[STUDIO] Add tab reordering and better auto-selection mechanics to ta…

…b layout (#51)

studio/feature/design.py

@@ -955,7 +955,8 @@ def _update_stacking(self, indices, silently=False):
         if not indices:
             return
 
-        child_list = next(iter(indices)).layout._children
+        layout = next(iter(indices)).layout
+        child_list = layout._children
         # reorder child list based on indices
 
         indices = sorted(
@@ -981,6 +982,7 @@ def _update_stacking(self, indices, silently=False):
                 widget.lift(widget.layout.body)
 
         prev_data = dict(sorted(prev_data.items(), key=lambda x: x[1]))
+        layout.layout_strategy.widgets_reordered()
 
         if not silently and prev_data != data:
             self.studio.new_action(Action(

studio/lib/layouts.py

@@ -99,6 +99,9 @@ def _update_stacking(self):
             else:
                 widget.lift(self.container.body)
 
+    def widgets_reordered(self):
+        pass
+
     def widget_released(self, widget):
         pass
 
@@ -980,7 +983,7 @@ class TabLayoutStrategy(BaseLayoutStrategy):
     name = "TabLayout"
     icon = "notebook"
     manager = "tab"
-    stacking_support = False
+    stacking_support = True
 
     def __init__(self, master):
         super().__init__(master)
@@ -1014,12 +1017,15 @@ def get_restore(self, widget):
     def _redraw(self, start_index=0):
         affected = self.children[start_index:]
         cache = {}
+        selected = self.container.select()
         for child in affected:
             cache[child] = self.info(child)
             self.container.body.forget(child)
-        for child in affected:
+        for i, child in enumerate(affected):
             self.container.body.add(child)
             self.container.body.tab(child, **cache.get(child, {}))
+            if str(child) == selected:
+                self.container.select(i)
 
     def resize_widget(self, widget, direction, delta):
         pass
@@ -1030,6 +1036,9 @@ def add_widget(self, widget, bounds=None, **kwargs):
         self.container.body.add(widget, text=widget.id)
         self.container.body.tab(widget, **kwargs)
         self._insert(widget)
+        length = len(self.container.tabs())
+        if length > 1:
+            self.container.select(length - 1)
 
     def remove_widget(self, widget):
         super().remove_widget(widget)
@@ -1057,6 +1066,9 @@ def _tab_switched(self, *_):
         # Take its level one place above other tabs
         self._current_tab.level = self.level + 2
 
+    def widgets_reordered(self):
+        self._redraw(0)
+
     def copy_layout(self, widget, from_):
         info = from_.layout.body.tab(from_)
         self.add_widget(widget, (0, 0, 0, 0), **info)