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
使用WifiManager你可以做到:
WifiManager wifi = (WifiManager) getSystemService (Context.WIFI_SERVICE);
if (wifi.getConnectionInfo().getNetworkId() != -1) {/* connected */}
方法getNeworkId只有在没有连接到网络时才返回-1;
其他回答
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" />
你可以打开WIFI，如果它没有被激活如下 1. 查看@Jason Knight回复的WIFI状态 2. 如果没有激活，请激活它 不要忘记在manifest文件中添加WIFI权限
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
您的Java类应该是这样的
public class TestApp extends Activity {
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
//check WIFI activation
ConnectivityManager connManager = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo mWifi = connManager.getNetworkInfo(ConnectivityManager.TYPE_WIFI);
if (mWifi.isConnected() == false) {
showWIFIDisabledAlertToUser();
}
else {
Toast.makeText(this, "WIFI is Enabled in your devide", Toast.LENGTH_SHORT).show();
}
}
private void showWIFIDisabledAlertToUser(){
AlertDialog.Builder alertDialogBuilder = new AlertDialog.Builder(this);
alertDialogBuilder.setMessage("WIFI is disabled in your device. Would you like to enable it?")
.setCancelable(false)
.setPositiveButton("Goto Settings Page To Enable WIFI",
new DialogInterface.OnClickListener(){
public void onClick(DialogInterface dialog, int id){
Intent callGPSSettingIntent = new Intent(
Settings.ACTION_WIFI_SETTINGS);
startActivity(callGPSSettingIntent);
}
});
alertDialogBuilder.setNegativeButton("Cancel",
new DialogInterface.OnClickListener(){
public void onClick(DialogInterface dialog, int id){
dialog.cancel();
}
});
AlertDialog alert = alertDialogBuilder.create();
alert.show();
}
}
val wifi = context!!.applicationContext.getSystemService(Context.WIFI_SERVICE) as WifiManager?
if (wifi!!.isWifiEnabled)
//do action here
else
//do action here
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
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。
