[gui] Introduce dialog to add function files, allowing users to choose whether to store functions in a .py file (current behavior) or in the QGIS project

src/gui/CMakeLists.txt

@@ -588,6 +588,7 @@ set(QGIS_GUI_SRCS
   qgsdockwidget.cpp
   qgsencodingfiledialog.cpp
   qgserrordialog.cpp
+  qgsexpressionaddfunctionfiledialog.cpp
   qgsexpressionbuilderdialog.cpp
   qgsexpressionbuilderwidget.cpp
   qgsexpressionfinder.cpp
@@ -852,6 +853,7 @@ set(QGIS_GUI_HDRS
   qgsdoublevalidator.h
   qgsencodingfiledialog.h
   qgserrordialog.h
+  qgsexpressionaddfunctionfiledialog.h
   qgsexpressionbuilderdialog.h
   qgsexpressionstoredialog.h
   qgsexpressionbuilderwidget.h

src/gui/qgsexpressionaddfunctionfiledialog.cpp

@@ -0,0 +1,58 @@
+/***************************************************************************
+    qgsexpressionaddfunctionfiledialog.cpp
+    ---------------------
+    begin                : May 2024
+    copyright            : (C) 2024 by Germán Carrillo
+    email                : german at opengis dot ch
+ ***************************************************************************
+ *                                                                         *
+ *   This program is free software; you can redistribute it and/or modify  *
+ *   it under the terms of the GNU General Public License as published by  *
+ *   the Free Software Foundation; either version 2 of the License, or     *
+ *   (at your option) any later version.                                   *
+ *                                                                         *
+ ***************************************************************************/
+
+
+#include <QPushButton>
+#include <QStandardItemModel>
+#include "qgsexpressionaddfunctionfiledialog.h"
+
+QgsExpressionAddFunctionFileDialog::QgsExpressionAddFunctionFileDialog( const bool enableProjectFunctions, QWidget *parent )
+  : QDialog( parent )
+{
+  setupUi( this );
+  cboFileOptions->addItem( QStringLiteral( "Function file" ) );
+  cboFileOptions->addItem( QStringLiteral( "Project functions" ), QStringLiteral( "project" ) );
+
+  // Disable project functions (they should be created only once)
+  if ( !enableProjectFunctions )
+  {
+    QStandardItem *item = qobject_cast<QStandardItemModel *>( cboFileOptions->model() )->item( 1 );
+    item->setFlags( item->flags() & ~Qt::ItemIsEnabled );
+  }
+
+  connect( cboFileOptions, qOverload<int>( &QComboBox::currentIndexChanged ), this, &QgsExpressionAddFunctionFileDialog::cboFileOptions_currentIndexChanged );
+  connect( txtNewFileName, &QLineEdit::textChanged, this, [ = ]( const QString & ) { updateOkButtonStatus(); } );
+
+  updateOkButtonStatus();
+}
+
+void QgsExpressionAddFunctionFileDialog::cboFileOptions_currentIndexChanged( int )
+{
+  bool projectSelected = cboFileOptions->currentData() == "project";
+  lblNewFileName->setVisible( !projectSelected );
+  txtNewFileName->setVisible( !projectSelected );
+  updateOkButtonStatus();
+}
+
+void QgsExpressionAddFunctionFileDialog::updateOkButtonStatus()
+{
+  QPushButton *okBtn = buttonBox->button( QDialogButtonBox::StandardButton::Ok );
+  okBtn->setEnabled( true );
+
+  if ( cboFileOptions->currentData() != "project" )
+  {
+    okBtn->setEnabled( !txtNewFileName->text().trimmed().isEmpty() );
+  }
+}

