Wt  4.11.0
Loading...
Searching...
No Matches
Classes | Public Member Functions | Protected Types | Protected Member Functions | List of all members
Wt::WAbstractProxyModel Class Referenceabstract

An abstract proxy model for Wt's item models. More...

#include <Wt/WAbstractProxyModel.h>

Inheritance diagram for Wt::WAbstractProxyModel:
[legend]

Classes

struct  BaseItem
 A base class for an item modeling a source index parent. More...
 

Public Member Functions

 WAbstractProxyModel ()
 Constructor.
 
virtual WModelIndex mapFromSource (const WModelIndex &sourceIndex) const =0
 Maps a source model index to the proxy model.
 
virtual WModelIndex mapToSource (const WModelIndex &proxyIndex) const =0
 Maps a proxy model index to the source model.
 
virtual void setSourceModel (const std::shared_ptr< WAbstractItemModel > &sourceModel)
 Sets the source model.
 
std::shared_ptr< WAbstractItemModelsourceModel () const
 Returns the source model.
 
virtual cpp17::any data (const WModelIndex &index, ItemDataRole role=ItemDataRole::Display) const override
 Returns the data at a specific model index.
 
virtual cpp17::any headerData (int section, Orientation orientation=Orientation::Horizontal, ItemDataRole role=ItemDataRole::Display) const override
 Returns the row or column header data.
 
virtual bool setData (const WModelIndex &index, const cpp17::any &value, ItemDataRole role=ItemDataRole::Edit) override
 Sets the data at the given model index.
 
virtual bool setItemData (const WModelIndex &index, const DataMap &values) override
 Sets the data at the given model index.
 
virtual WFlags< ItemFlagflags (const WModelIndex &index) const override
 Returns the flags for an item.
 
virtual WFlags< HeaderFlagheaderFlags (int section, Orientation orientation=Orientation::Horizontal) const override
 Returns the flags for a header.
 
virtual bool insertColumns (int column, int count, const WModelIndex &parent=WModelIndex()) override
 Inserts one or more columns.
 
virtual bool removeColumns (int column, int count, const WModelIndex &parent=WModelIndex()) override
 Removes columns.
 
virtual std::string mimeType () const override
 Returns a mime-type for dragging a set of indexes.
 
virtual std::vector< std::string > acceptDropMimeTypes () const override
 Returns a list of mime-types that could be accepted for a drop event.
 
virtual void dropEvent (const WDropEvent &e, DropAction action, int row, int column, const WModelIndex &parent) override
 Handles a drop event.
 
virtual voidtoRawIndex (const WModelIndex &index) const override
 Converts a model index to a raw pointer that remains valid while the model's layout is changed.
 
virtual WModelIndex fromRawIndex (void *rawIndex) const override
 Converts a raw pointer to a model index.
 
virtual bool setData (const WModelIndex &index, const cpp17::any &value, ItemDataRole role=ItemDataRole::Edit)
 Sets data at the given model index.
 
bool setData (int row, int column, const cpp17::any &value, ItemDataRole role=ItemDataRole::Edit, const WModelIndex &parent=WModelIndex())
 Sets data at the given row and column.
 
virtual cpp17::any data (const WModelIndex &index, ItemDataRole role=ItemDataRole::Display) const=0
 Returns data at a specified model index for the given role.
 
cpp17::any data (int row, int column, ItemDataRole role=ItemDataRole::Display, const WModelIndex &parent=WModelIndex()) const
 Returns the data item at the given column and row.
 
virtual bool setHeaderData (int section, Orientation orientation, const cpp17::any &value, ItemDataRole role=ItemDataRole::Edit)
 Sets header data for a column or row.
 
bool setHeaderData (int section, const cpp17::any &value)
 Sets column header data.
 
