KSelectionProxyModel Class Reference

#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.

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.

See also: http://doc.trolltech.com/4.5/model-view-proxy-models.html

Since

4.4

Author

Stephen Kelly steve.nosp@m.ire@.nosp@m.gmail.nosp@m..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 1988 of file kselectionproxymodel.cpp.

KSelectionProxyModel::~KSelectionProxyModel ( )

virtual

dtor

Definition at line 1993 of file kselectionproxymodel.cpp.

Member Function Documentation

int KSelectionProxyModel::columnCount ( const QModelIndex &  index = QModelIndex() ) const

virtual

Definition at line 2312 of file kselectionproxymodel.cpp.

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

Definition at line 2248 of file kselectionproxymodel.cpp.

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

virtual

Definition at line 2335 of file kselectionproxymodel.cpp.

KSelectionProxyModel::FilterBehavior KSelectionProxyModel::filterBehavior

(

)

const

Definition at line 2047 of file kselectionproxymodel.cpp.

Qt::ItemFlags KSelectionProxyModel::flags ( const QModelIndex &  index ) const

virtual

Definition at line 2236 of file kselectionproxymodel.cpp.

bool KSelectionProxyModel::hasChildren ( const QModelIndex &  parent = QModelIndex() ) const

virtual

Definition at line 2292 of file kselectionproxymodel.cpp.

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

virtual

Definition at line 2261 of file kselectionproxymodel.cpp.

QModelIndex KSelectionProxyModel::index ( int  row, int  column, const QModelIndex &  parent = QModelIndex()  ) const

virtual

Definition at line 2207 of file kselectionproxymodel.cpp.

QModelIndex KSelectionProxyModel::mapFromSource

(

const QModelIndex &

sourceIndex

)

const

Definition at line 2160 of file kselectionproxymodel.cpp.

QItemSelection KSelectionProxyModel::mapSelectionFromSource

(

const QItemSelection &

selection

)

const

Definition at line 2383 of file kselectionproxymodel.cpp.

QItemSelection KSelectionProxyModel::mapSelectionToSource

(

const QItemSelection &

selection

)

const

Definition at line 2418 of file kselectionproxymodel.cpp.

QModelIndex KSelectionProxyModel::mapToSource

(

const QModelIndex &

proxyIndex

)

const

Definition at line 2140 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 2368 of file kselectionproxymodel.cpp.

QMimeData * KSelectionProxyModel::mimeData ( const QModelIndexList &  indexes ) const

virtual

Definition at line 2268 of file kselectionproxymodel.cpp.

QStringList KSelectionProxyModel::mimeTypes ( ) const

virtual

Definition at line 2278 of file kselectionproxymodel.cpp.

QModelIndex KSelectionProxyModel::parent ( const QModelIndex &  index ) const

virtual

Definition at line 2224 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 2178 of file kselectionproxymodel.cpp.

QItemSelectionModel * KSelectionProxyModel::selectionModel

(

)

const

Definition at line 2329 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:

(root)
  - A
  - B
    - C
    - D
      - E
        - F
      - G
  - H
  - I
    - J
    - K
    - L

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

(root)
  - A
  - B
    - C
    - D
      - E
        - F
      - G

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:

(root)
  - A
  - C
  - D
    - E
      - F
    - G

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:

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

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 1998 of file kselectionproxymodel.cpp.

void KSelectionProxyModel::setSourceModel ( QAbstractItemModel *  sourceModel )

virtual

reimp.

Definition at line 2053 of file kselectionproxymodel.cpp.

QList< QPersistentModelIndex > KSelectionProxyModel::sourceRootIndexes ( ) const

protected

Definition at line 2362 of file kselectionproxymodel.cpp.

Qt::DropActions KSelectionProxyModel::supportedDropActions ( ) const

virtual

Definition at line 2285 of file kselectionproxymodel.cpp.

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

• kselectionproxymodel.h
• kselectionproxymodel.cpp