[FEATURE] Substitution list support for labeling

Adds the ability to specify a list of text substitutes to make
which apply to label text. Eg abbrevating street types.

Users can export and import lists of substitutes to make
reuse and sharing easier.

python/core/qgspallabeling.sip

@@ -464,6 +464,11 @@ class QgsPalLayerSettings
     QPainter::CompositionMode blendMode;
     QColor previewBkgrdColor;
 
+    //! Substitution collection for automatic text substitution with labels
+    QgsStringReplacementCollection substitutions;
+    //! True if substitutions should be applied
+    bool useSubstitutions;
+
     //-- text formatting
 
     QString wrapChar;

python/core/qgsstringutils.sip

@@ -1,3 +1,115 @@
+
+
+/** \ingroup core
+ * \class QgsStringReplacement
+ * \brief A representation of a single string replacement.
+ * \note Added in version 3.0
+ */
+
+class QgsStringReplacement
+{
+%TypeHeaderCode
+#include <qgsstringutils.h>
+%End
+  public:
+
+    /** Constructor for QgsStringReplacement.
+     * @param match string to match
+     * @param replacement string to replace match with
+     * @param caseSensitive set to true for a case sensitive match
+     * @param wholeWordOnly set to true to match complete words only, or false to allow partial word matches
+     */
+    QgsStringReplacement( const QString& match,
+                          const QString& replacement,
+                          bool caseSensitive = false,
+                          bool wholeWordOnly = false );
+
+    //! Returns the string matched by this object
+    QString match() const;
+
+    //! Returns the string to replace matches with
+    QString replacement() const;
+
+    //! Returns true if match is case sensitive
+    bool caseSensitive() const;
+
+    //! Returns true if match only applies to whole words, or false if partial word matches are permitted
+    bool wholeWordOnly() const;
+
+    /** Processes a given input string, applying any valid replacements which should be made.
+     * @param input input string
+     * @returns input string with any matches replaced by replacement string
+     */
+    QString process( const QString& input ) const;
+
+    bool operator==( const QgsStringReplacement& other );
+
+    /** Returns a map of the replacement properties.
+     * @see fromProperties()
+     */
+    QgsStringMap properties() const;
+
+    /** Creates a new QgsStringReplacement from an encoded properties map.
+     * @see properties()
+     */
+    static QgsStringReplacement fromProperties( const QgsStringMap& properties );
+
+};
+
+
+/** \ingroup core
+ * \class QgsStringReplacementCollection
+ * \brief A collection of string replacements (specified using QgsStringReplacement objects).
+ * \note Added in version 3.0
+ */
+
+class QgsStringReplacementCollection
+{
+%TypeHeaderCode
+#include <qgsstringutils.h>
+%End
+  public:
+
+    /** Constructor for QgsStringReplacementCollection
+     * @param replacements initial list of string replacements
+     */
+    QgsStringReplacementCollection( const QList< QgsStringReplacement >& replacements = QList< QgsStringReplacement >() );
+
+    /** Returns the list of string replacements in this collection.
+     * @see setReplacements()
+     */
+    QList< QgsStringReplacement > replacements() const;
+
+    /** Sets the list of string replacements in this collection.
+     * @param replacements list of string replacements to apply. Replacements are applied in the
+     * order they are specified here.
+     * @see replacements()
+     */
+    void setReplacements( const QList< QgsStringReplacement >& replacements );
+
+    /** Processes a given input string, applying any valid replacements which should be made
+     * using QgsStringReplacement objects contained by this collection. Replacements
+     * are made in order of the QgsStringReplacement objects contained in the collection.
+     * @param input input string
+     * @returns input string with any matches replaced by replacement string
+     */
+    QString process( const QString& input ) const;
+
+    /** Writes the collection state to an XML element.
+     * @param elem target DOM element
+     * @param doc DOM document
+     * @see readXml()
+     */
+    void writeXml( QDomElement& elem, QDomDocument& doc ) const;
+
+    /** Reads the collection state from an XML element.
+     * @param elem DOM element
+     * @see writeXml()
+     */
+    void readXml( const QDomElement& elem );
+};
+
+
 /** \ingroup core
  * \class QgsStringUtils
  * \brief Utility functions for working with strings.

src/app/CMakeLists.txt

@@ -114,6 +114,7 @@ SET(QGIS_APP_SRCS
   qgsrelationadddlg.cpp
   qgsselectbyformdialog.cpp
   qgsstatisticalsummarydockwidget.cpp
+  qgssubstitutionlistwidget.cpp
   qgstextannotationdialog.cpp
   qgssnappingdialog.cpp
   qgssvgannotationdialog.cpp
@@ -290,6 +291,7 @@ SET (QGIS_APP_MOC_HDRS
   qgssnappingdialog.h
   qgssponsors.h
   qgsstatisticalsummarydockwidget.h
+  qgssubstitutionlistwidget.h
   qgssvgannotationdialog.h
   qgstextannotationdialog.h
   qgstipgui.h

src/app/qgslabelinggui.cpp

@@ -34,6 +34,7 @@
 #include "qgssvgselectorwidget.h"
 #include "qgsvectorlayerlabeling.h"
 #include "qgslogger.h"
+#include "qgssubstitutionlistwidget.h"
 