- Public Member Functions inherited from Wt::WAbstractItemModel
 WAbstractItemModel ()
 Creates a new data model.
 
virtual int columnCount (const WModelIndex &parent=WModelIndex()) const =0
 Returns the number of columns.
 
virtual int rowCount (const WModelIndex &parent=WModelIndex()) const =0
 Returns the number of rows.
 
virtual bool hasChildren (const WModelIndex &index) const
 Returns if there are children at an index.
 
virtual WModelIndex parent (const WModelIndex &index) const =0
 Returns the parent for a model index.
 
virtual DataMap itemData (const WModelIndex &index) const
 Returns all data at a specific index.
 
virtual WModelIndex index (int row, int column, const WModelIndex &parent=WModelIndex()) const =0
 Returns the child index for the given row and column.
 
virtual WModelIndexList match (const WModelIndex &start, ItemDataRole role, const cpp17::any &value, int hits=-1, WFlags< MatchFlag > flags=WFlags< MatchFlag >(MatchFlag::StartsWith|MatchFlag::Wrap)) const
 Returns an index list for data items that match.
 
cpp17::any data (int row, int column, ItemDataRole role=ItemDataRole::Display, const WModelIndex &parent=WModelIndex()) const
 Returns the data item at the given column and row.
 
virtual bool hasIndex (int row, int column, const WModelIndex &parent=WModelIndex()) const
 Returns if an index at the given position is valid (i.e. falls within the column-row bounds).
 
virtual bool insertRows (int row, int count, const WModelIndex &parent=WModelIndex())
 Inserts one or more rows.
 
virtual bool removeRows (int row, int count, const WModelIndex &parent=WModelIndex())
 Removes rows.
 
bool setHeaderData (int section, const cpp17::any &value)
 Sets column header data.
 
virtual void sort (int column, SortOrder order=SortOrder::Ascending)
 Sorts the model according to a particular column.
 
virtual void expandColumn (int column)
 Expands a column.
 
virtual void collapseColumn (int column)
 Collapses a column.
 
virtual void dropEvent (const WDropEvent &e, DropAction action, const WModelIndex &index, Wt::Side side)
 Handles a drop event.
 
bool insertColumn (int column, const WModelIndex &parent=WModelIndex())
 Inserts one column.
 
bool insertRow (int row, const WModelIndex &parent=WModelIndex())
 Inserts one row.
 
bool removeColumn (int column, const WModelIndex &parent=WModelIndex())
 Removes one column.
 
bool removeRow (int row, const WModelIndex &parent=WModelIndex())
 Removes one row.
 
bool setData (int row, int column, const cpp17::any &value, ItemDataRole role=ItemDataRole::Edit, const WModelIndex &parent=WModelIndex())
 Sets data at the given row and column.
 
virtual Signal< WModelIndex, int, int > & columnsAboutToBeInserted ()
 Signal emitted before a number of columns will be inserted.
 
virtual Signal< WModelIndex, int, int > & columnsAboutToBeRemoved ()
 Signal emitted before a number of columns will be removed.
 
virtual Signal< WModelIndex, int, int > & columnsInserted ()
 Signal emitted after a number of columns were inserted.
 
virtual Signal< WModelIndex, int, int > & columnsRemoved ()
 Signal emitted after a number of columns were removed.
 
virtual Signal< WModelIndex, int, int > & rowsAboutToBeInserted ()
 Signal emitted before a number of rows will be inserted.
 
virtual Signal< WModelIndex, int, int > & rowsAboutToBeRemoved ()
 Signal emitted before a number of rows will be removed.
 
virtual Signal< WModelIndex, int, int > & rowsInserted ()
 Signal emitted after a number of rows were inserted.
 
virtual Signal< WModelIndex, int, int > & rowsRemoved ()
 Signal emitted after a number of rows were removed.
 
virtual Signal< WModelIndex, WModelIndex > & dataChanged ()
 Signal emitted when some data was changed.
 
virtual Signal< Orientation, int, int > & headerDataChanged ()
 Signal emitted when some header data was changed.
 
virtual SignallayoutAboutToBeChanged ()
 Signal emitted when the layout is about to be changed.
 
virtual SignallayoutChanged ()
 Signal emitted when the layout is changed.
 
virtual SignalmodelReset ()
 Signal emitted when the model was reset.
 
