A Proxy Model which presents a subset of its source model to observers. More...

#include <kselectionproxymodel.h>

Inheritance diagram for KSelectionProxyModel:

Public Types
enum	FilterBehavior { SubTrees, SubTreeRoots, SubTreesWithoutRoots, ExactSelection, ChildrenOfExactSelection }
Signals
void	rootIndexAboutToBeRemoved (const QModelIndex &removeRootIndex)
void	rootIndexAdded (const QModelIndex &newIndex)
void	rootSelectionAboutToBeRemoved (const QItemSelection &selection)
void	rootSelectionAdded (const QItemSelection &selection)
Public Member Functions
	KSelectionProxyModel (QItemSelectionModel selectionModel, QObject parent=0)
virtual	~KSelectionProxyModel ()
virtual int	columnCount (const QModelIndex &=QModelIndex()) const
QVariant	data (const QModelIndex &index, int role=Qt::DisplayRole) const
virtual bool	dropMimeData (const QMimeData *data, Qt::DropAction action, int row, int column, const QModelIndex &parent)
FilterBehavior	filterBehavior () const
virtual Qt::ItemFlags	flags (const QModelIndex &index) const
virtual bool	hasChildren (const QModelIndex &parent=QModelIndex()) const
virtual QVariant	headerData (int section, Qt::Orientation orientation, int role=Qt::DisplayRole) const
virtual QModelIndex	index (int, int, const QModelIndex &=QModelIndex()) const
QModelIndex	mapFromSource (const QModelIndex &sourceIndex) const
QItemSelection	mapSelectionFromSource (const QItemSelection &selection) const
QItemSelection	mapSelectionToSource (const QItemSelection &selection) const
QModelIndex	mapToSource (const QModelIndex &proxyIndex) const
virtual QModelIndexList	match (const QModelIndex &start, int role, const QVariant &value, int hits=1, Qt::MatchFlags flags=Qt::MatchFlags(Qt::MatchStartsWith\|Qt::MatchWrap)) const
virtual QMimeData *	mimeData (const QModelIndexList &indexes) const
virtual QStringList	mimeTypes () const
virtual QModelIndex	parent (const QModelIndex &) const
virtual int	rowCount (const QModelIndex &parent=QModelIndex()) const
QItemSelectionModel *	selectionModel () const
void	setFilterBehavior (FilterBehavior behavior)
virtual void	setSourceModel (QAbstractItemModel *sourceModel)
virtual Qt::DropActions	supportedDropActions () const
Protected Member Functions
QList< QPersistentModelIndex >	sourceRootIndexes () const

Detailed Description

A Proxy Model which presents a subset of its source model to observers.

The KSelectionProxyModel is most useful as a convenience for displaying the selection in one view in another view. The selectionModel of the initial view is used to create a proxied model which is filtered based on the configuration of this class.

For example, when a user clicks a mail folder in one view in an email application, the contained emails should be displayed in another view.

This takes away the need for the developer to handle the selection between the views, including all the mapToSource, mapFromSource and setRootIndex calls.

  MyModel *sourceModel = new MyModel(this);
  QTreeView *leftView = new QTreeView(this);
  leftView->setModel(sourceModel);

  KSelectionProxyModel *selectionProxy = new KSelectionProxyModel(leftView->selectionModel(), this);
  selectionProxy->setSourceModel(sourceModel);

  QTreeView *rightView = new QTreeView(this);
  rightView->setModel(selectionProxy);

A Selection in one view creating a model for use with another view.

The KSelectionProxyModel can handle complex selections.

Non-contiguous selection creating a new simple model in a second view.

The contents of the secondary view depends on the selection in the primary view, and the configuration of the proxy model. See KSelectionProxyModel::setFilterBehavior for the different possible configurations.

For example, if the filterBehavior is SubTrees, selecting another item in an already selected subtree has no effect.

selectionproxymodelmultipleselection-withdescendant.png

Selecting an item and its descendant.

See the test application in KDE/kdelibs/kdeui/tests/proxymodeltestapp to try out the valid configurations.

KSelectionProxyModel test application

Obviously, the KSelectionProxyModel may be used in a view, or further processed with other proxy models. See KAddressBook and AkonadiConsole in kdepim for examples which use a further KDescendantsProxyModel and QSortFilterProxyModel on top of a KSelectionProxyModel.

