CopperSpice API  1.9.1
QTextBoundaryFinder Class Reference

Provides a way of finding Unicode text boundaries in a string. More...

Public Typedefs

using BoundaryReasons = QFlags< BoundaryReason >
 

Public Types

enum  BoundaryReason
 
enum  BoundaryType
 

Public Methods

 QTextBoundaryFinder ()
 
 QTextBoundaryFinder (BoundaryType type, const QString &str)
 
 QTextBoundaryFinder (const QTextBoundaryFinder &other)
 
 QTextBoundaryFinder (QTextBoundaryFinder &&other)
 
 ~QTextBoundaryFinder ()
 
BoundaryReasons boundaryReasons () const
 
bool isAtBoundary () const
 
QTextBoundaryFinder & operator= (const QTextBoundaryFinder &other)
 
QTextBoundaryFinder & operator= (QTextBoundaryFinder &&other)
 
int position () const
 
void setPosition (int position)
 
QString string () const
 
void toEnd ()
 
int toNextBoundary ()
 
int toPreviousBoundary ()
 
void toStart ()
 
BoundaryType type () const
 

Detailed Description

The QTextBoundaryFinder class provides a way of finding Unicode text boundaries in a string. This class supports finding boundaries in a string using the rules defined by the Unicode standard. Refer to http://www.unicode.org/reports/tr29 for additional information.

QTextBoundaryFinder can operate on a QString in four possible modes depending on the value of BoundaryType.

Units of Unicode characters that make up what the user thinks of as a character or basic unit of the language are here called Grapheme clusters. The two Unicode characters 'A' + diaeresis do for example form one grapheme cluster as the user thinks of them as one character, yet it is in this case represented by two Unicode code points.

Word boundaries are there to locate the start and end of what a language considers to be a word.

Line break boundaries give possible places where a line break might happen and sentence boundaries will show the beginning and end of whole sentences.

The first position in a string is always a valid boundary and refers to the position before the first character. The last position at the length of the string is also valid and refers to the position after the last character.

See also
setPosition()

Member Typedef Documentation

Member Enumeration Documentation

ConstantValueDescription
QTextBoundaryFinder::NotAtBoundary 0x00 Not at a boundary position
QTextBoundaryFinder::BreakOpportunity 0x1f At a break opportunity position, might also be an item boundary (either StartOfItem, EndOfItem, or combination of both), a mandatory line break, or a soft hyphen
QTextBoundaryFinder::StartOfItem 0x20 At the start of a grapheme, a word, a sentence, or a line
QTextBoundaryFinder::EndOfItem 0x30 At the end of a grapheme, a word, a sentence, or a line
QTextBoundaryFinder::MandatoryBreak 0x80 At the end of line, occurs for a Line boundary type only
QTextBoundaryFinder::SoftHyphen 0x100 At the soft hyphen, occurs for a Line boundary type only
ConstantValueDescription
QTextBoundaryFinder::Grapheme 0 Finds a grapheme which is the smallest boundary, includes letters, punctuation marks, numerals, etc
QTextBoundaryFinder::Word 1 Finds a word
QTextBoundaryFinder::Line 2 Finds possible positions for breaking the text into multiple lines
QTextBoundaryFinder::Sentence3 Finds sentence boundaries, include periods, question marks, etc

Constructor & Destructor Documentation

QTextBoundaryFinder::QTextBoundaryFinder ( )

Constructs an empty QTextBoundaryFinder object.

QTextBoundaryFinder::QTextBoundaryFinder ( const QTextBoundaryFinder &  other)

Copy constructs a new QTextBoundaryFinder from other.

QTextBoundaryFinder::QTextBoundaryFinder ( QTextBoundaryFinder &&  other)

Move constructs a new QTextBoundaryFinder from other.

QTextBoundaryFinder::QTextBoundaryFinder ( BoundaryType  type,
const QString str 
)

Creates a QTextBoundaryFinder object of type operating on string.

QTextBoundaryFinder::~QTextBoundaryFinder ( )

Destructs the QTextBoundaryFinder object.

Method Documentation

BoundaryReasons QTextBoundaryFinder::boundaryReasons ( ) const

Returns the reasons for the boundary finder to have chosen the current position as a boundary.

bool QTextBoundaryFinder::isAtBoundary ( ) const

Returns true if the object's position() is currently at a valid text boundary.

QTextBoundaryFinder & QTextBoundaryFinder::operator= ( const QTextBoundaryFinder &  other)

Copy assigns from other and returns a reference to this object.

QTextBoundaryFinder & QTextBoundaryFinder::operator= ( QTextBoundaryFinder &&  other)

Move assigns from other and returns a reference to this object.

int QTextBoundaryFinder::position ( ) const

Returns the current position of the QTextBoundaryFinder. The range is from 0 (the beginning of the string) to the length of the string inclusive.

See also
setPosition()
void QTextBoundaryFinder::setPosition ( int  position)

Sets the current position of the QTextBoundaryFinder to position. If position is out of bounds, it will be bound to only valid positions. In this case, valid positions are from 0 to the length of the string inclusive.

See also
position()
QString QTextBoundaryFinder::string ( ) const

Returns the string the QTextBoundaryFinder object operates on.

void QTextBoundaryFinder::toEnd ( )

Moves the finder to the end of the string. This is equivalent to setPosition(string.length()).

See also
setPosition(), position()
int QTextBoundaryFinder::toNextBoundary ( )

Moves the QTextBoundaryFinder to the next boundary position and returns that position.

Returns -1 if there is no next boundary.

int QTextBoundaryFinder::toPreviousBoundary ( )

Moves the QTextBoundaryFinder to the previous boundary position and returns that position. Returns -1 if there is no previous boundary.

void QTextBoundaryFinder::toStart ( )

Moves the finder to the start of the string. Equivalent to setPosition(0).

See also
setPosition(), position()
BoundaryType QTextBoundaryFinder::type ( ) const
inline

Returns the type of the QTextBoundaryFinder.