The abstract base class for all objects that form the layout system. More...

Inheritance diagram for QCPLayoutElement:

Public Types
enum	UpdatePhase { upPreparation , upMargins , upLayout }
	Defines the phases of the update process, that happens just before a replot. More...

enum	SizeConstraintRect { scrInnerRect , scrOuterRect }
	Defines to which rect of a layout element the size constraints that can be set via setMinimumSize and setMaximumSize apply. More...

Public Member Functions
	QCPLayoutElement (QCustomPlot *parentPlot=0)
	Creates an instance of QCPLayoutElement and sets default values.

QCPLayout *	layout () const
	Returns the parent layout of this layout element.

QRect	rect () const
	Returns the inner rect of this layout element.

QRect	outerRect () const
	Returns the outer rect of this layout element.

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)
	Sets the outer rect of this layout element.

void	setMargins (const QMargins &margins)
	Sets the margins of this layout element.

void	setMinimumMargins (const QMargins &margins)
	If setAutoMargins is enabled on some or all margins, this function is used to provide minimum values for those margins.

void	setAutoMargins (QCP::MarginSides sides)
	Sets on which sides the margin shall be calculated automatically.

void	setMinimumSize (const QSize &size)
	Sets the minimum size of this layout element.

void	setMinimumSize (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.Sets the minimum size of this layout element.

void	setMaximumSize (const QSize &size)
	Sets the maximum size of this layout element.

void	setMaximumSize (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.Sets the maximum size of this layout element.

void	setSizeConstraintRect (SizeConstraintRect constraintRect)
	Sets to which rect of a layout element the size constraints apply.

void	setMarginGroup (QCP::MarginSides sides, QCPMarginGroup *group)
	Sets the margin group of the specified margin sides.

virtual void	update (UpdatePhase phase)
	Updates the layout element and sub-elements.

virtual QSize	minimumOuterSizeHint () const
	Returns the suggested minimum size this layout element (the outerRect) may be compressed to, if no manual minimum size is set.

virtual QSize	maximumOuterSizeHint () const
	Returns the suggested maximum size this layout element (the outerRect) may be expanded to, if no manual maximum size is set.

virtual QList< QCPLayoutElement * >	elements (bool recursive) const
	Returns a list of all child elements in this layout element.

virtual double	selectTest (const QPointF &pos, bool onlySelectable, QVariant *details=0) const Q_DECL_OVERRIDE
	Layout elements are sensitive to events inside their outer rect.

Public Member Functions inherited from QCPLayerable
	QCPLayerable (QCustomPlot plot, QString targetLayer=QString(), QCPLayerable parentLayerable=0)
	Creates a new QCPLayerable instance.

bool	visible () const

QCustomPlot *	parentPlot () const

QCPLayerable *	parentLayerable () const
	Returns the parent layerable of this layerable.

QCPLayer *	layer () const

bool	antialiased () const

void	setVisible (bool on)
	Sets the visibility of this layerable object.

Q_SLOT bool	setLayer (QCPLayer *layer)
	Sets the layer of this layerable object.

bool	setLayer (const QString &layerName)
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts. Sets the layer of this layerable object by name.

void	setAntialiased (bool enabled)
	Sets whether this object will be drawn antialiased or not.

virtual double	selectTest (const QPointF &pos, bool onlySelectable, QVariant *details=0) const
	This function is used to decide whether a click hits a layerable object or not.

bool	realVisibility () const
	Returns whether this layerable is visible, taking the visibility of the layerable parent and the visibility of this layerable's layer into account.

Protected Member Functions
virtual int	calculateAutoMargin (QCP::MarginSide side)

virtual void	layoutChanged ()

virtual void	applyDefaultAntialiasingHint (QCPPainter *painter) const Q_DECL_OVERRIDE

virtual void	draw (QCPPainter *painter) Q_DECL_OVERRIDE

virtual void	parentPlotInitialized (QCustomPlot *parentPlot) Q_DECL_OVERRIDE

Protected Member Functions inherited from QCPLayerable
virtual void	parentPlotInitialized (QCustomPlot *parentPlot)

virtual QCP::Interaction	selectionCategory () const

virtual QRect	clipRect () const

virtual void	applyDefaultAntialiasingHint (QCPPainter *painter) const =0

virtual void	draw (QCPPainter *painter)=0

virtual void	selectEvent (QMouseEvent event, bool additive, const QVariant &details, bool selectionStateChanged)

virtual void	deselectEvent (bool *selectionStateChanged)

virtual void	mousePressEvent (QMouseEvent *event, const QVariant &details)
	This event gets called when the user presses a mouse button while the cursor is over the layerable.

