我正在使用AlarmManager发布的PendingIntent(使用setRepeating)每隔几分钟启动WiFi扫描(使用IntentService).
在大多数设备上,在大多数情况下,没有问题.
但是,在几个设备上,我收到以下错误(无法在任何测试设备上重现错误,这是用户设备的崩溃日志)：
在大多数设备上,在大多数情况下,没有问题.
但是,在几个设备上,我收到以下错误(无法在任何测试设备上重现错误,这是用户设备的崩溃日志)：
java.lang.RuntimeException: Unable to start service com.myapp.android.service.MyService@44a9701 with Intent { act=com.myapp.android.ACTION_PERFORM_WIFI_SCAN flg=0x4 cmp=com.myapp/com.mayapp.android.service.MyService (has extras) }: java.lang.SecurityException: Permission Denial: broadcast from android asks to run as user -1 but is calling from user 0; this requires android.permission.INTERACT_ACROSS_USERS_FULL or android.permission.INTERACT_ACROSS_USERS
at android.app.ActivityThread.handleServiceArgs(ActivityThread.java:3021)
at android.app.ActivityThread.-wrap17(ActivityThread.java)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1443)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:148)
at android.app.ActivityThread.main(ActivityThread.java:5415)
at java.lang.reflect.Method.invoke(Method.java)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:725)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:615)
Caused by: java.lang.SecurityException: Permission Denial: broadcast from android asks to run as user -1 but is calling from user 0; this requires android.permission.INTERACT_ACROSS_USERS_FULL or android.permission.INTERACT_ACROSS_USERS
at android.os.Parcel.readException(Parcel.java:1599)
at android.os.Parcel.readException(Parcel.java:1552)
at android.net.wifi.IWifiManager$Stub$Proxy.startScan(IWifiManager.java:1045)
at android.net.wifi.WifiManager.startScan(WifiManager.java:1088)
...
我正在从我的应用程序创建PendingIntent,所以我看不到从WifiManager抛出的SecurityException的原因(特别是因为这很少发生).
从PendingIntent代码启动的IntentService如下：
mContext.registerReceiver(mWifiScanReceiver,new IntentFilter(
WifiManager.SCAN_RESULTS_AVAILABLE_ACTION));
boolean ok = mWifiManager.startScan();
关于什么可能导致这个的任何想法？
解决方法
这是因为android m的新应用权限.
看到上面的注释wifimanager的getScanResults()的源代码api 23-
看到上面的注释wifimanager的getScanResults()的源代码api 23-
/**
* Return the results of the latest access point scan.
* @return the list of access points found in the most recent scan. An app must hold
* {@link android.Manifest.permission#ACCESS_COARSE_LOCATION ACCESS_COARSE_LOCATION} or
* {@link android.Manifest.permission#ACCESS_FINE_LOCATION ACCESS_FINE_LOCATION} permission
* in order to get valid results.
*/
public List<ScanResult> getScanResults() {
try {
return mService.getScanResults(mContext.getOpPackageName());
} catch (RemoteException e) {
return null;
}
}
因此,您必须向用户询问运行时的权限.将这些权限放在您的清单中 –
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/> <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"/>
从api 23起,您需要访问用户位置才能使用它.我建议您只有在授予权限的情况下才会使用基于api级别的权限检查和启动意图.
像这样的东西 –
if (Build.VERSION.SDK_INT >= 23) {
int hasReadLocationPermission = checkSelfPermission(Manifest.permission.ACCESS_FINE_LOCATION);
if (hasReadLocationPermission != PackageManager.PERMISSION_GRANTED) {
if (!ActivityCompat.shouldShowRequestPermissionRationale(HomeActivity.this,Manifest.permission.ACCESS_FINE_LOCATION)) {
showMessageOKCancel("You need to allow access to GPS",new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog,int which) {
ActivityCompat.requestPermissions(HomeActivity.this,new String[]{Manifest.permission.ACCESS_FINE_LOCATION},GPS_ENABLE_REQUEST);
}
});
return;
}
ActivityCompat.requestPermissions(HomeActivity.this,GPS_ENABLE_REQUEST);
return;
}
if (locationManager != null && !locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER)) {
gotoGPSEnableScreen();
} else {
//Permissions granted and gps is on
launchService(true);
}
}
进一步检查结果 –
@Override
public void onRequestPermissionsResult(int requestCode,String[] permissions,int[] grantResults) {
switch (requestCode) {
case GPS_ENABLE_REQUEST:
if (grantResults[0] == PackageManager.PERMISSION_GRANTED) {
if (!locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER)) {
gotoGPSEnableScreen();
}
} else {
launchService(false);
}
default:
return;
}
}
更新：
android.permission.INTERACT_ACROSS_USERS_FULL是一个签名级别的权限.
只需在你的清单中添加这个android：protectionLevel =“signature”.
有关详细信息,您可以查看这一点
http://developer.android.com/guide/topics/manifest/permission-element.html
<permission android:name="android.permission.INTERACT_ACROSS_USERS_FULL" android:protectionLevel="signature"/>
