46    std::unique_ptr<QgsPointDisplacementRenderer> mRenderer;
 
   48    void blockAllSignals( 
bool block );
 
   49    void setupBlankUi( 
const QString &layerName );
 
   52    void mLabelFieldComboBox_currentIndexChanged( 
const QString &text );
 
   53    void mRendererComboBox_currentIndexChanged( 
int index );
 
   54    void mPlacementComboBox_currentIndexChanged( 
int index );
 
   55    void labelFontChanged();
 
   56    void mCircleWidthSpinBox_valueChanged( 
double d );
 
   57    void mCircleColorButton_colorChanged( 
const QColor &newColor );
 
   58    void mDistanceSpinBox_valueChanged( 
double d );
 
   59    void mDistanceUnitWidget_changed();
 
   60    void mLabelColorButton_colorChanged( 
const QColor &newColor );
 
   61    void mCircleModificationSpinBox_valueChanged( 
double d );
 
   62    void mLabelDistanceFactorSpinBox_valueChanged( 
double d );
 
   63    void mScaleDependentLabelsCheckBox_stateChanged( 
int state );
 
   64    void minLabelScaleChanged( 
double scale );
 
   65    void mRendererSettingsButton_clicked();
 
   66    void centerSymbolChanged();
 
   67    void updateRendererFromWidget();
 
 
Expression contexts are used to encapsulate the parameters around which a QgsExpression should be eva...