src/gui/qgsexpressionaddfunctionfiledialog.h

@@ -0,0 +1,52 @@
+/***************************************************************************
+    qgsexpressionaddfunctionfiledialog.h
+    ---------------------
+    begin                : May 2024
+    copyright            : (C) 2024 by Germán Carrillo
+    email                : german at opengis dot ch
+ ***************************************************************************
+ *                                                                         *
+ *   This program is free software; you can redistribute it and/or modify  *
+ *   it under the terms of the GNU General Public License as published by  *
+ *   the Free Software Foundation; either version 2 of the License, or     *
+ *   (at your option) any later version.                                   *
+ *                                                                         *
+ ***************************************************************************/
+
+#ifndef QGSEXPRESSIONADDFUNCTIONFILEDIALOG_H
+#define QGSEXPRESSIONADDFUNCTIONFILEDIALOG_H
+
+#include "qgis_gui.h"
+#include <QDialog>
+#include "ui_qgsexpressionaddfunctionfiledialogbase.h"
+
+
+/**
+ * \ingroup gui
+ * \brief A dialog to select whether to create a function file or project functions.
+ * \since QGIS 3.40
+ */
+class GUI_EXPORT QgsExpressionAddFunctionFileDialog : public QDialog, private Ui::QgsExpressionAddFunctionFileDialogBase
+{
+    Q_OBJECT
+  public:
+    QgsExpressionAddFunctionFileDialog( const bool enableProjectFunctions, QWidget *parent );
+
+    /**
+     * Returns whether user has selected to create project functions
+     */
+    bool createProjectFunctions() const {return cboFileOptions->currentData() == "project";};
+
+    /**
+     * Returns the new file name
+     */
+    QString fileName() {return txtNewFileName->text().trimmed();};
+
+  private slots:
+    void cboFileOptions_currentIndexChanged( int );
+
+  private:
+    void updateOkButtonStatus();
+};
+
+#endif // QGSEXPRESSIONADDFUNCTIONFILEDIALOG_H

src/gui/qgsexpressionbuilderwidget.cpp

@@ -17,7 +17,6 @@
 #include <QFile>
 #include <QTextStream>
 #include <QDir>
-#include <QInputDialog>
 #include <QComboBox>
 #include <QGraphicsOpacityEffect>
 #include <QPropertyAnimation>
@@ -49,6 +48,7 @@
 #include "qgsexpressionstoredialog.h"
 #include "qgsexpressiontreeview.h"
 #include "qgscodeeditorwidget.h"
+#include "qgsexpressionaddfunctionfiledialog.h"
 
 
 bool formatterCanProvideAvailableValues( QgsVectorLayer *layer, const QString &fieldName )
@@ -428,7 +428,7 @@ void QgsExpressionBuilderWidget::updateFunctionFileList( const QString &path )
   mProject->readEntry( QStringLiteral( "ExpressionFunctions" ), QStringLiteral( "/pythonCode" ), QString(), &ok );
   if ( ok )
   {
-    QListWidgetItem *item = new QListWidgetItem( QgsApplication::getThemeIcon( QStringLiteral( "console/iconTabEditorConsole.svg" ) ), DEFAULT_PROJECT_FUNCTIONS_ITEM_NAME );
+    QListWidgetItem *item = new QListWidgetItem( QgsApplication::getThemeIcon( QStringLiteral( "mIconQgsProjectFile.svg" ) ), DEFAULT_PROJECT_FUNCTIONS_ITEM_NAME );
     item->setData( Qt::UserRole, QStringLiteral( "project" ) );
     cmbFileNames->insertItem( 0, item );
   }
@@ -466,15 +466,19 @@ void QgsExpressionBuilderWidget::newFunctionFile( const QString &fileName )
 
 void QgsExpressionBuilderWidget::btnNewFile_pressed()
 {
-  bool ok;
+  // If a project has an entry for functions, then we should
-  QString text = QInputDialog::getText( this, tr( "New File" ),
+  // already have a 'Project functions' item in the file list.
-                                        tr( "New file name:" ), QLineEdit::Normal,
+  // Since only one item should correspond to 'Project functions',
-                                        QString(), &ok );
+  // we'll disable this option in the 'add function file' dialog.
-  if ( ok && !text.isEmpty() )
+  bool ok = false;
+  mProject->readEntry( QStringLiteral( "ExpressionFunctions" ), QStringLiteral( "/pythonCode" ), QString(), &ok );
+
+  QgsExpressionAddFunctionFileDialog dlg {!ok, this};
+  if ( dlg.exec() == QDialog::DialogCode::Accepted )
   {
-    if ( text.contains( QStringLiteral( "project" ) ) )
+    if ( dlg.createProjectFunctions() )
     {
-      QListWidgetItem *item = new QListWidgetItem( QgsApplication::getThemeIcon( QStringLiteral( "console/iconTabEditorConsole.svg" ) ), DEFAULT_PROJECT_FUNCTIONS_ITEM_NAME );
+      QListWidgetItem *item = new QListWidgetItem( QgsApplication::getThemeIcon( QStringLiteral( "mIconQgsProjectFile.svg" ) ), DEFAULT_PROJECT_FUNCTIONS_ITEM_NAME );
       item->setData( Qt::UserRole, QStringLiteral( "project" ) );
       cmbFileNames->insertItem( 0, item );
       cmbFileNames->setCurrentRow( 0 );
@@ -486,9 +490,8 @@ void QgsExpressionBuilderWidget::btnNewFile_pressed()
     }
     else
     {
-      newFunctionFile( text );
+      newFunctionFile( dlg.fileName() );
     }
-
     btnRemoveFile->setEnabled( cmbFileNames->count() > 0 );
   }
 }

