QGIS API Documentation  3.6.0-Noosa (5873452)
Signals | Public Member Functions | Protected Member Functions | Protected Attributes | Friends | List of all members
QgsAbstractProcessingParameterWidgetWrapper Class Referenceabstract

A widget wrapper for Processing parameter value widgets. More...

#include <qgsprocessingwidgetwrapper.h>

Inheritance diagram for QgsAbstractProcessingParameterWidgetWrapper:
Inheritance graph
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Signals

void widgetValueHasChanged (QgsAbstractProcessingParameterWidgetWrapper *wrapper)
 Emitted whenever the parameter value (as defined by the wrapped widget) is changed. More...
 

Public Member Functions

 QgsAbstractProcessingParameterWidgetWrapper (const QgsProcessingParameterDefinition *parameter=nullptr, QgsProcessingGui::WidgetType type=QgsProcessingGui::Standard, QObject *parent=nullptr)
 Constructor for QgsAbstractProcessingParameterWidgetWrapper, for the specified parameter definition and dialog type. More...
 
QgsExpressionContext createExpressionContext () const override
 This method needs to be reimplemented in all classes which implement this interface and return an expression context. More...
 
QLabel * createWrappedLabel ()
 Creates and returns a new label to accompany widgets created by the wrapper. More...
 
QWidget * createWrappedWidget (QgsProcessingContext &context)
 Creates and return a new wrapped widget which allows customization of the parameter's value. More...
 
const QgsProcessingParameterDefinitionparameterDefinition () const
 Returns the parameter definition associated with this wrapper. More...
 
QVariant parameterValue () const
 Returns the current value of the parameter. More...
 
virtual void postInitialize (const QList< QgsAbstractProcessingParameterWidgetWrapper * > &wrappers)
 Called after all wrappers have been created within a particular dialog or context, allowing the wrapper to connect to the wrappers of other, related parameters. More...
 
void registerProcessingContextGenerator (QgsProcessingContextGenerator *generator)
 Registers a Processing context generator class that will be used to retrieve a Processing context for the wrapper when required. More...
 
void setParameterValue (const QVariant &value, QgsProcessingContext &context)
 Sets the current value for the parameter. More...
 
virtual void setWidgetContext (const QgsProcessingParameterWidgetContext &context)
 Sets the context in which the Processing parameter widget is shown, e.g., the parent model algorithm, a linked map canvas, and other relevant information which allows the widget to fine-tune its behavior. More...
 
QgsProcessingGui::WidgetType type () const
 Returns the dialog type for which widgets and labels will be created by this wrapper. More...
 
const QgsProcessingParameterWidgetContextwidgetContext () const
 Returns the context in which the Processing parameter widget is shown, e.g., the parent model algorithm, a linked map canvas, and other relevant information which allows the widget to fine-tune its behavior. More...
 
QLabel * wrappedLabel ()
 Returns the current wrapped label, if any. More...
 
QWidget * wrappedWidget ()
 Returns the current wrapped widget, if any. More...
 
- Public Member Functions inherited from QgsExpressionContextGenerator
virtual ~QgsExpressionContextGenerator ()=default
 

Protected Member Functions

virtual QLabel * createLabel ()
 Creates a new label to accompany widgets created by the wrapper. More...
 
virtual QWidget * createWidget ()=0
 Creates a new widget which allows customization of the parameter's value. More...
 
virtual const QgsVectorLayerlinkedVectorLayer () const
 Returns the optional vector layer associated with this widget wrapper, or nullptr if no vector layer is applicable. More...
 
virtual void setWidgetValue (const QVariant &value, QgsProcessingContext &context)=0
 Sets the current value for the parameter to show in the widget. More...
 
virtual QVariant widgetValue () const =0
 Returns the current value of the parameter. More...
 

Protected Attributes

QgsProcessingContextGeneratormProcessingContextGenerator = nullptr
 
QgsProcessingParameterWidgetContext mWidgetContext
 

Friends

class TestProcessingGui
 

Detailed Description

A widget wrapper for Processing parameter value widgets.

Widget wrappers are used to create widgets for individual Processing parameters, and handle retrieving and setting the current value for those parameters.

Widget wrappers can be created for different dialog types, allowing different appearance and behavior of widgets depending on whether they are being created for use in a standard algorithm dialog, a batch processing dialog, or a modeler dialog.

