Docs: amend docs to explain case of using multiple overlayed ButtonBe…

…havior(). (#8030, #7961, #7669)

docs/CHANGELOG.txt

@@ -101,6 +101,14 @@ Other changes:
 
 Decorated log and release notes: https://github.com/ocornut/imgui/releases/tag/v1.91.2
 
+Breaking changes:
+
+ - Internals: using multiple overlayed ButtonBehavior() with same ID will now have the
+   io.ConfigDebugHighlightIdConflicts=true feature emit a warning. (#8030)
+   It was one of the rare case where using same ID is legal. Workarounds:
+   - use single ButtonBehavior() call with multiple _MouseButton flags
+   - or surround the calls with PushItemFlag(ImGuiItemFlags_AllowDuplicateId, true); ... PopItemFlag()
+
 Other changes:
 
 - Added io.ConfigDebugHighlightIdConflicts debug feature! (#7961, #7669)

imgui.cpp

@@ -433,6 +433,8 @@ CODE
  - 2024/10/03 (1.91.3) - drags: treat v_min==v_max as a valid clamping range when != 0.0f. Zero is a still special value due to legacy reasons, unless using ImGuiSliderFlags_ClampZeroRange. (#7968, #3361, #76)
                        - drags: extended behavior of ImGuiSliderFlags_AlwaysClamp to include _ClampZeroRange. It considers v_min==v_max==0.0f as a valid clamping range (aka edits not allowed).
                          although unlikely, it you wish to only clamp on text input but want v_min==v_max==0.0f to mean unclamped drags, you can use _ClampOnInput instead of _AlwaysClamp. (#7968, #3361, #76)
+ - 2024/09/10 (1.91.2) - internals: using multiple overlayed ButtonBehavior() with same ID will now have io.ConfigDebugHighlightIdConflicts=true feature emit a warning. (#8030)
+                         it was one of the rare case where using same ID is legal. workarounds: (1) use single ButtonBehavior() call with multiple _MouseButton flags, or (2) surround the calls with PushItemFlag(ImGuiItemFlags_AllowDuplicateId, true); ... PopItemFlag()
  - 2024/08/23 (1.91.1) - renamed ImGuiChildFlags_Border to ImGuiChildFlags_Borders for consistency. kept inline redirection flag.
  - 2024/08/22 (1.91.1) - moved some functions from ImGuiIO to ImGuiPlatformIO structure:
                             - io.GetClipboardTextFn         -> platform_io.Platform_GetClipboardTextFn + changed 'void* user_data' to 'ImGuiContext* ctx'. Pull your user data from platform_io.ClipboardUserData.
@@ -10656,9 +10658,10 @@ void ImGui::ErrorCheckEndFrameFinalizeErrorTooltip()
         Text("Programmer error: %d visible items with conflicting ID!", g.DebugDrawIdConflictsCount);
         BulletText("Code should use PushID()/PopID() in loops, or append \"##xx\" to same-label identifiers!");
         BulletText("Empty label e.g. Button(\"\") == same ID as parent widget/node. Use Button(\"##xx\") instead!");
+        //BulletText("Code intending to use duplicate ID may use e.g. PushItemFlag(ImGuiItemFlags_AllowDuplicateId, true); ... PopItemFlag()"); // Not making this too visible for fear of it being abused.
         BulletText("Set io.ConfigDebugDetectIdConflicts=false to disable this warning in non-programmers builds.");
         Separator();
-        Text("(Hold CTRL and: use");
+        Text("(Hold CTRL to: use");
         SameLine();
         if (SmallButton("Item Picker"))
             DebugStartItemPicker();
@@ -10673,7 +10676,7 @@ void ImGui::ErrorCheckEndFrameFinalizeErrorTooltip()
     if (g.ErrorCountCurrentFrame > 0 && BeginErrorTooltip()) // Amend at end of frame
     {
         Separator();
-        Text("(Hold CTRL and:");
+        Text("(Hold CTRL to:");
         SameLine();
         if (SmallButton("Enable Asserts"))
             g.IO.ConfigErrorRecoveryEnableAssert = true;

imgui_widgets.cpp

@@ -482,9 +482,14 @@ void ImGui::BulletTextV(const char* fmt, va_list args)
 //   Frame N + RepeatDelay + RepeatRate*N   true                     true              -                   true
 //-------------------------------------------------------------------------------------------------------------------------------------------------
 
-// FIXME: For refactor we could output flags, incl mouse hovered vs nav keyboard vs nav triggered etc.
-// And better standardize how widgets use 'GetColor32((held && hovered) ? ... : hovered ? ...)' vs 'GetColor32(held ? ... : hovered ? ...);'
-// For mouse feedback we typically prefer the 'held && hovered' test, but for nav feedback not always. Outputting hovered=true on Activation may be misleading.
+// - FIXME: For refactor we could output flags, incl mouse hovered vs nav keyboard vs nav triggered etc.
+//   And better standardize how widgets use 'GetColor32((held && hovered) ? ... : hovered ? ...)' vs 'GetColor32(held ? ... : hovered ? ...);'
+//   For mouse feedback we typically prefer the 'held && hovered' test, but for nav feedback not always. Outputting hovered=true on Activation may be misleading.
+// - Since v1.91.2 (Sept 2024) we included io.ConfigDebugHighlightIdConflicts feature.
+//   One idiom which was previously valid which will now emit a warning is when using multiple overlayed ButtonBehavior()
+//   with same ID and different MouseButton (see #8030). You can fix it by:
+//       (1) switching to use a single ButtonBehavior() with multiple _MouseButton flags.
+//    or (2) surrounding those calls with PushItemFlag(ImGuiItemFlags_AllowDuplicateId, true); ... PopItemFlag()
 bool ImGui::ButtonBehavior(const ImRect& bb, ImGuiID id, bool* out_hovered, bool* out_held, ImGuiButtonFlags flags)
 {
     ImGuiContext& g = *GImGui;