android ble链接

您好！关于 Android BLE 连接，可以按照以下步骤进行：

1. 获取 BluetoothAdapter 对象，并检查设备是否支持 BLE。

final BluetoothManager bluetoothManager = (BluetoothManager) getSystemService(Context.BLUETOOTH_SERVICE);
BluetoothAdapter bluetoothAdapter = bluetoothManager.getAdapter();

// 检查设备是否支持 BLE
if (bluetoothAdapter == null || !getPackageManager().hasSystemFeature(PackageManager.FEATURE_BLUETOOTH_LE)) {
    Toast.makeText(this, "设备不支持BLE", Toast.LENGTH_SHORT).show();
    finish();
    return;
}

2. 扫描设备，获取 BluetoothDevice 对象。

// 构建扫描过滤条件
ScanFilter scanFilter = new ScanFilter.Builder()
        .setServiceUuid(ParcelUuid.fromString(SERVICE_UUID))
        .build();
ScanSettings scanSettings = new ScanSettings.Builder()
        .setScanMode(ScanSettings.SCAN_MODE_LOW_LATENCY)
        .build();

// 开始扫描
bluetoothAdapter.getBluetoothLeScanner().startScan(Collections.singletonList(scanFilter), scanSettings, scanCallback);

// 扫描回调
private ScanCallback scanCallback = new ScanCallback() {
    @Override
    public void onScanResult(int callbackType, ScanResult result) {
        BluetoothDevice device = result.getDevice();
        // 连接设备
        connectDevice(device);
    }
};

3. 连接设备，获取 BluetoothGatt 对象。

private BluetoothGatt bluetoothGatt;

private void connectDevice(BluetoothDevice device) {
    bluetoothGatt = device.connectGatt(this, false, gattCallback);
}

// GATT 连接回调
private BluetoothGattCallback gattCallback = new BluetoothGattCallback() {
    @Override
    public void onConnectionStateChange(BluetoothGatt gatt, int status, int newState) {
        if (newState == BluetoothProfile.STATE_CONNECTED) {
            // 连接成功，开始发现服务
            bluetoothGatt.discoverServices();
        } else if (newState == BluetoothProfile.STATE_DISCONNECTED) {
            // 连接断开
            bluetoothGatt.close();
        }
    }

    @Override
    public void onServicesDiscovered(BluetoothGatt gatt, int status) {
        // 服务发现完成
        if (status == BluetoothGatt.GATT_SUCCESS) {
            // 获取指定 UUID 的服务和特征
            BluetoothGattService service = bluetoothGatt.getService(UUID.fromString(SERVICE_UUID));
            BluetoothGattCharacteristic characteristic = service.getCharacteristic(UUID.fromString(CHARACTERISTIC_UUID));
            // 读写特征值等操作
            ...
        }
    }
};

以上是 Android BLE 连接的基本流程，具体的操作可以根据实际需求进行调整。