首先安卓手机要支持蓝牙5.0

在未设置搜索广播类型时,是无法搜索到扩展广播的

val scanSettings = ScanSettings.Builder()
            .setLegacy(false)   // 可以搜索到扩展广播

        val scanSettings = ScanSettings.Builder().setScanMode(ScanSettings.SCAN_MODE_LOW_LATENCY) // 设置扫描模式.setLegacy(false)   // 可以搜索到扩展广播.setReportDelay(0) // 实时报告，0 表示无延迟.setNumOfMatches(ScanSettings.MATCH_NUM_MAX_ADVERTISEMENT) // 设置匹配数量.setCallbackType(ScanSettings.CALLBACK_TYPE_ALL_MATCHES) // 设置回调类型.build()// 创建ScanFilter实例（如果需要特定的过滤条件）val filter = ScanFilter.Builder()
//            .setServiceUuid(ParcelUuid.fromString("018efc9d-6b58-79d2-bc8f-0be0388883bb"))
//            .setServiceUuid(ParcelUuid.fromString("0000FFF3-0000-1000-8000-00805F9B34FB")).build()mBluetoothAdapter =(getSystemService(Context.BLUETOOTH_SERVICE) as BluetoothManager).adapter
//        mBluetoothAdapter.bluetoothLeScanner.startScan(scanCallback)mBluetoothAdapter.bluetoothLeScanner.startScan(listOf(filter), scanSettings, scanCallback)