Additionally, this class can be used to programmatically choose some items from the source model to display in the view. For example, this is how the Favourite Folder View in KMail works, and is also used in unit testing.

Since:: 4.4

Author:: Stephen Kelly <steveire@gmail.com>

Definition at line 86 of file kselectionproxymodel.h.

Member Enumeration Documentation

enum KSelectionProxyModel::FilterBehavior

Enumerator:

SubTrees
SubTreeRoots
SubTreesWithoutRoots
ExactSelection
ChildrenOfExactSelection

Definition at line 110 of file kselectionproxymodel.h.

Constructor & Destructor Documentation

KSelectionProxyModel::KSelectionProxyModel	(	QItemSelectionModel *	selectionModel,
		QObject *	parent = `0`
	)		`[explicit]`

ctor.

selectionModel The selection model used to filter what is presented by the proxy.

Definition at line 1937 of file kselectionproxymodel.cpp.

KSelectionProxyModel::~KSelectionProxyModel ( ) [virtual]

dtor

Definition at line 1942 of file kselectionproxymodel.cpp.

Member Function Documentation

int KSelectionProxyModel::columnCount ( const QModelIndex & index = QModelIndex() ) const [virtual]

Definition at line 2261 of file kselectionproxymodel.cpp.

QVariant KSelectionProxyModel::data	(	const QModelIndex &	index,
		int	role = `Qt::DisplayRole`
	)		const

Definition at line 2197 of file kselectionproxymodel.cpp.

bool KSelectionProxyModel::dropMimeData	(	const QMimeData *	data,
		Qt::DropAction	action,
		int	row,
		int	column,
		const QModelIndex &	parent
	)		`[virtual]`

Definition at line 2284 of file kselectionproxymodel.cpp.

KSelectionProxyModel::FilterBehavior KSelectionProxyModel::filterBehavior ( ) const

Definition at line 1996 of file kselectionproxymodel.cpp.

Qt::ItemFlags KSelectionProxyModel::flags ( const QModelIndex & index ) const [virtual]

Definition at line 2185 of file kselectionproxymodel.cpp.

bool KSelectionProxyModel::hasChildren ( const QModelIndex & parent = QModelIndex() ) const [virtual]

Definition at line 2241 of file kselectionproxymodel.cpp.

QVariant KSelectionProxyModel::headerData	(	int	section,
		Qt::Orientation	orientation,
		int	role = `Qt::DisplayRole`
	)		const `[virtual]`

Definition at line 2210 of file kselectionproxymodel.cpp.

QModelIndex KSelectionProxyModel::index	(	int	row,
		int	column,
		const QModelIndex &	parent = `QModelIndex()`
	)		const `[virtual]`

Definition at line 2156 of file kselectionproxymodel.cpp.

QModelIndex KSelectionProxyModel::mapFromSource ( const QModelIndex & sourceIndex ) const

Definition at line 2109 of file kselectionproxymodel.cpp.

QItemSelection KSelectionProxyModel::mapSelectionFromSource ( const QItemSelection & selection ) const

Definition at line 2332 of file kselectionproxymodel.cpp.

QItemSelection KSelectionProxyModel::mapSelectionToSource ( const QItemSelection & selection ) const

Definition at line 2367 of file kselectionproxymodel.cpp.

QModelIndex KSelectionProxyModel::mapToSource ( const QModelIndex & proxyIndex ) const

Definition at line 2089 of file kselectionproxymodel.cpp.

QModelIndexList KSelectionProxyModel::match	(	const QModelIndex &	start,
		int	role,
		const QVariant &	value,
		int	hits = `1`,
		Qt::MatchFlags	flags = `Qt::MatchFlags(Qt::MatchStartsWith \| Qt::MatchWrap)`
	)		const `[virtual]`

Definition at line 2317 of file kselectionproxymodel.cpp.

QMimeData * KSelectionProxyModel::mimeData ( const QModelIndexList & indexes ) const [virtual]

Definition at line 2217 of file kselectionproxymodel.cpp.

QStringList KSelectionProxyModel::mimeTypes ( ) const [virtual]

Definition at line 2227 of file kselectionproxymodel.cpp.

