找不到方法android.bluetooth.le.BluetoothLeScanner.startScan

Question

来自宏碁平板电脑的错误日志，宏碁B1-810android 4.4.4我正在测试小的BLE应用程序，我得到了这个日志“找不到方法android.bluetooth.le.BluetoothLeScanner.startScan "，我很困惑，因为BLE是在API18 (4.3)中引入的，这里我使用的是安卓4.4.4，但是”找不到方法android.bluetooth.le.BluetoothLeScanner.startScan“。它显示在日志中。

Answer 1

使用BluetoothAdapter.startLeScan()在21版本以下的应用编程接口中添加了BluetoothLeScanner

private void startBluetoothLeScan() {
    BluetoothManager bluetoothManager = (BluetoothManager) getSystemService(Context.BLUETOOTH_SERVICE);
    BluetoothAdapter bluetoothAdapter = bluetoothManager.getAdapter();
    if (Build.VERSION.SDK_INT < 21) {
        bluetoothAdapter.startLeScan(new BluetoothAdapter.LeScanCallback() {
            @Override
            public void onLeScan(BluetoothDevice device, int rssi, byte[] scanRecord) {

            }
        });
    } else {
        BluetoothLeScanner bluetoothLeScanner = bluetoothAdapter.getBluetoothLeScanner();
        ScanSettings scanSettings = new ScanSettings.Builder().setScanMode(ScanSettings.SCAN_MODE_LOW_LATENCY)
                .build();
        List<ScanFilter> scanFilters = new ArrayList<>();
        bluetoothLeScanner.startScan(scanFilters, scanSettings, new ScanCallback() {
            @Override
            public void onScanResult(int callbackType, ScanResult result) {
            }

            @Override
            public void onBatchScanResults(List<ScanResult> results) {
            }

            @Override
            public void onScanFailed(int errorCode) {
                super.onScanFailed(errorCode);
            }
        });
    }
}

有关详细信息，请参阅Bluetooth Low Energy文档