QGIS API Documentation  3.16.0-Hannover (43b64b13f3)
Public Member Functions | Static Public Member Functions | List of all members
QgsProcessingParameterFileDestination Class Reference

A generic file based destination parameter, for specifying the destination path for a file (non-map layer) created by the algorithm. More...

#include <qgsprocessingparameters.h>

Inheritance diagram for QgsProcessingParameterFileDestination:
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Public Member Functions

 QgsProcessingParameterFileDestination (const QString &name, const QString &description=QString(), const QString &fileFilter=QString(), const QVariant &defaultValue=QVariant(), bool optional=false, bool createByDefault=true)
 Constructor for QgsProcessingParameterFileDestination. More...
 
QString asPythonString (QgsProcessing::PythonOutputType outputType=QgsProcessing::PythonQgsProcessingAlgorithmSubclass) const override
 Returns the parameter definition as a Python command which can be used within a Python Processing script. More...
 
bool checkValueIsAcceptable (const QVariant &input, QgsProcessingContext *context=nullptr) const override
 Checks whether the specified input value is acceptable for the parameter. More...
 
QgsProcessingParameterDefinitionclone () const override
 Creates a clone of the parameter definition. More...
 
QString createFileFilter () const override
 This method needs to be reimplemented in all classes which implement this interface and return a file filter. More...
 
QString defaultFileExtension () const override
 Returns the default file extension for destination file paths associated with this parameter. More...
 
QString fileFilter () const
 Returns the file filter string for file destinations compatible with this parameter. More...
 
bool fromVariantMap (const QVariantMap &map) override
 Restores this parameter to a QVariantMap. More...
 
void setFileFilter (const QString &filter)
 Sets the file filter string for file destinations compatible with this parameter. More...
 
QgsProcessingOutputDefinitiontoOutputDefinition () const override
 Returns a new QgsProcessingOutputDefinition corresponding to the definition of the destination parameter. More...
 
QVariantMap toVariantMap () const override
 Saves this parameter to a QVariantMap. More...
 
QString type () const override
 Unique parameter type name. More...
 
QString valueAsPythonString (const QVariant &value, QgsProcessingContext &context) const override
 Returns a string version of the parameter input value, which is suitable for use as an input parameter value when running an algorithm directly from a Python command. More...
 
- Public Member Functions inherited from QgsProcessingDestinationParameter
 QgsProcessingDestinationParameter (const QString &name, const QString &description=QString(), const QVariant &defaultValue=QVariant(), bool optional=false, bool createByDefault=true)
 Constructor for QgsProcessingDestinationParameter. More...
 
bool createByDefault () const
 Returns true if the destination should be created by default. More...
 
virtual QString generateTemporaryDestination () const
 Generates a temporary destination value for this parameter. More...
 
bool isDestination () const override
 Returns true if this parameter represents a file or layer destination, e.g. More...
 
virtual bool isSupportedOutputValue (const QVariant &value, QgsProcessingContext &context, QString &error) const
 Tests whether a value is a supported value for this parameter. More...
 
void setCreateByDefault (bool createByDefault)
 Sets whether the destination should be created by default. More...
 
void setSupportsNonFileBasedOutput (bool supportsNonFileBasedOutput)
 Sets whether the destination parameter supports non filed-based outputs, such as memory layers or direct database outputs. More...
 
bool supportsNonFileBasedOutput () const
 Returns true if the destination parameter supports non filed-based outputs, such as memory layers or direct database outputs. More...
 
- Public Member Functions inherited from QgsProcessingParameterDefinition
 QgsProcessingParameterDefinition (const QString &name, const QString &description=QString(), const QVariant &defaultValue=QVariant(), bool optional=false, const QString &help=QString())
 Constructor for QgsProcessingParameterDefinition. More...
 
virtual ~QgsProcessingParameterDefinition ()=default
 
QStringList additionalExpressionContextVariables () const
 Returns a list of additional expression context variables which are available for use when evaluating this parameter. More...
 
QgsProcessingAlgorithmalgorithm () const
 Returns a pointer to the algorithm which owns this parameter. More...
 
virtual QString asScriptCode () const
 Returns the parameter definition encoded in a string which can be used within a Processing script. More...
 
QVariant defaultValue () const
 Returns the default value for the parameter. More...
 
virtual QStringList dependsOnOtherParameters () const
 Returns a list of other parameter names on which this parameter is dependent (e.g. More...
 
QString description () const
 Returns the description for the parameter. More...
 
QString dynamicLayerParameterName () const
 Returns the name of the parameter for a layer linked to a dynamic parameter, or an empty string if this is not set. More...
 
QgsPropertyDefinition dynamicPropertyDefinition () const
 Returns the property definition for dynamic properties. More...
 
Flags flags () const
 Returns any flags associated with the parameter. More...
 
QString help () const
 Returns the help for the parameter. More...
 
bool isDynamic () const
 Returns true if the parameter supports is dynamic, and can support data-defined values (i.e. More...
 