- Public Member Functions inherited from Wt::WObject
void addChild (std::unique_ptr< WObject > child)
 Add a child WObject whose lifetime is determined by this WObject.
 
template<typename Child >
ChildaddChild (std::unique_ptr< Child > child)
 Add a child WObject, returning a raw pointer.
 
std::unique_ptr< WObjectremoveChild (WObject *child)
 Remove a child WObject, so its lifetime is no longer determined by this WObject.
 
template<typename Child >
std::unique_ptr< ChildremoveChild (Child *child)
 Remove a child WObject, so its lifetime is no longer determined by this WObject.
 
virtual const std::string id () const
 Returns the (unique) identifier for this object.
 
virtual void setObjectName (const std::string &name)
 Sets an object name.
 
virtual std::string objectName () const
 Returns the object name.
 
void resetLearnedSlots ()
 Resets learned stateless slot implementations.
 
template<class T >
void resetLearnedSlot (void(T::*method)())
 Resets a learned stateless slot implementation.
 
template<class T >
WStatelessSlot * implementStateless (void(T::*method)())
 Declares a slot to be stateless and learn client-side behaviour on first invocation.
 
template<class T >
WStatelessSlot * implementStateless (void(T::*method)(), void(T::*undoMethod)())
 Declares a slot to be stateless and learn client-side behaviour in advance.
 
void isNotStateless ()
 Marks the current function as not stateless.
 
template<class T >
WStatelessSlot * implementJavaScript (void(T::*method)(), const std::string &jsCode)
 Provides a JavaScript implementation for a method.
 
- Public Member Functions inherited from Wt::Core::observable
 observable () noexcept
 Default constructor.
 
virtual ~observable ()
 Destructor.
 
template<typename... Args, typename C >
auto bindSafe (void(C::*method)(Args...)) noexcept
 Protects a method call against object destruction.
 
template<typename... Args, typename C >
auto bindSafe (void(C::*method)(Args...) const) const noexcept
 Protects a const method call against object destruction.
 
template<typename Function >
auto bindSafe (const Function &function) noexcept
 Protects a function against object destruction.
 

Protected Types

typedef std::map< WModelIndex, BaseItem * > ItemMap
 A map for items.
 

Protected Member Functions

WModelIndex createSourceIndex (int row, int column, void *ptr) const
 Create a source model index.
 
void startShiftModelIndexes (const WModelIndex &sourceParent, int start, int count, ItemMap &items)
 Utility methods to shift items in an item map.
 
- Protected Member Functions inherited from Wt::WAbstractItemModel
void reset ()
 Resets the model and invalidate any data.
 
WModelIndex createIndex (int row, int column, void *ptr) const
 Creates a model index for the given row and column.
 
WModelIndex createIndex (int row, int column, ::uint64_t id) const
 Creates a model index for the given row and column.
 
void beginInsertColumns (const WModelIndex &parent, int first, int last)
 Method to be called before inserting columns.
 
void beginInsertRows (const WModelIndex &parent, int first, int last)
 Method to be called before inserting rows.
 
void beginRemoveColumns (const WModelIndex &parent, int first, int last)
 Method to be called before removing columns.
 
void beginRemoveRows (const WModelIndex &parent, int first, int last)
 Method to be called before removing rows.
 
void endInsertColumns ()
 Method to be called after inserting columns.
 
void endInsertRows ()
 Method to be called after inserting rows.
 
void endRemoveColumns ()
 Method to be called after removing columns.
 
void endRemoveRows ()
 Method to be called after removing rows.
 
virtual void copyData (const WModelIndex &sIndex, const WModelIndex &dIndex)
 Copy data to an index in this model.
 
- Protected Member Functions inherited from Wt::WObject
virtual WStatelessSlot * getStateless (Method method)
 On-demand stateless slot implementation.
 

Additional Inherited Members

- Public Types inherited from Wt::WAbstractItemModel
typedef std::map< ItemDataRole, cpp17::any > DataMap
 Data map.
 
- Public Types inherited from Wt::WObject
typedef void(WObject::* Method) ()
 Typedef for a WObject method without arguments.
 

Detailed Description

An abstract proxy model for Wt's item models.

A proxy model does not store data, but presents data from a source model in another way. It may provide filtering, sorting, or other computed changes to the source model. A proxy model may be a fully functional model, that also allows modification of the underlying model.

This abstract proxy model may be used as a starting point for implementing a custom proxy model, when WSortFilterProxyModel is not adequate. It implements data access and manipulation using the a virtual mapping method (mapToSource()) to access and manipulate the underlying sourceModel().

