Add a new dialog for selecting file encoding, QgsEncodingSelectionDialog

Can be used to prompt users for a file encoding choice

python/gui/qgsencodingfiledialog.sip

@@ -49,6 +49,46 @@ Returns true if the user clicked 'Cancel All'
 
 };
 
+class QgsEncodingSelectionDialog: QDialog
+{
+%Docstring
+ A dialog which presents the user with a choice of file encodings.
+.. versionadded:: 3.0
+*
+%End
+
+%TypeHeaderCode
+#include "qgsencodingfiledialog.h"
+%End
+  public:
+
+    QgsEncodingSelectionDialog( QWidget *parent /TransferThis/ = 0,
+                                const QString &caption = QString(), const QString &encoding = QString(),
+                                Qt::WindowFlags flags = Qt::WindowFlags() );
+%Docstring
+ Constructor for QgsEncodingSelectionDialog.
+
+ If ``caption`` is set, it will be used as the caption within the dialog.
+
+ The ``encoding`` argument can be used to specify the encoding initially selected in the dialog.
+%End
+
+    QString encoding() const;
+%Docstring
+ Returns the encoding selected within the dialog.
+.. seealso:: setEncoding()
+ :rtype: str
+%End
+
+    void setEncoding( const QString &encoding );
+%Docstring
+ Sets the ``encoding`` selected within the dialog.
+ see encoding()
+%End
+
+};
+
+
 /************************************************************************
  * This file has been generated automatically from                      *
  *                                                                      *

src/gui/qgsencodingfiledialog.cpp

@@ -24,6 +24,7 @@
 #include <QLabel>
 #include <QLayout>
 #include <QTextCodec>
+#include <QDialogButtonBox>
 
 QgsEncodingFileDialog::QgsEncodingFileDialog( QWidget *parent,
     const QString &caption, const QString &directory,
@@ -102,3 +103,63 @@ void QgsEncodingFileDialog::pbnCancelAll_clicked()
   // Now, continue as the user clicked the cancel button
   reject();
 }
+
+QgsEncodingSelectionDialog::QgsEncodingSelectionDialog( QWidget *parent, const QString &caption, const QString &encoding, Qt::WindowFlags flags )
+  : QDialog( parent, flags )
+{
+  QString c = caption;
+  if ( c.isEmpty() )
+    c = tr( "Encoding" );
+
+  setWindowTitle( tr( "Select Encoding" ) );
+
+  QVBoxLayout *layout = new QVBoxLayout();
+  layout->setMargin( 6 );
+
+  mEncodingComboBox = new QComboBox( this );
+  QLabel *l = new QLabel( c, this );
+
+  QHBoxLayout *hLayout = new QHBoxLayout();
+  hLayout->addWidget( l );
+  hLayout->addWidget( mEncodingComboBox, 1 );
+  layout->addLayout( hLayout );
+
+  QDialogButtonBox *buttonBox = new QDialogButtonBox( QDialogButtonBox::Ok | QDialogButtonBox::Cancel,
+      Qt::Horizontal, this );
+  buttonBox->button( QDialogButtonBox::Ok )->setDefault( true );
+  connect( buttonBox, &QDialogButtonBox::rejected, this, &QDialog::reject );
+  connect( buttonBox, &QDialogButtonBox::accepted, this, &QDialog::accept );
+  layout->addWidget( buttonBox );
+  setLayout( layout );
+
+  mEncodingComboBox->addItems( QgsVectorDataProvider::availableEncodings() );
+
+  // Use default encoding if none supplied
+  QString enc = encoding;
+  if ( encoding.isEmpty() )
+  {
+    QgsSettings settings;
+    enc = settings.value( QStringLiteral( "UI/encoding" ), "System" ).toString();
+  }
+
+  setEncoding( enc );
+}
+
+QString QgsEncodingSelectionDialog::encoding() const
+{
+  return mEncodingComboBox->currentText();
+}
+
+void QgsEncodingSelectionDialog::setEncoding( const QString &encoding )
+{
+  // The specified decoding is added if not existing alread, and then set current.
+  // This should select it.
+
+  int encindex = mEncodingComboBox->findText( encoding );
+  if ( encindex < 0 )
+  {
+    mEncodingComboBox->insertItem( 0, encoding );
+    encindex = 0;
+  }
+  mEncodingComboBox->setCurrentIndex( encindex );
+}

src/gui/qgsencodingfiledialog.h

@@ -61,4 +61,45 @@ class GUI_EXPORT QgsEncodingFileDialog: public QFileDialog
     bool mCancelAll;
 };
 