QVariantMap & metadata ()
 Returns the parameter's freeform metadata. More...
 
QVariantMap metadata () const
 Returns the parameter's freeform metadata. More...
 
QString name () const
 Returns the name of the parameter. More...
 
QgsProcessingProviderprovider () const
 Returns a pointer to the provider for the algorithm which owns this parameter. More...
 
void setAdditionalExpressionContextVariables (const QStringList &variables)
 Sets a list of additional expression context variables which are available for use when evaluating this parameter. More...
 
void setDefaultValue (const QVariant &value)
 Sets the default value for the parameter. More...
 
void setDescription (const QString &description)
 Sets the description for the parameter. More...
 
void setDynamicLayerParameterName (const QString &name)
 Sets the name for the parameter for a layer linked to a dynamic parameter, or an empty string if this is not set. More...
 
void setDynamicPropertyDefinition (const QgsPropertyDefinition &definition)
 Sets the property definition for dynamic properties. More...
 
void setFlags (Flags flags)
 Sets the flags associated with the parameter. More...
 
void setHelp (const QString &help)
 Sets the help for the parameter. More...
 
void setIsDynamic (bool dynamic)
 Sets whether the parameter is dynamic, and can support data-defined values (i.e. More...
 
void setMetadata (const QVariantMap &metadata)
 Sets the parameter's freeform metadata. More...
 
void setName (const QString &name)
 Sets the name of the parameter. More...
 
virtual QString toolTip () const
 Returns a formatted tooltip for use with the parameter, which gives helpful information like parameter description, ID, and extra content like default values (depending on parameter type). More...
 
- Public Member Functions inherited from QgsFileFilterGenerator
virtual ~QgsFileFilterGenerator ()=default
 

Static Public Member Functions

static QgsProcessingParameterFileDestinationfromScriptCode (const QString &name, const QString &description, bool isOptional, const QString &definition)
 Creates a new parameter using the definition from a script code. More...
 
static QString typeName ()
 Returns the type name for the parameter class. More...
 

Additional Inherited Members

- Public Types inherited from QgsProcessingParameterDefinition
enum  Flag { FlagAdvanced = 1 << 1, FlagHidden = 1 << 2, FlagOptional = 1 << 3, FlagIsModelOutput = 1 << 4 }
 Parameter flags. More...
 
- Protected Member Functions inherited from QgsProcessingDestinationParameter
QgsProcessingProvideroriginalProvider () const
 Original (source) provider which this parameter has been derived from. More...
 
- Protected Attributes inherited from QgsProcessingParameterDefinition
QStringList mAdditionalExpressionVariables
 Additional expression context variables exposed for use by this parameter. More...
 
QgsProcessingAlgorithmmAlgorithm = nullptr
 Pointer to algorithm which owns this parameter. More...
 
QVariant mDefault
 Default value for parameter. More...
 
QString mDescription
 Parameter description. More...
 
QString mDynamicLayerParameterName
 Linked vector layer parameter name for dynamic properties. More...
 
Flags mFlags
 Parameter flags. More...
 
QString mHelp
 Parameter help. More...
 
bool mIsDynamic = false
 True for dynamic parameters, which can have data-defined (QgsProperty) based values. More...
 
QVariantMap mMetadata
 Freeform metadata for parameter. Mostly used by widget wrappers to customize their appearance and behavior. More...
 
QString mName
 Parameter name. More...
 
QgsPropertyDefinition mPropertyDefinition
 Data defined property definition. More...
 

Detailed Description

A generic file based destination parameter, for specifying the destination path for a file (non-map layer) created by the algorithm.

In some circumstances it is desirable to avoid the usual file overwriting confirmation prompt when users select an existing destination file for this parameter type (e.g., for algorithms which append to an existing destination file instead of overwriting them.). This can be done by setting the widget wrapper metadata "dontconfirmoverwrite" option:

param = QgsProcessingParameterFileDestination( 'OUTPUT', 'Destination file')
# don't show the file overwrite warning when users select a destination file:
param.setMetadata( {'widget_wrapper':
{ 'dontconfirmoverwrite': True }
})
Since
QGIS 3.0

Definition at line 3126 of file qgsprocessingparameters.h.

Constructor & Destructor Documentation

◆ QgsProcessingParameterFileDestination()

QgsProcessingParameterFileDestination::QgsProcessingParameterFileDestination ( const QString &  name,
const QString &  description = QString(),
const QString &  fileFilter = QString(),
const QVariant &  defaultValue = QVariant(),
bool  optional = false,
bool  createByDefault = true 
)

Constructor for QgsProcessingParameterFileDestination.

If createByDefault is false and the parameter is optional, then this destination output will not be created by default.

Definition at line 5750 of file qgsprocessingparameters.cpp.

Member Function Documentation

◆ asPythonString()

QString QgsProcessingParameterFileDestination::asPythonString ( QgsProcessing::PythonOutputType  outputType = QgsProcessing::PythonQgsProcessingAlgorithmSubclass) const
overridevirtual

Returns the parameter definition as a Python command which can be used within a Python Processing script.

