TabBar: Internals: added TabItemSpacing(). (#8349, #3291)

imgui_internal.h

@@ -2612,6 +2612,8 @@ enum ImGuiTabItemFlagsPrivate_
     ImGuiTabItemFlags_SectionMask_              = ImGuiTabItemFlags_Leading | ImGuiTabItemFlags_Trailing,
     ImGuiTabItemFlags_NoCloseButton             = 1 << 20,  // Track whether p_open was set or not (we'll need this info on the next frame to recompute ContentWidth during layout)
     ImGuiTabItemFlags_Button                    = 1 << 21,  // Used by TabItemButton, change the tab item behavior to mimic a button
+    ImGuiTabItemFlags_Invisible                 = 1 << 22,  // To reserve space e.g. with ImGuiTabItemFlags_Leading
+    //ImGuiTabItemFlags_Unsorted                = 1 << 23,  // [Docking] Trailing tabs with the _Unsorted flag will be sorted based on the DockOrder of their Window.
 };
 
 // Storage for one active tab item (sizeof() 40 bytes)
@@ -3378,6 +3380,7 @@ namespace ImGui
     IMGUI_API void          TabBarQueueReorderFromMousePos(ImGuiTabBar* tab_bar, ImGuiTabItem* tab, ImVec2 mouse_pos);
     IMGUI_API bool          TabBarProcessReorder(ImGuiTabBar* tab_bar);
     IMGUI_API bool          TabItemEx(ImGuiTabBar* tab_bar, const char* label, bool* p_open, ImGuiTabItemFlags flags, ImGuiWindow* docked_window);
+    IMGUI_API void          TabItemSpacing(const char* str_id, ImGuiTabItemFlags flags, float width);
     IMGUI_API ImVec2        TabItemCalcSize(const char* label, bool has_close_button_or_unsaved_marker);
     IMGUI_API ImVec2        TabItemCalcSize(ImGuiWindow* window);
     IMGUI_API void          TabItemBackground(ImDrawList* draw_list, const ImRect& bb, ImGuiTabItemFlags flags, ImU32 col);

imgui_widgets.cpp

@@ -9925,7 +9925,7 @@ bool    ImGui::BeginTabItem(const char* label, bool* p_open, ImGuiTabItemFlags f
         IM_ASSERT_USER_ERROR(tab_bar, "Needs to be called between BeginTabBar() and EndTabBar()!");
         return false;
     }
-    IM_ASSERT(!(flags & ImGuiTabItemFlags_Button)); // BeginTabItem() Can't be used with button flags, use TabItemButton() instead!
+    IM_ASSERT((flags & ImGuiTabItemFlags_Button) == 0); // BeginTabItem() Can't be used with button flags, use TabItemButton() instead!
 
     bool ret = TabItemEx(tab_bar, label, p_open, flags, NULL);
     if (ret && !(flags & ImGuiTabItemFlags_NoPushId))
@@ -9971,6 +9971,23 @@ bool    ImGui::TabItemButton(const char* label, ImGuiTabItemFlags flags)
     return TabItemEx(tab_bar, label, NULL, flags | ImGuiTabItemFlags_Button | ImGuiTabItemFlags_NoReorder, NULL);
 }
 
+void    ImGui::TabItemSpacing(const char* str_id, ImGuiTabItemFlags flags, float width)
+{
+    ImGuiContext& g = *GImGui;
+    ImGuiWindow* window = g.CurrentWindow;
+    if (window->SkipItems)
+        return;
+
+    ImGuiTabBar* tab_bar = g.CurrentTabBar;
+    if (tab_bar == NULL)
+    {
+        IM_ASSERT_USER_ERROR(tab_bar != NULL, "Needs to be called between BeginTabBar() and EndTabBar()!");
+        return;
+    }
+    SetNextItemWidth(width);
+    TabItemEx(tab_bar, str_id, NULL, flags | ImGuiTabItemFlags_Button | ImGuiTabItemFlags_NoReorder | ImGuiTabItemFlags_Invisible, NULL);
+}
+
 bool    ImGui::TabItemEx(ImGuiTabBar* tab_bar, const char* label, bool* p_open, ImGuiTabItemFlags flags, ImGuiWindow* docked_window)
 {
     // Layout whole tab bar if not already done
@@ -10116,8 +10133,11 @@ bool    ImGui::TabItemEx(ImGuiTabBar* tab_bar, const char* label, bool* p_open,
     ImGuiButtonFlags button_flags = ((is_tab_button ? ImGuiButtonFlags_PressedOnClickRelease : ImGuiButtonFlags_PressedOnClick) | ImGuiButtonFlags_AllowOverlap);
     if (g.DragDropActive)
         button_flags |= ImGuiButtonFlags_PressedOnDragDropHold;
-    bool hovered, held;
-    bool pressed = ButtonBehavior(bb, id, &hovered, &held, button_flags);
+    bool hovered, held, pressed;
+    if (flags & ImGuiTabItemFlags_Invisible)
+        hovered = held = pressed = false;
+    else
+        pressed = ButtonBehavior(bb, id, &hovered, &held, button_flags);
     if (pressed && !is_tab_button)
         TabBarQueueFocus(tab_bar, tab);
 
