From 30b2919c8125ddfbcad460d5e7b3fdd6b04f7410 Mon Sep 17 00:00:00 2001
From: Nyall Dawson <nyall.dawson@gmail.com>
Date: Tue, 17 Dec 2019 09:05:44 +1000
Subject: [PATCH] Make custom projection validation button work on proj < 6

---
 src/app/qgscustomprojectiondialog.cpp | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/src/app/qgscustomprojectiondialog.cpp b/src/app/qgscustomprojectiondialog.cpp
index 334e4b404eaa..115fd9ddd7a2 100644
--- a/src/app/qgscustomprojectiondialog.cpp
+++ b/src/app/qgscustomprojectiondialog.cpp
@@ -515,7 +515,23 @@ void QgsCustomProjectionDialog::validateCurrent()
   proj_log_func( context, nullptr, nullptr );
   proj_context_destroy( context );
   context = nullptr;
+#else
+  projCtx pContext = pj_ctx_alloc();
+  projPJ proj = pj_init_plus_ctx( pContext, projDef.toLocal8Bit().data() );
 
+  if ( proj )
+  {
+    QMessageBox::information( this, tr( "Custom Coordinate Reference System" ),
+                              tr( "This proj projection definition is valid." ) );
+  }
+  else
+  {
+    QMessageBox::warning( this, tr( "Custom Coordinate Reference System" ),
+                          tr( "This proj projection definition is not valid" ) );
+  }
+
+  pj_free( proj );
+  pj_ctx_free( pContext );
 #endif
 }