The QgsLayerTreeModel class is model implementation for Qt item views framework. More...

#include <qgslayertreemodel.h>

Inheritance diagram for QgsLayerTreeModel:

[legend]

Classes
struct	LayerLegendData
	Structure that stores all data associated with one map layer. More...

struct	LayerLegendTree
	Structure that stores tree representation of map layer's legend. More...

Public Types
enum	Flag { ShowLegend = 0x0001 , ShowLegendAsTree = 0x0004 , DeferredLegendInvalidation = 0x0008 , UseEmbeddedWidgets = 0x0010 , UseTextFormatting = 0x0020 , AllowNodeReorder = 0x1000 , AllowNodeRename = 0x2000 , AllowNodeChangeVisibility = 0x4000 , AllowLegendChangeState = 0x8000 , ActionHierarchical = 0x10000 , UseThreadedHitTest = 0x20000 }

Signals
void	hitTestCompleted ()
	Emitted when a hit test for visible legend items completes. More...

void	hitTestStarted ()
	Emitted when a hit test for visible legend items starts. More...

void	messageEmitted (const QString &message, Qgis::MessageLevel level=Qgis::MessageLevel::Info, int duration=5)
	Emits a message than can be displayed to the user in a GUI class. More...

Public Member Functions
	QgsLayerTreeModel (QgsLayerTree rootNode, QObject parent=nullptr)
	Construct a new tree model with given layer tree (root node must not be `nullptr`). More...

	~QgsLayerTreeModel () override

void	addTargetScreenProperties (const QgsScreenProperties &properties)
	Adds additional target screen properties to use when generating icons for Qt::DecorationRole data. More...

int	autoCollapseLegendNodes () const
	Returns at what number of legend nodes the layer node should be collapsed. -1 means no auto-collapse (default). More...

int	columnCount (const QModelIndex &parent=QModelIndex()) const override

QModelIndex	currentIndex () const
	Gets index of the item marked as current. Item marked as current is underlined. More...

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

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

const QgsLayerTreeFilterSettings *	filterSettings () const
	Returns the filter settings to use to filter legend nodes. More...

QgsLayerTreeModelLegendNode *	findLegendNode (const QString &layerId, const QString &ruleKey) const
	Searches through the layer tree to find a legend node with a matching layer ID and rule key. More...

Flags	flags () const
	Returns OR-ed combination of model flags. More...

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

bool	hitTestInProgress () const
	Returns `true` if a hit test for visible legend items is currently in progress. More...

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

QgsLayerTreeNode *	index2node (const QModelIndex &index) const
	Returns layer tree node for given index. More...

QList< QgsLayerTreeNode * >	indexes2nodes (const QModelIndexList &list, bool skipInternal=false) const
	Convert a list of indexes to a list of layer tree nodes. More...

QList< QgsLayerTreeModelLegendNode * >	layerLegendNodes (QgsLayerTreeLayer *nodeLayer, bool skipNodeEmbeddedInParent=false)
	Returns filtered list of active legend nodes attached to a particular layer node (by default it returns also legend node embedded in parent layer node (if any) unless skipNodeEmbeddedInParent is `true`) More...

QList< QgsLayerTreeModelLegendNode * >	layerOriginalLegendNodes (QgsLayerTreeLayer *nodeLayer)
	Returns original (unfiltered) list of legend nodes attached to a particular layer node. More...

QMap< QString, QString >	layerStyleOverrides () const
	Gets map of map layer style overrides (key: layer ID, value: style name) where a different style should be used instead of the current one. More...

QFont	layerTreeNodeFont (int nodeType) const
	Gets font for a particular type of layer tree node. nodeType should come from QgsLayerTreeNode::NodeType enumeration. More...

double	legendFilterByScale () const
	Returns the scale which restricts the legend nodes which are visible. More...

const QgsMapSettings *	legendFilterMapSettings () const
	Returns the current map settings used for the current legend filter (or `nullptr` if none is enabled) More...

void	legendMapViewData (double mapUnitsPerPixel, int dpi, double *scale) const
	Gets hints about map view - to be used in legend nodes. More...

QModelIndex	legendNode2index (QgsLayerTreeModelLegendNode *legendNode)
	Returns index for a given legend node. More...

QgsLayerTreeModelLegendNode *	legendNodeEmbeddedInParent (QgsLayerTreeLayer *nodeLayer) const
	Returns legend node that may be embedded in parent (i.e. More...

QMimeData *	mimeData (const QModelIndexList &indexes) const override

QStringList	mimeTypes () const override

QModelIndex	node2index (QgsLayerTreeNode *node) const
	Returns index for a given node. If the node does not belong to the layer tree, the result is undefined. More...

QModelIndex	parent (const QModelIndex &child) const override

void	refreshLayerLegend (QgsLayerTreeLayer *nodeLayer)
	Force a refresh of legend nodes of a layer node. More...

bool	removeRows (int row, int count, const QModelIndex &parent=QModelIndex()) override

QgsLayerTree *	rootGroup () const
	Returns pointer to the root node of the layer tree. Always a non `nullptr` value. More...

int	rowCount (const QModelIndex &parent=QModelIndex()) const override

void	setAutoCollapseLegendNodes (int nodeCount)
	Sets at what number of legend nodes the layer node should be collapsed. Setting -1 disables the auto-collapse (default). More...

void	setCurrentIndex (const QModelIndex &currentIndex)
	Sets index of the current item. May be used by view. Item marked as current is underlined. More...

bool	setData (const QModelIndex &index, const QVariant &value, int role=Qt::EditRole) override

void	setFilterSettings (const QgsLayerTreeFilterSettings *settings=nullptr)
	Sets the filter settings to use to filter legend nodes. More...

void	setFlag (Flag f, bool on=true)
	Enable or disable a model flag. More...

void	setFlags (QgsLayerTreeModel::Flags f)
	Sets OR-ed combination of model flags. More...

void	setLayerStyleOverrides (const QMap< QString, QString > &overrides)
	Sets map of map layer style overrides (key: layer ID, value: style name) where a different style should be used instead of the current one. More...

void	setLayerTreeNodeFont (int nodeType, const QFont &font)
	Sets font for a particular type of layer tree node. nodeType should come from QgsLayerTreeNode::NodeType enumeration. More...

Q_DECL_DEPRECATED void	setLegendFilter (const QgsMapSettings *settings, bool useExtent=true, const QgsGeometry &polygon=QgsGeometry(), bool useExpressions=true)
	Filter display of legend nodes for given map settings. More...

Q_DECL_DEPRECATED void	setLegendFilterByMap (const QgsMapSettings *settings)
	Force only display of legend nodes which are valid for given map settings. More...

void	setLegendFilterByScale (double scale)
	Force only display of legend nodes which are valid for a given scale. More...

void	setLegendMapViewData (double mapUnitsPerPixel, int dpi, double scale)
	Give the layer tree model hints about the currently associated map view so that legend nodes that use map units can be scaled correctly. More...

void	setRootGroup (QgsLayerTree *newRootGroup)
	Reset the model and use a new root group node. More...

Qt::DropActions	supportedDropActions () const override

QSet< QgsScreenProperties >	targetScreenProperties () const
	Returns the target screen properties to use when generating icons. More...

bool	testFlag (Flag f) const
	Check whether a flag is enabled. More...

void	waitForHitTestBlocking ()
	When a current hit test for visible legend items is in progress, calling this method will block until that hit test is complete. More...

Static Public Member Functions
static QgsLayerTreeModelLegendNode *	index2legendNode (const QModelIndex &index)
	Returns legend node for given index. More...

static int	scaleIconSize (int standardSize)
	Scales an layer tree model icon size to compensate for display pixel density, making the icon size hi-dpi friendly, whilst still resulting in pixel-perfect sizes for low-dpi displays. More...

Protected Slots
void	invalidateLegendMapBasedData ()

void	layerFlagsChanged ()
	Emitted when layer flags have changed. More...

void	layerLegendChanged ()

void	layerNeedsUpdate ()

void	legendNodeDataChanged ()

void	nodeAddedChildren (QgsLayerTreeNode *node, int indexFrom, int indexTo)

void	nodeCustomPropertyChanged (QgsLayerTreeNode *node, const QString &key)

void	nodeLayerLoaded ()

void	nodeLayerWillBeUnloaded ()

void	nodeNameChanged (QgsLayerTreeNode *node, const QString &name)
	Updates model when node's name has changed. More...

void	nodeRemovedChildren ()

void	nodeVisibilityChanged (QgsLayerTreeNode *node)

void	nodeWillAddChildren (QgsLayerTreeNode *node, int indexFrom, int indexTo)

void	nodeWillRemoveChildren (QgsLayerTreeNode *node, int indexFrom, int indexTo)

Protected Member Functions
void	addLegendToLayer (QgsLayerTreeLayer *nodeL)

void	connectToLayer (QgsLayerTreeLayer *nodeLayer)

void	connectToLayers (QgsLayerTreeGroup *parentGroup)

void	connectToRootNode ()

QgsRenderContext *	createTemporaryRenderContext () const
	Returns a temporary render context. More...

void	disconnectFromLayer (QgsLayerTreeLayer *nodeLayer)

void	disconnectFromLayers (QgsLayerTreeGroup *parentGroup)

void	disconnectFromRootNode ()

QList< QgsLayerTreeModelLegendNode * >	filterLegendNodes (const QList< QgsLayerTreeModelLegendNode * > &nodes)
	Filter nodes from QgsMapLayerLegend according to the current filtering rules. More...

QModelIndex	indexOfParentLayerTreeNode (QgsLayerTreeNode *parentNode) const

void	legendCleanup ()

bool	legendEmbeddedInParent (QgsLayerTreeLayer *nodeLayer) const

QIcon	legendIconEmbeddedInParent (QgsLayerTreeLayer *nodeLayer) const

void	legendInvalidateMapBasedData ()

QVariant	legendNodeData (QgsLayerTreeModelLegendNode *node, int role) const

Qt::ItemFlags	legendNodeFlags (QgsLayerTreeModelLegendNode *node) const

QModelIndex	legendNodeIndex (int row, int column, QgsLayerTreeModelLegendNode *node) const

int	legendNodeRowCount (QgsLayerTreeModelLegendNode *node) const

QModelIndex	legendParent (QgsLayerTreeModelLegendNode *legendNode) const

QModelIndex	legendRootIndex (int row, int column, QgsLayerTreeLayer *nL) const

int	legendRootRowCount (QgsLayerTreeLayer *nL) const

void	recursivelyEmitDataChanged (const QModelIndex &index=QModelIndex())
	emit dataChanged() for layer tree node items More...

void	refreshScaleBasedLayers (const QModelIndex &index=QModelIndex(), double previousScale=0.0)
	Updates layer data for scale dependent layers, should be called when map scale changes. More...

void	removeLegendFromLayer (QgsLayerTreeLayer *nodeLayer)

LayerLegendTree *	tryBuildLegendTree (const QList< QgsLayerTreeModelLegendNode * > &nodes)

Static Protected Member Functions
static QIcon	iconGroup ()

Protected Attributes
int	mAutoCollapseLegendNodesCount = -1
	Minimal number of nodes when legend should be automatically collapsed. -1 = disabled. More...

QPersistentModelIndex	mCurrentIndex
	Current index - will be underlined. More...

QTimer	mDeferLegendInvalidationTimer

std::unique_ptr< QgsLayerTreeFilterSettings >	mFilterSettings

Flags	mFlags
	Sets of flags for the model. More...

QFont	mFontGroup

QFont	mFontLayer

QMap< QString, QSet< QString > >	mHitTestResults

QPointer< QgsMapHitTestTask >	mHitTestTask

QSet< QgsLayerTreeLayer * >	mInvalidatedNodes
	Keep track of layer nodes for which the legend size needs to be recalculated. More...

QMap< QString, QString >	mLayerStyleOverrides
	Overrides of map layers' styles: key = layer ID, value = style XML. More...

QHash< QgsLayerTreeLayer *, LayerLegendData >	mLegend
	Per layer data about layer's legend nodes. More...

double	mLegendFilterByScale = 0
	scale denominator for filtering of legend nodes (<= 0 means no filtering) More...

int	mLegendMapViewDpi = 0

double	mLegendMapViewMupp = 0

double	mLegendMapViewScale = 0

QgsLayerTree *	mRootNode = nullptr
	Pointer to the root node of the layer tree. Not owned by the model. More...

QSet< QgsScreenProperties >	mTargetScreenProperties

Detailed Description

The QgsLayerTreeModel class is model implementation for Qt item views framework.

The model can be used in any QTreeView, it is however recommended to use it with QgsLayerTreeView which brings additional functionality specific to layer tree handling.

The model listens to the changes in the layer tree and signals the changes as appropriate, so that any view that uses the model is updated accordingly.

Behavior of the model can be customized with flags. For example, whether to show legend or whether to allow changes to the layer tree.

See also: QgsLayerTreeView

Since: QGIS 2.4

Definition at line 57 of file qgslayertreemodel.h.

Member Enumeration Documentation

◆ Flag

enum QgsLayerTreeModel::Flag

Enumerator
ShowLegend	Add legend nodes for layer nodes.
ShowLegendAsTree	For legends that support it, will show them in a tree instead of a list (needs also ShowLegend). Added in 2.8.
DeferredLegendInvalidation	Defer legend model invalidation.
UseEmbeddedWidgets	Layer nodes may optionally include extra embedded widgets (if used in QgsLayerTreeView). Added in 2.16.
UseTextFormatting	Layer nodes will alter text appearance based on layer properties, such as scale based visibility.
AllowNodeReorder	Allow reordering with drag'n'drop.
AllowNodeRename	Allow renaming of groups and layers.
AllowNodeChangeVisibility	Allow user to set node visibility with a checkbox.
AllowLegendChangeState	Allow check boxes for legend nodes (if supported by layer's legend)
ActionHierarchical	Check/uncheck action has consequences on children (or parents for leaf node)
UseThreadedHitTest	Run legend hit tests in a background thread (since QGIS 3.30)

Definition at line 97 of file qgslayertreemodel.h.

Constructor & Destructor Documentation

◆ QgsLayerTreeModel()

QgsLayerTreeModel::QgsLayerTreeModel	(	QgsLayerTree *	rootNode,
		QObject *	parent = `nullptr`
	)

explicit

Construct a new tree model with given layer tree (root node must not be nullptr).

The root node is not transferred by the model.

Definition at line 39 of file qgslayertreemodel.cpp.

◆ ~QgsLayerTreeModel()

QgsLayerTreeModel::~QgsLayerTreeModel ( )

override

Definition at line 52 of file qgslayertreemodel.cpp.

Member Function Documentation

◆ addLegendToLayer()

void QgsLayerTreeModel::addLegendToLayer ( QgsLayerTreeLayer * nodeL )

protected

Definition at line 1378 of file qgslayertreemodel.cpp.

◆ addTargetScreenProperties()

void QgsLayerTreeModel::addTargetScreenProperties ( const QgsScreenProperties & properties )

Adds additional target screen properties to use when generating icons for Qt::DecorationRole data.

This allows icons to be generated at an icon device pixel ratio and DPI which corresponds exactly to the view's screen properties in which this model is used.

Since: QGIS 3.32

Definition at line 740 of file qgslayertreemodel.cpp.

◆ autoCollapseLegendNodes()

int QgsLayerTreeModel::autoCollapseLegendNodes ( ) const

inline

Returns at what number of legend nodes the layer node should be collapsed. -1 means no auto-collapse (default).

Definition at line 213 of file qgslayertreemodel.h.

◆ columnCount()

int QgsLayerTreeModel::columnCount ( const QModelIndex & parent = QModelIndex() ) const

override

Definition at line 87 of file qgslayertreemodel.cpp.

◆ connectToLayer()

void QgsLayerTreeModel::connectToLayer ( QgsLayerTreeLayer * nodeLayer )

protected

Definition at line 950 of file qgslayertreemodel.cpp.

◆ connectToLayers()

void QgsLayerTreeModel::connectToLayers ( QgsLayerTreeGroup * parentGroup )

protected

Definition at line 1034 of file qgslayertreemodel.cpp.

◆ connectToRootNode()

void QgsLayerTreeModel::connectToRootNode ( )

protected

Definition at line 1058 of file qgslayertreemodel.cpp.

◆ createTemporaryRenderContext()

QgsRenderContext * QgsLayerTreeModel::createTemporaryRenderContext ( ) const

protected

Returns a temporary render context.

Note: Note available in Python bindings.

Definition at line 1514 of file qgslayertreemodel.cpp.

◆ currentIndex()

QModelIndex QgsLayerTreeModel::currentIndex ( ) const

Gets index of the item marked as current. Item marked as current is underlined.

Definition at line 538 of file qgslayertreemodel.cpp.

◆ data()

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

override

Definition at line 152 of file qgslayertreemodel.cpp.

◆ disconnectFromLayer()

void QgsLayerTreeModel::disconnectFromLayer ( QgsLayerTreeLayer * nodeLayer )

protected

Definition at line 1015 of file qgslayertreemodel.cpp.

◆ disconnectFromLayers()

void QgsLayerTreeModel::disconnectFromLayers ( QgsLayerTreeGroup * parentGroup )

protected

Definition at line 1046 of file qgslayertreemodel.cpp.

◆ disconnectFromRootNode()

void QgsLayerTreeModel::disconnectFromRootNode ( )

protected

Definition at line 1073 of file qgslayertreemodel.cpp.

◆ dropMimeData()

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

override

Definition at line 1165 of file qgslayertreemodel.cpp.

◆ filterLegendNodes()

QList< QgsLayerTreeModelLegendNode * > QgsLayerTreeModel::filterLegendNodes ( const QList< QgsLayerTreeModelLegendNode * > & nodes )

protected

Filter nodes from QgsMapLayerLegend according to the current filtering rules.

Definition at line 1275 of file qgslayertreemodel.cpp.

◆ filterSettings()

const QgsLayerTreeFilterSettings * QgsLayerTreeModel::filterSettings ( ) const

Returns the filter settings to use to filter legend nodes.

May be nullptr.

See also: setFilterSettings()

Since: QGIS 3.32

Definition at line 686 of file qgslayertreemodel.cpp.

◆ findLegendNode()

QgsLayerTreeModelLegendNode * QgsLayerTreeModel::findLegendNode	(	const QString &	layerId,
		const QString &	ruleKey
	)		const

Searches through the layer tree to find a legend node with a matching layer ID and rule key.

Parameters

layerId	map layer ID
ruleKey	legend node rule key

Returns: QgsLayerTreeModelLegendNode if found

Since: QGIS 2.14

Definition at line 1692 of file qgslayertreemodel.cpp.

◆ flags() [1/2]

QgsLayerTreeModel::Flags QgsLayerTreeModel::flags ( ) const

Returns OR-ed combination of model flags.

Definition at line 1260 of file qgslayertreemodel.cpp.

◆ flags() [2/2]

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

override

Definition at line 331 of file qgslayertreemodel.cpp.

◆ hitTestCompleted

void QgsLayerTreeModel::hitTestCompleted ( )

signal

Emitted when a hit test for visible legend items completes.

See also: hitTestInProgress(); hitTestStarted()

Since: QGIS 3.32

◆ hitTestInProgress()

bool QgsLayerTreeModel::hitTestInProgress ( ) const

Returns true if a hit test for visible legend items is currently in progress.

See also: hitTestStarted(); hitTestCompleted()

Since: QGIS 3.32

Definition at line 764 of file qgslayertreemodel.cpp.

◆ hitTestStarted

void QgsLayerTreeModel::hitTestStarted ( )

signal

Emitted when a hit test for visible legend items starts.

See also: hitTestInProgress(); hitTestCompleted()

Since: QGIS 3.32

◆ iconGroup()

QIcon QgsLayerTreeModel::iconGroup ( )

staticprotected

Definition at line 1270 of file qgslayertreemodel.cpp.

◆ index()

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

override

Definition at line 93 of file qgslayertreemodel.cpp.

◆ index2legendNode()

QgsLayerTreeModelLegendNode * QgsLayerTreeModel::index2legendNode ( const QModelIndex & index )

static

Returns legend node for given index.

Returns nullptr for invalid index

Since: QGIS 2.6

Definition at line 1538 of file qgslayertreemodel.cpp.

◆ index2node()

QgsLayerTreeNode * QgsLayerTreeModel::index2node ( const QModelIndex & index ) const

Returns layer tree node for given index.

Returns root node for invalid index. Returns nullptr if index does not refer to a layer tree node (e.g. it is a legend node)

Definition at line 57 of file qgslayertreemodel.cpp.

◆ indexes2nodes()

QList< QgsLayerTreeNode * > QgsLayerTreeModel::indexes2nodes	(	const QModelIndexList &	list,
		bool	skipInternal = `false`
	)		const

Convert a list of indexes to a list of layer tree nodes.

Indices that do not represent layer tree nodes are skipped. If skipInternal is true, a node is included in the output list only if no parent node is in the list.

Definition at line 468 of file qgslayertreemodel.cpp.

◆ indexOfParentLayerTreeNode()

QModelIndex QgsLayerTreeModel::indexOfParentLayerTreeNode ( QgsLayerTreeNode * parentNode ) const

protected

Definition at line 137 of file qgslayertreemodel.cpp.

◆ invalidateLegendMapBasedData

void QgsLayerTreeModel::invalidateLegendMapBasedData ( )

protectedslot

Definition at line 1722 of file qgslayertreemodel.cpp.

◆ layerFlagsChanged

void QgsLayerTreeModel::layerFlagsChanged ( )

protectedslot

Emitted when layer flags have changed.

Since: QGIS 3.18

Definition at line 883 of file qgslayertreemodel.cpp.

◆ layerLegendChanged

void QgsLayerTreeModel::layerLegendChanged ( )

protectedslot

Definition at line 864 of file qgslayertreemodel.cpp.

◆ layerLegendNodes()

QList< QgsLayerTreeModelLegendNode * > QgsLayerTreeModel::layerLegendNodes	(	QgsLayerTreeLayer *	nodeLayer,
		bool	skipNodeEmbeddedInParent = `false`
	)

Returns filtered list of active legend nodes attached to a particular layer node (by default it returns also legend node embedded in parent layer node (if any) unless skipNodeEmbeddedInParent is true)

Note: Parameter skipNodeEmbeddedInParent added in QGIS 2.18

See also: layerOriginalLegendNodes()

Since: QGIS 2.6

Definition at line 1675 of file qgslayertreemodel.cpp.

◆ layerNeedsUpdate

void QgsLayerTreeModel::layerNeedsUpdate ( )

protectedslot

Definition at line 900 of file qgslayertreemodel.cpp.

◆ layerOriginalLegendNodes()

QList< QgsLayerTreeModelLegendNode * > QgsLayerTreeModel::layerOriginalLegendNodes ( QgsLayerTreeLayer * nodeLayer )

Returns original (unfiltered) list of legend nodes attached to a particular layer node.

See also: layerLegendNodes()

Since: QGIS 2.14

Definition at line 1687 of file qgslayertreemodel.cpp.

◆ layerStyleOverrides()

QMap< QString, QString > QgsLayerTreeModel::layerStyleOverrides ( ) const

Gets map of map layer style overrides (key: layer ID, value: style name) where a different style should be used instead of the current one.

Since: QGIS 2.10

Definition at line 730 of file qgslayertreemodel.cpp.

◆ layerTreeNodeFont()

QFont QgsLayerTreeModel::layerTreeNodeFont ( int nodeType ) const

Gets font for a particular type of layer tree node. nodeType should come from QgsLayerTreeNode::NodeType enumeration.

Definition at line 574 of file qgslayertreemodel.cpp.

◆ legendCleanup()

void QgsLayerTreeModel::legendCleanup ( )

protected

Definition at line 1347 of file qgslayertreemodel.cpp.

◆ legendEmbeddedInParent()

bool QgsLayerTreeModel::legendEmbeddedInParent ( QgsLayerTreeLayer * nodeLayer ) const

protected

Definition at line 1655 of file qgslayertreemodel.cpp.

◆ legendFilterByScale()

double QgsLayerTreeModel::legendFilterByScale ( ) const

inline

Returns the scale which restricts the legend nodes which are visible.

The scale value indicates the scale denominator, e.g. 1000.0 for a 1:1000 map. A scale <= 0 indicates that no scale filtering is being performed.

See also: setLegendFilterByScale()

Since: QGIS 2.6

Definition at line 231 of file qgslayertreemodel.h.

◆ legendFilterMapSettings()

const QgsMapSettings * QgsLayerTreeModel::legendFilterMapSettings ( ) const

Returns the current map settings used for the current legend filter (or nullptr if none is enabled)

Since: QGIS 2.14

Definition at line 633 of file qgslayertreemodel.cpp.

◆ legendIconEmbeddedInParent()

QIcon QgsLayerTreeModel::legendIconEmbeddedInParent ( QgsLayerTreeLayer * nodeLayer ) const

protected

Definition at line 1666 of file qgslayertreemodel.cpp.

◆ legendInvalidateMapBasedData()

void QgsLayerTreeModel::legendInvalidateMapBasedData ( )

protected

Definition at line 1714 of file qgslayertreemodel.cpp.

◆ legendMapViewData()

void QgsLayerTreeModel::legendMapViewData	(	double *	mapUnitsPerPixel,
		int *	dpi,
		double *	scale
	)		const

Gets hints about map view - to be used in legend nodes.

Arguments that are not nullptr will receive values. If there are no valid map view data (from previous call to setLegendMapViewData()), returned values are zeros.

Since: QGIS 2.6

Definition at line 723 of file qgslayertreemodel.cpp.

◆ legendNode2index()

QModelIndex QgsLayerTreeModel::legendNode2index ( QgsLayerTreeModelLegendNode * legendNode )

Returns index for a given legend node.

If the legend node does not belong to the layer tree, the result is undefined. If the legend node is belongs to the tree but it is filtered out, invalid model index is returned.

Since: QGIS 2.6

Definition at line 1544 of file qgslayertreemodel.cpp.

◆ legendNodeData()

QVariant QgsLayerTreeModel::legendNodeData	(	QgsLayerTreeModelLegendNode *	node,
		int	role
	)		const

protected

Definition at line 1638 of file qgslayertreemodel.cpp.

◆ legendNodeDataChanged

void QgsLayerTreeModel::legendNodeDataChanged ( )

protectedslot

Definition at line 918 of file qgslayertreemodel.cpp.

◆ legendNodeEmbeddedInParent()

QgsLayerTreeModelLegendNode * QgsLayerTreeModel::legendNodeEmbeddedInParent ( QgsLayerTreeLayer * nodeLayer ) const

Returns legend node that may be embedded in parent (i.e.

its icon will be used for layer's icon).

Since: QGIS 2.18

Definition at line 1660 of file qgslayertreemodel.cpp.

◆ legendNodeFlags()

Qt::ItemFlags QgsLayerTreeModel::legendNodeFlags ( QgsLayerTreeModelLegendNode * node ) const

protected

Definition at line 1646 of file qgslayertreemodel.cpp.

◆ legendNodeIndex()

QModelIndex QgsLayerTreeModel::legendNodeIndex	(	int	row,
		int	column,
		QgsLayerTreeModelLegendNode *	node
	)		const

protected

Definition at line 1608 of file qgslayertreemodel.cpp.

◆ legendNodeRowCount()

int QgsLayerTreeModel::legendNodeRowCount ( QgsLayerTreeModelLegendNode * node ) const

protected

Definition at line 1573 of file qgslayertreemodel.cpp.

◆ legendParent()

QModelIndex QgsLayerTreeModel::legendParent ( QgsLayerTreeModelLegendNode * legendNode ) const

protected

Definition at line 1618 of file qgslayertreemodel.cpp.

◆ legendRootIndex()

QModelIndex QgsLayerTreeModel::legendRootIndex	(	int	row,
		int	column,
		QgsLayerTreeLayer *	nL
	)		const

protected

Definition at line 1597 of file qgslayertreemodel.cpp.

◆ legendRootRowCount()

int QgsLayerTreeModel::legendRootRowCount ( QgsLayerTreeLayer * nL ) const

protected

Definition at line 1583 of file qgslayertreemodel.cpp.

◆ messageEmitted

void QgsLayerTreeModel::messageEmitted	(	const QString &	message,
		Qgis::MessageLevel	level = `Qgis::MessageLevel::Info`,
		int	duration = `5`
	)

signal

Emits a message than can be displayed to the user in a GUI class.

Since: QGIS 3.14

◆ mimeData()

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

override

Definition at line 1127 of file qgslayertreemodel.cpp.

◆ mimeTypes()

QStringList QgsLayerTreeModel::mimeTypes ( ) const

override

Definition at line 1119 of file qgslayertreemodel.cpp.

◆ node2index()

QModelIndex QgsLayerTreeModel::node2index ( QgsLayerTreeNode * node ) const

Returns index for a given node. If the node does not belong to the layer tree, the result is undefined.

Definition at line 432 of file qgslayertreemodel.cpp.

◆ nodeAddedChildren

void QgsLayerTreeModel::nodeAddedChildren	(	QgsLayerTreeNode *	node,
		int	indexFrom,
		int	indexTo
	)

protectedslot

Definition at line 789 of file qgslayertreemodel.cpp.

◆ nodeCustomPropertyChanged

void QgsLayerTreeModel::nodeCustomPropertyChanged	(	QgsLayerTreeNode *	node,
		const QString &	key
	)

protectedslot

Definition at line 835 of file qgslayertreemodel.cpp.

◆ nodeLayerLoaded

void QgsLayerTreeModel::nodeLayerLoaded ( )

protectedslot

Definition at line 842 of file qgslayertreemodel.cpp.

◆ nodeLayerWillBeUnloaded

void QgsLayerTreeModel::nodeLayerWillBeUnloaded ( )

protectedslot

Definition at line 852 of file qgslayertreemodel.cpp.

◆ nodeNameChanged

void QgsLayerTreeModel::nodeNameChanged	(	QgsLayerTreeNode *	node,
		const QString &	name
	)

protectedslot

Updates model when node's name has changed.

Since: QGIS 3.0

Definition at line 825 of file qgslayertreemodel.cpp.

◆ nodeRemovedChildren

void QgsLayerTreeModel::nodeRemovedChildren ( )

protectedslot

Definition at line 812 of file qgslayertreemodel.cpp.

◆ nodeVisibilityChanged

void QgsLayerTreeModel::nodeVisibilityChanged ( QgsLayerTreeNode * node )

protectedslot

Definition at line 817 of file qgslayertreemodel.cpp.

◆ nodeWillAddChildren

void QgsLayerTreeModel::nodeWillAddChildren	(	QgsLayerTreeNode *	node,
		int	indexFrom,
		int	indexTo
	)

protectedslot

Definition at line 769 of file qgslayertreemodel.cpp.

◆ nodeWillRemoveChildren

void QgsLayerTreeModel::nodeWillRemoveChildren	(	QgsLayerTreeNode *	node,
		int	indexFrom,
		int	indexTo
	)

protectedslot

Definition at line 800 of file qgslayertreemodel.cpp.

◆ parent()

QModelIndex QgsLayerTreeModel::parent ( const QModelIndex & child ) const

override

Definition at line 115 of file qgslayertreemodel.cpp.

◆ recursivelyEmitDataChanged()

void QgsLayerTreeModel::recursivelyEmitDataChanged ( const QModelIndex & index = QModelIndex() )

protected

emit dataChanged() for layer tree node items

Definition at line 1080 of file qgslayertreemodel.cpp.

◆ refreshLayerLegend()

void QgsLayerTreeModel::refreshLayerLegend ( QgsLayerTreeLayer * nodeLayer )

Force a refresh of legend nodes of a layer node.

Not necessary to call when layer's renderer is changed as the model listens to these events.

Definition at line 515 of file qgslayertreemodel.cpp.

◆ refreshScaleBasedLayers()

void QgsLayerTreeModel::refreshScaleBasedLayers	(	const QModelIndex &	index = `QModelIndex()`,
		double	previousScale = `0.0`
	)

protected

Updates layer data for scale dependent layers, should be called when map scale changes.

Emits dataChanged() for all scale dependent layers.

Since: QGIS 2.16

Definition at line 1094 of file qgslayertreemodel.cpp.

◆ removeLegendFromLayer()

void QgsLayerTreeModel::removeLegendFromLayer ( QgsLayerTreeLayer * nodeLayer )

protected

Definition at line 1367 of file qgslayertreemodel.cpp.

◆ removeRows()

bool QgsLayerTreeModel::removeRows	(	int	row,
		int	count,
		const QModelIndex &	parent = `QModelIndex()`
	)

override

Definition at line 1236 of file qgslayertreemodel.cpp.

◆ rootGroup()

QgsLayerTree * QgsLayerTreeModel::rootGroup ( ) const

Returns pointer to the root node of the layer tree. Always a non nullptr value.

Definition at line 495 of file qgslayertreemodel.cpp.

◆ rowCount()

int QgsLayerTreeModel::rowCount ( const QModelIndex & parent = QModelIndex() ) const

override

Definition at line 67 of file qgslayertreemodel.cpp.

◆ scaleIconSize()

int QgsLayerTreeModel::scaleIconSize ( int standardSize )

static

Scales an layer tree model icon size to compensate for display pixel density, making the icon size hi-dpi friendly, whilst still resulting in pixel-perfect sizes for low-dpi displays.

standardSize should be set to a standard icon size, e.g. 16, 24, 48, etc.

Since: QGIS 3.6

Definition at line 753 of file qgslayertreemodel.cpp.

◆ setAutoCollapseLegendNodes()

void QgsLayerTreeModel::setAutoCollapseLegendNodes ( int nodeCount )

inline

Sets at what number of legend nodes the layer node should be collapsed. Setting -1 disables the auto-collapse (default).

Definition at line 211 of file qgslayertreemodel.h.

◆ setCurrentIndex()

void QgsLayerTreeModel::setCurrentIndex ( const QModelIndex & currentIndex )

Sets index of the current item. May be used by view. Item marked as current is underlined.

Definition at line 543 of file qgslayertreemodel.cpp.

◆ setData()

bool QgsLayerTreeModel::setData	(	const QModelIndex &	index,
		const QVariant &	value,
		int	role = `Qt::EditRole`
	)

override

Definition at line 368 of file qgslayertreemodel.cpp.

◆ setFilterSettings()

void QgsLayerTreeModel::setFilterSettings ( const QgsLayerTreeFilterSettings * settings = nullptr )

Sets the filter settings to use to filter legend nodes.

Set to nullptr to disable legend filter.

See also: filterSettings()

Since: QGIS 3.32

Definition at line 638 of file qgslayertreemodel.cpp.

◆ setFlag()

void QgsLayerTreeModel::setFlag	(	QgsLayerTreeModel::Flag	f,
		bool	on = `true`
	)

Enable or disable a model flag.

Definition at line 1252 of file qgslayertreemodel.cpp.

◆ setFlags()

void QgsLayerTreeModel::setFlags ( QgsLayerTreeModel::Flags f )

Sets OR-ed combination of model flags.

Definition at line 1247 of file qgslayertreemodel.cpp.

◆ setLayerStyleOverrides()

void QgsLayerTreeModel::setLayerStyleOverrides ( const QMap< QString, QString > & overrides )

Sets map of map layer style overrides (key: layer ID, value: style name) where a different style should be used instead of the current one.

Since: QGIS 2.10

Definition at line 735 of file qgslayertreemodel.cpp.

◆ setLayerTreeNodeFont()

void QgsLayerTreeModel::setLayerTreeNodeFont	(	int	nodeType,
		const QFont &	font
	)

Sets font for a particular type of layer tree node. nodeType should come from QgsLayerTreeNode::NodeType enumeration.

Definition at line 549 of file qgslayertreemodel.cpp.

◆ setLegendFilter()

void QgsLayerTreeModel::setLegendFilter	(	const QgsMapSettings *	settings,
		bool	useExtent = `true`,
		const QgsGeometry &	polygon = `QgsGeometry()`,
		bool	useExpressions = `true`
	)

Filter display of legend nodes for given map settings.

Parameters

settings	Map settings. Setting `nullptr` or invalid settings will disable any filter. Ownership is not changed, a copy is made
useExtent	Whether to use the extent of the map settings as a first spatial filter on legend nodes
polygon	If not empty, this polygon will be used instead of the map extent to filter legend nodes
useExpressions	Whether to use legend node filter expressions

Deprecated:: QGIS 3.32. Use setFilterSettings() instead.

Definition at line 605 of file qgslayertreemodel.cpp.

◆ setLegendFilterByMap()

void QgsLayerTreeModel::setLegendFilterByMap ( const QgsMapSettings * settings )

Force only display of legend nodes which are valid for given map settings.

Setting nullptr or invalid map settings will disable the functionality. Ownership of map settings pointer does not change, a copy is made.

Deprecated:: QGIS 3.32. Use setFilterSettings() instead.

Definition at line 598 of file qgslayertreemodel.cpp.

◆ setLegendFilterByScale()

void QgsLayerTreeModel::setLegendFilterByScale ( double scale )

Force only display of legend nodes which are valid for a given scale.

The scale value indicates the scale denominator, e.g. 1000.0 for a 1:1000 map. Setting scale <= 0 will disable the functionality.

See also: legendFilterByScale()

Since: QGIS 2.6

Definition at line 587 of file qgslayertreemodel.cpp.

◆ setLegendMapViewData()

void QgsLayerTreeModel::setLegendMapViewData	(	double	mapUnitsPerPixel,
		int	dpi,
		double	scale
	)

Give the layer tree model hints about the currently associated map view so that legend nodes that use map units can be scaled correctly.

Since: QGIS 2.6

Definition at line 706 of file qgslayertreemodel.cpp.

◆ setRootGroup()

void QgsLayerTreeModel::setRootGroup ( QgsLayerTree * newRootGroup )

Reset the model and use a new root group node.

Since: QGIS 2.6

Definition at line 500 of file qgslayertreemodel.cpp.

◆ supportedDropActions()

Qt::DropActions QgsLayerTreeModel::supportedDropActions ( ) const

override

Definition at line 1114 of file qgslayertreemodel.cpp.

◆ targetScreenProperties()

QSet< QgsScreenProperties > QgsLayerTreeModel::targetScreenProperties ( ) const

Returns the target screen properties to use when generating icons.

This allows icons to be generated at an icon device pixel ratio and DPI which corresponds exactly to the view's screen properties in which this model is used.

See also: addTargetScreenProperties()

Since: QGIS 3.32

Definition at line 748 of file qgslayertreemodel.cpp.

◆ testFlag()

bool QgsLayerTreeModel::testFlag ( QgsLayerTreeModel::Flag f ) const

Check whether a flag is enabled.

Definition at line 1265 of file qgslayertreemodel.cpp.

◆ tryBuildLegendTree()

QgsLayerTreeModel::LayerLegendTree * QgsLayerTreeModel::tryBuildLegendTree ( const QList< QgsLayerTreeModelLegendNode * > & nodes )

protected

Note: not available in Python bindings

Definition at line 1474 of file qgslayertreemodel.cpp.

◆ waitForHitTestBlocking()

void QgsLayerTreeModel::waitForHitTestBlocking ( )

When a current hit test for visible legend items is in progress, calling this method will block until that hit test is complete.

Since: QGIS 3.32

Definition at line 758 of file qgslayertreemodel.cpp.

Member Data Documentation

◆ mAutoCollapseLegendNodesCount

int QgsLayerTreeModel::mAutoCollapseLegendNodesCount = -1

protected

Minimal number of nodes when legend should be automatically collapsed. -1 = disabled.

Definition at line 470 of file qgslayertreemodel.h.

◆ mCurrentIndex

QPersistentModelIndex QgsLayerTreeModel::mCurrentIndex

protected

Current index - will be underlined.