src/ui/qgsexpressionaddfunctionfiledialogbase.ui

@@ -0,0 +1,84 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<ui version="4.0">
+ <class>QgsExpressionAddFunctionFileDialogBase</class>
+ <widget class="QDialog" name="QgsExpressionAddFunctionFileDialogBase">
+  <property name="geometry">
+   <rect>
+    <x>0</x>
+    <y>0</y>
+    <width>265</width>
+    <height>135</height>
+   </rect>
+  </property>
+  <property name="windowTitle">
+   <string>Add Function File</string>
+  </property>
+  <layout class="QGridLayout" name="gridLayout">
+   <item row="0" column="0">
+    <widget class="QLabel" name="label">
+     <property name="text">
+      <string>Create</string>
+     </property>
+    </widget>
+   </item>
+   <item row="1" column="1">
+    <widget class="QLineEdit" name="txtNewFileName"/>
+   </item>
+   <item row="0" column="1">
+    <widget class="QComboBox" name="cboFileOptions"/>
+   </item>
+   <item row="2" column="1">
+    <widget class="QDialogButtonBox" name="buttonBox">
+     <property name="orientation">
+      <enum>Qt::Horizontal</enum>
+     </property>
+     <property name="standardButtons">
+      <set>QDialogButtonBox::Cancel|QDialogButtonBox::Ok</set>
+     </property>
+    </widget>
+   </item>
+   <item row="1" column="0">
+    <widget class="QLabel" name="lblNewFileName">
+     <property name="text">
+      <string>File name</string>
+     </property>
+    </widget>
+   </item>
+  </layout>
+ </widget>
+ <resources/>
+ <connections>
+  <connection>
+   <sender>buttonBox</sender>
+   <signal>accepted()</signal>
+   <receiver>QgsExpressionAddFunctionFileDialogBase</receiver>
+   <slot>accept()</slot>
+   <hints>
+    <hint type="sourcelabel">
+     <x>248</x>
+     <y>254</y>
+    </hint>
+    <hint type="destinationlabel">
+     <x>157</x>
+     <y>274</y>
+    </hint>
+   </hints>
+  </connection>
+  <connection>
+   <sender>buttonBox</sender>
+   <signal>rejected()</signal>
+   <receiver>QgsExpressionAddFunctionFileDialogBase</receiver>
+   <slot>reject()</slot>
+   <hints>
+    <hint type="sourcelabel">
+     <x>316</x>
+     <y>260</y>
+    </hint>
+    <hint type="destinationlabel">
+     <x>286</x>
+     <y>274</y>
+    </hint>
+   </hints>
+  </connection>
+ </connections>
+</ui>