The outputType argument specifies the desired output format for the Python string, i.e. the intended end use of the generated Python code.

Since
QGIS 3.6

Reimplemented from QgsProcessingDestinationParameter.

Definition at line 5848 of file qgsprocessingparameters.cpp.

◆ checkValueIsAcceptable()

bool QgsProcessingParameterFileDestination::checkValueIsAcceptable ( const QVariant &  input,
QgsProcessingContext context = nullptr 
) const
overridevirtual

Checks whether the specified input value is acceptable for the parameter.

Returns true if the value can be accepted. The optional context parameter can be specified to allow a more stringent check to be performed, capable of checking for the presence of required layers and other factors within the context.

Reimplemented from QgsProcessingParameterDefinition.

Definition at line 5762 of file qgsprocessingparameters.cpp.

◆ clone()

QgsProcessingParameterDefinition * QgsProcessingParameterFileDestination::clone ( ) const
overridevirtual

Creates a clone of the parameter definition.

Implements QgsProcessingParameterDefinition.

Definition at line 5757 of file qgsprocessingparameters.cpp.

◆ createFileFilter()

QString QgsProcessingParameterFileDestination::createFileFilter ( ) const
overridevirtual

This method needs to be reimplemented in all classes which implement this interface and return a file filter.

Reimplemented from QgsProcessingDestinationParameter.

Definition at line 5870 of file qgsprocessingparameters.cpp.

◆ defaultFileExtension()

QString QgsProcessingParameterFileDestination::defaultFileExtension ( ) const
overridevirtual

Returns the default file extension for destination file paths associated with this parameter.

Implements QgsProcessingDestinationParameter.

Definition at line 5834 of file qgsprocessingparameters.cpp.

◆ fileFilter()

QString QgsProcessingParameterFileDestination::fileFilter ( ) const

Returns the file filter string for file destinations compatible with this parameter.

See also
setFileFilter()

Definition at line 5875 of file qgsprocessingparameters.cpp.

◆ fromScriptCode()

QgsProcessingParameterFileDestination * QgsProcessingParameterFileDestination::fromScriptCode ( const QString &  name,
const QString &  description,
bool  isOptional,
const QString &  definition 
)
static

Creates a new parameter using the definition from a script code.

Definition at line 5900 of file qgsprocessingparameters.cpp.

◆ fromVariantMap()

bool QgsProcessingParameterFileDestination::fromVariantMap ( const QVariantMap &  map)
overridevirtual

Restores this parameter to a QVariantMap.

Subclasses should ensure that they call the base class method.

See also
toVariantMap()

Reimplemented from QgsProcessingDestinationParameter.

Definition at line 5892 of file qgsprocessingparameters.cpp.

◆ setFileFilter()

void QgsProcessingParameterFileDestination::setFileFilter ( const QString &  filter)

Sets the file filter string for file destinations compatible with this parameter.

See also
fileFilter()

Definition at line 5880 of file qgsprocessingparameters.cpp.

◆ toOutputDefinition()

QgsProcessingOutputDefinition * QgsProcessingParameterFileDestination::toOutputDefinition ( ) const
overridevirtual

Returns a new QgsProcessingOutputDefinition corresponding to the definition of the destination parameter.

Implements QgsProcessingDestinationParameter.

Definition at line 5822 of file qgsprocessingparameters.cpp.

◆ toVariantMap()

QVariantMap QgsProcessingParameterFileDestination::toVariantMap ( ) const
overridevirtual

Saves this parameter to a QVariantMap.

Subclasses should ensure that they call the base class method and then extend the result with additional properties.

See also
fromVariantMap()

Reimplemented from QgsProcessingDestinationParameter.

Definition at line 5885 of file qgsprocessingparameters.cpp.

◆ type()

QString QgsProcessingParameterFileDestination::type ( ) const
inlineoverridevirtual

Unique parameter type name.

Implements QgsProcessingParameterDefinition.

Definition at line 3147 of file qgsprocessingparameters.h.

◆ typeName()

static QString QgsProcessingParameterFileDestination::typeName ( )
inlinestatic

Returns the type name for the parameter class.

Definition at line 3145 of file qgsprocessingparameters.h.

◆ valueAsPythonString()

QString QgsProcessingParameterFileDestination::valueAsPythonString ( const QVariant &  value,
QgsProcessingContext context 
) const
overridevirtual

Returns a string version of the parameter input value, which is suitable for use as an input parameter value when running an algorithm directly from a Python command.

Reimplemented from QgsProcessingParameterDefinition.

Definition at line 5798 of file qgsprocessingparameters.cpp.


The documentation for this class was generated from the following files:
QgsProcessingParameterFileDestination
A generic file based destination parameter, for specifying the destination path for a file (non-map l...
Definition: qgsprocessingparameters.h:3127