNetwork != null) {
// connected to the internet
when (activeNetwork.type) {
ConnectivityManager.TYPE_WIFI -> {
result = WIFI
}
ConnectivityManager.TYPE_MOBILE -> {
result = MOBILE_DATA
}
ConnectivityManager.TYPE_VPN -> {
result = VPN
}
}
}
}
}
return result
}
enum class ConnectivityType {
NONE,
MOBILE_DATA,
WIFI,
VPN,
}
在清单中:
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
虽然Jason的回答是正确的，但现在getNetWorkInfo (int)是一个不推荐使用的方法。所以，下一个函数将是一个很好的选择:
public static boolean isWifiAvailable (Context context)
{
boolean br = false;
ConnectivityManager cm = null;
NetworkInfo ni = null;
cm = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
ni = cm.getActiveNetworkInfo();
br = ((null != ni) && (ni.isConnected()) && (ni.getType() == ConnectivityManager.TYPE_WIFI));
return br;
}
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.
下面是我在我的应用程序中使用的实用方法:
public static boolean isDeviceOnWifi(final Context context) {
ConnectivityManager connManager = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo mWifi = connManager.getNetworkInfo(ConnectivityManager.TYPE_WIFI);
return mWifi != null && mWifi.isConnectedOrConnecting();
}
