QTextLine 类表示一行文本在 QTextLayout . 更多...
| 头： | #include <QTextLine> |
| CMake: |
find_package(Qt6 COMPONENTS Gui REQUIRED)
target_link_libraries(mytarget PRIVATE Qt6::Gui) |
| qmake: | QT += gui |
注意： 此类的所有函数 可重入 .
| enum | CursorPosition { CursorBetweenCharacters, CursorOnCharacter } |
| enum | Edge { Leading, Trailing } |
| QTextLine () | |
| qreal | ascent () const |
| qreal | cursorToX (int * cursorPos , QTextLine::Edge edge = Leading) const |
| qreal | cursorToX (int cursorPos , QTextLine::Edge edge = Leading) const |
| qreal | descent () const |
| void | draw (QPainter * painter , const QPointF & position ) 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 numColumns ) |
| void | setNumColumns (int numColumns , qreal alignmentWidth ) |
| void | setPosition (const QPointF & pos ) |
| int | textLength () const |
| int | textStart () const |
| qreal | width () const |
| qreal | x () const |
| int | xToCursor (qreal x , QTextLine::CursorPosition cpos = CursorBetweenCharacters) const |
| qreal | y () const |
A text line is usually created by QTextLayout::createLine ().
After being created, the line can be filled using the setLineWidth () 或 setNumColumns () functions. A line has a number of attributes including the rectangle it occupies, rect (), its coordinates, x () 和 y ()，其 textLength (), width () 和 naturalTextWidth ()，及其 ascent () 和 descent () 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 ().
| 常量 | 值 |
|---|---|
QTextLine::CursorBetweenCharacters
|
0
|
QTextLine::CursorOnCharacter
|
1
|
| 常量 | 值 |
|---|---|
QTextLine::Leading
|
0
|
QTextLine::Trailing
|
1
|
Creates an invalid line.
Returns the line's ascent.
Converts the cursor position cursorPos to the corresponding x position inside the line, taking account of the edge .
若 cursorPos is not a valid cursor position, the nearest valid cursor position will be used instead, and cursorPos will be modified to point to this valid cursor position.
另请参阅 xToCursor ().
这是重载函数。
Returns the line's descent.
Draws a line on the given painter at the specified position .
[since 5.0]
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 。 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 () 和 textLength ().
若 from is negative, it will default to textStart (), and if length is negative it will default to the return value of textLength ().
该函数在 Qt 5.0 引入。
另请参阅 QTextLayout::glyphRuns ().
Returns the line's height. This is equal to ascent () + descent () if leading is not included. If leading is included, this equals to ascent () + descent () + leading ().
另请参阅 ascent (), descent (), leading ()，和 setLeadingIncluded ().
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.
返回
true
if this text line is valid; otherwise returns
false
.
Returns the line's leading.
另请参阅 ascent (), descent ()，和 height ().
返回
true
if positive leading is included into the line's height; otherwise returns
false
.
By default, leading is not included.
另请参阅 setLeadingIncluded ().
Returns the position of the line in the text engine.
Returns the rectangle covered by the line.
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.
Returns the line's position relative to the text layout's position.
另请参阅 setPosition ().
Returns the line's bounding rectangle.
另请参阅 x (), y (), textLength ()，和 width ().
Includes positive leading into the line's height if included is true; otherwise does not include leading.
By default, leading is not included.
Note that negative leading is ignored, it must be handled in the code using the text lines by letting the lines overlap.
另请参阅 leadingIncluded ().
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 cannot be split at the end of the line, it will be filled with additional characters to the next whitespace or end of the text.
Lays out the line. The line is filled from its starting position with as many characters as are specified by numColumns . In case the text cannot be split until numColumns characters, the line will be filled with as many characters to the next whitespace or end of the text.
Lays out the line. The line is filled from its starting position with as many characters as are specified by numColumns . In case the text cannot be split until numColumns characters, the line will be filled with as many characters to the next whitespace or end of the text. The provided alignmentWidth is used as reference width for alignment.
Moves the line to position pos .
另请参阅 position ().
Returns the length of the text in the line.
另请参阅 naturalTextWidth ().
Returns the start of the line from the beginning of the string passed to the QTextLayout .
Returns the line's width as specified by the layout() function.
另请参阅 naturalTextWidth (), x (), y (), textLength ()，和 rect ().
Returns the line's x position.
另请参阅 rect (), y (), textLength ()，和 width ().
Converts the x-coordinate x , to the nearest matching cursor position, depending on the cursor position type, cpos . Note that result cursor position includes possible preedit area text.
另请参阅 cursorToX ().
Returns the line's y position.
另请参阅 x (), rect (), textLength ()，和 width ().