Nepomuk::Utils::FacetModel Class Reference

#include <Nepomuk/Utils/FacetModel>

Inheritance diagram for Nepomuk::Utils::FacetModel:

Public Types
enum	CustomRoles { FacetRole = 235265643 }

Public Slots
void	addFacet (Nepomuk::Utils::Facet *facet)
void	clear ()
void	clearSelection ()
Nepomuk::Query::Query	extractFacetsFromQuery (const Nepomuk::Query::Query &query)
void	setClientQuery (const Nepomuk::Query::Query &query)
void	setFacets (const QList< Nepomuk::Utils::Facet * > &facets)

Signals
void	queryTermChanged (const Nepomuk::Query::Term &term)

Public Member Functions
	FacetModel (QObject *parent=0)
	~FacetModel ()
int	columnCount (const QModelIndex &parent=QModelIndex()) const
QVariant	data (const QModelIndex &index, int role=Qt::DisplayRole) const
QList< Facet * >	facets () const
Qt::ItemFlags	flags (const QModelIndex &index) const
bool	hasChildren (const QModelIndex &parent) const
QModelIndex	index (int row, int column, const QModelIndex &parent=QModelIndex()) const
QModelIndex	parent (const QModelIndex &index) const
Query::Term	queryTerm () const
int	rowCount (const QModelIndex &parent=QModelIndex()) const
bool	setData (const QModelIndex &index, const QVariant &value, int role)

Detailed Description

A FacetModel contains a list of facets that are provided in a tree structure.

The FacetModel manages a list of Facet instances that are layed out in a tree structure in which the leafs are checkable. This allows to easily configure the facets by clicking the tree.

Facets are added via setFacets() and addFacet().

The FacetModel can be used to create and augment queries using the queryTerm() method and connecting to the queryTermChanged() signal. In addition FacetModel provides the extractFacetsFromTerm() method which converts a query into facet selections. This is very convinient if the query comes from another source like a query bookmark or another application.

An improved user experience can be created by setting the final query used to list the results via setClientQuery(). This allows the FacetModel to filter the available choices, hiding those that do not make sense with the current result set or even showing facets that did not make sense before (compare the ProxyFacet example in Facet Examples).

Typically one would use FacetWidget instead of creating ones own FacetModel.

Author

Sebastian Trueg trueg.nosp@m.@kde.nosp@m..org

Since

4.6

Definition at line 67 of file facetmodel.h.

Member Enumeration Documentation

enum Nepomuk::Utils::FacetModel::CustomRoles

Special roles FacetModel provides through data() in addition to the standard Qt roles.

See also

Qt::ItemDataRole

Enumerator
FacetRole	Provides a pointer to the Facet instance itself. Used internally.

Definition at line 88 of file facetmodel.h.

Constructor & Destructor Documentation

Nepomuk::Utils::FacetModel::FacetModel

(

QObject *

parent = 0

)

Creates an empty facet model.

Nepomuk::Utils::FacetModel::~FacetModel

(

)

Destructor.

Member Function Documentation

void Nepomuk::Utils::FacetModel::addFacet ( Nepomuk::Utils::Facet *  facet )

slot

Add facet to the model.

Used to populate the model with facets. Ownership of facet is transferred to the model.

void Nepomuk::Utils::FacetModel::clear ( )

slot

Remove all facets from the model.

void Nepomuk::Utils::FacetModel::clearSelection ( )

slot

Convenience method that clears the selection on all facets.

See also

Facet::clearSelection()

int Nepomuk::Utils::FacetModel::columnCount

(

const QModelIndex &

parent = QModelIndex()

)

const

Reimplemented to provide facet data to Qt's model/view framework.

QVariant Nepomuk::Utils::FacetModel::data	(	const QModelIndex &	index,
		int	role = Qt::DisplayRole
	)		const

Reimplemented to provide facet data to Qt's model/view framework.

Nepomuk::Query::Query Nepomuk::Utils::FacetModel::extractFacetsFromQuery ( const Nepomuk::Query::Query &  query )

slot

Extract as many facets from a query as possible.

This method is not able to handle all kinds of queries but works well on queries created via queryTerm().

Facets supported by this model will be extracted from query and configured accordingly in the model.

Be aware that this method is not related to setClientQuery(). It is intended to split up a query in order to represent it graphically. It will, however change the client query in order to achieve the best possible term extraction. Thus, one would typically call setClientQuery after calling this method if query does not already contain the full client query.

Typically a client would call this method and then try to handle the returned rest query in another way like converting it into a desktop user query string that can be shown in a search line edit. Another idea would be to use custom filters or a simple warning for the user that additional conditions are in place that could not be "translated" into facets.

Returns

The rest query after facets have been extracted.

QList<Facet*> Nepomuk::Utils::FacetModel::facets

(

)

const

Returns

All Facet instances added via addFacet() and setFacets().

Qt::ItemFlags Nepomuk::Utils::FacetModel::flags

(

const QModelIndex &

index

)

const

Reimplemented to provide facet data to Qt's model/view framework.

bool Nepomuk::Utils::FacetModel::hasChildren

(

const QModelIndex &

parent

)

const

Reimplemented to provide facet data to Qt's model/view framework.

QModelIndex Nepomuk::Utils::FacetModel::index	(	int	row,
		int	column,
		const QModelIndex &	parent = QModelIndex()
	)		const

Reimplemented to provide facet data to Qt's model/view framework.

QModelIndex Nepomuk::Utils::FacetModel::parent

(

const QModelIndex &

index

)

const

Reimplemented to provide facet data to Qt's model/view framework.

Query::Term Nepomuk::Utils::FacetModel::queryTerm

(

)

const

Construct a query term from the selected facets in this model.

Returns

A new query which combines the facets in this model.

void Nepomuk::Utils::FacetModel::queryTermChanged ( const Nepomuk::Query::Term &  term )

signal

Emitted whenever the facets change, i.e.

when the user changes the selection or it is changed programmatically via extractFacetsFromQuery()

int Nepomuk::Utils::FacetModel::rowCount

(

const QModelIndex &

parent = QModelIndex()

)

const

Reimplemented to provide facet data to Qt's model/view framework.

void Nepomuk::Utils::FacetModel::setClientQuery ( const Nepomuk::Query::Query &  query )

slot

Can be used to set the full query the client is using (this includes facets created through this model).

It allows the facet system to disable certain choices that would not change the result set or do not make sense otherwise.

Be aware that this method is not related to extractFacetsFromTerm(). It is merely intended to improve the overall user experienceby filtering the facet choices depending on the current query.

Typically a client would call both extractFacetsFromTerm() and setClientQuery() seperately. However, they will often be called with the same query/term.

See also

Facet::setClientQuery()

bool Nepomuk::Utils::FacetModel::setData	(	const QModelIndex &	index,
		const QVariant &	value,
		int	role
	)

Reimplemented to provide facet data to Qt's model/view framework.

void Nepomuk::Utils::FacetModel::setFacets ( const QList< Nepomuk::Utils::Facet * > &  facets )

slot

Set facets as the list of facets used in this model.

Used to populate the model with facets. Ownership of the facets is transferred to the model.

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

• facetmodel.h