我尝试在后台模式下扫描附近的蓝牙设备，但它在 Android 11+ 等某些设备上不起作用。
这是我的示例代码，在前台工作得很好
//授予所有权限
<uses-permission android:name="android.permission.FOREGROUND_SERVICE" />
<uses-permission android:name="android.permission.ACCESS_BACKGROUND_LOCATION" />
<!--BLUETOOTH PERMISSION-->
<uses-permission android:name="android.permission.BLUETOOTH" />
<uses-permission android:name="android.permission.BLUETOOTH_ADMIN" />
<!-- Needed only if your app looks for Bluetooth devices.
If your app doesn't use Bluetooth scan results to derive physical
location information, you can strongly assert that your app
doesn't derive physical location. -->
<uses-permission android:name="android.permission.BLUETOOTH_SCAN" />
<!-- Needed only if your app makes the device discoverable to Bluetooth
devices. -->
<uses-permission android:name="android.permission.BLUETOOTH_ADVERTISE" />
<!-- Needed only if your app communicates with already-paired Bluetooth
devices. -->
<uses-permission android:name="android.permission.BLUETOOTH_CONNECT" />
<!--bibo01 : hardware option-->
<uses-feature android:name="android.hardware.bluetooth" android:required="false"/>
<uses-feature android:name="android.hardware.bluetooth_le" android:required="false"/>
// 用于扫描 api 版本高于 21 的 Ble 设备
private var settings: ScanSettings? = null
private val scanFilters = java.util.ArrayList<ScanFilter>()
private var mLEScanner: BluetoothLeScanner? = null
private var adapter: BluetoothAdapter? = null
val adapterBlu = applicationContextNew.getSystemService(Context.BLUETOOTH_SERVICE) as BluetoothManager
adapter = adapterBlu.adapter
mLEScanner = adapter!!.bluetoothLeScanner
settings = ScanSettings.Builder()
//.setScanMode(ScanSettings.SCAN_MODE_LOW_POWER)
.build()
//scan specified devices only with ScanFilter
val scanFilter = ScanFilter.Builder()
//.setDeviceName("BIBO 1")
.build()
scanFilters.add(scanFilter)
mLEScanner = adapter!!.bluetoothLeScanner
settings = ScanSettings.Builder()
.build()
//scan specified devices only with ScanFilter
val scanFilter = ScanFilter.Builder()
.build()
scanFilters.add(scanFilter)
// scan:
mLEScanner!!.startScan(scanFilters, settings, highScanCallback)
//high Scan callback
private val highScanCallbackClackmass =
object : ScanCallback() {
override fun onScanResult(callbackType: Int, result: ScanResult) {
if (result.device.name != null && result.device.address != null){
if ("BIBO 1" == result.device.name.toString()) {
//globalDeviceAddress = result.device.address.toString()
}
}
}
}
还尝试了屏幕唤醒解决方案：（在 android 10 以下工作）
val pm: PowerManager = getSystemService(POWER_SERVICE) as PowerManager
val isScreenOn: Boolean = pm.isInteractive // check if screen is on
if (!isScreenOn) {
val wl: PowerManager.WakeLock = pm.newWakeLock(PowerManager.SCREEN_DIM_WAKE_LOCK or PowerManager.ACQUIRE_CAUSES_WAKEUP, "myApp:notificationLock")
wl.acquire(9000) //set your time in milliseconds
}