QModelIndex KSelectionProxyModel::parent ( const QModelIndex & index ) const [virtual]

Definition at line 2173 of file kselectionproxymodel.cpp.

void KSelectionProxyModel::rootIndexAboutToBeRemoved ( const QModelIndex & removeRootIndex ) [signal]

Emitted before removeRootIndex, an index in the sourceModel is removed from the root selected indexes. This may be unrelated to rows removed from the model, depending on configuration.

void KSelectionProxyModel::rootIndexAdded ( const QModelIndex & newIndex ) [signal]

Emitted when newIndex, an index in the sourceModel is added to the root selected indexes. This may be unrelated to rows inserted to the model, depending on configuration.

void KSelectionProxyModel::rootSelectionAboutToBeRemoved ( const QItemSelection & selection ) [signal]

Emitted before selection, a selection in the sourceModel, is removed from the root selection.

void KSelectionProxyModel::rootSelectionAdded ( const QItemSelection & selection ) [signal]

Emitted after selection, a selection in the sourceModel, is added to the root selection.

int KSelectionProxyModel::rowCount ( const QModelIndex & parent = QModelIndex() ) const [virtual]

Definition at line 2127 of file kselectionproxymodel.cpp.

QItemSelectionModel * KSelectionProxyModel::selectionModel ( ) const

Definition at line 2278 of file kselectionproxymodel.cpp.

void KSelectionProxyModel::setFilterBehavior ( FilterBehavior behavior )

Set the filter behaviors of this model.

The filter behaviors of the model govern the content of the model based on the selection of the contained QItemSelectionModel.

See kdeui/proxymodeltestapp to try out the different proxy model behaviors.

The most useful behaviors are SubTrees, ExactSelection and ChildrenOfExactSelection.

The default behavior is SubTrees. This means that this proxy model will contain the roots of the items in the source model. Any descendants which are also selected have no additional effect. For example if the source model is like:

And A, B, C and D are selected, the proxy will contain:

That is, selecting 'D' or 'C' if 'B' is also selected has no effect. If 'B' is de-selected, then 'C' amd 'D' become top-level items:

This is the behavior used by KJots when rendering books.

If the behavior is set to SubTreeRoots, then the children of selected indexes are not part of the model. If 'A', 'B' and 'D' are selected,

      (root)
        - A
        - B

Note that although 'D' is selected, it is not part of the proxy model, because its parent 'B' is already selected.

SubTreesWithoutRoots has the effect of not making the selected items part of the model, but making their children part of the model instead. If 'A', 'B' and 'I' are selected:

Note that 'A' has no children, so selecting it has no outward effect on the model.

ChildrenOfExactSelection causes the proxy model to contain the children of the selected indexes,but further descendants are omitted. Additionally, if descendants of an already selected index are selected, their children are part of the proxy model. For example, if 'A', 'B', 'D' and 'I' are selected:

      (root)
        - C
        - D
        - E
        - G
        - J
        - K
        - L

This would be useful for example if showing containers (for example maildirs) in one view and their items in another. Sub-maildirs would still appear in the proxy, but could be filtered out using a QSortfilterProxyModel.

The ExactSelection behavior causes the selected items to be part of the proxy model, even if their ancestors are already selected, but children of selected items are not included.

Again, if 'A', 'B', 'D' and 'I' are selected:

      (root)
        - A
        - B
        - D
        - I

This is the behavior used by the Favourite Folder View in KMail.

Definition at line 1947 of file kselectionproxymodel.cpp.

void KSelectionProxyModel::setSourceModel ( QAbstractItemModel * sourceModel ) [virtual]

reimp.

Definition at line 2002 of file kselectionproxymodel.cpp.

QList< QPersistentModelIndex > KSelectionProxyModel::sourceRootIndexes ( ) const [protected]

Definition at line 2311 of file kselectionproxymodel.cpp.

Qt::DropActions KSelectionProxyModel::supportedDropActions ( ) const [virtual]

Definition at line 2234 of file kselectionproxymodel.cpp.

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

KDEUI

KSelectionProxyModel Class Reference

Public Types

Signals

Public Member Functions

Protected Member Functions

Detailed Description

Member Enumeration Documentation

Constructor & Destructor Documentation

Member Function Documentation

KDEUI

kdelibs