Internals: Added SetLastItemData, rename ImGuiItemHoveredDataBackup to ImGuiLastItemDataBackup.

imgui.cpp

@@ -3100,6 +3100,15 @@ bool ImGui::IsClippedEx(const ImRect& bb, ImGuiID id, bool clip_even_when_logged
     return false;
 }
 
+// This is also inlined in ItemAdd()
+// Note: if ImGuiItemStatusFlags_HasDisplayRect is set, user needs to set window->DC.LastItemDisplayRect!
+void ImGui::SetLastItemData(ImGuiWindow* window, ImGuiID item_id, ImGuiItemStatusFlags item_flags, const ImRect& item_rect)
+{
+    window->DC.LastItemId = item_id;
+    window->DC.LastItemStatusFlags = item_flags;
+    window->DC.LastItemRect = item_rect;
+}
+
 // Process TAB/Shift+TAB. Be mindful that this function may _clear_ the ActiveID when tabbing out.
 bool ImGui::FocusableItemRegister(ImGuiWindow* window, ImGuiID id)
 {
@@ -5980,9 +5989,8 @@ bool ImGui::Begin(const char* name, bool* p_open, ImGuiWindowFlags flags)
 
         // We fill last item data based on Title Bar/Tab, in order for IsItemHovered() and IsItemActive() to be usable after Begin().
         // This is useful to allow creating context menus on title bar only, etc.
-        window->DC.LastItemId = window->MoveId;
-        window->DC.LastItemStatusFlags = IsMouseHoveringRect(title_bar_rect.Min, title_bar_rect.Max, false) ? ImGuiItemStatusFlags_HoveredRect : 0;
-        window->DC.LastItemRect = title_bar_rect;
+        SetLastItemData(window, window->MoveId, IsMouseHoveringRect(title_bar_rect.Min, title_bar_rect.Max, false) ? ImGuiItemStatusFlags_HoveredRect : 0, title_bar_rect);
+
 #ifdef IMGUI_ENABLE_TEST_ENGINE
         if (!(window->Flags & ImGuiWindowFlags_NoTitleBar))
             IMGUI_TEST_ENGINE_ITEM_ADD(window->DC.LastItemRect, window->DC.LastItemId);
@@ -6959,6 +6967,7 @@ bool ImGui::ItemAdd(const ImRect& bb, ImGuiID id, const ImRect* nav_bb_arg)
 #endif
     }
 
+    // Equivalent to calling SetLastItemData()
     window->DC.LastItemId = id;
     window->DC.LastItemRect = bb;
     window->DC.LastItemStatusFlags = ImGuiItemStatusFlags_None;

imgui_internal.h

@@ -96,7 +96,7 @@ struct ImGuiContext;                // Main Dear ImGui context
 struct ImGuiDataTypeInfo;           // Type information associated to a ImGuiDataType enum
 struct ImGuiGroupData;              // Stacked storage data for BeginGroup()/EndGroup()
 struct ImGuiInputTextState;         // Internal state of the currently focused/edited text input box
-struct ImGuiItemHoveredDataBackup;  // Backup and restore IsItemHovered() internal data
+struct ImGuiLastItemDataBackup;     // Backup and restore IsItemHovered() internal data
 struct ImGuiMenuColumns;            // Simple column measurement, currently used for MenuItem() only
 struct ImGuiNavMoveResult;          // Result of a gamepad/keyboard directional navigation move query result
 struct ImGuiNextWindowData;         // Storage for SetNextWindow** functions
@@ -1664,14 +1664,14 @@ public:
 };
 
 // Backup and restore just enough data to be able to use IsItemHovered() on item A after another B in the same window has overwritten the data.
-struct ImGuiItemHoveredDataBackup
+struct ImGuiLastItemDataBackup
 {
     ImGuiID                 LastItemId;
     ImGuiItemStatusFlags    LastItemStatusFlags;
     ImRect                  LastItemRect;
     ImRect                  LastItemDisplayRect;
 
-    ImGuiItemHoveredDataBackup() { Backup(); }
+    ImGuiLastItemDataBackup() { Backup(); }
     void Backup()           { ImGuiWindow* window = GImGui->CurrentWindow; LastItemId = window->DC.LastItemId; LastItemStatusFlags = window->DC.LastItemStatusFlags; LastItemRect = window->DC.LastItemRect; LastItemDisplayRect = window->DC.LastItemDisplayRect; }
     void Restore() const    { ImGuiWindow* window = GImGui->CurrentWindow; window->DC.LastItemId = LastItemId; window->DC.LastItemStatusFlags = LastItemStatusFlags; window->DC.LastItemRect = LastItemRect; window->DC.LastItemDisplayRect = LastItemDisplayRect; }
 };
@@ -1839,6 +1839,7 @@ namespace ImGui
     IMGUI_API bool          ItemAdd(const ImRect& bb, ImGuiID id, const ImRect* nav_bb = NULL);
     IMGUI_API bool          ItemHoverable(const ImRect& bb, ImGuiID id);
     IMGUI_API bool          IsClippedEx(const ImRect& bb, ImGuiID id, bool clip_even_when_logged);
+    IMGUI_API void          SetLastItemData(ImGuiWindow* window, ImGuiID item_id, ImGuiItemStatusFlags status_flags, const ImRect& item_rect);
     IMGUI_API bool          FocusableItemRegister(ImGuiWindow* window, ImGuiID id);   // Return true if focus is requested
     IMGUI_API void          FocusableItemUnregister(ImGuiWindow* window);
     IMGUI_API ImVec2        CalcItemSize(ImVec2 size, float default_w, float default_h);

imgui_widgets.cpp

@@ -5661,7 +5661,7 @@ bool ImGui::CollapsingHeader(const char* label, bool* p_open, ImGuiTreeNodeFlags
         // FIXME: We can evolve this into user accessible helpers to add extra buttons on title bars, headers, etc.
         // FIXME: CloseButton can overlap into text, need find a way to clip the text somehow.
         ImGuiContext& g = *GImGui;
-        ImGuiItemHoveredDataBackup last_item_backup;
+        ImGuiLastItemDataBackup last_item_backup;
         float button_size = g.FontSize;
         float button_x = ImMax(window->DC.LastItemRect.Min.x, window->DC.LastItemRect.Max.x - g.Style.FramePadding.x * 2.0f - button_size);
         float button_y = window->DC.LastItemRect.Min.y;
@@ -7410,7 +7410,7 @@ bool ImGui::TabItemLabelAndCloseButton(ImDrawList* draw_list, const ImRect& bb,
                 close_button_visible = true;
     if (close_button_visible)
     {
-        ImGuiItemHoveredDataBackup last_item_backup;
+        ImGuiLastItemDataBackup last_item_backup;
         const float close_button_sz = g.FontSize;
         PushStyleVar(ImGuiStyleVar_FramePadding, frame_padding);
         if (CloseButton(close_button_id, ImVec2(bb.Max.x - frame_padding.x * 2.0f - close_button_sz, bb.Min.y)))