Is it possible to identify the USB communication mode programatically?

Question

Is there a way to programatically identify the currently USB working mode?

I mean, some function that would return either if the device is at Host, Device or Accessory mode.

Answer 1

Not the best answer, but once you have a UsbManager you might be able to figure it out. Usually this UsbManager is created using a Context I believe, but it looks like you are switching modes so you hopefully can get a UsbManager instance, m in this case:

UsbManager m = createManagerSomehow

For accessory mode, this only has one callback. If this returns one then you know it is Accessory.

m.getAccessoryList()

So I'm thinking somehting like this might work:

if(m.getAccessoryList().size() > 0)
    accessoryMode = true;

And for Host, if you have a UsbDevice device, or String deviceName you could use the same UsbManager m function to see if it contains that device.

if(m.getDeviceList().containsValue(device))
    hostMode = true;

or

if(m.getDeviceList().containsKey(deviceName))
    hostMode = true;

and I don't know about what Device is, but if none of the above are true then you know it is just a Device. You don't really need this boolean variable below, because you have the other two. It's just here to help with my explanation via state logic.

if(!hostMode && !accessoryMode)
    deviceMode = true

Hope this helps. Check out UsbManager for more documentation and just search the page for Host and Accessory.

http://developer.android.com/reference/android/hardware/usb/UsbManager.html

NOTE: I am a little confused when you say you switch the modes in your comment. It conflicts with the Accessory call I make above and might not work, but what I would do then (if you don't need deviceMode) then just check if the usb device is a HOST mode and if not you know it is in application mode...