很多人已经问过这个问题,但对他们有用的解决方案对我来说并不适用。我在Android 8.1和Android 9.0上测试过,无法获取到SSID的名称。
用于获取 WiFi 状态更改的广播接收器:
private final BroadcastReceiver mReceiver = new BroadcastReceiver() {
public void onReceive(Context context, Intent intent) {
String action = intent.getAction();
if(intent.getAction().equals(WifiManager.WIFI_STATE_CHANGED_ACTION) ||
intent.getAction().equals(ConnectivityManager.CONNECTIVITY_ACTION) ||
intent.getAction().equals(WifiManager.SUPPLICANT_STATE_CHANGED_ACTION) ||
intent.getAction().equals(WifiManager.SUPPLICANT_CONNECTION_CHANGE_ACTION) ||
intent.getAction().equals(WifiManager.NETWORK_STATE_CHANGED_ACTION)) {
setWifiIndicator();
}
}
};
接收者已注册onCreate
并在 onDestroy
中未注册,我认为这是正确的,并且在调用接收器时我看到了日志行。
在onCreate
:
IntentFilter intentFilter = new IntentFilter();
intentFilter.addAction(ScannerService.ACTION_READ_SCANNER);
intentFilter.addAction(WifiManager.WIFI_STATE_CHANGED_ACTION);
intentFilter.addAction(WifiManager.SUPPLICANT_CONNECTION_CHANGE_ACTION);
intentFilter.addAction(WifiManager.NETWORK_STATE_CHANGED_ACTION);
intentFilter.addAction(ConnectivityManager.CONNECTIVITY_ACTION);
intentFilter.addAction(WifiManager.SUPPLICANT_STATE_CHANGED_ACTION);
registerReceiver(mReceiver, intentFilter);
setWifiIndicator();
setWifiIndicator
是这样实现的:
private void setWifiIndicator() {
ConnectivityManager connMgr = (ConnectivityManager)getSystemService(Context.CONNECTIVITY_SERVICE);
//getApplicationContext solves memory leak issues prior to Android N (must use Application Context to get wifi system service.
WifiManager wifiMgr = (WifiManager)getApplicationContext().getSystemService(Context.WIFI_SERVICE);
ImageView wifiIndicator = (ImageView)findViewById(R.id.wifi_indicator);
TextView wifiSSID = (TextView)findViewById(R.id.wifi_ssid);
try {
if (wifiMgr != null) {
if (wifiMgr.isWifiEnabled()) {
//wifi is enabled. toggle on wifi indicator.
wifiIndicator.setImageResource(R.drawable.wifi_indicator);
String ssid = wifiMgr.getConnectionInfo().getSSID();
if (ssid != null) {
Log.v(this.getClass().getSimpleName(), "SSID: " + ssid + " Supplicant State: " + info.getSupplicantState());
wifiSSID.setText(ssid);
}
} else {
//wifi is disabled. toggle off wifi indicator.
wifiSSID.setText("");
//check for 3G
NetworkInfo mobileInfo = connMgr.getNetworkInfo(ConnectivityManager.TYPE_MOBILE);
if (mobileInfo != null && mobileInfo.getState().equals(NetworkInfo.State.CONNECTED)) {
wifiIndicator.setImageResource(R.drawable.cellular_indicator);
} else {
wifiIndicator.setImageResource(R.drawable.down_indicator);
}
}
} else {
//check for 3G
NetworkInfo mobileInfo = connMgr.getNetworkInfo(ConnectivityManager.TYPE_MOBILE);
if (mobileInfo != null && mobileInfo.getState().equals(NetworkInfo.State.CONNECTED)) {
wifiIndicator.setImageResource(R.drawable.cellular_indicator);
} else {
wifiIndicator.setImageResource(R.drawable.down_indicator);
}
}
} catch(Exception e) {
//catching anything thrown in this block just so it doesn't crash the program unnecessarily
e.printStackTrace();
}
}
我的应用程序已经获得了 ACCESS_COARSE_LOCATION
的许可但我还添加了 ACCESS_FINE_LOCATION
万一。 getSSID()
直到回来<unknown ssid>
.
<uses-permission android:name="android.permission.INTERNET"/>
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<uses-permission android:name="android.permission.CHANGE_WIFI_STATE" />
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-permission android:name="android.permission.BLUETOOTH" />
<uses-permission android:name="android.permission.BLUETOOTH_ADMIN" />
<uses-permission android:name="android.permission.CAMERA" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.GET_TASKS" />
可能跟编译目标SDK有关?我在这里真的一无所知。
渐变文件:
应用插件:'com.android.application'
android {
compileSdkVersion 28
defaultConfig {
applicationId "com.noneofyour.business"
minSdkVersion 15
targetSdkVersion 28
versionCode 59
versionName "1.44"
testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
}
buildTypes {
release {
minifyEnabled false
proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
}
}
}
dependencies {
implementation fileTree(include: ['*.jar'], dir: 'libs')
implementation 'com.android.support:appcompat-v7:28.0.0'
testImplementation 'junit:junit:4.12'
androidTestImplementation 'com.android.support.test:runner:1.0.2'
androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2'
implementation files('libs/android.jar')
}
最佳答案
无线网络权限
Android 8.0 和 Android 8.1:
成功调用 WifiManager.getScanResults() 需要以下任一权限:
• ACCESS_FINE_LOCATION • ACCESS_COARSE_LOCATION • CHANGE_WIFI_STATE
如果调用应用程序没有任何这些权限,调用将失败并出现 SecurityException。
安卓 9:
成功调用 WifiManager.startScan() 需要满足以下所有条件:
• 您的应用具有 ACCESS_FINE_LOCATION 或 ACCESS_COARSE_LOCATION 权限。 • 您的应用程序具有CHANGE_WIFI_STATE 权限。 • 设备上启用了位置服务(在“设置”>“位置”下)。
Android 10(API 级别 29)及更高版本:
成功调用 WifiManager.startScan() 需要满足以下所有条件:
• 如果您的应用以 Android 10(API 级别 29)SDK 或更高版本为目标平台,则您的应用具有 ACCESS_FINE_LOCATION 权限。
• 如果您的应用的目标 SDK 低于 Android 10(API 级别 29),则您的应用具有 ACCESS_COARSE_LOCATION 或 ACCESS_FINE_LOCATION 权限。
• 您的应用具有 CHANGE_WIFI_STATE 权限。
• 设备上启用了位置服务(在“设置”>“位置”下)。
并Request User级权限实现
有关详细信息,请参阅此链接:https://developer.android.com/guide/topics/connectivity/wifi-scan#wifi-scan-permissions
XAMARIN FORMS 代码更改:
if (Android.OS.Build.VERSION.SdkInt >= Android.OS.BuildVersionCodes.O){ status = await CrossPermissions.Current.CheckPermissionStatusAsync(Permission.Location); if (status != PermissionStatus.Granted) { var results = await CrossPermissions.Current.RequestPermissionsAsync(new[] { Permission.Location }); status = results[Permission.Location]; } }
关于java - WiFi getSSID() 总是返回 "<unknown ssid>",我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/54736828/