I am trying to do make a virtual keyboard using tkinter. Is there any method that allow tkinter window focus out? For example in java we can have setFocusableWindowState(false) 
Thank you very much for your help.
I believe you can accomplish what you want with tkinter, but it's not about not getting focus. I don't think, that other GUI tools will make it any easier.
It's part of operation system, or more precisely window manager to give focus to some window, when it is clicked. So, in case of virtual keyboard:

User has focus in text editor (for example). 
User presses a button on your virtual keyboard.
OS/Window manager gives focus to your keyboard window and sends mouse click event to the GUI library (tkinter).
Here you need to identify where was the focus before your window got it, i.e. get the text editor window handler somehow.
Send the button press event to that window and return focus.
Repeat.

You'll use tkinter to draw the keyboard window and handle mouse clicks/touches on virtual keyboard keys. But you'll need to work with OS/Window manager to identify other windows by handlers and send keypress events to them. May be you will be able to prevent focus switch by working with OS/Window manager, but it's not tkinter or other GUI library functionality.
How to set tkinter window focus out?