 #include <QCheckBox>
 #include <QSettings>
@@ -137,6 +138,7 @@ QgsLabelingGui::QgsLabelingGui( QgsVectorLayer* layer, QgsMapCanvas* mapCanvas,
   connect( mShadowTranspSlider, SIGNAL( valueChanged( int ) ), mShadowTranspSpnBx, SLOT( setValue( int ) ) );
   connect( mShadowTranspSpnBx, SIGNAL( valueChanged( int ) ), mShadowTranspSlider, SLOT( setValue( int ) ) );
   connect( mLimitLabelChkBox, SIGNAL( toggled( bool ) ), mLimitLabelSpinBox, SLOT( setEnabled( bool ) ) );
+  connect( mCheckBoxSubstituteText, SIGNAL( toggled( bool ) ), mToolButtonConfigureSubstitutes, SLOT( setEnabled( bool ) ) );
 
   //connections to prevent users removing all line placement positions
   connect( chkLineAbove, SIGNAL( toggled( bool ) ), this, SLOT( updateLinePlacementOptions() ) );
@@ -466,7 +468,8 @@ QgsLabelingGui::QgsLabelingGui( QgsVectorLayer* layer, QgsMapCanvas* mapCanvas,
   << radPolygonPerimeter
   << radPolygonPerimeterCurved
   << radPredefinedOrder
-  << mFieldExpressionWidget;
+  << mFieldExpressionWidget
+  << mCheckBoxSubstituteText;
   connectValueChanged( widgets, SLOT( updatePreview() ) );
 
   connect( mQuadrantBtnGrp, SIGNAL( buttonClicked( int ) ), this, SLOT( updatePreview() ) );
@@ -623,6 +626,8 @@ void QgsLabelingGui::init()
   // set the current field or add the current expression to the bottom of the list
   mFieldExpressionWidget->setRow( -1 );
   mFieldExpressionWidget->setField( lyr.fieldName );
+  mCheckBoxSubstituteText->setChecked( lyr.useSubstitutions );
+  mSubstitutions = lyr.substitutions;
 
   // populate placement options
   mCentroidRadioWhole->setChecked( lyr.centroidWhole );
@@ -1013,6 +1018,8 @@ QgsPalLayerSettings QgsLabelingGui::layerSettings()
   lyr.scaleVisibility = mScaleBasedVisibilityChkBx->isChecked();
   lyr.scaleMin = mScaleBasedVisibilityMinSpnBx->value();
   lyr.scaleMax = mScaleBasedVisibilityMaxSpnBx->value();
+  lyr.useSubstitutions = mCheckBoxSubstituteText->isChecked();
+  lyr.substitutions = mSubstitutions;
 
   // buffer
   lyr.bufferDraw = mBufferDrawChkBx->isChecked();
@@ -1973,6 +1980,12 @@ void QgsLabelingGui::updateLinePlacementOptions()
   }
 }
 
+void QgsLabelingGui::onSubstitutionsChanged( const QgsStringReplacementCollection& substitutions )
+{
+  mSubstitutions = substitutions;
+  emit widgetChanged();
+}
+
 void QgsLabelingGui::updateSvgWidgets( const QString& svgPath )
 {
   if ( mShapeSVGPathLineEdit->text() != svgPath )
@@ -2099,6 +2112,28 @@ void QgsLabelingGui::on_mChkNoObstacle_toggled( bool active )
   mObstaclePriorityFrame->setEnabled( active );
 }
 
+void QgsLabelingGui::on_mToolButtonConfigureSubstitutes_clicked()
+{
+  QgsPanelWidget* panel = QgsPanelWidget::findParentPanel( this );
+  if ( panel && panel->dockMode() )
+  {
+    QgsSubstitutionListWidget* widget = new QgsSubstitutionListWidget( panel );
+    widget->setPanelTitle( tr( "Substitutions" ) );
+    widget->setSubstitutions( mSubstitutions );
+    connect( widget, SIGNAL( substitutionsChanged( QgsStringReplacementCollection ) ), this, SLOT( onSubstitutionsChanged( QgsStringReplacementCollection ) ) );
+    panel->openPanel( widget );
+    return;
+  }
+
+  QgsSubstitutionListDialog dlg( this );
+  dlg.setSubstitutions( mSubstitutions );
+  if ( dlg.exec() == QDialog::Accepted )
+  {
+    mSubstitutions = dlg.substitutions();
+    emit widgetChanged();
+  }
+}
+
 void QgsLabelingGui::showBackgroundRadius( bool show )
 {
   mShapeRadiusLabel->setVisible( show );

src/app/qgslabelinggui.h

@@ -21,6 +21,7 @@
 #include <QDialog>
 #include <QFontDatabase>
 #include <ui_qgslabelingguibase.h>
+#include "qgsstringutils.h"
 
 class QgsVectorLayer;
 class QgsMapCanvas;
@@ -94,6 +95,8 @@ class APP_EXPORT QgsLabelingGui : public QWidget, private Ui::QgsLabelingGuiBase
     void on_mDirectSymbRightToolBtn_clicked();
     void on_mChkNoObstacle_toggled( bool active );
 
+    void on_mToolButtonConfigureSubstitutes_clicked();
+
   protected:
     void blockInitSignals( bool block );
     void blockFontChangeSignals( bool blk );
@@ -133,6 +136,8 @@ class APP_EXPORT QgsLabelingGui : public QWidget, private Ui::QgsLabelingGuiBase
 
     bool mLoadSvgParams;
 
+    QgsStringReplacementCollection mSubstitutions;
+
     void enableDataDefinedAlignment( bool enable );
 
     QgsExpressionContext createExpressionContext() const override;
@@ -143,6 +148,7 @@ class APP_EXPORT QgsLabelingGui : public QWidget, private Ui::QgsLabelingGuiBase
     void showBackgroundPenStyle( bool show );
     void on_mShapeSVGPathLineEdit_textChanged( const QString& text );
     void updateLinePlacementOptions();
+    void onSubstitutionsChanged( const QgsStringReplacementCollection& substitutions );
 };
 
 #endif