add API to allow adding processing parameters to classification methods

qgis · Dec 4, 2019 · b078370 · b078370
1 parent f341b34
commit b078370
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Showing 2 changed files with 82 additions and 11 deletions.
diff --git a/src/core/classification/qgsclassificationmethod.cpp b/src/core/classification/qgsclassificationmethod.cpp
@@ -39,7 +39,7 @@ QList<double> QgsClassificationMethod::rangesToBreaks( const QList<QgsClassifica
 QgsClassificationMethod::QgsClassificationMethod( MethodProperties properties, int codeComplexity )
   : mFlags( properties )
   , mCodeComplexity( codeComplexity )
-  , mLabelFormat( QStringLiteral( "%1 - %2 " ) )
+  , mLabelFormat( QStringLiteral( "%1 - %2" ) )
 {
 }
 
@@ -161,6 +161,42 @@ QString QgsClassificationMethod::formatNumber( double value ) const
   }
 }
 
+void QgsClassificationMethod::addParameter( QgsProcessingParameterDefinition *definition )
+{
+  mParameters.append( definition );
+}
+
+QVariant QgsClassificationMethod::parameterValue( const QString &name ) const
+{
+  const QgsProcessingParameterDefinition *def = parameterDefinition( name );
+  if ( def )
+    return mParameterValues.value( name, def->defaultValue() );
+  else
+    return mParameterValues.value( name );
+}
+
+const QgsProcessingParameterDefinition *QgsClassificationMethod::parameterDefinition( const QString &parameterName ) const
+{
+  for ( const QgsProcessingParameterDefinition *def : mParameters )
+  {
+    if ( def->name() == parameterName )
+      return def;
+  }
+  return nullptr;
+}
+
+void QgsClassificationMethod::setParameterValues( const QVariantMap &values )
+{
+  mParameterValues = values;
+  for ( const QString &paramName : mParameterValues.keys() ) // todo is this ok?
+  {
+    if ( !parameterDefinition( paramName ) )
+    {
+      QgsMessageLog::logMessage( name(), QObject::tr( "Parameter %1 does not exist in the method" ).arg( paramName ) );
+    }
+  }
+}
+
 QList<QgsClassificationRange> QgsClassificationMethod::classes( const QgsVectorLayer *layer, const QString &expression, int nclasses )
 {
   if ( expression.isEmpty() )
@@ -173,6 +209,7 @@ QList<QgsClassificationRange> QgsClassificationMethod::classes( const QgsVectorL
   double minimum;
   double maximum;
 
+
   int fieldIndex = layer->fields().indexFromName( expression );
 
   bool ok;
@@ -192,7 +229,7 @@ QList<QgsClassificationRange> QgsClassificationMethod::classes( const QgsVectorL
     maximum = layer->maximumValue( fieldIndex ).toDouble();
   }
 
-  // get the breaks
+  // get the breaks, minimum and maximum might be updated by implementation
   QList<double> breaks = calculateBreaks( minimum, maximum, values, nclasses );
   breaks.insert( 0, minimum );
   // create classes

diff --git a/src/core/classification/qgsclassificationmethod.h b/src/core/classification/qgsclassificationmethod.h
@@ -110,7 +110,7 @@ class CORE_EXPORT QgsClassificationMethod SIP_ABSTRACT
     enum MethodProperty
     {
       NoFlag                 = 0,       //!< No flag
-      ValuesNotRequired      = 1 << 1,  //!< Values are not required to calculate, min/max are enough
+      ValuesNotRequired      = 1 << 1,  //!< Deprecated since QGIS 3.12
       SymmetricModeAvailable = 1 << 2,  //!< This allows using symmetric classification
     };
     Q_DECLARE_FLAGS( MethodProperties, MethodProperty )
@@ -159,14 +159,15 @@ class CORE_EXPORT QgsClassificationMethod SIP_ABSTRACT
     //! Reads extra information to apply it to the method
     virtual void readXml( const QDomElement &element, const QgsReadWriteContext &context ) {Q_UNUSED( element ); Q_UNUSED( context )}
 
-    // *******************
-    // non-virtual methods
-
     /**
      * Returns if the method requires values to calculate the classes
      * If not, bounds are sufficient
      */
-    bool valuesRequired() const {return !mFlags.testFlag( ValuesNotRequired );}
+    virtual bool valuesRequired() const {return true;}
+
+
+    // *******************
+    // non-virtual methods
 
     //! Code complexity as the exponent in Big O notation
     int codeComplexity() const {return mCodeComplexity;}
@@ -270,6 +271,24 @@ class CORE_EXPORT QgsClassificationMethod SIP_ABSTRACT
      */
     QString labelForRange( const QgsRendererRange &range, ClassPosition position = Inner ) const;
 
+    /**
+     * Get parameter from its id
+     * \since QGIS 3.12
+     */
+    const QgsProcessingParameterDefinition *parameterDefinition( const QString &parameterName ) const;
+
+    /**
+     * List of parameters
+     * \since QGIS 3.12
+     */
+    const QgsProcessingParameterDefinitions parameterDefinitions() const {return mParameters;}
+
+    /**
+     * Set values of the additional parameters
+     * \since QGIS 3.12
+     */
+    void setParameterValues( const QVariantMap &values );
+
 
 
     static const int MAX_PRECISION;
@@ -283,20 +302,32 @@ class CORE_EXPORT QgsClassificationMethod SIP_ABSTRACT
     //! Format the number according to label properties
     QString formatNumber( double value ) const;
 
+    /**
+     * Add parameter
+     * \since QGIS 3.12
+     */
+    void addParameter( QgsProcessingParameterDefinition *definition );
+
+    /**
+     * Get the parameter value
+     * \see setParameterValues
+     * \since QGIS 3.12
+     */
+    QVariant parameterValue( const QString &name ) const;
+
   private:
 
     /**
-     * Calculate the breaks, should be reimplemented, values might be an empty list
+     * Calculate the breaks, should be reimplemented, values might be an empty list if they are not required
      * If the symmetric mode is available, the implementation is responsible of applying the symmetry
      * The maximum value is expected to be added at the end of the list, but not the minimum
      */
-    virtual QList<double> calculateBreaks( double minimum, double maximum,
+    virtual QList<double> calculateBreaks( double &minimum, double &maximum,
                                            const QList<double> &values, int nclasses ) = 0;
 
     //! This is called after calculating the breaks or restoring from XML, so it can rely on private variables
     virtual QString valueToLabel( double value ) const {return formatNumber( value );}
 
-
     //! Create a list of ranges from a list of classes
     QList<QgsClassificationRange> breaksToClasses( const QList<double> &breaks ) const;
 
@@ -313,10 +344,13 @@ class CORE_EXPORT QgsClassificationMethod SIP_ABSTRACT
     bool mLabelTrimTrailingZeroes = true;
     QString mLabelFormat;
 
-
     // values used to manage number formatting - precision and trailing zeroes
     double mLabelNumberScale = 1.0;
     QString mLabelNumberSuffix;
+
+    //! additional parameters
+    QgsProcessingParameterDefinitions mParameters;
+    QVariantMap mParameterValues;
 };
 
 Q_DECLARE_OPERATORS_FOR_FLAGS( QgsClassificationMethod::MethodProperties )