@@ -10149,46 +10169,59 @@ bool    ImGui::TabItemEx(ImGuiTabBar* tab_bar, const char* label, bool* p_open,
 #endif
 
     // Render tab shape
-    ImDrawList* display_draw_list = window->DrawList;
-    const ImU32 tab_col = GetColorU32((held || hovered) ? ImGuiCol_TabHovered : tab_contents_visible ? (tab_bar_focused ? ImGuiCol_TabSelected : ImGuiCol_TabDimmedSelected) : (tab_bar_focused ? ImGuiCol_Tab : ImGuiCol_TabDimmed));
-    TabItemBackground(display_draw_list, bb, flags, tab_col);
-    if (tab_contents_visible && (tab_bar->Flags & ImGuiTabBarFlags_DrawSelectedOverline) && style.TabBarOverlineSize > 0.0f)
-    {
-        // Might be moved to TabItemBackground() ?
-        ImVec2 tl = bb.GetTL() + ImVec2(0, 1.0f * g.CurrentDpiScale);
-        ImVec2 tr = bb.GetTR() + ImVec2(0, 1.0f * g.CurrentDpiScale);
-        ImU32 overline_col = GetColorU32(tab_bar_focused ? ImGuiCol_TabSelectedOverline : ImGuiCol_TabDimmedSelectedOverline);
-        if (style.TabRounding > 0.0f)
-        {
-            float rounding = style.TabRounding;
-            display_draw_list->PathArcToFast(tl + ImVec2(+rounding, +rounding), rounding, 7, 9);
-            display_draw_list->PathArcToFast(tr + ImVec2(-rounding, +rounding), rounding, 9, 11);
-            display_draw_list->PathStroke(overline_col, 0, style.TabBarOverlineSize);
-        }
-        else
+    const bool is_visible = (g.LastItemData.StatusFlags & ImGuiItemStatusFlags_Visible) && !(flags & ImGuiTabItemFlags_Invisible);
+    if (is_visible)
+    {
+        ImDrawList* display_draw_list = window->DrawList;
+        const ImU32 tab_col = GetColorU32((held || hovered) ? ImGuiCol_TabHovered : tab_contents_visible ? (tab_bar_focused ? ImGuiCol_TabSelected : ImGuiCol_TabDimmedSelected) : (tab_bar_focused ? ImGuiCol_Tab : ImGuiCol_TabDimmed));
+        TabItemBackground(display_draw_list, bb, flags, tab_col);
+        if (tab_contents_visible && (tab_bar->Flags & ImGuiTabBarFlags_DrawSelectedOverline) && style.TabBarOverlineSize > 0.0f)
         {
-            display_draw_list->AddLine(tl - ImVec2(0.5f, 0.5f), tr - ImVec2(0.5f, 0.5f), overline_col, style.TabBarOverlineSize);
+            // Might be moved to TabItemBackground() ?
+            ImVec2 tl = bb.GetTL() + ImVec2(0, 1.0f * g.CurrentDpiScale);
+            ImVec2 tr = bb.GetTR() + ImVec2(0, 1.0f * g.CurrentDpiScale);
+            ImU32 overline_col = GetColorU32(tab_bar_focused ? ImGuiCol_TabSelectedOverline : ImGuiCol_TabDimmedSelectedOverline);
+            if (style.TabRounding > 0.0f)
+            {
+                float rounding = style.TabRounding;
+                display_draw_list->PathArcToFast(tl + ImVec2(+rounding, +rounding), rounding, 7, 9);
+                display_draw_list->PathArcToFast(tr + ImVec2(-rounding, +rounding), rounding, 9, 11);
+                display_draw_list->PathStroke(overline_col, 0, style.TabBarOverlineSize);
+            }
+            else
+            {
+                display_draw_list->AddLine(tl - ImVec2(0.5f, 0.5f), tr - ImVec2(0.5f, 0.5f), overline_col, style.TabBarOverlineSize);
+            }
         }
-    }
-    RenderNavCursor(bb, id);
+        RenderNavCursor(bb, id);
 
