The QTextLine class represents a line of text inside a QTextLayout. More...

Public Types
enum	CursorPosition

enum	Edge

Public Methods
	QTextLine ()

qreal	ascent () const

qreal	cursorToX (int *cursorPos, Edge edge=Leading) const

qreal	cursorToX (int cursorPos, Edge edge=Leading) const

qreal	descent () const

void	draw (QPainter painter, const QPointF &point, const QTextLayout::FormatRange selection=nullptr) const

QList< QGlyphRun >	glyphRuns (int from=-1, int length=-1) const

qreal	height () const

qreal	horizontalAdvance () const

bool	isValid () const

qreal	leading () const

bool	leadingIncluded () const

int	lineNumber () const

QRectF	naturalTextRect () const

qreal	naturalTextWidth () const

QPointF	position () const

QRectF	rect () const

void	setLeadingIncluded (bool included)

void	setLineWidth (qreal width)

void	setNumColumns (int columns, std::optional< qreal > alignmentWidth=std::optional< qreal >())

void	setPosition (const QPointF &point)

int	textLength () const

int	textStart () const

qreal	width () const

qreal	x () const

int	xToCursor (qreal x, CursorPosition cursorPos=CursorBetweenCharacters) const

qreal	y () const

Friends
class	QTextFragment

class	QTextLayout

Detailed Description

The QTextLine class represents a line of text inside a QTextLayout.

A text line is usually created by QTextLayout::createLine().

After being created, the line can be filled using the setLineWidth() or setNumColumns() functions. A line has a number of attributes including the rectangle it occupies, rect(), its coordinates, x() and y(), its textLength(), width() and naturalTextWidth(), and its ascent() and decent() relative to the text. The position of the cursor in terms of the line is available from cursorToX() and its inverse from xToCursor(). A line can be moved with setPosition().

See also: descent(), height()

Member Enumeration Documentation

enum QTextLine::CursorPosition

Constant	Value
`QTextLine::CursorBetweenCharacters`	`0`
`QTextLine::CursorOnCharacter`	`1`

enum QTextLine::Edge

Constant	Value
`QTextLine::Leading`	`0`
`QTextLine::Trailing`	`1`

Constructor & Destructor Documentation

QTextLine::QTextLine ( )

inline

Creates an invalid line.

Method Documentation

qreal QTextLine::ascent ( ) const

Returns the line's ascent.

See also: descent(), height()

qreal QTextLine::cursorToX	(	int *	cursorPos,
		Edge	edge = `Leading`
	)		const

Converts the cursor position cursorPos to the corresponding X position inside the line, taking account of the edge.

If cursorPos is not a valid cursor position then the nearest valid cursor position will be used. The cursorPos will be modified to point to this valid cursor position.

See also: xToCursor()

qreal QTextLine::cursorToX	(	int	cursorPos,
		Edge	edge = `Leading`
	)		const

inline

Converts the cursor position cursorPos to the corresponding X position inside the line, taking account of the edge.

qreal QTextLine::descent ( ) const

Returns the line's descent.

See also: ascent(), height()

void QTextLine::draw	(	QPainter *	painter,
		const QPointF &	point,
		const QTextLayout::FormatRange *	selection = `nullptr`
	)		const

Draws a line on the given painter at the specified point. The selection is reserved for internal use.

QList< QGlyphRun > QTextLine::glyphRuns	(	int	from = `-1`,
		int	length = `-1`
	)		const

Returns the glyph indexes and positions for all glyphs in this QTextLine for characters in the range defined by from and length. The from index is relative to the beginning of the text in the containing QTextLayout, and the range must be within the range of QTextLine as given by functions textStart() and textLength().

If from is negative, it will default to textStart(), and if length is negative it will default to the return value of textLength().

See also: QTextLayout::glyphRuns()

qreal QTextLine::height ( ) const

Returns the line's height. This is equal to ascent() + descent() + 1 if leading is not included. If leading is included, this equals to ascent() + descent() + leading() + 1.

See also: ascent(), descent(), leading(), setLeadingIncluded()

qreal QTextLine::horizontalAdvance ( ) const

Returns the horizontal advance of the text. The advance of the text is the distance from its position to the next position at which text would naturally be drawn. By adding the advance to the position of the text line and using this as the position of a second text line, you will be able to position the two lines side-by-side without gaps in-between.

bool QTextLine::isValid ( ) const

inline

Returns true if this text line is valid, otherwise returns false.

qreal QTextLine::leading ( ) const

Returns the line's leading.

See also: ascent(), descent(), height()

bool QTextLine::leadingIncluded ( ) const

Returns true if positive leading is included into the line's height, otherwise returns false.

By default, leading is not included.

See also: setLeadingIncluded()

int QTextLine::lineNumber ( ) const

inline

Returns the position of the line in the text engine.

QRectF QTextLine::naturalTextRect ( ) const

Returns the rectangle covered by the line.

qreal QTextLine::naturalTextWidth ( ) const

Returns the width of the line that is occupied by text. This is always <= to width() and is the minimum width that could be used by layout() without changing the line break position.

QPointF QTextLine::position ( ) const

Returns the line's position relative to the text layout's position.

See also: setPosition()

QRectF QTextLine::rect ( ) const

Returns the line's bounding rectangle.

See also: x(), y(), textLength(), width()

void QTextLine::setLeadingIncluded ( bool included )

Includes positive leading into the line's height if included is true, otherwise does not include leading. By default leading is not included.

Negative leading is ignored and it must be handled in the code using the text lines by letting the lines overlap.

See also: leadingIncluded()

void QTextLine::setLineWidth ( qreal width )

Lays out the line with the given width. The line is filled from its starting position with as many characters as will fit into the line. In case the text can not be split at the end of the line, it will be filled with additional characters to the next whitespace or end of the text.

void QTextLine::setNumColumns	(	int	columns,
		std::optional< qreal >	alignmentWidth = `std::optional<qreal>()`
	)

Lays out the line by filling from the starting position using the number of characters specified by columns.

In case the text can not be split until numColumns characters, the line will be filled with as many characters to the next whitespace or end of the text. The given alignmentWidth is used as reference width for alignment.

void QTextLine::setPosition ( const QPointF & point )

Moves the line to position point.