TreeNode: Internals: facilitate dissociating item ID from storage ID (useful for 1861)

imgui_internal.h

@@ -3461,13 +3461,15 @@ namespace ImGui
     IMGUI_API bool          DragBehavior(ImGuiID id, ImGuiDataType data_type, void* p_v, float v_speed, const void* p_min, const void* p_max, const char* format, ImGuiSliderFlags flags);
     IMGUI_API bool          SliderBehavior(const ImRect& bb, ImGuiID id, ImGuiDataType data_type, void* p_v, const void* p_min, const void* p_max, const char* format, ImGuiSliderFlags flags, ImRect* out_grab_bb);
     IMGUI_API bool          SplitterBehavior(const ImRect& bb, ImGuiID id, ImGuiAxis axis, float* size1, float* size2, float min_size1, float min_size2, float hover_extend = 0.0f, float hover_visibility_delay = 0.0f, ImU32 bg_col = 0);
-    IMGUI_API bool          TreeNodeBehavior(ImGuiID id, ImGuiTreeNodeFlags flags, const char* label, const char* label_end = NULL);
-    IMGUI_API void          TreePushOverrideID(ImGuiID id);
-    IMGUI_API bool          TreeNodeIsOpen(ImGuiID id);
-    IMGUI_API void          TreeNodeSetOpen(ImGuiID id, bool open);
-    IMGUI_API bool          TreeNodeUpdateNextOpen(ImGuiID id, ImGuiTreeNodeFlags flags);   // Return open state. Consume previous SetNextItemOpen() data, if any. May return true when logging.
     IMGUI_API void          SetNextItemSelectionUserData(ImGuiSelectionUserData selection_user_data);
 
+    // Widgets: Tree Nodes
+    IMGUI_API bool          TreeNodeBehavior(ImGuiID id, ImGuiID storage_id, ImGuiTreeNodeFlags flags, const char* label, const char* label_end = NULL);
+    IMGUI_API void          TreePushOverrideID(ImGuiID id);
+    IMGUI_API bool          TreeNodeIsOpen(ImGuiID storage_id);
+    IMGUI_API void          TreeNodeSetOpen(ImGuiID storage_id, bool open);
+    IMGUI_API bool          TreeNodeUpdateNextOpen(ImGuiID storage_id, ImGuiTreeNodeFlags flags);   // Return open state. Consume previous SetNextItemOpen() data, if any. May return true when logging.
+
     // Template functions are instantiated in imgui_widgets.cpp for a finite number of types.
     // To use them externally (for custom widget) you may need an "extern template" statement in your code in order to link to existing instances and silence Clang warnings (see #2036).
     // e.g. " extern template IMGUI_API float RoundScalarWithFormatT<float, float>(const char* format, ImGuiDataType data_type, float v); "

imgui_widgets.cpp

@@ -6195,7 +6195,8 @@ bool ImGui::TreeNode(const char* label)
     ImGuiWindow* window = GetCurrentWindow();
     if (window->SkipItems)
         return false;
-    return TreeNodeBehavior(window->GetID(label), 0, label, NULL);
+    ImGuiID id = window->GetID(label);
+    return TreeNodeBehavior(id, id, ImGuiTreeNodeFlags_None, label, NULL);
 }
 
 bool ImGui::TreeNodeV(const char* str_id, const char* fmt, va_list args)
@@ -6213,8 +6214,8 @@ bool ImGui::TreeNodeEx(const char* label, ImGuiTreeNodeFlags flags)
     ImGuiWindow* window = GetCurrentWindow();
     if (window->SkipItems)
         return false;
-
-    return TreeNodeBehavior(window->GetID(label), flags, label, NULL);
+    ImGuiID id = window->GetID(label);
+    return TreeNodeBehavior(id, id, flags, label, NULL);
 }
 
 bool ImGui::TreeNodeEx(const char* str_id, ImGuiTreeNodeFlags flags, const char* fmt, ...)
@@ -6241,9 +6242,10 @@ bool ImGui::TreeNodeExV(const char* str_id, ImGuiTreeNodeFlags flags, const char
     if (window->SkipItems)
         return false;
 
+    ImGuiID id = window->GetID(str_id);
     const char* label, *label_end;
     ImFormatStringToTempBufferV(&label, &label_end, fmt, args);
-    return TreeNodeBehavior(window->GetID(str_id), flags, label, label_end);
+    return TreeNodeBehavior(id, id, flags, label, label_end);
 }
 
 bool ImGui::TreeNodeExV(const void* ptr_id, ImGuiTreeNodeFlags flags, const char* fmt, va_list args)
@@ -6252,26 +6254,27 @@ bool ImGui::TreeNodeExV(const void* ptr_id, ImGuiTreeNodeFlags flags, const char
     if (window->SkipItems)
         return false;
 
+    ImGuiID id = window->GetID(ptr_id);
     const char* label, *label_end;
     ImFormatStringToTempBufferV(&label, &label_end, fmt, args);
-    return TreeNodeBehavior(window->GetID(ptr_id), flags, label, label_end);
+    return TreeNodeBehavior(id, id, flags, label, label_end);
 }
 
-bool ImGui::TreeNodeIsOpen(ImGuiID id)
+bool ImGui::TreeNodeIsOpen(ImGuiID storage_id)
 {
     ImGuiContext& g = *GImGui;
     ImGuiStorage* storage = g.CurrentWindow->DC.StateStorage;
-    return storage->GetInt(id, 0) != 0;
+    return storage->GetInt(storage_id, 0) != 0;
 }
 