-    // Select with right mouse button. This is so the common idiom for context menu automatically highlight the current widget.
-    const bool hovered_unblocked = IsItemHovered(ImGuiHoveredFlags_AllowWhenBlockedByPopup);
-    if (tab_bar->SelectedTabId != tab->ID && hovered_unblocked && (IsMouseClicked(1) || IsMouseReleased(1)) && !is_tab_button)
-        TabBarQueueFocus(tab_bar, tab);
+        // Select with right mouse button. This is so the common idiom for context menu automatically highlight the current widget.
+        const bool hovered_unblocked = IsItemHovered(ImGuiHoveredFlags_AllowWhenBlockedByPopup);
+        if (tab_bar->SelectedTabId != tab->ID && hovered_unblocked && (IsMouseClicked(1) || IsMouseReleased(1)) && !is_tab_button)
+            TabBarQueueFocus(tab_bar, tab);
 
-    if (tab_bar->Flags & ImGuiTabBarFlags_NoCloseWithMiddleMouseButton)
-        flags |= ImGuiTabItemFlags_NoCloseWithMiddleMouseButton;
+        if (tab_bar->Flags & ImGuiTabBarFlags_NoCloseWithMiddleMouseButton)
+            flags |= ImGuiTabItemFlags_NoCloseWithMiddleMouseButton;
 
-    // Render tab label, process close button
-    const ImGuiID close_button_id = p_open ? GetIDWithSeed("#CLOSE", NULL, id) : 0;
-    bool just_closed;
-    bool text_clipped;
-    TabItemLabelAndCloseButton(display_draw_list, bb, tab_just_unsaved ? (flags & ~ImGuiTabItemFlags_UnsavedDocument) : flags, tab_bar->FramePadding, label, id, close_button_id, tab_contents_visible, &just_closed, &text_clipped);
-    if (just_closed && p_open != NULL)
-    {
-        *p_open = false;
-        TabBarCloseTab(tab_bar, tab);
+        // Render tab label, process close button
+        const ImGuiID close_button_id = p_open ? GetIDWithSeed("#CLOSE", NULL, id) : 0;
+        bool just_closed;
+        bool text_clipped;
+        TabItemLabelAndCloseButton(display_draw_list, bb, tab_just_unsaved ? (flags & ~ImGuiTabItemFlags_UnsavedDocument) : flags, tab_bar->FramePadding, label, id, close_button_id, tab_contents_visible, &just_closed, &text_clipped);
+        if (just_closed && p_open != NULL)
+        {
+            *p_open = false;
+            TabBarCloseTab(tab_bar, tab);
+        }
+
+        // Tooltip
+        // (Won't work over the close button because ItemOverlap systems messes up with HoveredIdTimer-> seems ok)
+        // (We test IsItemHovered() to discard e.g. when another item is active or drag and drop over the tab bar, which g.HoveredId ignores)
+        // FIXME: This is a mess.
+        // FIXME: We may want disabled tab to still display the tooltip?
+        if (text_clipped && g.HoveredId == id && !held)
+            if (!(tab_bar->Flags & ImGuiTabBarFlags_NoTooltip) && !(tab->Flags & ImGuiTabItemFlags_NoTooltip))
+                SetItemTooltip("%.*s", (int)(FindRenderedTextEnd(label) - label), label);
     }
 
     // Restore main window position so user can draw there
@@ -10196,15 +10229,6 @@ bool    ImGui::TabItemEx(ImGuiTabBar* tab_bar, const char* label, bool* p_open,
         PopClipRect();
     window->DC.CursorPos = backup_main_cursor_pos;
 
-    // Tooltip
-    // (Won't work over the close button because ItemOverlap systems messes up with HoveredIdTimer-> seems ok)
-    // (We test IsItemHovered() to discard e.g. when another item is active or drag and drop over the tab bar, which g.HoveredId ignores)
-    // FIXME: This is a mess.
-    // FIXME: We may want disabled tab to still display the tooltip?
-    if (text_clipped && g.HoveredId == id && !held)
-        if (!(tab_bar->Flags & ImGuiTabBarFlags_NoTooltip) && !(tab->Flags & ImGuiTabItemFlags_NoTooltip))
-            SetItemTooltip("%.*s", (int)(FindRenderedTextEnd(label) - label), label);
-
     IM_ASSERT(!is_tab_button || !(tab_bar->SelectedTabId == tab->ID && is_tab_button)); // TabItemButton should not be selected
     if (is_tab_button)
         return pressed;