modal toplevel

Author: furas

tkinter/modal-toplevel/main.py

@@ -0,0 +1,63 @@
+
+# author: Bartlomiej "furas" Burek (https://blog.furas.pl)
+# date: 2021.05.30
+#
+# title: How to get the updated entry string from a toplevel window before the tkinter main loop ends?
+# url: https://stackoverflow.com/questions/67754560/how-to-get-the-updated-entry-string-from-a-toplevel-window-before-the-tkinter-ma/67756653#67756653
+
+import tkinter as tk
+
+
+class NameInputBox:
+
+    entry_value = 'Empty String'
+    
+    def __init__(self, text):
+        
+        self.window = tk.Toplevel()
+        self.window.wm_title('Input Name.')
+
+        self.label = tk.Label(self.window, text=text)
+        self.label.pack(side='top')
+
+        self.frame = tk.Frame(self.window)
+        self.frame.pack(side='bottom')
+        
+        self.entry = tk.Entry(self.frame)
+        self.entry.pack(side='left')
+
+        self.button = tk.Button(self.frame, text="Ok", command=self.name_input_box_exit)
+        self.button.pack(side='left')
+
+    def name_input_box_exit(self):
+        self.entry_value = self.entry.get()
+        self.window.destroy()    
+
+
+class MainWindow:
+    def __init__(self):
+        self.window = tk.Tk()
+
+        self.label = tk.Label(self.window)
+        self.label.pack()
+        
+        self.button = tk.Button(self.window, text='Name', command=self.ask_name)
+        self.button.pack()
+
+        # the only mainloop in all code
+        self.window.mainloop()
+        
+    def ask_name(self):
+        # show Toplevel
+        self.box = NameInputBox('Input the Name:')
+        
+        # set it modal (to wait for value)
+        self.box.window.focus_set()   # take over input focus,
+        self.box.window.grab_set()    # disable other windows while it is open,
+        self.box.window.wait_window() # and wait here until window destroyed
+        
+        # get value from Toplevel
+        self.label['text'] = self.box.entry_value
+
+if __name__ == '__main__':        
+    MainWindow()