android

android usbmanager如何设置参数

小樊
90
2024-11-23 10:24:23
栏目: 编程语言

在Android中,UsbManager是用于管理和控制USB设备的类。要设置UsbManager的参数,您需要执行以下步骤:

  1. 获取UsbManager实例:
UsbManager usbManager = (UsbManager) getSystemService(Context.USB_SERVICE);
  1. 检查设备是否已连接:
HashMap<String, UsbDevice> deviceList = usbManager.getDeviceList();
Iterator<UsbDevice> deviceIterator = deviceList.values().iterator();
while (deviceIterator.hasNext()) {
    UsbDevice device = deviceIterator.next();
    if (device.getVendorId() == YOUR_VENDOR_ID && device.getProductId() == YOUR_PRODUCT_ID) {
        // 设备已连接,可以进行后续操作
    }
}
  1. 打开设备:
UsbDeviceConnection connection = usbManager.openDevice(device);
  1. 设置配置:
UsbInterface intf = device.getInterface(YOUR_INTERFACE_INDEX);
UsbEndpoint endpointIn = null;
UsbEndpoint endpointOut = null;
for (int i = 0; i < intf.getEndpointCount(); i++) {
    UsbEndpoint endpoint = intf.getEndpoint(i);
    if (endpoint.getDirection() == UsbConstants.USB_DIR_IN) {
        endpointIn = endpoint;
    } else if (endpoint.getDirection() == UsbConstants.USB_DIR_OUT) {
        endpointOut = endpoint;
    }
}
if (endpointIn != null && endpointOut != null) {
    // 设置配置
    connection.claimInterface(intf, true);
} else {
    // 无法设置配置
}
  1. 设置权限:

在AndroidManifest.xml中添加以下权限:

<uses-feature android:name="android.hardware.usb.host" />
<uses-permission android:name="android.permission.USB_PERMISSION" />

在代码中检查并请求权限(如果需要):

String deviceName = device.getDeviceName();
UsbDeviceConnection connection = usbManager.openDevice(device);
if (connection != null) {
    HashMap<String, UsbDevice> deviceList = usbManager.getDeviceList();
    Iterator<UsbDevice> deviceIterator = deviceList.values().iterator();
    while (deviceIterator.hasNext()) {
        UsbDevice device = deviceIterator.next();
        if (device.getVendorId() == YOUR_VENDOR_ID && device.getProductId() == YOUR_PRODUCT_ID) {
            PendingIntent permissionIntent = PendingIntent.getBroadcast(this, 0, new Intent("com.example.USB_PERMISSION"), 0);
            usbManager.requestPermission(device, permissionIntent);
            break;
        }
    }
}

在广播接收器中处理权限请求结果:

public class UsbReceiver extends BroadcastReceiver {
    @Override
    public void onReceive(Context context, Intent intent) {
        String action = intent.getAction();
        if (ACTION_USB_PERMISSION.equals(action)) {
            synchronized (this) {
                UsbDevice device = (UsbDevice) intent.getParcelableExtra(UsbManager.EXTRA_DEVICE);
                if (intent.getBooleanExtra(UsbManager.EXTRA_PERMISSION_GRANTED, false)) {
                    if (device != null) {
                        // 权限被授予,可以进行后续操作
                    }
                } else {
                    // 权限被拒绝
                }
            }
        }
    }
}
  1. 关闭设备连接:
connection.close();

以上示例展示了如何使用UsbManager设置参数。请注意,您需要根据实际情况替换YOUR_VENDOR_IDYOUR_PRODUCT_IDYOUR_INTERFACE_INDEX

0
看了该问题的人还看了