From d74389f9303ef0052a1541476ad026a4d7b3c572 Mon Sep 17 00:00:00 2001
From: Vadim Zeitlin <vadim@wxwidgets.org>
Date: Fri, 1 May 2020 03:29:32 +0200
Subject: [PATCH] Fix WXGetManuallySetWidth() for columns using
 wxCOL_WIDTH_DEFAULT

Columns without any explicitly specified width still shouldn't be shrunk
down to 0 size by UpdateColumnSizes(), so handle them as if they were
created using wxDVC_DEFAULT_WIDTH instead -- which is what their actual
width is/would be.

This is a better fix than the one in 0c90ea40c3 (Don't auto-resize
wxDataViewCtrl columns below their initial size, 2019-10-03) and that
commit can be reverted now, as will be done soon.

See #18343.
---
 include/wx/generic/dataview.h | 2 +-
 src/generic/datavgen.cpp      | 9 +++++++++
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/include/wx/generic/dataview.h b/include/wx/generic/dataview.h
index 4c932cfd1c..247a30d253 100644
--- a/include/wx/generic/dataview.h
+++ b/include/wx/generic/dataview.h
@@ -154,7 +154,7 @@ public:
     // user interactively.
     void WXOnResize(int width);
 
-    int WXGetManuallySetWidth() const { return m_manuallySetWidth; }
+    int WXGetManuallySetWidth() const;
 
 private:
     // common part of all ctors
diff --git a/src/generic/datavgen.cpp b/src/generic/datavgen.cpp
index bce892416b..0e8689765d 100644
--- a/src/generic/datavgen.cpp
+++ b/src/generic/datavgen.cpp
@@ -217,6 +217,15 @@ void wxDataViewColumn::WXOnResize(int width)
     m_owner->OnColumnResized();
 }
 
+int wxDataViewColumn::WXGetManuallySetWidth() const
+{
+    // Note that we need to return valid value even if no width was initially
+    // specified, as otherwise the last column created without any explicit
+    // width could be reduced to nothing by UpdateColumnSizes() when the
+    // control is shrunk.
+    return DoGetEffectiveWidth(m_manuallySetWidth);
+}
+
 void wxDataViewColumn::UpdateDisplay()
 {
     if (m_owner)