From 6b3ccd3edfcd0ff9fb44060bea092f91b1522795 Mon Sep 17 00:00:00 2001
From: ocornut <omarcornut@gmail.com>
Date: Tue, 26 May 2015 18:02:42 +0100
Subject: [PATCH] WIP Menus: Added support for disabled sub-menu (#126)

---
 imgui.cpp | 16 ++++++++++++----
 imgui.h   |  2 +-
 2 files changed, 13 insertions(+), 5 deletions(-)

diff --git a/imgui.cpp b/imgui.cpp
index 3825607f9..8bd962003 100644
--- a/imgui.cpp
+++ b/imgui.cpp
@@ -7343,6 +7343,8 @@ static bool SelectableEx(const char* label, bool selected, const ImVec2& size_ar
 
     bool hovered, held;
     bool pressed = ButtonBehavior(bb_with_spacing, id, &hovered, &held, true, ((flags & ImGuiSelectableFlags_MenuItem) ? ImGuiButtonFlags_PressedOnClick : 0) | ((flags & ImGuiSelectableFlags_Disabled) ? ImGuiButtonFlags_Disabled : 0));
+    if (flags & ImGuiSelectableFlags_Disabled)
+        selected = false;
 
     // Render
     if (hovered || selected)
@@ -7574,7 +7576,7 @@ void ImGui::EndMenuBar()
     window->DC.MenuBarAppending = false;
 }
 
-bool ImGui::BeginMenu(const char* label)
+bool ImGui::BeginMenu(const char* label, bool enabled)
 {
     ImGuiWindow* window = GetCurrentWindow();
     if (window->SkipItems)
@@ -7600,7 +7602,7 @@ bool ImGui::BeginMenu(const char* label)
         window->DC.CursorPos.x += (float)(int)(style.ItemSpacing.x * 0.5f);
         ImGui::PushStyleVar(ImGuiStyleVar_ItemSpacing, style.ItemSpacing * 2.0f);
         float w = label_size.x;
-        pressed = SelectableEx(label, opened, ImVec2(w, 0.0f), ImVec2(w, 0.0f), ImGuiSelectableFlags_MenuItem | ImGuiSelectableFlags_DontClosePopups);
+        pressed = SelectableEx(label, opened, ImVec2(w, 0.0f), ImVec2(w, 0.0f), ImGuiSelectableFlags_MenuItem | ImGuiSelectableFlags_DontClosePopups | (!enabled ? ImGuiSelectableFlags_Disabled : 0));
         ImGui::PopStyleVar();
         ImGui::SameLine();
         window->DC.CursorPos.x += (float)(int)(style.ItemSpacing.x * 0.5f);
@@ -7610,11 +7612,13 @@ bool ImGui::BeginMenu(const char* label)
         popup_pos = ImVec2(pos.x, pos.y - style.WindowPadding.y);
         float w = window->MenuColumns.DeclColumns(label_size.x, 0.0f, (float)(int)(g.FontSize * 1.20f)); // Feedback to next frame
         float extra_w = ImMax(0.0f, window->Pos.x + ImGui::GetContentRegionMax().x - pos.x - w);
-        pressed = SelectableEx(label, opened, ImVec2(w, 0.0f), ImVec2(0.0f, 0.0f), ImGuiSelectableFlags_MenuItem | ImGuiSelectableFlags_DontClosePopups);
+        pressed = SelectableEx(label, opened, ImVec2(w, 0.0f), ImVec2(0.0f, 0.0f), ImGuiSelectableFlags_MenuItem | ImGuiSelectableFlags_DontClosePopups | (!enabled ? ImGuiSelectableFlags_Disabled : 0));
+        if (!enabled) ImGui::PushStyleColor(ImGuiCol_Text, g.Style.Colors[ImGuiCol_TextDisabled]);
         RenderCollapseTriangle(pos + ImVec2(window->MenuColumns.Pos[2] + extra_w + g.FontSize * 0.20f, 0.0f), false);
+        if (!enabled) ImGui::PopStyleColor();
     }
 
-    bool hovered = IsHovered(window->DC.LastItemRect, id);
+    bool hovered = enabled && IsHovered(window->DC.LastItemRect, id);
     if (menuset_opened)
         g.FocusedWindow = backed_focused_window;
 
@@ -11415,6 +11419,10 @@ static void ShowExampleMenuFile()
             ImGui::MenuItem(ImGui::GetStyleColName((ImGuiCol)i));
         ImGui::EndMenu();
     }
+    if (ImGui::BeginMenu("Disabled", false)) // Disabled
+    {
+        IM_ASSERT(0);
+    }
     if (ImGui::MenuItem("Quit", "Alt+F4")) {}
 }
 
diff --git a/imgui.h b/imgui.h
index b3a5b9d0b..9c828a5c0 100644
--- a/imgui.h
+++ b/imgui.h
@@ -304,7 +304,7 @@ namespace ImGui
     IMGUI_API void          EndMainMenuBar();
     IMGUI_API bool          BeginMenuBar();                                                     // append to menu-bar of current window. only call EndMenuBar() if this returns true!
     IMGUI_API void          EndMenuBar();
-    IMGUI_API bool          BeginMenu(const char* label);                                       // create a sub-menu entry. only call EndMenu() if this returns true!
+    IMGUI_API bool          BeginMenu(const char* label, bool enabled = true);                  // create a sub-menu entry. only call EndMenu() if this returns true!
     IMGUI_API void          EndMenu();
     IMGUI_API bool          MenuItem(const char* label, const char* shortcut = NULL, bool selected = false, bool enabled = true);  // return true when activated. shortcuts are displayed for convenience but not processed by ImGui
     IMGUI_API bool          MenuItem(const char* label, const char* shortcut, bool* p_selected, bool enabled = true);              // return true when activated + toggle (*p_selected) if p_selected != NULL