Move processing algorithm configuration widget to gui library

This way we can also use all the fancy widgets like a QgsExpressionLineEdit.

python/core/processing/qgsprocessingalgorithm.sip.in

@@ -349,12 +349,6 @@ If an algorithm subclass implements a custom parameters widget, a copy of this w
 should be constructed and returned by this method.
 The base class implementation returns None, which indicates that an autogenerated
 parameters widget should be used.
-%End
-
-    virtual QgsProcessingAlgorithmConfigurationWidget *createModelerWidget() const /Factory/;
-%Docstring
-If an algorithm subclass implements a configuration widget for the algorithm itself,
-a new instance of this widget should be returned by this method.
 %End
 
     QgsExpressionContext createExpressionContext( const QVariantMap &parameters,

python/core/processing/qgsprocessingalgorithmconfigurationwidget.sip.in

@@ -9,19 +9,68 @@
 
 
 
+
+
+
+
 class QgsProcessingAlgorithmConfigurationWidget : QWidget
 {
+%Docstring
+A configuration widget for processing algorithms allows to provide additional
+configuration options directly on algorithm level, in addition to parameters.
+
+.. versionadded:: 3.2
+%End
 
 %TypeHeaderCode
 #include "qgsprocessingalgorithmconfigurationwidget.h"
 %End
   public:
+
     QgsProcessingAlgorithmConfigurationWidget( QWidget *parent = 0 );
+%Docstring
+Creates a new QgsProcessingAlgorithmConfigurationWidget
+%End
     virtual ~QgsProcessingAlgorithmConfigurationWidget();
+
     virtual QVariantMap configuration() const = 0;
+%Docstring
+Read the current configuration from this widget.
+%End
+
     virtual void setConfiguration( const QVariantMap &configuration ) = 0;
+%Docstring
+Set the configuration which this widget should represent.
+%End
+};
+
+
+class QgsProcessingAlgorithmConfigurationWidgetFactory
+{
+%Docstring
+Interface base class for factories for algorithm configuration widgets.
+
+.. versionadded:: 3.2
+%End
+
+%TypeHeaderCode
+#include "qgsprocessingalgorithmconfigurationwidget.h"
+%End
+  public:
+    virtual ~QgsProcessingAlgorithmConfigurationWidgetFactory();
+
+    virtual QgsProcessingAlgorithmConfigurationWidget *create( QgsProcessingAlgorithm *algorithm ) const = 0 /Factory/;
+%Docstring
+Create a new configuration widget for ``algorithm``.
+%End
+
+    virtual bool canCreateFor( QgsProcessingAlgorithm *algorithm ) const = 0;
+%Docstring
+Check if this factory can create widgets for ``algorithm``.
+%End
 };
 
+
 /************************************************************************
  * This file has been generated automatically from                      *
  *                                                                      *

python/core/processing/qgsprocessingregistry.sip.in

@@ -143,6 +143,29 @@ Return a list with all known parameter types.
 .. versionadded:: 3.2
 %End
 
+    void addAlgorithmConfigurationWidgetFactory( QgsProcessingAlgorithmConfigurationWidgetFactory *factory /Transfer/ );
+%Docstring
+Add a new configuration widget factory for customized algorithm configuration
+widgets. Ownership is taken.
+
+.. versionadded:: 3.2
+%End
+
+    void removeAlgorithmConfigurationWidgetFactory( QgsProcessingAlgorithmConfigurationWidgetFactory *factory );
+%Docstring
+Remove a configuration widget factory for customized algorithm configuration
+widgets.
+
+.. versionadded:: 3.2
+%End
+
+    QgsProcessingAlgorithmConfigurationWidget *algorithmConfigurationWidget( QgsProcessingAlgorithm *algorithm ) const;
+%Docstring
+ algorithmConfigurationWidget
+@param algorithm
+@return
+%End
+
 
   signals:
 

python/gui/gui_auto.sip

@@ -312,4 +312,5 @@
 %Include layout/qgslayoutviewtoolzoom.sip
 %Include locator/qgslocatorwidget.sip
 %Include processing/qgsprocessingalgorithmdialogbase.sip
+%Include processing/qgsprocessingconfigurationwidgets.sip
 %Include qgsadvanceddigitizingcanvasitem.sip

