From 74f42f1778404cf1658d102cafd57bfa6d504a28 Mon Sep 17 00:00:00 2001
From: qPCR4vir <arielvina@yahoo.es>
Date: Mon, 9 Sep 2019 19:53:03 +0200
Subject: [PATCH] new feature "fit_width_to_header caption text" for a new
 header with width=0

(cherry picked from commit 23efa5088d742a48e7ad07f273e84bcf50c2d979)
---
 source/gui/widgets/listbox.cpp | 25 ++++++++++++++++++++++++-
 1 file changed, 24 insertions(+), 1 deletion(-)

diff --git a/source/gui/widgets/listbox.cpp b/source/gui/widgets/listbox.cpp
index 41347095..0e72f7db 100644
--- a/source/gui/widgets/listbox.cpp
+++ b/source/gui/widgets/listbox.cpp
@@ -167,7 +167,7 @@ namespace nana
 					
 					column(column&& other):
 						caption(std::move(other.caption)),
-						width_px(other.width_px),
+                        width_px(other.width_px),
 						range_width_px(other.range_width_px),
 						visible_state(other.visible_state),
 						index(other.index),
@@ -184,7 +184,13 @@ namespace nana
 						index(pos),
 						ess_(ess)
 					{
+					    if (px == 0)
+                        {
+					        fit_width_to_header();
+                        }
 					}
+
+					void fit_width_to_header();
 				private:
 					/// The definition is provided after essence
 					void _m_refresh() noexcept;
@@ -2881,6 +2887,23 @@ namespace nana
 				return max_px;
 			}
 
+			void es_header::column::fit_width_to_header()
+            {
+			    std::cout<< "Column: " << to_utf8(caption) ;
+                std::unique_ptr<paint::graphics> graph_helper;
+                auto graph = ess_->graph;
+                if (graph->empty())
+                {
+                    //Creates a helper if widget graph is empty(when its size is 0).
+                    graph_helper.reset(new paint::graphics{ nana::size{ 5, 5 } });
+                    graph_helper->typeface(ess_->graph->typeface());
+                    graph = graph_helper.get();
+                }
+                width_px = ess_->scheme_ptr->text_margin * 2;	    //margin at left/right end.
+
+                width_px += graph->text_extent_size(caption).width;
+            }
+
 			//es_header::column member functions
 			void es_header::column::_m_refresh() noexcept
 			{