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
Try
wifiManager.getConnectionInfo().getIpAddress()
这将返回0，直到设备有一个可用的连接(在我的机器上，三星SM-T280, Android 5.1.1)。
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。
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;
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;
}
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();
}
}