python/gui/processing/qgsprocessingconfigurationwidgets.sip.in

@@ -0,0 +1,61 @@
+/************************************************************************
+ * This file has been generated automatically from                      *
+ *                                                                      *
+ * src/gui/processing/qgsprocessingconfigurationwidgets.h               *
+ *                                                                      *
+ * Do not edit manually ! Edit header and run scripts/sipify.pl again   *
+ ************************************************************************/
+
+
+
+
+
+
+class QgsProcessingConfigurationWidgets
+{
+%Docstring
+This class is responsible for the management of processing widgets which
+QGIS internally.
+
+Standalone applications that require to show configuration widgets for processing
+algorithms will need to execute the following code to have the configuration
+interfaces available.
+
+.. code-block:: python
+
+     # At startup time
+     QgsApplicationProcessingConfigurationWidgets.initialize()
+
+     # At exit time
+     QgsApplicationProcessingConfigurationWidgets.cleanup()
+%End
+
+%TypeHeaderCode
+#include "qgsprocessingconfigurationwidgets.h"
+%End
+  public:
+
+    static void initialize();
+%Docstring
+Initialize native configuration widgets.
+%End
+
+    static void cleanup();
+%Docstring
+Cleanup native configuration widgets.
+%End
+
+  private:
+    QgsProcessingConfigurationWidgets();
+};
+
+
+
+
+/************************************************************************
+ * This file has been generated automatically from                      *
+ *                                                                      *
+ * src/gui/processing/qgsprocessingconfigurationwidgets.h               *
+ *                                                                      *
+ * Do not edit manually ! Edit header and run scripts/sipify.pl again   *
+ ************************************************************************/

python/plugins/processing/modeler/ModelerParametersDialog.py

@@ -36,6 +36,7 @@
                                  QHBoxLayout, QWidget)
 
 from qgis.core import (Qgis,
+                       QgsApplication,
                        QgsProcessingParameterDefinition,
                        QgsProcessingParameterPoint,
                        QgsProcessingParameterExtent,
@@ -118,7 +119,7 @@ def setupUi(self):
         line.setFrameShape(QFrame.HLine)
         line.setFrameShadow(QFrame.Sunken)
         self.verticalLayout.addWidget(line)
-        self.algorithmItem = self._alg.createModelerWidget()
+        self.algorithmItem = QgsApplication.instance().processingRegistry().algorithmConfigurationWidget(self._alg)
         if self.configuration:
             self.algorithmItem.setConfiguration(self.configuration)
         self.verticalLayout.addWidget(self.algorithmItem)
@@ -330,6 +331,7 @@ def createAlgorithm(self):
                     output.setChildId(alg.childId())
                     output.setChildOutputName(dest.name())
                     outputs[name] = output
+
         alg.setModelOutputs(outputs)
 
         selectedOptions = self.dependenciesPanel.selectedoptions

src/analysis/CMakeLists.txt

@@ -140,7 +140,6 @@ SET(QGIS_ANALYSIS_MOC_HDRS
   network/qgsvectorlayerdirector.h
 
   processing/qgsalgorithmfiledownloader.h
-  processing/qgsalgorithmfilter.h
 
   vector/geometry_checker/qgsfeaturepool.h
   vector/geometry_checker/qgsgeometrychecker.h

src/analysis/processing/qgsalgorithmfilter.cpp

@@ -18,12 +18,6 @@
 #include "qgsalgorithmfilter.h"
 #include "qgsapplication.h"
 
-#include <QLabel>
-#include <QGridLayout>
-#include <QTableWidget>
-#include <QHeaderView>
-#include <QToolButton>
-
 ///@cond PRIVATE
 
 QString QgsFilterAlgorithm::name() const
@@ -66,11 +60,6 @@ QgsFilterAlgorithm *QgsFilterAlgorithm::createInstance() const
   return new QgsFilterAlgorithm();
 }
 
-QgsProcessingAlgorithmConfigurationWidget *QgsFilterAlgorithm::createModelerWidget() const
-{
-  return new QgsFilterAlgorithmConfigurationWidget();
-}
-
 QgsFilterAlgorithm::~QgsFilterAlgorithm()
 {
   qDeleteAll( mOutputs );
@@ -93,60 +82,6 @@ void QgsFilterAlgorithm::initAlgorithm( const QVariantMap &configuration )
 }
 
