Docking, Style: added style.DockingNodeHasCloseButton option to hide the CloseButton() attached to each docking node. (ocornut#8933)

Author: ocornut

docs/CHANGELOG.txt

@@ -123,6 +123,8 @@ Docking+Viewports Branch:
 - DPI: Fixed obsoleted ImGuiConfigFlags_DpiEnableScaleFonts/_DpiEnableScaleViewports
   names from setting the equivalent io.ConfigDpiScaleFonts/io.ConfigDpiScaleViewports
   flag correctly (regression in 1.92).
+- Docking, Style: added style.DockingNodeHasCloseButton option to hide the
+  Close Button attached to each docking node. (#8933)
 - Backends: GLFW: improve multi-viewport behavior in tiling WMs on X11.
   Note: using GLFW backend on Linux/BSD etc. requires linking with `-lX11`.
   (#8884, #8474, #8289, #2117) [@Ikos3k, @Madman10K]

imgui.cpp

@@ -1467,6 +1467,7 @@ ImGuiStyle::ImGuiStyle()
     SeparatorTextPadding        = ImVec2(20.0f,3.f);// Horizontal offset of text from each edge of the separator + spacing on other axis. Generally small values. .y is recommended to be == FramePadding.y.
     DisplayWindowPadding        = ImVec2(19,19);    // Window position are clamped to be visible within the display area or monitors by at least this amount. Only applies to regular windows.
     DisplaySafeAreaPadding      = ImVec2(3,3);      // If you cannot see the edge of your screen (e.g. on a TV) increase the safe area padding. Covers popups/tooltips as well regular windows.
+    DockingNodeHasCloseButton   = true;             // Docking nodes have their own CloseButton() to close all docked windows.
     DockingSeparatorSize        = 2.0f;             // Thickness of resizing border between docked windows
     MouseCursorScale            = 1.0f;             // Scale software rendered mouse cursor (when io.MouseDrawCursor is enabled). May be removed later.
     AntiAliasedLines            = true;             // Enable anti-aliased lines/borders. Disable if you are really tight on CPU/GPU.
@@ -18647,7 +18648,7 @@ static void ImGui::DockNodeUpdate(ImGuiDockNode* node)
         node->HasCloseButton |= window->HasCloseButton;
         window->DockIsActive = (node->Windows.Size > 1);
     }
-    if (node_flags & ImGuiDockNodeFlags_NoCloseButton)
+    if ((node_flags & ImGuiDockNodeFlags_NoCloseButton) || !g.Style.DockingNodeHasCloseButton)
         node->HasCloseButton = false;
 
     // Bind or create host window

imgui.h

@@ -2389,6 +2389,7 @@ struct ImGuiStyle
     ImVec2      SeparatorTextPadding;       // Horizontal offset of text from each edge of the separator + spacing on other axis. Generally small values. .y is recommended to be == FramePadding.y.
     ImVec2      DisplayWindowPadding;       // Apply to regular windows: amount which we enforce to keep visible when moving near edges of your screen.
     ImVec2      DisplaySafeAreaPadding;     // Apply to every windows, menus, popups, tooltips: amount where we avoid displaying contents. Adjust if you cannot see the edges of your screen (e.g. on a TV where scaling has not been configured).
+    bool        DockingNodeHasCloseButton;  // Docking node has their own CloseButton() to close all docked windows.
     float       DockingSeparatorSize;       // Thickness of resizing border between docked windows
     float       MouseCursorScale;           // Scale software rendered mouse cursor (when io.MouseDrawCursor is enabled). We apply per-monitor DPI scaling over this scale. May be removed later.
     bool        AntiAliasedLines;           // Enable anti-aliased lines/borders. Disable if you are really tight on CPU/GPU. Latched at the beginning of the frame (copied to ImDrawList).

imgui_demo.cpp

@@ -8517,6 +8517,8 @@ void ImGui::ShowStyleEditor(ImGuiStyle* ref)
             SliderFloat("ImageBorderSize", &style.ImageBorderSize, 0.0f, 1.0f, "%.0f");
 
             SeparatorText("Docking");
+            //SetCursorPosX(GetCursorPosX() + CalcItemWidth() - GetFrameHeight());
+            Checkbox("DockingNodeHasCloseButton", &style.DockingNodeHasCloseButton);
             SliderFloat("DockingSeparatorSize", &style.DockingSeparatorSize, 0.0f, 12.0f, "%.0f");
 
             SeparatorText("Tooltips");