-void ImGui::TreeNodeSetOpen(ImGuiID id, bool open)
+void ImGui::TreeNodeSetOpen(ImGuiID storage_id, bool open)
 {
     ImGuiContext& g = *GImGui;
     ImGuiStorage* storage = g.CurrentWindow->DC.StateStorage;
-    storage->SetInt(id, open ? 1 : 0);
+    storage->SetInt(storage_id, open ? 1 : 0);
 }
 
-bool ImGui::TreeNodeUpdateNextOpen(ImGuiID id, ImGuiTreeNodeFlags flags)
+bool ImGui::TreeNodeUpdateNextOpen(ImGuiID storage_id, ImGuiTreeNodeFlags flags)
 {
     if (flags & ImGuiTreeNodeFlags_Leaf)
         return true;
@@ -6287,16 +6290,16 @@ bool ImGui::TreeNodeUpdateNextOpen(ImGuiID id, ImGuiTreeNodeFlags flags)
         if (g.NextItemData.OpenCond & ImGuiCond_Always)
         {
             is_open = g.NextItemData.OpenVal;
-            TreeNodeSetOpen(id, is_open);
+            TreeNodeSetOpen(storage_id, is_open);
         }
         else
         {
             // We treat ImGuiCond_Once and ImGuiCond_FirstUseEver the same because tree node state are not saved persistently.
-            const int stored_value = storage->GetInt(id, -1);
+            const int stored_value = storage->GetInt(storage_id, -1);
             if (stored_value == -1)
             {
                 is_open = g.NextItemData.OpenVal;
-                TreeNodeSetOpen(id, is_open);
+                TreeNodeSetOpen(storage_id, is_open);
             }
             else
             {
@@ -6306,7 +6309,7 @@ bool ImGui::TreeNodeUpdateNextOpen(ImGuiID id, ImGuiTreeNodeFlags flags)
     }
     else
     {
-        is_open = storage->GetInt(id, (flags & ImGuiTreeNodeFlags_DefaultOpen) ? 1 : 0) != 0;
+        is_open = storage->GetInt(storage_id, (flags & ImGuiTreeNodeFlags_DefaultOpen) ? 1 : 0) != 0;
     }
 
     // When logging is enabled, we automatically expand tree nodes (but *NOT* collapsing headers.. seems like sensible behavior).
@@ -6333,7 +6336,8 @@ static void TreeNodeStoreStackData(ImGuiTreeNodeFlags flags)
     window->DC.TreeHasStackDataDepthMask |= (1 << window->DC.TreeDepth);
 }
 
-bool ImGui::TreeNodeBehavior(ImGuiID id, ImGuiTreeNodeFlags flags, const char* label, const char* label_end)
+// When using public API, currently 'id == storage_id' is always true, but we separate the values to facilitate advanced user code doing storage queries outside of UI loop.
+bool ImGui::TreeNodeBehavior(ImGuiID id, ImGuiID storage_id, ImGuiTreeNodeFlags flags, const char* label, const char* label_end)
 {
     ImGuiWindow* window = GetCurrentWindow();
     if (window->SkipItems)
@@ -6386,7 +6390,7 @@ bool ImGui::TreeNodeBehavior(ImGuiID id, ImGuiTreeNodeFlags flags, const char* l
     }
 
     // Compute open and multi-select states before ItemAdd() as it clear NextItem data.
-    bool is_open = TreeNodeUpdateNextOpen(id, flags);
+    bool is_open = TreeNodeUpdateNextOpen(storage_id, flags);
     bool item_add = ItemAdd(interact_bb, id);
     g.LastItemData.StatusFlags |= ImGuiItemStatusFlags_HasDisplayRect;
     g.LastItemData.DisplayRect = frame_bb;
@@ -6498,7 +6502,7 @@ bool ImGui::TreeNodeBehavior(ImGuiID id, ImGuiTreeNodeFlags flags, const char* l
         if (toggled)
         {
             is_open = !is_open;
-            window->DC.StateStorage->SetInt(id, is_open);
+            window->DC.StateStorage->SetInt(storage_id, is_open);
             g.LastItemData.StatusFlags |= ImGuiItemStatusFlags_ToggledOpen;
         }
     }
@@ -6639,8 +6643,8 @@ bool ImGui::CollapsingHeader(const char* label, ImGuiTreeNodeFlags flags)
     ImGuiWindow* window = GetCurrentWindow();
     if (window->SkipItems)
         return false;
-
-    return TreeNodeBehavior(window->GetID(label), flags | ImGuiTreeNodeFlags_CollapsingHeader, label);
+    ImGuiID id = window->GetID(label);
+    return TreeNodeBehavior(id, id, flags | ImGuiTreeNodeFlags_CollapsingHeader, label);
 }
 
 // p_visible == NULL                        : regular collapsing header
@@ -6660,7 +6664,7 @@ bool ImGui::CollapsingHeader(const char* label, bool* p_visible, ImGuiTreeNodeFl
     flags |= ImGuiTreeNodeFlags_CollapsingHeader;
     if (p_visible)
         flags |= ImGuiTreeNodeFlags_AllowOverlap | (ImGuiTreeNodeFlags)ImGuiTreeNodeFlags_ClipLabelForTrailingButton;
-    bool is_open = TreeNodeBehavior(id, flags, label);
+    bool is_open = TreeNodeBehavior(id, id, flags, label);
     if (p_visible != NULL)
     {
         // Create a small overlapping close button