virtual void	mouseMoveEvent (QMouseEvent *event, const QPointF &startPos)
	This event gets called when the user moves the mouse while holding a mouse button, after this layerable has become the mouse grabber by accepting the preceding mousePressEvent.

virtual void	mouseReleaseEvent (QMouseEvent *event, const QPointF &startPos)
	This event gets called when the user releases the mouse button, after this layerable has become the mouse grabber by accepting the preceding mousePressEvent.

virtual void	mouseDoubleClickEvent (QMouseEvent *event, const QVariant &details)
	This event gets called when the user presses the mouse button a second time in a double-click, while the cursor is over the layerable.

virtual void	wheelEvent (QWheelEvent *event)
	This event gets called when the user turns the mouse scroll wheel while the cursor is over the layerable.

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
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	QCPLayout

class	QCPMarginGroup

Additional Inherited Members
Signals inherited from QCPLayerable
void	layerChanged (QCPLayer *newLayer)
	This signal is emitted when the layer of this layerable changes, i.e.

Detailed Description

The abstract base class for all objects that form the layout system.

This is an abstract base class. As such, it can't be instantiated directly, rather use one of its subclasses.

A Layout element is a rectangular object which can be placed in layouts. It has an outer rect (QCPLayoutElement::outerRect) and an inner rect (QCPLayoutElement::rect). The difference between outer and inner rect is called its margin. The margin can either be set to automatic or manual (setAutoMargins) on a per-side basis. If a side is set to manual, that margin can be set explicitly with setMargins and will stay fixed at that value. If it's set to automatic, the layout element subclass will control the value itself (via calculateAutoMargin).

Layout elements can be placed in layouts (base class QCPLayout) like QCPLayoutGrid. The top level layout is reachable via QCustomPlot::plotLayout, and is a QCPLayoutGrid. Since QCPLayout itself derives from QCPLayoutElement, layouts can be nested.

Thus in QCustomPlot one can divide layout elements into two categories: The ones that are invisible by themselves, because they don't draw anything. Their only purpose is to manage the position and size of other layout elements. This category of layout elements usually use QCPLayout as base class. Then there is the category of layout elements which actually draw something. For example, QCPAxisRect, QCPLegend and QCPTextElement are of this category. This does not necessarily mean that the latter category can't have child layout elements. QCPLegend for instance, actually derives from QCPLayoutGrid and the individual legend items are child layout elements in the grid layout.

Member Enumeration Documentation

◆ SizeConstraintRect

enum QCPLayoutElement::SizeConstraintRect

Defines to which rect of a layout element the size constraints that can be set via setMinimumSize and setMaximumSize apply.

The outer rect (outerRect) includes the margins (e.g. in the case of a QCPAxisRect the axis labels), whereas the inner rect (rect) does not.

See also: setSizeConstraintRect

Enumerator
scrInnerRect	Minimum/Maximum size constraints apply to inner rect.
scrOuterRect	Minimum/Maximum size constraints apply to outer rect, thus include layout element margins.

◆ UpdatePhase

enum QCPLayoutElement::UpdatePhase

Defines the phases of the update process, that happens just before a replot.

At each phase, update is called with the according UpdatePhase value.

Enumerator
upPreparation	Phase used for any type of preparation that needs to be done before margin calculation and layout.
upMargins	Phase in which the margins are calculated and set.
upLayout	Final phase in which the layout system places the rects of the elements.

Member Function Documentation

◆ applyDefaultAntialiasingHint()

virtual void QCPLayoutElement::applyDefaultAntialiasingHint ( QCPPainter * painter ) const

inlineprotectedvirtual

Implements QCPLayerable.

◆ draw()

virtual void QCPLayoutElement::draw ( QCPPainter * painter )

inlineprotectedvirtual

Implements QCPLayerable.

◆ elements()

QList< QCPLayoutElement * > QCPLayoutElement::elements ( bool recursive ) const

virtual

Returns a list of all child elements in this layout element.

If recursive is true, all sub-child elements are included in the list, too.

Warning: There may be entries with value 0 in the returned list. (For example, QCPLayoutGrid may have empty cells which yield 0 at the respective index.)

