Added most basic form of Disabled flag to disable interactions (but visuals aren't altered), in imgui_internals.h, undocumented/unsupported (#211, #1012)

imgui.cpp

@@ -2051,6 +2051,8 @@ bool ImGui::IsItemHovered(ImGuiHoveredFlags flags)
             return false;
     if (!IsWindowContentHoverable(window, flags))
         return false;
+    if (window->DC.ItemFlags & ImGuiItemFlags_Disabled)
+        return false;
     return true;
 }
 
@@ -2070,6 +2072,8 @@ bool ImGui::ItemHoverable(const ImRect& bb, ImGuiID id)
         return false;
     if (!IsWindowContentHoverable(window, ImGuiHoveredFlags_Default))
         return false;
+    if (window->DC.ItemFlags & ImGuiItemFlags_Disabled)
+        return false;
 
     SetHoveredID(id);
     return true;
@@ -2090,7 +2094,7 @@ bool ImGui::FocusableItemRegister(ImGuiWindow* window, ImGuiID id, bool tab_stop
 {
     ImGuiContext& g = *GImGui;
 
-    const bool allow_keyboard_focus = (window->DC.ItemFlags & ImGuiItemFlags_AllowKeyboardFocus) != 0;
+    const bool allow_keyboard_focus = (window->DC.ItemFlags & (ImGuiItemFlags_AllowKeyboardFocus | ImGuiItemFlags_Disabled)) == ImGuiItemFlags_AllowKeyboardFocus;
     window->FocusIdxAllCounter++;
     if (allow_keyboard_focus)
         window->FocusIdxTabCounter++;

imgui_internal.h

@@ -582,9 +582,10 @@ enum ImGuiItemFlags_
 {
     ImGuiItemFlags_AllowKeyboardFocus           = 1 << 0,  // true
     ImGuiItemFlags_ButtonRepeat                 = 1 << 1,  // false    // Button() will return true multiple times based on io.KeyRepeatDelay and io.KeyRepeatRate settings.
-    //ImGuiItemFlags_Disabled                   = 1 << 2,  // false    // All widgets appears are disabled
-    //ImGuiItemFlags_AllowNavDefaultFocus       = 1 << 3,  // true
-    ImGuiItemFlags_SelectableDontClosePopup     = 1 << 4,  // false    // MenuItem/Selectable() automatically closes current Popup window
+    ImGuiItemFlags_Disabled                     = 1 << 2,  // false    // FIXME-WIP: Disable interactions but doesn't affect visuals. Should be: grey out and disable interactions with widgets that affect data + view widgets (WIP) 
+    //ImGuiItemFlags_NoNav                      = 1 << 3,  // false
+    //ImGuiItemFlags_NoNavDefaultFocus          = 1 << 4,  // false
+    ImGuiItemFlags_SelectableDontClosePopup     = 1 << 5,  // false    // MenuItem/Selectable() automatically closes current Popup window
     ImGuiItemFlags_Default_                     = ImGuiItemFlags_AllowKeyboardFocus
 };