Individual widget wrappers are not usually created directly, instead they are constructed through the central registry, via calls to QgsGui::processingGuiRegistry()->createParameterWidgetWrapper().

Since
QGIS 3.4

Definition at line 173 of file qgsprocessingwidgetwrapper.h.

Constructor & Destructor Documentation

◆ QgsAbstractProcessingParameterWidgetWrapper()

QgsAbstractProcessingParameterWidgetWrapper::QgsAbstractProcessingParameterWidgetWrapper ( const QgsProcessingParameterDefinition parameter = nullptr,
QgsProcessingGui::WidgetType  type = QgsProcessingGui::Standard,
QObject *  parent = nullptr 
)

Constructor for QgsAbstractProcessingParameterWidgetWrapper, for the specified parameter definition and dialog type.

Definition at line 69 of file qgsprocessingwidgetwrapper.cpp.

Member Function Documentation

◆ createExpressionContext()

QgsExpressionContext QgsAbstractProcessingParameterWidgetWrapper::createExpressionContext ( ) const
overridevirtual

This method needs to be reimplemented in all classes which implement this interface and return an expression context.

Since
QGIS 3.0

Implements QgsExpressionContextGenerator.

Definition at line 226 of file qgsprocessingwidgetwrapper.cpp.

◆ createLabel()

QLabel * QgsAbstractProcessingParameterWidgetWrapper::createLabel ( )
protectedvirtual

Creates a new label to accompany widgets created by the wrapper.

The caller takes ownership of the returned label. Some parameter type and dialog type combinations will return nullptr for this method. If nullptr is returned, then no label should be shown for the parameter's widget (i.e. the label is embedded inside the widget itself).

See also
createWidget()

Definition at line 171 of file qgsprocessingwidgetwrapper.cpp.

◆ createWidget()

virtual QWidget* QgsAbstractProcessingParameterWidgetWrapper::createWidget ( )
protectedpure virtual

Creates a new widget which allows customization of the parameter's value.

The caller takes ownership of the returned widget.

See also
createLabel()

◆ createWrappedLabel()

QLabel * QgsAbstractProcessingParameterWidgetWrapper::createWrappedLabel ( )

Creates and returns a new label to accompany widgets created by the wrapper.

The caller takes ownership of the returned label. Some parameter type and dialog type combinations will return nullptr for this method. If nullptr is returned, then no label should be shown for the parameter's widget (i.e. the label is embedded inside the widget itself).

The wrapped label can be retrieved at a later stage by calling wrappedLabel().

See also
createWrappedWidget()

Definition at line 119 of file qgsprocessingwidgetwrapper.cpp.

◆ createWrappedWidget()

QWidget * QgsAbstractProcessingParameterWidgetWrapper::createWrappedWidget ( QgsProcessingContext context)

Creates and return a new wrapped widget which allows customization of the parameter's value.

The caller takes ownership of the returned widget. The wrapped widget can be retrieved at a later stage by calling wrappedWidget().

The supplied context is used while initializing the widget to the parameter's default value.

See also
createWrappedLabel()

Definition at line 91 of file qgsprocessingwidgetwrapper.cpp.

◆ linkedVectorLayer()

const QgsVectorLayer * QgsAbstractProcessingParameterWidgetWrapper::linkedVectorLayer ( ) const
protectedvirtual

Returns the optional vector layer associated with this widget wrapper, or nullptr if no vector layer is applicable.

This is used to correctly generate expression contexts within the GUI, e.g. to allow expression buttons and property override buttons to correctly show the appropriate vector layer fields.

Since
QGIS 3.6

Definition at line 192 of file qgsprocessingwidgetwrapper.cpp.

◆ parameterDefinition()

const QgsProcessingParameterDefinition * QgsAbstractProcessingParameterWidgetWrapper::parameterDefinition ( ) const

Returns the parameter definition associated with this wrapper.

Definition at line 138 of file qgsprocessingwidgetwrapper.cpp.

◆ parameterValue()

QVariant QgsAbstractProcessingParameterWidgetWrapper::parameterValue ( ) const

Returns the current value of the parameter.

See also
setParameterValue()

Definition at line 158 of file qgsprocessingwidgetwrapper.cpp.

