bluetooth lowenergy - GattDeviceService.FromIdAsync returns null -


the problem of windows uwp code:

var devices = await deviceinformation.findallasync(gattdeviceservice.getdeviceselectorfromuuid(new guid("00001520-1212-efde-1523-785feabcd124"))); gattdeviceservice m_service = await gattdeviceservice.fromidasync(devices[0].id);

is m_service null. ble device contains gatt service 00001520-1212-efde-1523-785feabcd124 uuid paired (the device visible in device manager no exlamation mark).

how fix it?

r. wang's can correct answer, hard , maybe impossible change package.appxmanifest correctly hand. in visual studio in solution explorer right-click on package.appxmanifest , select open. click capabilities , thick bluetooth , save packagemanifest (ctr + s). if not solution problem, need more of relevant code help.


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