Member Typedef Documentation

◆ ItemMap

A map for items.

See also
BaseItem

Member Function Documentation

◆ acceptDropMimeTypes()

virtual std::vector< std::string > Wt::WAbstractProxyModel::acceptDropMimeTypes ( ) const
overridevirtual

Returns a list of mime-types that could be accepted for a drop event.

The default proxy implementation calls sourceModel()->acceptDropMimeTypes()

Reimplemented from Wt::WAbstractItemModel.

◆ createSourceIndex()

WModelIndex Wt::WAbstractProxyModel::createSourceIndex ( int  row,
int  column,
void ptr 
) const
protected

Create a source model index.

This is a utility function that allows you to create indexes in the source model. In this way, you can reuse the internal pointers of the source model in proxy model indexes, and convert a proxy model index back to the source model index using this method.

◆ data() [1/3]

virtual cpp17::any Wt::WAbstractProxyModel::data ( const WModelIndex index,
ItemDataRole  role = ItemDataRole::Display 
) const
overridevirtual

Returns the data at a specific model index.

The default proxy implementation translates the index to the source model, and calls sourceModel()->data() with this index.

Implements Wt::WAbstractItemModel.

Reimplemented in Wt::WBatchEditProxyModel, and Wt::WBatchEditProxyModel.

◆ data() [2/3]

virtual cpp17::any Wt::WAbstractItemModel::data ( const WModelIndex index,
ItemDataRole  role = ItemDataRole::Display 
) const
virtual

Returns data at a specified model index for the given role.

You should check the role to decide what data to return. Usually a View class will ask for data for several roles which affect not only the contents (Wt::ItemDataRole::Display) but also icons (Wt::ItemDataRole::Decoration), URLs (Wt::ItemDataRole::Link), and other visual aspects. If your item does not specify data for a particular role, it should simply return a Wt::cpp17::any().

See also
flags(), headerData(), setData()

Implements Wt::WAbstractItemModel.

Reimplemented in Wt::WBatchEditProxyModel, and Wt::WBatchEditProxyModel.

◆ data() [3/3]

cpp17::any Wt::WAbstractItemModel::data ( int  row,
int  column,
ItemDataRole  role = ItemDataRole::Display,
const WModelIndex parent = WModelIndex() 
) const

Returns the data item at the given column and row.

This is a convenience method, and is equivalent to:

index(row, column, parent).data(role)
A signal that conveys user-interface events.
Definition WSignal.h:558
virtual WModelIndex index(int row, int column, const WModelIndex &parent=WModelIndex()) const =0
Returns the child index for the given row and column.
virtual WModelIndex parent(const WModelIndex &index) const =0
Returns the parent for a model index.
See also
index(), data()

◆ dropEvent()

virtual void Wt::WAbstractProxyModel::dropEvent ( const WDropEvent e,
DropAction  action,
int  row,
int  column,
const WModelIndex parent 
)
overridevirtual

Handles a drop event.

The default proxy implementation maps the given row and parent to the row and parent in the source model, and forwards the dropEvent call to the source model.

Reimplemented from Wt::WAbstractItemModel.

Reimplemented in Wt::WReadOnlyProxyModel.

◆ flags()

virtual WFlags< ItemFlag > Wt::WAbstractProxyModel::flags ( const WModelIndex index) const
overridevirtual

Returns the flags for an item.

The default proxy implementation calls sourceModel()->flags(mapToSource(index))

Reimplemented from Wt::WAbstractItemModel.

Reimplemented in Wt::WBatchEditProxyModel.

◆ fromRawIndex()

virtual WModelIndex Wt::WAbstractProxyModel::fromRawIndex ( void rawIndex) const
overridevirtual

Converts a raw pointer to a model index.

The default proxy implementation calls mapFromSource(sourceModel()->fromRawIndex(rawIndex))

Reimplemented from Wt::WAbstractItemModel.

◆ headerData()

virtual cpp17::any Wt::WAbstractProxyModel::headerData ( int  section,
Orientation  orientation = Orientation::Horizontal,
ItemDataRole  role = ItemDataRole::Display 
) const
overridevirtual

Returns the row or column header data.