src/ui/ui_qgsexpressionaddfunctionfiledialogbase.h

@@ -0,0 +1,96 @@
+/********************************************************************************
+** Form generated from reading UI file 'qgsexpressionaddfunctionfiledialogbase.ui'
+**
+** Created by: Qt User Interface Compiler version 5.15.3
+**
+** WARNING! All changes made in this file will be lost when recompiling UI file!
+********************************************************************************/
+
+#ifndef QGSEXPRESSIONADDFUNCTIONFILEDIALOGBASE_H
+#define QGSEXPRESSIONADDFUNCTIONFILEDIALOGBASE_H
+
+#include <QtCore/QVariant>
+#include <QtWidgets/QApplication>
+#include <QtWidgets/QComboBox>
+#include <QtWidgets/QDialog>
+#include <QtWidgets/QDialogButtonBox>
+#include <QtWidgets/QGridLayout>
+#include <QtWidgets/QLabel>
+#include <QtWidgets/QLineEdit>
+
+QT_BEGIN_NAMESPACE
+
+class Ui_QgsAddFunctionFileDialogBase
+{
+  public:
+    QGridLayout *gridLayout;
+    QLabel *label;
+    QComboBox *cboFileOptions;
+    QLabel *lblNewFileName;
+    QDialogButtonBox *buttonBox;
+    QLineEdit *txtNewFileName;
+
+    void setupUi( QDialog *QgsAddFunctionFileDialogBase )
+    {
+      if ( QgsAddFunctionFileDialogBase->objectName().isEmpty() )
+        QgsAddFunctionFileDialogBase->setObjectName( QString::fromUtf8( "QgsAddFunctionFileDialogBase" ) );
+      QgsAddFunctionFileDialogBase->resize( 277, 132 );
+      gridLayout = new QGridLayout( QgsAddFunctionFileDialogBase );
+      gridLayout->setObjectName( QString::fromUtf8( "gridLayout" ) );
+      label = new QLabel( QgsAddFunctionFileDialogBase );
+      label->setObjectName( QString::fromUtf8( "label" ) );
+
+      gridLayout->addWidget( label, 0, 0, 1, 1 );
+
+      cboFileOptions = new QComboBox( QgsAddFunctionFileDialogBase );
+      cboFileOptions->addItem( QString() );
+      cboFileOptions->addItem( QString() );
+      cboFileOptions->setObjectName( QString::fromUtf8( "cboFileOptions" ) );
+
+      gridLayout->addWidget( cboFileOptions, 0, 1, 1, 1 );
+
+      lblNewFileName = new QLabel( QgsAddFunctionFileDialogBase );
+      lblNewFileName->setObjectName( QString::fromUtf8( "lblNewFileName" ) );
+
+      gridLayout->addWidget( lblNewFileName, 1, 0, 1, 1 );
+
+      buttonBox = new QDialogButtonBox( QgsAddFunctionFileDialogBase );
+      buttonBox->setObjectName( QString::fromUtf8( "buttonBox" ) );
+      buttonBox->setOrientation( Qt::Horizontal );
+      buttonBox->setStandardButtons( QDialogButtonBox::Cancel | QDialogButtonBox::Ok );
+
+      gridLayout->addWidget( buttonBox, 2, 0, 1, 2 );
+
+      txtNewFileName = new QLineEdit( QgsAddFunctionFileDialogBase );
+      txtNewFileName->setObjectName( QString::fromUtf8( "txtNewFileName" ) );
+
+      gridLayout->addWidget( txtNewFileName, 1, 1, 1, 1 );
+
+
+      retranslateUi( QgsAddFunctionFileDialogBase );
+      QObject::connect( buttonBox, SIGNAL( accepted() ), QgsAddFunctionFileDialogBase, SLOT( accept() ) );
+      QObject::connect( buttonBox, SIGNAL( rejected() ), QgsAddFunctionFileDialogBase, SLOT( reject() ) );
+
+      QMetaObject::connectSlotsByName( QgsAddFunctionFileDialogBase );
+    } // setupUi
+
+    void retranslateUi( QDialog *QgsAddFunctionFileDialogBase )
+    {
+      QgsAddFunctionFileDialogBase->setWindowTitle( QCoreApplication::translate( "QgsAddFunctionFileDialogBase", "Add Function File", nullptr ) );
+      label->setText( QCoreApplication::translate( "QgsAddFunctionFileDialogBase", "Create", nullptr ) );
+      cboFileOptions->setItemText( 0, QCoreApplication::translate( "QgsAddFunctionFileDialogBase", "Function file", nullptr ) );
+      cboFileOptions->setItemText( 1, QCoreApplication::translate( "QgsAddFunctionFileDialogBase", "Project functions", nullptr ) );
+
+      lblNewFileName->setText( QCoreApplication::translate( "QgsAddFunctionFileDialogBase", "File name", nullptr ) );
+    } // retranslateUi
+
+};
+
+namespace Ui
+{
+  class QgsAddFunctionFileDialogBase: public Ui_QgsAddFunctionFileDialogBase {};
+} // namespace Ui
+
+QT_END_NAMESPACE
+
+#endif // QGSEXPRESSIONADDFUNCTIONFILEDIALOGBASE_H