android获取usb权限
时间: 2023-07-30 12:09:37 浏览: 51
要在 Android 应用程序中访问 USB 设备,您需要获取 USB 访问权限。以下是获取 Android USB 访问权限的步骤:
1. 在 AndroidManifest.xml 文件中添加以下权限:
```
<uses-permission android:name="android.permission.USB_PERMISSION" />
```
2. 在您的 Activity 中注册 BroadcastReceiver:
```
private final BroadcastReceiver usbReceiver = new BroadcastReceiver() {
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){
// 已获得USB访问权限,可以进行相应操作
}
}
else {
Log.d(TAG, "permission denied for device " + device);
}
}
}
}
};
```
3. 在您的 Activity 中获取 UsbManager 对象并请求 USB 访问权限:
```
private UsbManager usbManager;
private UsbDevice device;
PendingIntent pendingIntent = PendingIntent.getBroadcast(this, 0, new Intent(ACTION_USB_PERMISSION), 0);
IntentFilter filter = new IntentFilter(ACTION_USB_PERMISSION);
registerReceiver(usbReceiver, filter);
usbManager = (UsbManager) getSystemService(Context.USB_SERVICE);
HashMap<String, UsbDevice> deviceList = usbManager.getDeviceList();
Iterator<UsbDevice> deviceIterator = deviceList.values().iterator();
while (deviceIterator.hasNext()) {
device = deviceIterator.next();
usbManager.requestPermission(device, pendingIntent);
}
```
以上代码将请求 USB 访问权限并在用户授权时通过 BroadcastReceiver 接收通知。当用户授权您的应用程序访问 USB 设备时,您将能够使用 UsbDevice 对象执行您需要的操作。