MenuItem(): Tweaks to mimic exact spacing of BeginMenu() when inside a menu bar, which is a little misleading imho but may be useful. (#1387)

imgui.cpp

@@ -9077,24 +9077,38 @@ bool ImGui::MenuItem(const char* label, const char* shortcut, bool selected, boo
         return false;
 
     ImGuiContext& g = *GImGui;
+    ImGuiStyle& style = g.Style;
     ImVec2 pos = window->DC.CursorPos;
     ImVec2 label_size = CalcTextSize(label, NULL, true);
+
+    ImGuiSelectableFlags flags = ImGuiSelectableFlags_MenuItem | (enabled ? 0 : ImGuiSelectableFlags_Disabled);
+    bool pressed;
+    if (window->DC.LayoutType == ImGuiLayoutType_Horizontal)
+    {
+        // Mimic the exact layout spacing of BeginMenu() to allow MenuItem() inside a menu bar, which is a little misleading but may be useful
+        // Note that in this situation we render neither the shortcut neither the selected tick mark
+        float w = label_size.x;
+        window->DC.CursorPos.x += (float)(int)(style.ItemSpacing.x * 0.5f);
+        PushStyleVar(ImGuiStyleVar_ItemSpacing, style.ItemSpacing * 2.0f);
+        pressed = Selectable(label, false, flags, ImVec2(w, 0.0f));
+        PopStyleVar();
+        window->DC.CursorPos.x += (float)(int)(style.ItemSpacing.x * (-1.0f + 0.5f)); // -1 spacing to compensate the spacing added when Selectable() did a SameLine(). It would also work to call SameLine() ourselves after the PopStyleVar().
+    }
+    else
+    {
         ImVec2 shortcut_size = shortcut ? CalcTextSize(shortcut, NULL) : ImVec2(0.0f, 0.0f);
         float w = window->MenuColumns.DeclColumns(label_size.x, shortcut_size.x, (float)(int)(g.FontSize * 1.20f)); // Feedback for next frame
         float extra_w = ImMax(0.0f, GetContentRegionAvail().x - w);
-
-    ImGuiSelectableFlags flags = ImGuiSelectableFlags_MenuItem | (enabled ? 0 : ImGuiSelectableFlags_Disabled) | (window->DC.LayoutType == ImGuiLayoutType_Vertical ? ImGuiSelectableFlags_DrawFillAvailWidth : 0);
-    bool pressed = Selectable(label, false, flags, ImVec2(w, 0.0f));
+        pressed = Selectable(label, false, flags | ImGuiSelectableFlags_DrawFillAvailWidth, ImVec2(w, 0.0f));
         if (shortcut_size.x > 0.0f)
         {
             PushStyleColor(ImGuiCol_Text, g.Style.Colors[ImGuiCol_TextDisabled]);
             RenderText(pos + ImVec2(window->MenuColumns.Pos[1] + extra_w, 0.0f), shortcut, NULL, false);
             PopStyleColor();
         }
-
         if (selected)
             RenderCheckMark(pos + ImVec2(window->MenuColumns.Pos[2] + extra_w + g.FontSize * (0.20f+0.200f), g.FontSize * 0.134f * 0.5f), GetColorU32(enabled ? ImGuiCol_Text : ImGuiCol_TextDisabled), g.FontSize  * 0.866f);
-
+    }
     return pressed;
 }