add class Frame and class Massage, delete funktion go 100%, add resize window

wg_func.py

@@ -3,7 +3,30 @@ import os
 import subprocess
 from tkinter import filedialog
 import tkinter as tk
-from tkinter import messagebox
+
+
+class Message(tk.Tk):
+    def __init__(self, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+
+        self.warning_pic = None
+        self.x_width = 300
+        self.y_height = 120
+        self.monitor_center_x = self.winfo_screenwidth() / 2 - (self.x_width / 2)
+        self.monitor_center_y = self.winfo_screenheight() / 2 - (self.y_height / 2)
+        self.resizable(width=False, height=False)
+        self.title('Import error!')
+        self.configure()
+        self.geometry('%dx%d+%d+%d' % (self.x_width, self.y_height, self.monitor_center_x, self.monitor_center_y))
+        self.columnconfigure(0, weight=1)
+
+        self.label = tk.Label(self, image=self.warning_pic, text='Oh... no valid Wireguard File!\nPlease select a '
+                                                                 'valid Wireguard File')
+        self.label.config(font=("Ubuntu", 11), padx=15, pady=15)
+        self.label.grid(column=0, row=0)
+        self.button = tk.Button(self, text="OK", command=self.destroy)
+        self.button.config(padx=15, pady=5)
+        self.button.grid(column=0, row=1)
 
 
 def active():  # Shows the active tunnel
@@ -21,7 +44,7 @@ a = active()
 
 def tl_list():
     wg_s = os.popen('nmcli con show | grep -iPo "(.*)(wireguard)"').read().split()
-    tl = wg_s[::3]  # tl = Tunnelliste # Hiermit wird jedes 4. Element der Liste gezeigt
+    tl = wg_s[::3]  # tl = Tunnel list # Show of 4.Element in list
     return tl
 
 
@@ -48,20 +71,13 @@ def wg_import_select():
                 os.system('nmcli connection import type wireguard file ' + str(filepath))
                 os.system('nmcli con mod ' + str(pathsplit1[:-5]) + ' connection.autoconnect no')
         if "PrivateKey = " not in read:
-            messagebox.showwarning(title="conf error", message="  Oh... no valid Wireguard File!\nPlease select a "
-                                                               "valid Wireguard File  ")
+            Message()
     except EOFError:
         pass
     except TypeError:
         pass
 
 
-def tl_list():
-    wg_s = os.popen('nmcli con show | grep -iPo "(.*)(wireguard)"').read().split()
-    tl = wg_s[::3]  # tl = Tunnelliste # Hiermit wird jedes 4. Element der Liste gezeigt
-    return tl
-
-
 def wg_export():
     try:
         wg_exp = os.popen('nmcli con show | grep -iPo "(.*)(wireguard)"').read().split()