+/**
+ * \ingroup gui
+ * A dialog which presents the user with a choice of file encodings.
+ * \since QGIS 3.0
+ **/
+class GUI_EXPORT QgsEncodingSelectionDialog: public QDialog
+{
+    Q_OBJECT
+
+  public:
+
+    /**
+     * Constructor for QgsEncodingSelectionDialog.
+     *
+     * If \a caption is set, it will be used as the caption within the dialog.
+     *
+     * The \a encoding argument can be used to specify the encoding initially selected in the dialog.
+     */
+    QgsEncodingSelectionDialog( QWidget *parent SIP_TRANSFERTHIS = nullptr,
+                                const QString &caption = QString(), const QString &encoding = QString(),
+                                Qt::WindowFlags flags = Qt::WindowFlags() );
+
+    /**
+     * Returns the encoding selected within the dialog.
+     * \see setEncoding()
+     */
+    QString encoding() const;
+
+    /**
+     * Sets the \a encoding selected within the dialog.
+     * see encoding()
+     */
+    void setEncoding( const QString &encoding );
+
+  private:
+
+    QComboBox *mEncodingComboBox = nullptr;
+
+};
+
+
 #endif

tests/src/python/CMakeLists.txt

@@ -48,6 +48,7 @@ ADD_PYTHON_TEST(PyQgsDelimitedTextProvider test_qgsdelimitedtextprovider.py)
 ADD_PYTHON_TEST(PyQgsDistanceArea test_qgsdistancearea.py)
 ADD_PYTHON_TEST(PyQgsEditWidgets test_qgseditwidgets.py)
 ADD_PYTHON_TEST(PyQgsEllipsoidUtils test_qgsellipsoidutils.py)
+ADD_PYTHON_TEST(PyQgsEncodingSelectionDialog test_qgsencodingselectiondialog.py)
 ADD_PYTHON_TEST(PyQgsExpression test_qgsexpression.py)
 ADD_PYTHON_TEST(PyQgsExpressionBuilderWidget test_qgsexpressionbuilderwidget.py)
 ADD_PYTHON_TEST(PyQgsExpressionLineEdit test_qgsexpressionlineedit.py)

tests/src/python/test_qgsencodingselectiondialog.py

@@ -0,0 +1,38 @@
+# -*- coding: utf-8 -*-
+"""QGIS Unit tests for QgsEncodingSelectionDialog
+
+.. note:: 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.
+"""
+__author__ = 'Nyall Dawson'
+__date__ = '21/11/2017'
+__copyright__ = 'Copyright 2017, The QGIS Project'
+# This will get replaced with a git SHA1 when you do a git archive
+__revision__ = '$Format:%H$'
+
+import qgis  # NOQA
+
+from qgis.gui import QgsEncodingSelectionDialog
+
+from qgis.testing import start_app, unittest
+
+start_app()
+
+
+class TestQgsEncodingSelectionDialog(unittest.TestCase):
+
+    def testGettersSetters(self):
+        """ test dialog getters/setters """
+        dlg = qgis.gui.QgsEncodingSelectionDialog(encoding='UTF-16')
+        self.assertEqual(dlg.encoding(), 'UTF-16')
+        dlg.setEncoding('UTF-8')
+        self.assertEqual(dlg.encoding(), 'UTF-8')
+        # custom encoding option
+        dlg.setEncoding('trisolarian')
+        self.assertEqual(dlg.encoding(), 'trisolarian')
+
+
+if __name__ == '__main__':
+    unittest.main()