diff --git a/ttkDesigner/app/designer.py b/ttkDesigner/app/designer.py
index 1863762b..30d7e1cc 100644
--- a/ttkDesigner/app/designer.py
+++ b/ttkDesigner/app/designer.py
@@ -76,7 +76,7 @@ import pickle
 #      └─────────────────────╨───────────────────────────────╨───────────────────┘
 #
 
-class TTkDesigner(TTkGridLayout):
+class TTkDesigner(TTkAppTemplate):
     __slots__ = ('_main', '_toolBar', '_fileNameLabel', '_modified',
                  '_sigslotEditor', '_treeInspector', '_windowEditor', '_notepad',
                  '_fileName', '_currentPath',
@@ -96,7 +96,7 @@ class TTkDesigner(TTkGridLayout):
 
         super().__init__(*args, **kwargs)
 
-        self.addWidget(appTemplate := TTkAppTemplate())
+        appTemplate = self
 
         self._notepad = NotePad()
         self._main = TTkVBoxLayout()
diff --git a/ttkDesigner/app/main.py b/ttkDesigner/app/main.py
index 09c5fbe6..a41c9b08 100644
--- a/ttkDesigner/app/main.py
+++ b/ttkDesigner/app/main.py
@@ -23,7 +23,7 @@
 import argparse
 
 from TermTk import TTk, TTkTheme, TTkTerm
-from TermTk import TTkVBoxLayout, TTkKeyPressView
+from TermTk import TTkGridLayout, TTkKeyPressView
 
 from .designer import TTkDesigner
 
@@ -38,17 +38,17 @@ def main():
     root = TTk(
             title="TTk Designer",
             mouseTrack=True,
+            layout=TTkGridLayout(),
             sigmask=(
                 TTkTerm.Sigmask.CTRL_C |
                 TTkTerm.Sigmask.CTRL_Q |
                 TTkTerm.Sigmask.CTRL_S |
                 TTkTerm.Sigmask.CTRL_Z ))
 
+    root.layout().addWidget(_d:=TTkDesigner(fileName=args.filename))
+
     if args.showkeys:
-        root.setLayout(_l:=TTkVBoxLayout())
-        _l.addItem(TTkDesigner(fileName=args.filename))
-        _l.addWidget(TTkKeyPressView(maxHeight=3))
-    else:
-        root.setLayout(TTkDesigner(fileName=args.filename))
+        _d.setWidget(widget=TTkKeyPressView(maxHeight=3), position=_d.FOOTER, size=3)
+        _d.setFixed(fixed=True, position=_d.FOOTER)
 
     root.mainloop()