TreeNode: fixed an issue where tree lines are not drawn on node opening frame. (#2920)

imgui_widgets.cpp

@@ -6690,7 +6690,7 @@ bool ImGui::TreeNodeBehavior(ImGuiID id, ImGuiTreeNodeFlags flags, const char* l
     if ((flags & ImGuiTreeNodeFlags_DrawLinesMask_) == 0)
         flags |= g.Style.TreeLinesFlags;
     const bool draw_tree_lines = (flags & (ImGuiTreeNodeFlags_DrawLinesFull | ImGuiTreeNodeFlags_DrawLinesToNodes)) && (frame_bb.Min.y < window->ClipRect.Max.y) && (g.Style.TreeLinesSize > 0.0f);
-    if (is_open && !(flags & ImGuiTreeNodeFlags_NoTreePushOnOpen))
+    if (!(flags & ImGuiTreeNodeFlags_NoTreePushOnOpen))
     {
         if ((flags & ImGuiTreeNodeFlags_NavLeftJumpsToParent) && !g.NavIdIsAlive)
             if (g.NavMoveDir == ImGuiDir_Left && g.NavWindow == window && NavMoveRequestButNoResultYet())
@@ -6889,7 +6889,7 @@ bool ImGui::TreeNodeBehavior(ImGuiID id, ImGuiTreeNodeFlags flags, const char* l
             TablePopBackgroundChannel();
     }
 
-    if (store_tree_node_stack_data && is_open)
+    if (is_open && store_tree_node_stack_data)
         TreeNodeStoreStackData(flags, text_pos.x - text_offset_x); // Call before TreePushOverrideID()
     if (is_open && !(flags & ImGuiTreeNodeFlags_NoTreePushOnOpen))
         TreePushOverrideID(id); // Could use TreePush(label) but this avoid computing twice