Reimplemented in QCPLayout, QCPLayoutGrid, and QCPAxisRect.

◆ maximumOuterSizeHint()

QSize QCPLayoutElement::maximumOuterSizeHint ( ) const

virtual

Returns the suggested maximum size this layout element (the outerRect) may be expanded to, if no manual maximum size is set.

if a maximum size (setMaximumSize) was not set manually, parent layouts use the returned size (usually indirectly through QCPLayout::getFinalMaximumOuterSize) to determine the maximum allowed size of this layout element.

A manual maximum size is considered set if it is smaller than Qt's QWIDGETSIZE_MAX.

The default implementation simply returns QWIDGETSIZE_MAX for both width and height, implying no suggested maximum size. Reimplementations may use their detailed knowledge about the layout element's content to provide size hints.

Reimplemented in QCPLayoutGrid, and QCPTextElement.

◆ minimumOuterSizeHint()

QSize QCPLayoutElement::minimumOuterSizeHint ( ) const

virtual

Returns the suggested minimum size this layout element (the outerRect) may be compressed to, if no manual minimum size is set.

if a minimum size (setMinimumSize) was not set manually, parent layouts use the returned size (usually indirectly through QCPLayout::getFinalMinimumOuterSize) to determine the minimum allowed size of this layout element.

A manual minimum size is considered set if it is non-zero.

The default implementation simply returns the sum of the horizontal margins for the width and the sum of the vertical margins for the height. Reimplementations may use their detailed knowledge about the layout element's content to provide size hints.

Reimplemented in QCPLayoutGrid, QCPPlottableLegendItem, and QCPTextElement.

◆ outerRect()

QRect QCPLayoutElement::outerRect ( ) const

inline

Returns the outer rect of this layout element.

The outer rect is the inner rect expanded by the margins (setMargins, setAutoMargins). The outer rect is used (and set via setOuterRect) by the parent QCPLayout to control the size of this layout element.

See also: rect

◆ parentPlotInitialized()

void QCPLayoutElement::parentPlotInitialized ( QCustomPlot * parentPlot )

protectedvirtual

Reimplemented from QCPLayerable.

◆ rect()

QRect QCPLayoutElement::rect ( ) const

inline

Returns the inner rect of this layout element.

The inner rect is the outer rect (outerRect, setOuterRect) shrinked by the margins (setMargins, setAutoMargins).

In some cases, the area between outer and inner rect is left blank. In other cases the margin area is used to display peripheral graphics while the main content is in the inner rect. This is where automatic margin calculation becomes interesting because it allows the layout element to adapt the margins to the peripheral graphics it wants to draw. For example, QCPAxisRect draws the axis labels and tick labels in the margin area, thus needs to adjust the margins (if setAutoMargins is enabled) according to the space required by the labels of the axes.

See also: outerRect

◆ selectTest()

double QCPLayoutElement::selectTest	(	const QPointF &	pos,
		bool	onlySelectable,
		QVariant *	details = `0`
	)		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 QCPLayerable.

Reimplemented in QCPLayoutInset, QCPAbstractLegendItem, QCPLegend, and QCPTextElement.

◆ setAutoMargins()

void QCPLayoutElement::setAutoMargins ( QCP::MarginSides sides )

Sets on which sides the margin shall be calculated automatically.

If a side is calculated automatically, a minimum margin value may be provided with setMinimumMargins. If a side is set to be controlled manually, the value may be specified with setMargins.

Margin sides that are under automatic control may participate in a QCPMarginGroup (see setMarginGroup), to synchronize (align) it with other layout elements in the plot.

See also: setMinimumMargins, setMargins, QCP::MarginSide

◆ setMarginGroup()

void QCPLayoutElement::setMarginGroup	(	QCP::MarginSides	sides,
		QCPMarginGroup *	group
	)

Sets the margin group of the specified margin sides.

Margin groups allow synchronizing specified margins across layout elements, see the documentation of QCPMarginGroup.

To unset the margin group of sides, set group to 0.

Note that margin groups only work for margin sides that are set to automatic (setAutoMargins).

See also: QCP::MarginSide

◆ setMargins()

void QCPLayoutElement::setMargins ( const QMargins & margins )

Sets the margins of this layout element.

If setAutoMargins is disabled for some or all sides, this function is used to manually set the margin on those sides. Sides that are still set to be handled automatically are ignored and may have any value in margins.

