diff --git a/src/view/ASubWindow.py b/src/view/ASubWindow.py
index 3764193e2ffc9e4d76741a5866abc768b29dbab4..45ec51753455db5a931eeb82cf627605122ba7d2 100644
--- a/src/view/ASubWindow.py
+++ b/src/view/ASubWindow.py
@@ -25,6 +25,12 @@ class ASubWindow(QDialog):
         self.name = name
         self.parent = parent
         self.parent.sub_win_add(name, self)
+        self.fixed_size()
+
+    def fixed_size(self):
+        width = self.frameGeometry().width()
+        height = self.frameGeometry().height()
+        self.setFixedSize(width, height)
 
     def closeEvent(self, event):
         if not self.parent is None: