QGIS API Documentation  3.17.0-Master (7a14973234)
Classes | Public Types | Signals | Public Member Functions | Protected Member Functions | Protected Attributes | List of all members
QgsLayerTreeModelLegendNode Class Referenceabstract

The QgsLegendRendererItem class is abstract interface for legend items returned from QgsMapLayerLegend implementation. More...

#include <qgslayertreemodellegendnode.h>

Inheritance diagram for QgsLayerTreeModelLegendNode:
Inheritance graph
[legend]

Classes

struct  ItemContext
 
struct  ItemMetrics
 

Public Types

enum  LegendNodeRoles { RuleKeyRole = Qt::UserRole, ParentRuleKeyRole }
 

Signals

void dataChanged ()
 Emitted on internal data change so the layer tree model can forward the signal to views. More...
 
void sizeChanged ()
 Emitted when the size of this node changes. More...
 

Public Member Functions

virtual bool columnBreak () const
 Returns whether a forced column break should occur before the node. More...
 
virtual QVariant data (int role) const =0
 Returns data associated with the item. Must be implemented in derived class. More...
 
virtual ItemMetrics draw (const QgsLegendSettings &settings, ItemContext *ctx)
 Entry point called from QgsLegendRenderer to do the rendering. More...
 
virtual QSizeF drawSymbol (const QgsLegendSettings &settings, ItemContext *ctx, double itemHeight) const
 Draws symbol on the left side of the item. More...
 
virtual QSizeF drawSymbolText (const QgsLegendSettings &settings, ItemContext *ctx, QSizeF symbolSize) const
 Draws label on the right side of the item. More...
 
virtual QJsonObject exportSymbolToJson (const QgsLegendSettings &settings, const QgsRenderContext &context) const
 Adds a symbol in base64 string within a JSON object with the key "icon". More...
 
QJsonObject exportToJson (const QgsLegendSettings &settings, const QgsRenderContext &context)
 Entry point called from QgsLegendRenderer to do the rendering in a JSON object. More...
 
virtual Qt::ItemFlags flags () const
 Returns item flags associated with the item. Default implementation returns Qt::ItemIsEnabled. More...
 
virtual void invalidateMapBasedData ()
 Notification from model that information from associated map view has changed. More...
 
virtual bool isEmbeddedInParent () const
 
virtual bool isScaleOK (double scale) const
 
QgsLayerTreeLayerlayerNode () const
 Returns pointer to the parent layer node. More...
 
QgsLayerTreeModelmodel () const
 Returns pointer to model owning this legend node. More...
 
virtual void setColumnBreak (bool breakBeforeNode)
 Sets whether a forced column break should occur before the node. More...
 
virtual bool setData (const QVariant &value, int role)
 Sets some data associated with the item. Default implementation does nothing and returns false. More...
 
virtual void setEmbeddedInParent (bool embedded)
 
virtual void setUserLabel (const QString &userLabel)
 
virtual void setUserPatchSize (QSizeF size)
 Sets the user (overridden) size for the legend node. More...
 
virtual QString userLabel () const
 
virtual QSizeF userPatchSize () const
 Returns the user (overridden) size for the legend node. More...
 

Protected Member Functions

 QgsLayerTreeModelLegendNode (QgsLayerTreeLayer *nodeL, QObject *parent=nullptr)
 Construct the node with pointer to its parent layer node. More...
 
QgsRenderContextcreateTemporaryRenderContext () const
 Returns a temporary context or nullptr if legendMapViewData are not valid. More...
 

Protected Attributes

bool mColumnBreakBeforeNode = false
 
bool mEmbeddedInParent
 
QgsLayerTreeLayermLayerNode = nullptr
 
QgsLegendPatchShape mPatchShape
 
QString mUserLabel
 
QSizeF mUserSize
 

Detailed Description

The QgsLegendRendererItem class is abstract interface for legend items returned from QgsMapLayerLegend implementation.

The objects are used in QgsLayerTreeModel. Custom implementations may offer additional interactivity and customized look.

Since
QGIS 2.6

Definition at line 50 of file qgslayertreemodellegendnode.h.

Member Enumeration Documentation

◆ LegendNodeRoles

Enumerator
RuleKeyRole 

Rule key of the node (QString)

ParentRuleKeyRole 

Rule key of the parent legend node - for legends with tree hierarchy (QString). Added in 2.8.

Definition at line 63 of file qgslayertreemodellegendnode.h.

Constructor & Destructor Documentation

◆ QgsLayerTreeModelLegendNode()

QgsLayerTreeModelLegendNode::QgsLayerTreeModelLegendNode ( QgsLayerTreeLayer nodeL,
QObject *  parent = nullptr 
)
explicitprotected

Construct the node with pointer to its parent layer node.

Definition at line 39 of file qgslayertreemodellegendnode.cpp.

Member Function Documentation

◆ columnBreak()

virtual bool QgsLayerTreeModelLegendNode::columnBreak ( ) const
inlinevirtual

Returns whether a forced column break should occur before the node.

See also
setColumnBreak()
Since
QGIS 3.14

Definition at line 126 of file qgslayertreemodellegendnode.h.

◆ createTemporaryRenderContext()

QgsRenderContext * QgsLayerTreeModelLegendNode::createTemporaryRenderContext ( ) const
protected

Returns a temporary context or nullptr if legendMapViewData are not valid.

Definition at line 400 of file qgslayertreemodellegendnode.cpp.

◆ data()

virtual QVariant QgsLayerTreeModelLegendNode::data ( int  role) const
pure virtual

Returns data associated with the item. Must be implemented in derived class.

Implemented in QgsDataDefinedSizeLegendNode, QgsWmsLegendNode, QgsRasterSymbolLegendNode, QgsImageLegendNode, QgsSimpleLegendNode, and QgsSymbolLegendNode.

◆ dataChanged

void QgsLayerTreeModelLegendNode::dataChanged ( )
signal

Emitted on internal data change so the layer tree model can forward the signal to views.

◆ draw()

QgsLayerTreeModelLegendNode::ItemMetrics QgsLayerTreeModelLegendNode::draw ( const QgsLegendSettings settings,
ItemContext ctx 
)
virtual

Entry point called from QgsLegendRenderer to do the rendering.

Default implementation calls drawSymbol() and drawSymbolText() methods.

If ctx is nullptr, this is just first stage when preparing layout - without actual rendering.

Reimplemented in QgsDataDefinedSizeLegendNode.

Definition at line 80 of file qgslayertreemodellegendnode.cpp.

◆ drawSymbol()

QSizeF QgsLayerTreeModelLegendNode::drawSymbol ( const QgsLegendSettings settings,
ItemContext ctx,
double  itemHeight 
) const
virtual

Draws symbol on the left side of the item.

Parameters
settingsLegend layout configuration
ctxContext for rendering - may be nullptr if only doing layout without actual rendering
itemHeightMinimal height of the legend item - used for correct positioning when rendering
Returns
Real size of the symbol (may be bigger than "normal" symbol size from settings)

Reimplemented in QgsWmsLegendNode, QgsRasterSymbolLegendNode, QgsImageLegendNode, and QgsSymbolLegendNode.

Definition at line 104 of file qgslayertreemodellegendnode.cpp.

◆ drawSymbolText()

QSizeF QgsLayerTreeModelLegendNode::drawSymbolText ( const QgsLegendSettings settings,
ItemContext ctx,
QSizeF  symbolSize 
) const
virtual

Draws label on the right side of the item.

Parameters
settingsLegend layout configuration
ctxContext for rendering - may be nullptr if only doing layout without actual rendering
symbolSizeReal size of the associated symbol - used for correct positioning when rendering
Returns
Size of the label (may span multiple lines)

Definition at line 161 of file qgslayertreemodellegendnode.cpp.

◆ exportSymbolToJson()

QJsonObject QgsLayerTreeModelLegendNode::exportSymbolToJson ( const QgsLegendSettings settings,
const QgsRenderContext context 
) const
virtual

Adds a symbol in base64 string within a JSON object with the key "icon".

Parameters
settingsLegend layout configuration
contextRendering context
Since
QGIS 3.8

Reimplemented in QgsWmsLegendNode, QgsRasterSymbolLegendNode, QgsImageLegendNode, and QgsSymbolLegendNode.

Definition at line 144 of file qgslayertreemodellegendnode.cpp.

◆ exportToJson()

QJsonObject QgsLayerTreeModelLegendNode::exportToJson ( const QgsLegendSettings settings,
const QgsRenderContext context 
)

Entry point called from QgsLegendRenderer to do the rendering in a JSON object.

Parameters
settingsLegend layout configuration
contextRendering context
Since
QGIS 3.8

Definition at line 96 of file qgslayertreemodellegendnode.cpp.

◆ flags()

Qt::ItemFlags QgsLayerTreeModelLegendNode::flags ( ) const
virtual

Returns item flags associated with the item. Default implementation returns Qt::ItemIsEnabled.

Reimplemented in QgsSymbolLegendNode.

Definition at line 51 of file qgslayertreemodellegendnode.cpp.

◆ invalidateMapBasedData()

virtual void QgsLayerTreeModelLegendNode::invalidateMapBasedData ( )
inlinevirtual

Notification from model that information from associated map view has changed.

Default implementation does nothing.

Reimplemented in QgsWmsLegendNode, and QgsSymbolLegendNode.

Definition at line 134 of file qgslayertreemodellegendnode.h.

◆ isEmbeddedInParent()

virtual bool QgsLayerTreeModelLegendNode::isEmbeddedInParent ( ) const
inlinevirtual

Definition at line 84 of file qgslayertreemodellegendnode.h.

◆ isScaleOK()

virtual bool QgsLayerTreeModelLegendNode::isScaleOK ( double  scale) const
inlinevirtual

Reimplemented in QgsSymbolLegendNode.

Definition at line 128 of file qgslayertreemodellegendnode.h.

◆ layerNode()

QgsLayerTreeLayer* QgsLayerTreeModelLegendNode::layerNode ( ) const
inline

Returns pointer to the parent layer node.

Definition at line 70 of file qgslayertreemodellegendnode.h.

◆ model()

QgsLayerTreeModel * QgsLayerTreeModelLegendNode::model ( ) const

Returns pointer to model owning this legend node.

Definition at line 46 of file qgslayertreemodellegendnode.cpp.

◆ setColumnBreak()

virtual void QgsLayerTreeModelLegendNode::setColumnBreak ( bool  breakBeforeNode)
inlinevirtual

Sets whether a forced column break should occur before the node.

See also
columnBreak()
Since
QGIS 3.14

Definition at line 118 of file qgslayertreemodellegendnode.h.

◆ setData()

bool QgsLayerTreeModelLegendNode::setData ( const QVariant &  value,
int  role 
)
virtual

Sets some data associated with the item. Default implementation does nothing and returns false.

Reimplemented in QgsSymbolLegendNode.

Definition at line 56 of file qgslayertreemodellegendnode.cpp.

◆ setEmbeddedInParent()

virtual void QgsLayerTreeModelLegendNode::setEmbeddedInParent ( bool  embedded)
inlinevirtual

Reimplemented in QgsSymbolLegendNode.

Definition at line 85 of file qgslayertreemodellegendnode.h.

◆ setUserLabel()

virtual void QgsLayerTreeModelLegendNode::setUserLabel ( const QString &  userLabel)
inlinevirtual

Reimplemented in QgsSymbolLegendNode.

Definition at line 88 of file qgslayertreemodellegendnode.h.

◆ setUserPatchSize()

void QgsLayerTreeModelLegendNode::setUserPatchSize ( QSizeF  size)
virtual

Sets the user (overridden) size for the legend node.

If either the width or height are non-zero, they will be used when rendering the legend node instead of the default symbol width or height from QgsLegendSettings.

See also
userPatchSize()
Since
QGIS 3.14

Definition at line 71 of file qgslayertreemodellegendnode.cpp.

◆ sizeChanged

void QgsLayerTreeModelLegendNode::sizeChanged ( )
signal

Emitted when the size of this node changes.

Since
QGIS 3.16

◆ userLabel()

virtual QString QgsLayerTreeModelLegendNode::userLabel ( ) const
inlinevirtual

Definition at line 87 of file qgslayertreemodellegendnode.h.

◆ userPatchSize()

QSizeF QgsLayerTreeModelLegendNode::userPatchSize ( ) const
virtual

Returns the user (overridden) size for the legend node.

If either the width or height are non-zero, they will be used when rendering the legend node instead of the default symbol width or height from QgsLegendSettings.

See also
setUserPatchSize()
Since
QGIS 3.14

Definition at line 63 of file qgslayertreemodellegendnode.cpp.

Member Data Documentation

◆ mColumnBreakBeforeNode

bool QgsLayerTreeModelLegendNode::mColumnBreakBeforeNode = false
protected

Definition at line 278 of file qgslayertreemodellegendnode.h.

◆ mEmbeddedInParent

bool QgsLayerTreeModelLegendNode::mEmbeddedInParent
protected

Definition at line 274 of file qgslayertreemodellegendnode.h.

◆ mLayerNode

QgsLayerTreeLayer* QgsLayerTreeModelLegendNode::mLayerNode = nullptr
protected

Definition at line 273 of file qgslayertreemodellegendnode.h.

◆ mPatchShape

QgsLegendPatchShape QgsLayerTreeModelLegendNode::mPatchShape
protected

Definition at line 276 of file qgslayertreemodellegendnode.h.

◆ mUserLabel

QString QgsLayerTreeModelLegendNode::mUserLabel
protected

Definition at line 275 of file qgslayertreemodellegendnode.h.

◆ mUserSize

QSizeF QgsLayerTreeModelLegendNode::mUserSize
protected

Definition at line 277 of file qgslayertreemodellegendnode.h.


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