The default proxy implementation constructs a dummy WModelIndex with the row set to 0 and column set to section if the orientation is Wt::Orientation::Horizontal, or with the row set to section and the column set to 0 if the orientation is Wt::Orientation::Vertical.

The resulting section that is forwarded to sourceModel()->headerData() depends on how the WModelIndex is transformed with mapToSource().

Reimplemented from Wt::WAbstractItemModel.

Reimplemented in Wt::WAggregateProxyModel, Wt::WBatchEditProxyModel, and Wt::WSortFilterProxyModel.

◆ headerFlags()

virtual WFlags< HeaderFlag > Wt::WAbstractProxyModel::headerFlags ( int  section,
Orientation  orientation = Orientation::Horizontal 
) const
overridevirtual

Returns the flags for a header.

The default proxy implementation constructs a dummy WModelIndex with the row set to 0 and column set to section if the orientation is Wt::Orientation::Horizontal, or with the row set to section and the column set to 0 if the orientation is Wt::Orientation::Vertical.

The resulting section that is forwarded to sourceModel()->headerFlags() depends on how the WModelIndex is transformed with mapToSource().

Reimplemented from Wt::WAbstractItemModel.

Reimplemented in Wt::WAggregateProxyModel, and Wt::WSortFilterProxyModel.

◆ insertColumns()

virtual bool Wt::WAbstractProxyModel::insertColumns ( int  column,
int  count,
const WModelIndex parent = WModelIndex() 
)
overridevirtual

Inserts one or more columns.

The default proxy implementation calls sourceModel()->insertColumns(column, count, parent)

Reimplemented from Wt::WAbstractItemModel.

Reimplemented in Wt::WReadOnlyProxyModel, Wt::WBatchEditProxyModel, and Wt::WIdentityProxyModel.

◆ mapFromSource()

virtual WModelIndex Wt::WAbstractProxyModel::mapFromSource ( const WModelIndex sourceIndex) const
pure virtual

Maps a source model index to the proxy model.

This method returns a model index in the proxy model that corresponds to the model index sourceIndex in the source model. This method must only be implemented for source model indexes that are mapped and thus are the result of mapToSource().

See also
mapToSource()

Implemented in Wt::WAggregateProxyModel, Wt::WBatchEditProxyModel, Wt::WIdentityProxyModel, Wt::WReadOnlyProxyModel, and Wt::WSortFilterProxyModel.

◆ mapToSource()

virtual WModelIndex Wt::WAbstractProxyModel::mapToSource ( const WModelIndex proxyIndex) const
pure virtual

Maps a proxy model index to the source model.

This method returns a model index in the source model that corresponds to the proxy model index proxyIndex.

See also
mapFromSource()

Implemented in Wt::WAggregateProxyModel, Wt::WBatchEditProxyModel, Wt::WIdentityProxyModel, Wt::WReadOnlyProxyModel, and Wt::WSortFilterProxyModel.

◆ mimeType()

virtual std::string Wt::WAbstractProxyModel::mimeType ( ) const
overridevirtual

Returns a mime-type for dragging a set of indexes.

The default proxy implementation calls sourceModel()->mimeType()

Reimplemented from Wt::WAbstractItemModel.

◆ removeColumns()

virtual bool Wt::WAbstractProxyModel::removeColumns ( int  column,
int  count,
const WModelIndex parent = WModelIndex() 
)
overridevirtual

Removes columns.

The default proxy implementation calls sourceModel()->removeColumns(column, count, parent)

Reimplemented from Wt::WAbstractItemModel.

Reimplemented in Wt::WReadOnlyProxyModel, Wt::WBatchEditProxyModel, and Wt::WIdentityProxyModel.

◆ setData() [1/3]

virtual bool Wt::WAbstractItemModel::setData ( const WModelIndex index,
const cpp17::any &  value,
ItemDataRole  role = ItemDataRole::Edit 
)
virtual

Sets data at the given model index.

Returns true if the operation was successful.

The default implementation returns false.

The model implementation must emit the dataChanged() signal after data was changed.

See also
data()

Reimplemented from Wt::WAbstractItemModel.

Reimplemented in Wt::WBatchEditProxyModel, Wt::WReadOnlyProxyModel, Wt::WBatchEditProxyModel, Wt::WReadOnlyProxyModel, and Wt::WReadOnlyProxyModel.