◆ postInitialize()

void QgsAbstractProcessingParameterWidgetWrapper::postInitialize ( const QList< QgsAbstractProcessingParameterWidgetWrapper * > &  wrappers)
virtual

Called after all wrappers have been created within a particular dialog or context, allowing the wrapper to connect to the wrappers of other, related parameters.

Definition at line 199 of file qgsprocessingwidgetwrapper.cpp.

◆ registerProcessingContextGenerator()

void QgsAbstractProcessingParameterWidgetWrapper::registerProcessingContextGenerator ( QgsProcessingContextGenerator generator)

Registers a Processing context generator class that will be used to retrieve a Processing context for the wrapper when required.

Definition at line 166 of file qgsprocessingwidgetwrapper.cpp.

◆ setParameterValue()

void QgsAbstractProcessingParameterWidgetWrapper::setParameterValue ( const QVariant &  value,
QgsProcessingContext context 
)

Sets the current value for the parameter.

The context argument is used to specify the wider Processing context which the current value is associated with.

See also
parameterValue()

Definition at line 143 of file qgsprocessingwidgetwrapper.cpp.

◆ setWidgetContext()

void QgsAbstractProcessingParameterWidgetWrapper::setWidgetContext ( const QgsProcessingParameterWidgetContext context)
virtual

Sets the context in which the Processing parameter widget is shown, e.g., the parent model algorithm, a linked map canvas, and other relevant information which allows the widget to fine-tune its behavior.

Subclasses should take care to call the base class method when reimplementing this method.

See also
widgetContext()

Definition at line 81 of file qgsprocessingwidgetwrapper.cpp.

◆ setWidgetValue()

virtual void QgsAbstractProcessingParameterWidgetWrapper::setWidgetValue ( const QVariant &  value,
QgsProcessingContext context 
)
protectedpure virtual

Sets the current value for the parameter to show in the widget.

The context argument is used to specify the wider Processing context which the current value is associated with.

See also
widgetValue()

◆ type()

QgsProcessingGui::WidgetType QgsAbstractProcessingParameterWidgetWrapper::type ( ) const

Returns the dialog type for which widgets and labels will be created by this wrapper.

Definition at line 76 of file qgsprocessingwidgetwrapper.cpp.

◆ widgetContext()

const QgsProcessingParameterWidgetContext & QgsAbstractProcessingParameterWidgetWrapper::widgetContext ( ) const

Returns the context in which the Processing parameter widget is shown, e.g., the parent model algorithm, a linked map canvas, and other relevant information which allows the widget to fine-tune its behavior.

See also
setWidgetContext()

Definition at line 86 of file qgsprocessingwidgetwrapper.cpp.

◆ widgetValue()

virtual QVariant QgsAbstractProcessingParameterWidgetWrapper::widgetValue ( ) const
protectedpure virtual

Returns the current value of the parameter.

See also
setWidgetValue()

◆ widgetValueHasChanged

void QgsAbstractProcessingParameterWidgetWrapper::widgetValueHasChanged ( QgsAbstractProcessingParameterWidgetWrapper wrapper)
signal

Emitted whenever the parameter value (as defined by the wrapped widget) is changed.

◆ wrappedLabel()

QLabel * QgsAbstractProcessingParameterWidgetWrapper::wrappedLabel ( )

Returns the current wrapped label, if any.

See also
createWrappedLabel()

Definition at line 133 of file qgsprocessingwidgetwrapper.cpp.

◆ wrappedWidget()

QWidget * QgsAbstractProcessingParameterWidgetWrapper::wrappedWidget ( )

Returns the current wrapped widget, if any.

See also
createWrappedWidget()

Definition at line 128 of file qgsprocessingwidgetwrapper.cpp.

Friends And Related Function Documentation

◆ TestProcessingGui

friend class TestProcessingGui
friend

Definition at line 372 of file qgsprocessingwidgetwrapper.h.

Member Data Documentation

◆ mProcessingContextGenerator

QgsProcessingContextGenerator* QgsAbstractProcessingParameterWidgetWrapper::mProcessingContextGenerator = nullptr
protected

Definition at line 353 of file qgsprocessingwidgetwrapper.h.

◆ mWidgetContext

QgsProcessingParameterWidgetContext QgsAbstractProcessingParameterWidgetWrapper::mWidgetContext
protected

Definition at line 354 of file qgsprocessingwidgetwrapper.h.


The documentation for this class was generated from the following files: