Manages a legend inside a QCustomPlot. More...

Inheritance diagram for QCPLegend:

Public Types
enum	SelectablePart { spNone = 0x000 , spLegendBox = 0x001 , spItems = 0x002 }
Public Types inherited from QCPLayoutGrid
enum	FillOrder { foRowsFirst , foColumnsFirst }
Public Types inherited from QCPLayoutElement
enum	UpdatePhase { upPreparation , upMargins , upLayout }
enum	SizeConstraintRect { scrInnerRect , scrOuterRect }

Signals
void	selectionChanged (QCPLegend::SelectableParts parts)
void	selectableChanged (QCPLegend::SelectableParts parts)
Signals inherited from QCPLayerable
void	layerChanged (QCPLayer *newLayer)

Public Member Functions
	QCPLegend ()
QPen	borderPen () const
QBrush	brush () const
QFont	font () const
QColor	textColor () const
QSize	iconSize () const
int	iconTextPadding () const
QPen	iconBorderPen () const
SelectableParts	selectableParts () const
SelectableParts	selectedParts () const
QPen	selectedBorderPen () const
QPen	selectedIconBorderPen () const
QBrush	selectedBrush () const
QFont	selectedFont () const
QColor	selectedTextColor () const
void	setBorderPen (const QPen &pen)
void	setBrush (const QBrush &brush)
void	setFont (const QFont &font)
void	setTextColor (const QColor &color)
void	setIconSize (const QSize &size)
void	setIconSize (int width, int height)
void	setIconTextPadding (int padding)
void	setIconBorderPen (const QPen &pen)
Q_SLOT void	setSelectableParts (const SelectableParts &selectableParts)
Q_SLOT void	setSelectedParts (const SelectableParts &selectedParts)
void	setSelectedBorderPen (const QPen &pen)
void	setSelectedIconBorderPen (const QPen &pen)
void	setSelectedBrush (const QBrush &brush)
void	setSelectedFont (const QFont &font)
void	setSelectedTextColor (const QColor &color)
virtual double	selectTest (const QPointF &pos, bool onlySelectable, QVariant *details=nullptr) const Q_DECL_OVERRIDE
QCPAbstractLegendItem *	item (int index) const
QCPPlottableLegendItem *	itemWithPlottable (const QCPAbstractPlottable *plottable) const
int	itemCount () const
bool	hasItem (QCPAbstractLegendItem *item) const
bool	hasItemWithPlottable (const QCPAbstractPlottable *plottable) const
bool	addItem (QCPAbstractLegendItem *item)
bool	removeItem (int index)
bool	removeItem (QCPAbstractLegendItem *item)
void	clearItems ()
QList< QCPAbstractLegendItem * >	selectedItems () const
Public Member Functions inherited from QCPLayoutGrid
	QCPLayoutGrid ()
int	rowCount () const
int	columnCount () const
QList< double >	columnStretchFactors () const
QList< double >	rowStretchFactors () const
int	columnSpacing () const
int	rowSpacing () const
int	wrap () const
FillOrder	fillOrder () const
void	setColumnStretchFactor (int column, double factor)
void	setColumnStretchFactors (const QList< double > &factors)
void	setRowStretchFactor (int row, double factor)
void	setRowStretchFactors (const QList< double > &factors)
void	setColumnSpacing (int pixels)
void	setRowSpacing (int pixels)
void	setWrap (int count)
void	setFillOrder (FillOrder order, bool rearrange=true)
virtual void	updateLayout () Q_DECL_OVERRIDE
virtual int	elementCount () const Q_DECL_OVERRIDE
virtual QCPLayoutElement *	elementAt (int index) const Q_DECL_OVERRIDE
virtual QCPLayoutElement *	takeAt (int index) Q_DECL_OVERRIDE
virtual bool	take (QCPLayoutElement *element) Q_DECL_OVERRIDE
virtual QList< QCPLayoutElement * >	elements (bool recursive) const Q_DECL_OVERRIDE
virtual void	simplify () Q_DECL_OVERRIDE
virtual QSize	minimumOuterSizeHint () const Q_DECL_OVERRIDE
virtual QSize	maximumOuterSizeHint () const Q_DECL_OVERRIDE
QCPLayoutElement *	element (int row, int column) const
bool	addElement (int row, int column, QCPLayoutElement *element)
bool	addElement (QCPLayoutElement *element)
bool	hasElement (int row, int column)
void	expandTo (int newRowCount, int newColumnCount)
void	insertRow (int newIndex)
void	insertColumn (int newIndex)
int	rowColToIndex (int row, int column) const
void	indexToRowCol (int index, int &row, int &column) const
Public Member Functions inherited from QCPLayout
	QCPLayout ()
virtual void	update (UpdatePhase phase) Q_DECL_OVERRIDE
bool	removeAt (int index)
bool	remove (QCPLayoutElement *element)
void	clear ()
Public Member Functions inherited from QCPLayoutElement
	QCPLayoutElement (QCustomPlot *parentPlot=nullptr)
QCPLayout *	layout () const
QRect	rect () const
QRect	outerRect () const
QMargins	margins () const
QMargins	minimumMargins () const
QCP::MarginSides	autoMargins () const
QSize	minimumSize () const
QSize	maximumSize () const
SizeConstraintRect	sizeConstraintRect () const
QCPMarginGroup *	marginGroup (QCP::MarginSide side) const
QHash< QCP::MarginSide, QCPMarginGroup * >	marginGroups () const
void	setOuterRect (const QRect &rect)
void	setMargins (const QMargins &margins)
void	setMinimumMargins (const QMargins &margins)
void	setAutoMargins (QCP::MarginSides sides)
void	setMinimumSize (const QSize &size)
void	setMinimumSize (int width, int height)
void	setMaximumSize (const QSize &size)
void	setMaximumSize (int width, int height)
void	setSizeConstraintRect (SizeConstraintRect constraintRect)
void	setMarginGroup (QCP::MarginSides sides, QCPMarginGroup *group)
Public Member Functions inherited from QCPLayerable
	QCPLayerable (QCustomPlot plot, QString targetLayer=QString(), QCPLayerable parentLayerable=nullptr)
bool	visible () const
QCustomPlot *	parentPlot () const
QCPLayerable *	parentLayerable () const
QCPLayer *	layer () const
bool	antialiased () const
void	setVisible (bool on)
Q_SLOT bool	setLayer (QCPLayer *layer)
bool	setLayer (const QString &layerName)
void	setAntialiased (bool enabled)
bool	realVisibility () const

Protected Member Functions
virtual void	parentPlotInitialized (QCustomPlot *parentPlot) Q_DECL_OVERRIDE
virtual QCP::Interaction	selectionCategory () const Q_DECL_OVERRIDE
virtual void	applyDefaultAntialiasingHint (QCPPainter *painter) const Q_DECL_OVERRIDE
virtual void	draw (QCPPainter *painter) Q_DECL_OVERRIDE
virtual void	selectEvent (QMouseEvent event, bool additive, const QVariant &details, bool selectionStateChanged) Q_DECL_OVERRIDE
virtual void	deselectEvent (bool *selectionStateChanged) Q_DECL_OVERRIDE
QPen	getBorderPen () const
QBrush	getBrush () const
Protected Member Functions inherited from QCPLayoutGrid
void	getMinimumRowColSizes (QVector< int > minColWidths, QVector< int > minRowHeights) const
void	getMaximumRowColSizes (QVector< int > maxColWidths, QVector< int > maxRowHeights) const
Protected Member Functions inherited from QCPLayout
void	sizeConstraintsChanged () const
void	adoptElement (QCPLayoutElement *el)
void	releaseElement (QCPLayoutElement *el)
QVector< int >	getSectionSizes (QVector< int > maxSizes, QVector< int > minSizes, QVector< double > stretchFactors, int totalSize) const
Protected Member Functions inherited from QCPLayoutElement
virtual int	calculateAutoMargin (QCP::MarginSide side)
virtual void	layoutChanged ()
Protected Member Functions inherited from QCPLayerable
virtual QRect	clipRect () const
virtual void	mousePressEvent (QMouseEvent *event, const QVariant &details)
virtual void	mouseMoveEvent (QMouseEvent *event, const QPointF &startPos)
virtual void	mouseReleaseEvent (QMouseEvent *event, const QPointF &startPos)
virtual void	mouseDoubleClickEvent (QMouseEvent *event, const QVariant &details)
virtual void	wheelEvent (QWheelEvent *event)
void	initializeParentPlot (QCustomPlot *parentPlot)
void	setParentLayerable (QCPLayerable *parentLayerable)
bool	moveToLayer (QCPLayer *layer, bool prepend)
void	applyAntialiasingHint (QCPPainter *painter, bool localAntialiased, QCP::AntialiasedElement overrideElement) const

Protected Attributes
QPen	mBorderPen
QPen	mIconBorderPen
QBrush	mBrush
QFont	mFont
QColor	mTextColor
QSize	mIconSize
int	mIconTextPadding
SelectableParts	mSelectedParts
SelectableParts	mSelectableParts
QPen	mSelectedBorderPen
QPen	mSelectedIconBorderPen
QBrush	mSelectedBrush
QFont	mSelectedFont
QColor	mSelectedTextColor
Protected Attributes inherited from QCPLayoutGrid
QList< QList< QCPLayoutElement * > >	mElements
QList< double >	mColumnStretchFactors
QList< double >	mRowStretchFactors
int	mColumnSpacing
int	mRowSpacing
int	mWrap
FillOrder	mFillOrder
Protected Attributes inherited from QCPLayoutElement
QCPLayout *	mParentLayout
QSize	mMinimumSize
QSize	mMaximumSize
SizeConstraintRect	mSizeConstraintRect
QRect	mRect
QRect	mOuterRect
QMargins	mMargins
QMargins	mMinimumMargins
QCP::MarginSides	mAutoMargins
QHash< QCP::MarginSide, QCPMarginGroup * >	mMarginGroups
Protected Attributes inherited from QCPLayerable
bool	mVisible
QCustomPlot *	mParentPlot
QPointer< QCPLayerable >	mParentLayerable
QCPLayer *	mLayer
bool	mAntialiased

Friends
class	QCustomPlot
class	QCPAbstractLegendItem

Additional Inherited Members
Static Protected Member Functions inherited from QCPLayout
static QSize	getFinalMinimumOuterSize (const QCPLayoutElement *el)
static QSize	getFinalMaximumOuterSize (const QCPLayoutElement *el)

Detailed Description

Manages a legend inside a QCustomPlot.

A legend is a small box somewhere in the plot which lists plottables with their name and icon.

A legend is populated with legend items by calling QCPAbstractPlottable::addToLegend on the plottable, for which a legend item shall be created. In the case of the main legend (QCustomPlot::legend), simply adding plottables to the plot while QCustomPlot::setAutoAddPlottableToLegend is set to true (the default) creates corresponding legend items. The legend item associated with a certain plottable can be removed with QCPAbstractPlottable::removeFromLegend. However, QCPLegend also offers an interface to add and manipulate legend items directly: item, itemWithPlottable, itemCount, addItem, removeItem, etc.

Since QCPLegend derives from QCPLayoutGrid, it can be placed in any position a QCPLayoutElement may be positioned. The legend items are themselves QCPLayoutElements which are placed in the grid layout of the legend. QCPLegend only adds an interface specialized for handling child elements of type QCPAbstractLegendItem, as mentioned above. In principle, any other layout elements may also be added to a legend via the normal QCPLayoutGrid interface. See the special page about The Layout System for examples on how to add other elements to the legend and move it outside the axis rect.

Use the methods setFillOrder and setWrap inherited from QCPLayoutGrid to control in which order (column first or row first) the legend is filled up when calling addItem, and at which column or row wrapping occurs. The default fill order for legends is foRowsFirst.

By default, every QCustomPlot has one legend (QCustomPlot::legend) which is placed in the inset layout of the main axis rect (QCPAxisRect::insetLayout). To move the legend to another position inside the axis rect, use the methods of the QCPLayoutInset. To move the legend outside of the axis rect, place it anywhere else with the QCPLayout/ QCPLayoutElement interface.

Member Enumeration Documentation

◆ SelectablePart

enum QCPLegend::SelectablePart

Defines the selectable parts of a legend

See also: setSelectedParts, setSelectableParts

Enumerator
spNone	0x000 None
spLegendBox	0x001 The legend box (frame)
spItems	0x002 Legend items individually (see selectedItems)

Constructor & Destructor Documentation

◆ QCPLegend()

QCPLegend::QCPLegend ( )

explicit

Constructs a new QCPLegend instance with default values.

Note that by default, QCustomPlot already contains a legend ready to be used as QCustomPlot::legend

Member Function Documentation

◆ addItem()

bool QCPLegend::addItem ( QCPAbstractLegendItem * item )

Adds item to the legend, if it's not present already. The element is arranged according to the current fill order (setFillOrder) and wrapping (setWrap).

Returns true on sucess, i.e. if the item wasn't in the list already and has been successfuly added.

The legend takes ownership of the item.

See also: removeItem, item, hasItem

◆ applyDefaultAntialiasingHint()

void QCPLegend::applyDefaultAntialiasingHint ( QCPPainter * painter ) const

protectedvirtual

Reimplemented from QCPLayoutElement.

◆ clearItems()

void QCPLegend::clearItems ( )

Removes all items from the legend.

◆ deselectEvent()

void QCPLegend::deselectEvent ( bool * selectionStateChanged )

protectedvirtual

Reimplemented from QCPLayerable.

◆ draw()

void QCPLegend::draw ( QCPPainter * painter )

protectedvirtual

Reimplemented from QCPLayoutElement.

◆ hasItem()

bool QCPLegend::hasItem ( QCPAbstractLegendItem * item ) const

Returns whether the legend contains item.

See also: hasItemWithPlottable

◆ hasItemWithPlottable()

bool QCPLegend::hasItemWithPlottable ( const QCPAbstractPlottable * plottable ) const

Returns whether the legend contains a QCPPlottableLegendItem which is associated with plottable (e.g. a QCPGraph*). If such an item isn't in the legend, returns false.

See also: itemWithPlottable

◆ item()

QCPAbstractLegendItem * QCPLegend::item ( int index ) const

Returns the item with index i. If non-legend items were added to the legend, and the element at the specified cell index is not a QCPAbstractLegendItem, returns nullptr.

Note that the linear index depends on the current fill order (setFillOrder).

See also: itemCount, addItem, itemWithPlottable

◆ itemCount()

int QCPLegend::itemCount ( ) const

Returns the number of items currently in the legend. It is identical to the base class QCPLayoutGrid::elementCount(), and unlike the other "item" interface methods of QCPLegend, doesn't only address elements which can be cast to QCPAbstractLegendItem.

Note that if empty cells are in the legend (e.g. by calling methods of the QCPLayoutGrid base class which allows creating empty cells), they are included in the returned count.

See also: item

◆ itemWithPlottable()

QCPPlottableLegendItem * QCPLegend::itemWithPlottable ( const QCPAbstractPlottable * plottable ) const

Returns the QCPPlottableLegendItem which is associated with plottable (e.g. a QCPGraph*). If such an item isn't in the legend, returns nullptr.

See also: hasItemWithPlottable

◆ parentPlotInitialized()

void QCPLegend::parentPlotInitialized ( QCustomPlot * parentPlot )

protectedvirtual

Reimplemented from QCPLayoutElement.

◆ removeItem() [1/2]

bool QCPLegend::removeItem ( int index )

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

Removes the item with the specified index from the legend and deletes it.

After successful removal, the legend is reordered according to the current fill order (setFillOrder) and wrapping (setWrap), so no empty cell remains where the removed item was. If you don't want this, rather use the raw element interface of QCPLayoutGrid.

Returns true, if successful. Unlike QCPLayoutGrid::removeAt, this method only removes elements derived from QCPAbstractLegendItem.

See also: itemCount, clearItems

◆ removeItem() [2/2]

bool QCPLegend::removeItem ( QCPAbstractLegendItem * item )

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

Removes item from the legend and deletes it.

After successful removal, the legend is reordered according to the current fill order (setFillOrder) and wrapping (setWrap), so no empty cell remains where the removed item was. If you don't want this, rather use the raw element interface of QCPLayoutGrid.

Returns true, if successful.

See also: clearItems

◆ selectedItems()

QList< QCPAbstractLegendItem * > QCPLegend::selectedItems ( ) const

Returns the legend items that are currently selected. If no items are selected, the list is empty.

See also: QCPAbstractLegendItem::setSelected, setSelectable

◆ selectEvent()

void QCPLegend::selectEvent	(	QMouseEvent *	event,
		bool	additive,
		const QVariant &	details,
		bool *	selectionStateChanged )

protectedvirtual

Reimplemented from QCPLayerable.

◆ selectionCategory()

QCP::Interaction QCPLegend::selectionCategory ( ) const

protectedvirtual

Reimplemented from QCPLayerable.

◆ selectionChanged

void QCPLegend::selectionChanged ( QCPLegend::SelectableParts selection )

signal

This signal is emitted when the selection state of this legend has changed.

See also: setSelectedParts, setSelectableParts

◆ selectTest()

double QCPLegend::selectTest	(	const QPointF &	pos,
		bool	onlySelectable,
		QVariant *	details = nullptr ) const

virtual

Layout elements are sensitive to events inside their outer rect. If pos is within the outer rect, this method returns a value corresponding to 0.99 times the parent plot's selection tolerance. However, layout elements are not selectable by default. So if onlySelectable is true, -1.0 is returned.

See QCPLayerable::selectTest for a general explanation of this virtual method.

QCPLayoutElement subclasses may reimplement this method to provide more specific selection test behaviour.

Reimplemented from QCPLayoutElement.

◆ setBorderPen()

void QCPLegend::setBorderPen ( const QPen & pen )

Sets the pen, the border of the entire legend is drawn with.

◆ setBrush()

void QCPLegend::setBrush ( const QBrush & brush )

Sets the brush of the legend background.

◆ setFont()

void QCPLegend::setFont ( const QFont & font )

Sets the default font of legend text. Legend items that draw text (e.g. the name of a graph) will use this font by default. However, a different font can be specified on a per-item-basis by accessing the specific legend item.

This function will also set font on all already existing legend items.

See also: QCPAbstractLegendItem::setFont

◆ setIconBorderPen()

void QCPLegend::setIconBorderPen ( const QPen & pen )

Sets the pen used to draw a border around each legend icon. Legend items that draw an icon (e.g. a visual representation of the graph) will use this pen by default.

If no border is wanted, set this to Qt::NoPen.

◆ setIconSize() [1/2]

void QCPLegend::setIconSize ( const QSize & size )

Sets the size of legend icons. Legend items that draw an icon (e.g. a visual representation of the graph) will use this size by default.

◆ setIconSize() [2/2]

void QCPLegend::setIconSize	(	int	width,
		int	height )

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

◆ setIconTextPadding()

void QCPLegend::setIconTextPadding ( int padding )

Sets the horizontal space in pixels between the legend icon and the text next to it. Legend items that draw an icon (e.g. a visual representation of the graph) and text (e.g. the name of the graph) will use this space by default.

◆ setSelectableParts()

void QCPLegend::setSelectableParts ( const SelectableParts & selectable )

Sets whether the user can (de-)select the parts in selectable by clicking on the QCustomPlot surface. (When QCustomPlot::setInteractions contains QCP::iSelectLegend.)

However, even when selectable is set to a value not allowing the selection of a specific part, it is still possible to set the selection of this part manually, by calling setSelectedParts directly.

See also: SelectablePart, setSelectedParts

◆ setSelectedBorderPen()

void QCPLegend::setSelectedBorderPen ( const QPen & pen )

When the legend box is selected, this pen is used to draw the border instead of the normal pen set via setBorderPen.

See also: setSelectedParts, setSelectableParts, setSelectedBrush

◆ setSelectedBrush()

void QCPLegend::setSelectedBrush ( const QBrush & brush )

When the legend box is selected, this brush is used to draw the legend background instead of the normal brush set via setBrush.

See also: setSelectedParts, setSelectableParts, setSelectedBorderPen

◆ setSelectedFont()

void QCPLegend::setSelectedFont ( const QFont & font )

Sets the default font that is used by legend items when they are selected.

This function will also set font on all already existing legend items.

See also: setFont, QCPAbstractLegendItem::setSelectedFont

◆ setSelectedIconBorderPen()

void QCPLegend::setSelectedIconBorderPen ( const QPen & pen )

Sets the pen legend items will use to draw their icon borders, when they are selected.

See also: setSelectedParts, setSelectableParts, setSelectedFont

◆ setSelectedParts()

void QCPLegend::setSelectedParts ( const SelectableParts & selected )

Sets the selected state of the respective legend parts described by SelectablePart. When a part is selected, it uses a different pen/font and brush. If some legend items are selected and selected doesn't contain spItems, those items become deselected.

The entire selection mechanism is handled automatically when QCustomPlot::setInteractions contains iSelectLegend. You only need to call this function when you wish to change the selection state manually.

This function can change the selection state of a part even when setSelectableParts was set to a value that actually excludes the part.

emits the selectionChanged signal when selected is different from the previous selection state.

Note that it doesn't make sense to set the selected state spItems here when it wasn't set before, because there's no way to specify which exact items to newly select. Do this by calling QCPAbstractLegendItem::setSelected directly on the legend item you wish to select.

See also: SelectablePart, setSelectableParts, selectTest, setSelectedBorderPen, setSelectedIconBorderPen, setSelectedBrush, setSelectedFont

◆ setSelectedTextColor()

void QCPLegend::setSelectedTextColor ( const QColor & color )

Sets the default text color that is used by legend items when they are selected.

This function will also set color on all already existing legend items.

See also: setTextColor, QCPAbstractLegendItem::setSelectedTextColor

◆ setTextColor()

void QCPLegend::setTextColor ( const QColor & color )

Sets the default color of legend text. Legend items that draw text (e.g. the name of a graph) will use this color by default. However, a different colors can be specified on a per-item-basis by accessing the specific legend item.

This function will also set color on all already existing legend items.

See also: QCPAbstractLegendItem::setTextColor

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

qcustomplot.h
qcustomplot.cpp

Public Types

Signals

Public Member Functions

Protected Member Functions

Protected Attributes

Friends

Additional Inherited Members

Detailed Description

Member Enumeration Documentation

◆ SelectablePart

Constructor & Destructor Documentation

◆ QCPLegend()

Member Function Documentation

◆ addItem()

◆ applyDefaultAntialiasingHint()

◆ clearItems()

◆ deselectEvent()

◆ draw()

◆ hasItem()

◆ hasItemWithPlottable()

◆ item()

◆ itemCount()

◆ itemWithPlottable()

◆ parentPlotInitialized()

◆ removeItem() [1/2]

◆ removeItem() [2/2]

◆ selectedItems()

◆ selectEvent()

◆ selectionCategory()

◆ selectionChanged

◆ selectTest()

◆ setBorderPen()

◆ setBrush()

◆ setFont()

◆ setIconBorderPen()

◆ setIconSize() [1/2]

◆ setIconSize() [2/2]

◆ setIconTextPadding()

◆ setSelectableParts()

◆ setSelectedBorderPen()

◆ setSelectedBrush()

◆ setSelectedFont()

◆ setSelectedIconBorderPen()

◆ setSelectedParts()

◆ setSelectedTextColor()

◆ setTextColor()