getDeviceList（）总是空 [英] getDeviceList() always empty

问题描述

我试图用一个Arduino板连同我ODYS新X8平板，但现在看来，该UsbManager无法识别该设备没有问题。连接了的Arduino到片剂经由OTG适配器，以使药片将工作在主机模式下，所述的Arduino被成功接收电力从装置。 我获取可用的USB-设备列表上的平板电脑如下：

I'm trying to use an Arduino Board along with my Odys Neo x8 tablet but it seems, that the UsbManager doesn't recognize the device alright. I connected the arduino to the tablet via an OTG-adapter so that the tablet will work in host mode, the Arduino is successfully receiving power from the device. I'm fetching the list of available USB-devices on the tablet as follows:

sUsbController = new UsbController(this, mConnectionHandler, 0, 0);
        HashMap<String, UsbDevice> devlist = sUsbController.mUsbManager.getDeviceList();
        TextView t = ((TextView)findViewById(R.id.textView));
        t.setText("Found " + Integer.toString(devlist.size()) + " devices");

和类UsbController里面：

And inside the class UsbController:

mUsbManager = (UsbManager) mApplicationContext
            .getSystemService(Context.USB_SERVICE);

不过遗憾的是，该列表是空的，即使我使用的VID和PID（两个零）开始过滤。 如何解决这个问题有什么建议？

But unfortunately, the list remains empty, even if i start filtering using the VID and the PID (the two zeros). Any suggestions on how to fix this?

推荐答案

我使用了下列code的工作很细的键盘，鼠标和大容量存储设备与PANDABOARD连接，

I have used the following code which works very fine with keyboard, mouse and Mass Storage device to connect with Pandaboard,

  UsbManager usbManager = (UsbManager) getSystemService(USB_SERVICE);
  HashMap<String, UsbDevice> devicelist = usbManager.getDeviceList();
  Iterator<UsbDevice> deviceIterator = devicelist.values().iterator();

  while(deviceIterator.hasNext()) {
    UsbDevice usbDevice = deviceIterator.next();
    Log.i(Log_Tag, "Model     : " +usbDevice.getDeviceName());
    Log.i(Log_Tag, "Id        : " +usbDevice.getDeviceId());
  }

这应该与Arduino的了。

This should work with Arduino too.

这篇关于getDeviceList（）总是空的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！