1 files changed, 8 insertions, 1 deletions
diff --git a/toolbar.py b/toolbar.py
index dfb3a82..8490ef5 100644
--- a/toolbar.py
+++ b/toolbar.py
@@ -80,11 +80,18 @@ class PaintToolbar(ToolbarBox):
 
     def set_drawing(self, drawing):
         self._drawing = drawing
+        self._drawing.connect('width-changed', self._width_changed_cb)
         self._update_buttons()
 
+    def _update_width_spin(self, width):
+        self._width_spin.props.value = width
+
     def _update_buttons(self):
         width = self._drawing.get_stroke_width()
-        self._width_spin.props.value = width
+        self._update_width_spin(width)
+
+    def _width_changed_cb(self, widget, width):
+        self._update_width_spin(width)
 
     def _width_spin_cb(self, width_spin):
         width = width_spin.get_value_as_int()