Definition at line 468 of file qgslayertreemodel.h.

◆ mDeferLegendInvalidationTimer

QTimer QgsLayerTreeModel::mDeferLegendInvalidationTimer

protected

Definition at line 557 of file qgslayertreemodel.h.

◆ mFilterSettings

std::unique_ptr< QgsLayerTreeFilterSettings > QgsLayerTreeModel::mFilterSettings

protected

Definition at line 552 of file qgslayertreemodel.h.

◆ mFlags

Flags QgsLayerTreeModel::mFlags

protected

Sets of flags for the model.

Definition at line 466 of file qgslayertreemodel.h.

◆ mFontGroup

QFont QgsLayerTreeModel::mFontGroup

protected

Definition at line 543 of file qgslayertreemodel.h.

◆ mFontLayer

QFont QgsLayerTreeModel::mFontLayer

protected

Definition at line 542 of file qgslayertreemodel.h.

◆ mHitTestResults

QMap<QString, QSet<QString> > QgsLayerTreeModel::mHitTestResults

protected

Definition at line 550 of file qgslayertreemodel.h.

◆ mHitTestTask

QPointer< QgsMapHitTestTask > QgsLayerTreeModel::mHitTestTask

protected

Definition at line 548 of file qgslayertreemodel.h.

◆ mInvalidatedNodes

QSet<QgsLayerTreeLayer *> QgsLayerTreeModel::mInvalidatedNodes

protected

Keep track of layer nodes for which the legend size needs to be recalculated.

Definition at line 540 of file qgslayertreemodel.h.

◆ mLayerStyleOverrides

QMap<QString, QString> QgsLayerTreeModel::mLayerStyleOverrides

protected

Overrides of map layers' styles: key = layer ID, value = style XML.

This allows showing a legend that is different from the current style of layers

Definition at line 531 of file qgslayertreemodel.h.

◆ mLegend

QHash<QgsLayerTreeLayer *, LayerLegendData> QgsLayerTreeModel::mLegend

protected

Per layer data about layer's legend nodes.

Definition at line 534 of file qgslayertreemodel.h.

◆ mLegendFilterByScale

double QgsLayerTreeModel::mLegendFilterByScale = 0

protected

scale denominator for filtering of legend nodes (<= 0 means no filtering)

Definition at line 546 of file qgslayertreemodel.h.

◆ mLegendMapViewDpi

int QgsLayerTreeModel::mLegendMapViewDpi = 0

protected

Definition at line 555 of file qgslayertreemodel.h.

◆ mLegendMapViewMupp

double QgsLayerTreeModel::mLegendMapViewMupp = 0

protected

Definition at line 554 of file qgslayertreemodel.h.

◆ mLegendMapViewScale

double QgsLayerTreeModel::mLegendMapViewScale = 0

protected

Definition at line 556 of file qgslayertreemodel.h.

◆ mRootNode

QgsLayerTree* QgsLayerTreeModel::mRootNode = nullptr

protected

Pointer to the root node of the layer tree. Not owned by the model.

Definition at line 464 of file qgslayertreemodel.h.

◆ mTargetScreenProperties

QSet< QgsScreenProperties > QgsLayerTreeModel::mTargetScreenProperties

protected

Definition at line 559 of file qgslayertreemodel.h.

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

/build/qgis-3.32.0+99sid/src/core/layertree/qgslayertreemodel.h
/build/qgis-3.32.0+99sid/src/core/layertree/qgslayertreemodel.cpp

Classes

Public Types

Signals

Public Member Functions

Static Public Member Functions

Protected Slots

Protected Member Functions

Static Protected Member Functions

Protected Attributes

Detailed Description

Member Enumeration Documentation

◆ Flag

Constructor & Destructor Documentation

◆ QgsLayerTreeModel()

◆ ~QgsLayerTreeModel()

Member Function Documentation

◆ addLegendToLayer()

◆ addTargetScreenProperties()

◆ autoCollapseLegendNodes()

◆ columnCount()

◆ connectToLayer()

◆ connectToLayers()

◆ connectToRootNode()

◆ createTemporaryRenderContext()

◆ currentIndex()

◆ data()

◆ disconnectFromLayer()

◆ disconnectFromLayers()

◆ disconnectFromRootNode()

◆ dropMimeData()

◆ filterLegendNodes()

◆ filterSettings()

◆ findLegendNode()

◆ flags() [1/2]

◆ flags() [2/2]

◆ hitTestCompleted

◆ hitTestInProgress()

◆ hitTestStarted

◆ iconGroup()

◆ index()

◆ index2legendNode()

◆ index2node()

◆ indexes2nodes()

◆ indexOfParentLayerTreeNode()

◆ invalidateLegendMapBasedData

◆ layerFlagsChanged

◆ layerLegendChanged

◆ layerLegendNodes()

◆ layerNeedsUpdate

◆ layerOriginalLegendNodes()

◆ layerStyleOverrides()

◆ layerTreeNodeFont()

◆ legendCleanup()

◆ legendEmbeddedInParent()

◆ legendFilterByScale()

◆ legendFilterMapSettings()

◆ legendIconEmbeddedInParent()

◆ legendInvalidateMapBasedData()

◆ legendMapViewData()

◆ legendNode2index()

◆ legendNodeData()

◆ legendNodeDataChanged

◆ legendNodeEmbeddedInParent()

◆ legendNodeFlags()

◆ legendNodeIndex()

◆ legendNodeRowCount()

◆ legendParent()

◆ legendRootIndex()

◆ legendRootRowCount()

◆ messageEmitted

◆ mimeData()

◆ mimeTypes()

◆ node2index()

◆ nodeAddedChildren

◆ nodeCustomPropertyChanged

◆ nodeLayerLoaded

◆ nodeLayerWillBeUnloaded

◆ nodeNameChanged

◆ nodeRemovedChildren

◆ nodeVisibilityChanged