From 024fa4e506bf70a4a9ce694452d8e0470b41f8f8 Mon Sep 17 00:00:00 2001
From: lbartoletti <loic.bartoletti@oslandia.com>
Date: Fri, 7 Feb 2020 21:31:20 +0100
Subject: [PATCH 1/2] Fix identify menu when an expression is used as display
 name

---
 src/gui/qgsidentifymenu.cpp | 20 +++++++++++++++++---
 1 file changed, 17 insertions(+), 3 deletions(-)

diff --git a/src/gui/qgsidentifymenu.cpp b/src/gui/qgsidentifymenu.cpp
index af561ead1c79..c458b0a00674 100644
--- a/src/gui/qgsidentifymenu.cpp
+++ b/src/gui/qgsidentifymenu.cpp
@@ -25,6 +25,7 @@
 #include "qgslogger.h"
 #include "qgssettings.h"
 #include "qgsgui.h"
+#include "qgsexpressioncontextutils.h"
 
 //TODO 4.0 add explicitly qobject parent to constructor
 QgsIdentifyMenu::QgsIdentifyMenu( QgsMapCanvas *canvas )
@@ -282,7 +283,12 @@ void QgsIdentifyMenu::addVectorLayer( QgsVectorLayer *layer, const QList<QgsMapT
   if ( !createMenu )
   {
     // case 1
-    QString featureTitle = results[0].mFeature.attribute( layer->displayField() ).toString();
+
+    QgsExpressionContext context( QgsExpressionContextUtils::globalProjectLayerScopes( layer ) );
+    QgsExpression exp( layer->displayExpression() );
+    exp.prepare( &context );
+    context.setFeature( results[0].mFeature );
+    QString featureTitle = exp.evaluate( &context ).toString();
     if ( featureTitle.isEmpty() )
       featureTitle = QStringLiteral( "%1" ).arg( results[0].mFeature.id() );
     layerAction = new QAction( QStringLiteral( "%1 (%2)" ).arg( layer->name(), featureTitle ), this );
@@ -304,7 +310,11 @@ void QgsIdentifyMenu::addVectorLayer( QgsVectorLayer *layer, const QList<QgsMapT
       // case 2b
       else
       {
-        QString featureTitle = results[0].mFeature.attribute( layer->displayField() ).toString();
+        QgsExpressionContext context( QgsExpressionContextUtils::globalProjectLayerScopes( layer ) );
+        QgsExpression exp( layer->displayExpression() );
+        exp.prepare( &context );
+        context.setFeature( results[0].mFeature );
+        QString featureTitle = exp.evaluate( &context ).toString();
         if ( featureTitle.isEmpty() )
           featureTitle = QStringLiteral( "%1" ).arg( results[0].mFeature.id() );
         layerMenu = new QMenu( QStringLiteral( "%1 (%2)" ).arg( layer->name(), featureTitle ), this );
@@ -364,7 +374,11 @@ void QgsIdentifyMenu::addVectorLayer( QgsVectorLayer *layer, const QList<QgsMapT
     }
 
     // feature title
-    QString featureTitle = result.mFeature.attribute( layer->displayField() ).toString();
+    QgsExpressionContext context( QgsExpressionContextUtils::globalProjectLayerScopes( layer ) );
+    QgsExpression exp( layer->displayExpression() );
+    exp.prepare( &context );
+    context.setFeature( result.mFeature );
+    QString featureTitle = exp.evaluate( &context ).toString();
     if ( featureTitle.isEmpty() )
       featureTitle = QStringLiteral( "%1" ).arg( result.mFeature.id() );
 

From 618020af86a1f52dd5d942bdd0f4b793be662275 Mon Sep 17 00:00:00 2001
From: lbartoletti <loic.bartoletti@oslandia.com>
Date: Mon, 10 Feb 2020 08:50:20 +0100
Subject: [PATCH 2/2] avoid code duplication

---
 src/gui/qgsidentifymenu.cpp | 16 ++++------------
 1 file changed, 4 insertions(+), 12 deletions(-)

diff --git a/src/gui/qgsidentifymenu.cpp b/src/gui/qgsidentifymenu.cpp
index c458b0a00674..5bf3caaccf0e 100644
--- a/src/gui/qgsidentifymenu.cpp
+++ b/src/gui/qgsidentifymenu.cpp
@@ -279,15 +279,14 @@ void QgsIdentifyMenu::addVectorLayer( QgsVectorLayer *layer, const QList<QgsMapT
     }
   }
 
+  QgsExpressionContext context( QgsExpressionContextUtils::globalProjectLayerScopes( layer ) );
+  QgsExpression exp( layer->displayExpression() );
+  exp.prepare( &context );
+  context.setFeature( results[0].mFeature );
   // use a menu only if actions will be listed
   if ( !createMenu )
   {
     // case 1
-
-    QgsExpressionContext context( QgsExpressionContextUtils::globalProjectLayerScopes( layer ) );
-    QgsExpression exp( layer->displayExpression() );
-    exp.prepare( &context );
-    context.setFeature( results[0].mFeature );
     QString featureTitle = exp.evaluate( &context ).toString();
     if ( featureTitle.isEmpty() )
       featureTitle = QStringLiteral( "%1" ).arg( results[0].mFeature.id() );
@@ -310,10 +309,6 @@ void QgsIdentifyMenu::addVectorLayer( QgsVectorLayer *layer, const QList<QgsMapT
       // case 2b
       else
       {
-        QgsExpressionContext context( QgsExpressionContextUtils::globalProjectLayerScopes( layer ) );
-        QgsExpression exp( layer->displayExpression() );
-        exp.prepare( &context );
-        context.setFeature( results[0].mFeature );
         QString featureTitle = exp.evaluate( &context ).toString();
         if ( featureTitle.isEmpty() )
           featureTitle = QStringLiteral( "%1" ).arg( results[0].mFeature.id() );
@@ -374,9 +369,6 @@ void QgsIdentifyMenu::addVectorLayer( QgsVectorLayer *layer, const QList<QgsMapT
     }
 
     // feature title
-    QgsExpressionContext context( QgsExpressionContextUtils::globalProjectLayerScopes( layer ) );
-    QgsExpression exp( layer->displayExpression() );
-    exp.prepare( &context );
     context.setFeature( result.mFeature );
     QString featureTitle = exp.evaluate( &context ).toString();
     if ( featureTitle.isEmpty() )