◆ setData() [2/3]

virtual bool Wt::WAbstractProxyModel::setData ( const WModelIndex index,
const cpp17::any &  value,
ItemDataRole  role = ItemDataRole::Edit 
)
overridevirtual

Sets the data at the given model index.

The default proxy implementation calls sourceModel()->setData(mapToSource(index), value, role)

Reimplemented from Wt::WAbstractItemModel.

Reimplemented in Wt::WBatchEditProxyModel, Wt::WReadOnlyProxyModel, Wt::WBatchEditProxyModel, Wt::WReadOnlyProxyModel, and Wt::WReadOnlyProxyModel.

◆ setData() [3/3]

bool Wt::WAbstractItemModel::setData ( int  row,
int  column,
const cpp17::any &  value,
ItemDataRole  role = ItemDataRole::Edit,
const WModelIndex parent = WModelIndex() 
)

Sets data at the given row and column.

This is a convience method, and is equivalent to:

setData(index(row, column, parent), value, role);
virtual bool setData(const WModelIndex &index, const cpp17::any &value, ItemDataRole role=ItemDataRole::Edit) override
Sets the data at the given model index.

Returns true if the operation was successful.

See also
setData(), index()

◆ setHeaderData() [1/2]

bool Wt::WAbstractItemModel::setHeaderData ( int  section,
const cpp17::any &  value 
)

Sets column header data.

Returns true if the operation was successful.

See also
setHeaderData(int, Orientation, const cpp17::any&, int)

◆ setHeaderData() [2/2]

virtual bool Wt::WAbstractItemModel::setHeaderData ( int  section,
Orientation  orientation,
const cpp17::any &  value,
ItemDataRole  role = ItemDataRole::Edit 
)
virtual

Sets header data for a column or row.

Returns true if the operation was successful.

See also
headerData()

Reimplemented from Wt::WAbstractItemModel.

Reimplemented in Wt::WBatchEditProxyModel, Wt::WIdentityProxyModel, Wt::WReadOnlyProxyModel, Wt::WAggregateProxyModel, Wt::WIdentityProxyModel, Wt::WReadOnlyProxyModel, and Wt::WSortFilterProxyModel.

◆ setItemData()

virtual bool Wt::WAbstractProxyModel::setItemData ( const WModelIndex index,
const DataMap values 
)
overridevirtual

Sets the data at the given model index.

The default proxy implementation calls sourceModel()->setData(mapToSource(index), values)

Reimplemented from Wt::WAbstractItemModel.

Reimplemented in Wt::WReadOnlyProxyModel.

◆ setSourceModel()

virtual void Wt::WAbstractProxyModel::setSourceModel ( const std::shared_ptr< WAbstractItemModel > &  sourceModel)
virtual

Sets the source model.

The source model provides the actual data for the proxy model.

Ownership of the source model is not transferred.

Note that the source model's signals are not forwarded to the proxy model by default, but some specializations, like WBatchEditProxyModel and WSortFilterProxyModel do. If you want to reimplement data() with no changes to row or column indices, consider the use of WIdentityProxyModel.

Reimplemented in Wt::WAggregateProxyModel, Wt::WBatchEditProxyModel, Wt::WIdentityProxyModel, and Wt::WSortFilterProxyModel.

◆ sourceModel()

std::shared_ptr< WAbstractItemModel > Wt::WAbstractProxyModel::sourceModel ( ) const

Returns the source model.

See also
setSourceModel()

◆ startShiftModelIndexes()

void Wt::WAbstractProxyModel::startShiftModelIndexes ( const WModelIndex sourceParent,
int  start,
int  count,
ItemMap items 
)
protected

Utility methods to shift items in an item map.

You can use this method to adjust an item map after the source model has inserted or removed rows. When removing rows (count < 0), items may possibly be removed and deleted.

◆ toRawIndex()

virtual void * Wt::WAbstractProxyModel::toRawIndex ( const WModelIndex index) const
overridevirtual

Converts a model index to a raw pointer that remains valid while the model's layout is changed.

The default proxy implementation calls sourceModel()->toRawIndex(mapToSource(index))

Reimplemented from Wt::WAbstractItemModel.