The margin is the distance between the outer rect (controlled by the parent layout via setOuterRect) and the inner rect (which usually contains the main content of this layout element).

See also: setAutoMargins

◆ setMaximumSize() [1/2]

void QCPLayoutElement::setMaximumSize ( const QSize & size )

Sets the maximum size of this layout element.

A parent layout tries to respect the size here by changing row/column sizes in the layout accordingly.

Whether this constraint applies to the inner or the outer rect can be specified with setSizeConstraintRect (see rect and outerRect).

◆ setMaximumSize() [2/2]

void QCPLayoutElement::setMaximumSize	(	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.Sets the maximum size of this layout element.

Whether this constraint applies to the inner or the outer rect can be specified with setSizeConstraintRect (see rect and outerRect).

◆ setMinimumMargins()

void QCPLayoutElement::setMinimumMargins ( const QMargins & margins )

If setAutoMargins is enabled on some or all margins, this function is used to provide minimum values for those margins.

The minimum values are not enforced on margin sides that were set to be under manual control via setAutoMargins.

See also: setAutoMargins

◆ setMinimumSize() [1/2]

void QCPLayoutElement::setMinimumSize ( const QSize & size )

Sets the minimum size of this layout element.

A parent layout tries to respect the size here by changing row/column sizes in the layout accordingly.

If the parent layout size is not sufficient to satisfy all minimum size constraints of its child layout elements, the layout may set a size that is actually smaller than size. QCustomPlot propagates the layout's size constraints to the outside by setting its own minimum QWidget size accordingly, so violations of size should be exceptions.

Whether this constraint applies to the inner or the outer rect can be specified with setSizeConstraintRect (see rect and outerRect).

◆ setMinimumSize() [2/2]

void QCPLayoutElement::setMinimumSize	(	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.Sets the minimum size of this layout element.

Whether this constraint applies to the inner or the outer rect can be specified with setSizeConstraintRect (see rect and outerRect).

◆ setOuterRect()

void QCPLayoutElement::setOuterRect ( const QRect & rect )

Sets the outer rect of this layout element.

If the layout element is inside a layout, the layout sets the position and size of this layout element using this function.

Calling this function externally has no effect, since the layout will overwrite any changes to the outer rect upon the next replot.

The layout element will adapt its inner rect by applying the margins inward to the outer rect.

See also: rect

◆ setSizeConstraintRect()

void QCPLayoutElement::setSizeConstraintRect ( SizeConstraintRect constraintRect )

Sets to which rect of a layout element the size constraints apply.

Size constraints can be set via setMinimumSize and setMaximumSize.

The outer rect (outerRect) includes the margins (e.g. in the case of a QCPAxisRect the axis labels), whereas the inner rect (rect) does not.

See also: setMinimumSize, setMaximumSize

◆ update()

void QCPLayoutElement::update ( UpdatePhase phase )

virtual

Updates the layout element and sub-elements.

This function is automatically called before every replot by the parent layout element. It is called multiple times, once for every UpdatePhase. The phases are run through in the order of the enum values. For details about what happens at the different phases, see the documentation of UpdatePhase.

Layout elements that have child elements should call the update method of their child elements, and pass the current phase unchanged.

The default implementation executes the automatic margin mechanism in the upMargins phase. Subclasses should make sure to call the base class implementation.

Reimplemented in QCPLayout, QCPAxisRect, QCPColorScaleAxisRectPrivate, and QCPColorScale.

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

qcustomplot.h
qcustomplot.cpp

Public Types

Public Member Functions

Protected Member Functions

Protected Attributes

Friends

Additional Inherited Members

Detailed Description

Member Enumeration Documentation

◆ SizeConstraintRect

◆ UpdatePhase

Member Function Documentation

◆ applyDefaultAntialiasingHint()

◆ draw()

◆ elements()

◆ maximumOuterSizeHint()

◆ minimumOuterSizeHint()

◆ outerRect()

◆ parentPlotInitialized()

◆ rect()

◆ selectTest()

◆ setAutoMargins()

◆ setMarginGroup()

◆ setMargins()

◆ setMaximumSize() [1/2]

◆ setMaximumSize() [2/2]

◆ setMinimumMargins()

◆ setMinimumSize() [1/2]

◆ setMinimumSize() [2/2]

◆ setOuterRect()

◆ setSizeConstraintRect()

◆ update()