Substitute for tkinter.dooneevent

Question

I am porting a program (VMD, Visual Molecular Dynamics), which is written in C++ and has both Python and TCL interpreters embedded, to Python 3.x. Most of its UI is hard coded u

Answer 1

It looks like this is equivalent:

root = tkinter.Tk()

# Here's your event handler. Put it in a loop somewhere.
root.tk.dooneevent(tkinter._tkinter.DONT_WAIT)
# I don't know if it's possible to access this method without a Tk object.

Now, I don't know how exactly to convert this into your code- do you have a root Tk object with which you can access dooneevent? I'm not at all familiar with python 2 tkinter so I don't know exactly how evenly my code maps to yours. However, I discovered this when I was doing something very similar to you- trying to integrate the tkinter event loop into the asyncio event loop. I was able to create a coroutine that calls this method in a loop, yielding each time (and sleeping occasionally), so that the GUI remains responsive without blocking the asyncio event loop with tkinter._tkinter.create().

@asyncio.coroutine
def update_root(root):
    while root.tk.dooneevent(tkinter._tkinter.DONT_WAIT):
        yield

EDIT: I just read your comment about not having a widget. I know that the root.tk object is a tkinter._tkinter.TkappType instance created by calling tkinter._tkinter.create, and I don't think it's global. I'm pretty sure it's the core Tcl interpreter. You might be able to create your own by calling create. While it isn't documented, you can look at its usage in tkinter.Tk.__init__