added automatic minsize of UI to prevent hidden Elements at startup

src/gui.py

@@ -55,7 +55,6 @@ class DHCPApp(tk.Frame):
     def __init__(self, master: tk.Tk) -> None:
         super().__init__(master)
         master.title("Simple DHCP Server (Lab)")
-        master.minsize(700, 500)
         self.pack(fill="both", expand=True, padx=12, pady=12)
 
         # Single server instance
@@ -104,20 +103,20 @@ class DHCPApp(tk.Frame):
         self.btn_rescan.pack(side="left", padx=(8, 0))
 
         # --- Clients & Logs Paned Layout ---
-        paned = ttk.Panedwindow(self, orient="horizontal")
-        paned.pack(fill="both", expand=True)
+        self.paned = ttk.Panedwindow(self, orient="horizontal")
+        self.paned.pack(fill="both", expand=True)
 
         # Clients list
-        left = ttk.Labelframe(paned, text="Aktive Clients / Leases")
+        left = ttk.Labelframe(self.paned, text="Aktive Clients / Leases")
         self.clients = tk.Listbox(left, height=12)
         self.clients.pack(fill="both", expand=True, padx=6, pady=6)
-        paned.add(left, weight=1)
+        self.paned.add(left, weight=1)
 
         # Logs
-        right = ttk.Labelframe(paned, text="Log")
+        right = ttk.Labelframe(self.paned, text="Log")
         self.log = tk.Text(right, height=12, state="disabled")
         self.log.pack(fill="both", expand=True, padx=6, pady=6)
-        paned.add(right, weight=2)
+        self.paned.add(right, weight=2)
 
         # --- Status bar ---
         self.status_var = tk.StringVar(value="Bereit.")
@@ -125,6 +124,9 @@ class DHCPApp(tk.Frame):
         status.pack(fill="x", side="bottom")
 
         self._refresh_interface_list(initial=True)
+        self._apply_min_sizes()
+        self.paned.bind("<Configure>", lambda _e: self._enforce_pane_sizes())
+        self.after_idle(self._enforce_pane_sizes)
 
         # periodic refresh
         self.after(400, self._refresh)
@@ -192,6 +194,30 @@ class DHCPApp(tk.Frame):
             if not initial:
                 self.status_var.set("Keine Netzwerk-Interfaces gefunden.")
 
+    def _apply_min_sizes(self) -> None:
+        # Ensure window cannot shrink below a comfortable layout
+        self.update_idletasks()
+        min_w = max(self.winfo_reqwidth() + 16, 720)
+        min_h = max(self.winfo_reqheight() + 16, 540)
+        self.master.minsize(min_w, min_h)
+
+    def _enforce_pane_sizes(self) -> None:
+        # prevent panes from collapsing too far
+        try:
+            if not self.paned or not self.paned.panes():
+                return
+            total = self.paned.winfo_width()
+            left_min, right_min = 240, 360
+            if total <= left_min + right_min:
+                return
+            pos = self.paned.sashpos(0)
+            if pos < left_min:
+                self.paned.sashpos(0, left_min)
+            elif pos > total - right_min:
+                self.paned.sashpos(0, total - right_min)
+        except Exception:
+            pass
+
     def rescan_interfaces(self) -> None:
         if self.server and self.server.is_running():
             messagebox.showinfo("Server läuft", "Stoppe den Server, bevor du Interfaces neu scannst.")