My tkinter application has several controls, and I'd like to know when any changes occur to them so that I can update other parts of the application.
Is there anything that I can do short of writing an updater function, and looping at the end with:
root.after(0, updaterfunction)
This method has worked in the past but I'm afraid that it might be expensive if there are many things to check on.
Even if I did use this method, could I save resources by only updating items with changed variables? If so, please share how, as I'm not sure how to detect specific changes outside of the update function.
Many tkinter controls can be associated with a variable. For those you can put a trace on the variable so that some function gets called whenever the variable changes.
Example:
In the following example the callback will be called whenever the variable changes, regardless of how it is changed.
def callback(*args):
print(f"the variable has changed to '{var.get()}'")
root = tk.Tk()
var = tk.StringVar(value="one")
var.trace("w", callback)
For more information about the arguments that are passed to the callback see this answer