I am trying to get the enabled print services in Android.
Below code works fine in upto Android 6.0. But it is not working in Android 7.0
String enabledPrintServices = Settings.Secure.getString(mContext.getContentResolver(), "enabled_print_services");
In Nougat and up, for some reason you have to use "disabled_print_services" instead of "enabled_print_services" to get a list of disabled print services.
Documentation in source code is here.
If all you need is to see if your print service is enabled or disabled, then this alternative would be equally effective. Otherwise, if your wish is to list all enabled print services, then I have not found any such code that works for Android 7.0 and up.
Related
I'm developing an app that uses Nearby Connections API with basic P2P strategy. Suddenly, weirdly enough I'm not able to advertise and discover devices on my Pixel 3a with newest Android 12 and Play Services. OnFailureListeners throw these exceptions:
for discovering: 8037: unknown status code: 8037
for advertising: 8038: unknown status code: 8038
Indeed they cannot be found in docs and source code.
I also checked Google's "Rock Papers Scissors" official sample and it throws the same error codes.
Of course I reinstalled the app and restarted & updated my phone. EDIT: I also did the factory reset and it didn't help. But after I downgraded to latest Android 11 using Android Flash Tool, it started working again. Moreover, everything still works fine on Android 11, 10 and 9 using different phones.
Any ideas what causes this issue? It just worked fine for last two weeks and stopped working today. I believe it needs some deep investigation in source code (Xlythe if I may ask for your help, that would be really great).
After a while I finally managed to find a solution. It looks like Nearby Connections (all Nearbys?) have a critical bug on Android 12 that happens non-deterministically (API can work fine for few weeks then suddenly will throw these errors for another few weeks).
This bug is related to Android 12's feature change related to Bluetooth. Quoting:
Android 12 introduces the BLUETOOTH_SCAN, BLUETOOTH_ADVERTISE, and BLUETOOTH_CONNECT permissions. These permissions make it easier for apps that target Android 12 to interact with Bluetooth devices, especially for apps that don't require access to device location.
In other words, some Bluetooth permissions are now legacy and there are some new permissions that are mandatory to make the API work. And you need to handle both scenarios in your code (before and after Android 12).
So here's a quick "mapper" from error codes to Manifest's permissions:
Error code 8037 while discovering - you haven't granted permission
for BLUETOOTH_SCAN
Error code 8038 while advertising - you haven't granted permission for BLUETOOTH_ADVERTISE
Error code 8039 (that's a new one as well) while onEndpointFound - you haven't granted permission for BLUETOOTH_CONNECT
More information how to implement new permissions properly can be found in documentation.
And I'm still waiting for Google to fix it in next Nearby API update as this is a little bit of workaround. Adding proper error messages to codes might be a little work to do but I would also revise if other permissions are still required after Android 12's update.
I cant get serial on android 10 device.
I know about everything(permission, runtime permissions, I get serial only after the permission is granted) from here
android Build.GetSerial() throwing exception
My code works on all android versions, except 10
Do you have any ideas?
If you follow the official documentation here: https://developer.android.com/reference/android/os/Build.html#getSerial(), more info on Android 10 changes here
You will notice that starting from Android 10 this method is returning Build.UNKNOWN. You can't use it to uniquely identify a single device anymore
You need to switch to the "less" persistent version called Settings.Secure.ANDROID_ID
The only ways to bypass this restriction are:
Create a system app to be able to get the READ_PRIVILEGED_PHONE_STATE system permission (a normal app can't get this).
Be registered as a carrier (which requires you to have built the Android ROM)
Have a custom "work profile" to set your own policies in the device.
As you can imagine, all those options are not meant to be used by standard android app developers
Is there any way to get activities done by user from Android device like active time, inactive time, cyclic distance, steps count etc. without using “Google fit” api like M9 chip does in iPhone devices.
Somehow i found to get device activity by help of "Google APIs for Android" .Here you cannot get the proper count but can get the device activation mode.Please see below link
[https://developers.google.com/android/reference/com/google/android/gms/location/DetectedActivity]
I'm creating an android application that interfaces with the texas instruments sensortag. One of the things the app needs to do is be able to change the frequency in which the temperature is reported to the app. I am able to change it through the official TI app which is great, but I cannot seem to get it working in my app.
When viewing the official app (iOS, can't run the android one?), it shows the temperature GATT service, which contains 3 characteristics. When I inspect the characteristics discovered by my app however, it only seems to find two - the data, and the notifications. Not the interval. I have attempted to construct this characteristic myself and write it however it doesn't do anything - no error, no success, just nothing.
The steps I've taken are essentially:
bluetoothGatt.discoverServices();
...
services = bluetoothGatt.getServices();
...
BluetoothGattService service = bluetoothGatt.getService(serviceUUID);
System.out.println("Characteristic = " + service.getCharacteristic(SensorTagGatt.UUID_IRT_PERI));
The output yields null. Is there something obvious I'm missing or that I should be doing that I might not be?
EDIT:
I've installed another app onto the phone written by another developer, and using this to inspect the services and characteristics available shows that it too is unable to find it, so I'm assuming there is something wrong with the android service discovery? The official iOS app is working as expected, and showing all characteristics. Unfortunately, the official android app seems to be incompatible with the version 1.5 firmware and crashes when trying to connect but I assume it too will fail to find the characteristic.
Has anyone else run into this issue and if so been able to get around it?
I am into a new project which requires me to use a USBconnected "Webcam".
The whole fun should run on Android 4.4.
my little story was:
I try multiple apps which do this - all work on both my testing devices
adapting some NDK lib that directly uses /dev/video0. This didnt work due to read-permission that was not granted in a new File("dev/video0").canRead() check. Although my unix permissions are correct, this seems to not work due to some new check on Android 4.4. (the whole thing was suggested here: Connect Android phone to a USB Web camera )
next: discover the UsbAccessory API that supposedly easens a lot of the above.
´find no documentation or anything about how to correctly handle a webcam
I still try, but don't come further than finding no device via
usbManager.getAccessory();
I've also tried to discover devices by filtering for a USB_ATTACHED broadcast but nothing triggers.
So I am starting to ask myself how the hell do others find the devices & communicate with them to get the pictures?
Anyone has sources from which i could learn, or a tutorial or something?
Little update from my side:
- I've gotten access by using the Android USB Host API e.g. UsbDevice instead of UsbAccessory.
- I have the connection and everything setup fine, and can now send binary data to my webcam and supposedly receive.
I can now send controlCommands via connection.controlTransfer(...) or use a "UsbRequest" in order to receive data.
However, I couldn't find any documentation to "make the camera submit pictures" to me. My Endpoint is of type XFER_INT (=interrupts).
I am continuing to try sending out various commands (e.g. binary values) but haven't had any success so far.