Menus, Nav: Fixed using left/right navigation when appending to an existing menu (multiple BeginMenu() call with same names). (#1207)

docs/CHANGELOG.txt

@@ -137,6 +137,8 @@ Other Changes:
   the gap between a menu item inside a window and a child-menu in a secondary viewport. (#5614)
 - Menus, Nav: Fixed keyboard/gamepad navigation occasionally erroneously landing on menu-item in
   parent when the parent is not a popup. (#5730)
+- Menus, Nav: Fixed using left/right navigation when appending to an existing menu (multiple
+  BeginMenu() call with same names). (#1207)
 - Nav: Fixed moving/resizing window with gamepad or keyboard when running at very high framerate.
 - Nav: Pressing Space/GamepadFaceDown on a repeating button uses the same repeating rate as a mouse hold.
 - Nav: Fixed an issue opening a menu with Right key from a non-menu window.

imgui.cpp

@@ -4608,9 +4608,10 @@ void ImGui::NewFrame()
     {
         ImGuiWindow* window = g.Windows[i];
         window->WasActive = window->Active;
-        window->BeginCount = 0;
         window->Active = false;
         window->WriteAccessed = false;
+        window->BeginCountPreviousFrame = window->BeginCount;
+        window->BeginCount = 0;
 
         // Garbage collect transient buffers of recently unused windows
         if (!window->WasActive && !window->MemoryCompacted && window->LastTimeActive < memory_compact_start_time)

imgui.h

@@ -23,7 +23,7 @@
 // Library Version
 // (Integer encoded as XYYZZ for use in #if preprocessor conditionals, e.g. '#if IMGUI_VERSION_NUM > 12345')
 #define IMGUI_VERSION               "1.89 WIP"
-#define IMGUI_VERSION_NUM           18826
+#define IMGUI_VERSION_NUM           18827
 #define IMGUI_HAS_TABLE
 
 /*

imgui_internal.h

@@ -2112,6 +2112,7 @@ struct IMGUI_API ImGuiWindow
     bool                    HasCloseButton;                     // Set when the window has a close button (p_open != NULL)
     signed char             ResizeBorderHeld;                   // Current border being held for resize (-1: none, otherwise 0-3)
     short                   BeginCount;                         // Number of Begin() during the current frame (generally 0 or 1, 1+ if appending via multiple Begin/End pairs)
+    short                   BeginCountPreviousFrame;            // Number of Begin() during the previous frame
     short                   BeginOrderWithinParent;             // Begin() order within immediate parent window, if we are a child window. Otherwise 0.
     short                   BeginOrderWithinContext;            // Begin() order within entire imgui context. This is mostly used for debugging submission order related issues.
     short                   FocusOrder;                         // Order within WindowsFocusOrder[], altered when windows are focused.

imgui_widgets.cpp

@@ -7183,13 +7183,15 @@ void ImGui::EndMenu()
     // FIXME: This doesn't work if the parent BeginMenu() is not on a menu.
     ImGuiContext& g = *GImGui;
     ImGuiWindow* window = g.CurrentWindow;
+    IM_ASSERT(window->Flags & ImGuiWindowFlags_Popup);  // Mismatched BeginMenu()/EndMenu() calls
+
+    if (window->BeginCount == window->BeginCountPreviousFrame)
         if (g.NavMoveDir == ImGuiDir_Left && NavMoveRequestButNoResultYet() && window->DC.LayoutType == ImGuiLayoutType_Vertical)
             if (g.NavWindow && (g.NavWindow->RootWindowForNav->Flags & ImGuiWindowFlags_Popup) && g.NavWindow->RootWindowForNav->ParentWindow == window)
             {
                 ClosePopupToLevel(g.BeginPopupStack.Size, true);
                 NavMoveRequestCancel();
             }
-
     EndPopup();
 }