 
-QgsFilterAlgorithmConfigurationWidget::QgsFilterAlgorithmConfigurationWidget( QWidget *parent )
-  : QgsProcessingAlgorithmConfigurationWidget( parent )
-{
-  setContentsMargins( 0, 0, 0, 0 );
-
-  mOutputExpressionWidget = new QTableWidget();
-  mOutputExpressionWidget->setColumnCount( 2 );
-  mOutputExpressionWidget->setHorizontalHeaderItem( 0, new QTableWidgetItem( tr( "Output Name" ) ) );
-  mOutputExpressionWidget->setHorizontalHeaderItem( 1, new QTableWidgetItem( tr( "Filter Expression" ) ) );
-  mOutputExpressionWidget->horizontalHeader()->setStretchLastSection( true );
-  QGridLayout *layout = new QGridLayout();
-  setLayout( layout );
-
-  layout->addWidget( new QLabel( tr( "Outputs and filters" ) ), 0, 0, 1, 2 );
-  layout->addWidget( mOutputExpressionWidget, 1, 0, 4, 1 );
-  QToolButton *addOutputButton = new QToolButton();
-  addOutputButton->setIcon( QgsApplication::getThemeIcon( QStringLiteral( "/mActionAddLayer.svg" ) ) );
-  addOutputButton->setText( tr( "Add Output" ) );
-
-  QToolButton *removeOutputButton = new QToolButton();
-  removeOutputButton->setIcon( QgsApplication::getThemeIcon( QStringLiteral( "/mActionRemoveLayer.svg" ) ) );
-  removeOutputButton->setToolTip( tr( "Remove Selected Outputs" ) );
-
-  layout->addWidget( addOutputButton, 2, 1, 1, 1 );
-  layout->addWidget( removeOutputButton, 3, 1, 1, 1 );
-
-  connect( addOutputButton, &QToolButton::clicked, this, &QgsFilterAlgorithmConfigurationWidget::addOutput );
-  connect( removeOutputButton, &QToolButton::clicked, this, &QgsFilterAlgorithmConfigurationWidget::removeSelectedOutputs );
-
-  connect( mOutputExpressionWidget->selectionModel(), &QItemSelectionModel::selectionChanged, [removeOutputButton, this]
-  {
-    removeOutputButton->setEnabled( !mOutputExpressionWidget->selectionModel()->selectedIndexes().isEmpty() );
-  } );
-}
-
-QVariantMap QgsFilterAlgorithmConfigurationWidget::configuration() const
-{
-  QVariantList outputs;
-
-  for ( int i = 0; i < mOutputExpressionWidget->rowCount(); ++i )
-  {
-    QVariantMap output;
-    output.insert( QStringLiteral( "name" ), mOutputExpressionWidget->item( i, 0 )->text() );
-    output.insert( QStringLiteral( "expression" ), mOutputExpressionWidget->item( i, 1 )->text() );
-    outputs.append( output );
-  }
-
-  QVariantMap map;
-  map.insert( "outputs", outputs );
-
-  return map;
-}
-
-
 QVariantMap QgsFilterAlgorithm::processAlgorithm( const QVariantMap &parameters, QgsProcessingContext &context, QgsProcessingFeedback *feedback )
 {
   std::unique_ptr< QgsFeatureSource > source( parameterAsSource( parameters, QStringLiteral( "INPUT" ), context ) );
@@ -195,53 +130,3 @@ QVariantMap QgsFilterAlgorithm::processAlgorithm( const QVariantMap &parameters,
   return outputs;
 }
 
-
-void QgsFilterAlgorithmConfigurationWidget::setConfiguration( const QVariantMap &configuration )
-{
-  mOutputExpressionWidget->setRowCount( 0 );
-  int currentRow = 0;
-  const QVariantList outputs = configuration.value( "outputs" ).toList();
-
-  for ( const QVariant &outputvar : outputs )
-  {
-    const QVariantMap output = outputvar.toMap();
-    mOutputExpressionWidget->insertRow( currentRow );
-    mOutputExpressionWidget->setItem( currentRow, 0, new QTableWidgetItem( output.value( "name" ).toString() ) );
-    mOutputExpressionWidget->setItem( currentRow, 1, new QTableWidgetItem( output.value( "expression" ).toString() ) );
-
-    currentRow++;
-  }
-
-  if ( outputs.isEmpty() )
-    addOutput();
-}
-
-void QgsFilterAlgorithmConfigurationWidget::removeSelectedOutputs()
-{
-  QItemSelection selection( mOutputExpressionWidget->selectionModel()->selection() );
-
-  QList<int> rows;
-  const QModelIndexList indexes = selection.indexes();
-  for ( const QModelIndex &index : indexes )
-  {
-    rows.append( index.row() );
-  }
-
-  qSort( rows );
-
-  int prev = -1;
-  for ( int i = rows.count() - 1; i >= 0; i -= 1 )
-  {
-    int current = rows[i];
-    if ( current != prev )
-    {
-      mOutputExpressionWidget->removeRow( current );
-      prev = current;
-    }
-  }
-}
-
-void QgsFilterAlgorithmConfigurationWidget::addOutput()
-{
-  mOutputExpressionWidget->setRowCount( mOutputExpressionWidget->rowCount() + 1 );
-}