Struct qt_gui::QFontMetrics

source · 
#[repr(C)]
pub struct QFontMetrics { /* private fields */ }
Expand description

The QFontMetrics class provides font metrics information.

C++ class: QFontMetrics.

C++ documentation:

The QFontMetrics class provides font metrics information.

QFontMetrics functions calculate the size of characters and strings for a given font. There are three ways you can create a QFontMetrics object:

  1. Calling the QFontMetrics constructor with a QFont creates a font metrics object for a screen-compatible font, i.e. the font cannot be a printer font. If the font is changed later, the font metrics object is not updated.

    (Note: If you use a printer font the values returned may be inaccurate. Printer fonts are not always accessible so the nearest screen font is used if a printer font is supplied.)

  2. QWidget::fontMetrics() returns the font metrics for a widget's font. This is equivalent to QFontMetrics(widget->font()). If the widget's font is changed later, the font metrics object is not updated.
  3. QPainter::fontMetrics() returns the font metrics for a painter's current font. If the painter's font is changed later, the font metrics object is not updated.

Once created, the object provides functions to access the individual metrics of the font, its characters, and for strings rendered in the font.

There are several functions that operate on the font: ascent(), descent(), height(), leading() and lineSpacing() return the basic size properties of the font. The underlinePos(), overlinePos(), strikeOutPos() and lineWidth() functions, return the properties of the line that underlines, overlines or strikes out the characters. These functions are all fast.

There are also some functions that operate on the set of glyphs in the font: minLeftBearing(), minRightBearing() and maxWidth(). These are by necessity slow, and we recommend avoiding them if possible.

For each character, you can get its width(), leftBearing() and rightBearing() and find out whether it is in the font using inFont(). You can also treat the character as a string, and use the string functions on it.

The string functions include width(), to return the width of a string in pixels (or points, for a printer), boundingRect(), to return a rectangle large enough to contain the rendered string, and size(), to return the size of that rectangle.

Example:

QFont font(“times”, 24);
QFontMetrics fm(font);
int pixelsWide = fm.width(“What’s the width of this text?”);
int pixelsHigh = fm.height();

Implementations§

source§

impl QFontMetrics

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pub unsafe fn ascent(&self) -> c_int

Returns the ascent of the font.

Calls C++ function: int QFontMetrics::ascent() const.

C++ documentation:

Returns the ascent of the font.

The ascent of a font is the distance from the baseline to the highest position characters extend to. In practice, some font designers break this rule, e.g. when they put more than one accent on top of a character, or to accommodate an unusual character in an exotic language, so it is possible (though rare) that this value will be too small.

See also descent().

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pub unsafe fn average_char_width(&self) -> c_int

Returns the average width of glyphs in the font.

Calls C++ function: int QFontMetrics::averageCharWidth() const.

C++ documentation:

Returns the average width of glyphs in the font.

This function was introduced in Qt 4.2.

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pub unsafe fn bounding_rect_q_char( &self, arg1: impl CastInto<Ref<QChar>> ) -> CppBox<QRect>

Returns the rectangle that is covered by ink if character ch were to be drawn at the origin of the coordinate system.

Calls C++ function: QRect QFontMetrics::boundingRect(QChar arg1) const.

C++ documentation:

Returns the rectangle that is covered by ink if character ch were to be drawn at the origin of the coordinate system.

Note that the bounding rectangle may extend to the left of (0, 0) (e.g., for italicized fonts), and that the text output may cover all pixels in the bounding rectangle. For a space character the rectangle will usually be empty.

Note that the rectangle usually extends both above and below the base line.

Warning: The width of the returned rectangle is not the advance width of the character. Use boundingRect(const QString &) or width() instead.

See also width().

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pub unsafe fn bounding_rect_q_string( &self, text: impl CastInto<Ref<QString>> ) -> CppBox<QRect>

Returns the bounding rectangle of the characters in the string specified by text. The bounding rectangle always covers at least the set of pixels the text would cover if drawn at (0, 0).

Calls C++ function: QRect QFontMetrics::boundingRect(const QString& text) const.

C++ documentation:

Returns the bounding rectangle of the characters in the string specified by text. The bounding rectangle always covers at least the set of pixels the text would cover if drawn at (0, 0).

Note that the bounding rectangle may extend to the left of (0, 0), e.g. for italicized fonts, and that the width of the returned rectangle might be different than what the width() method returns.

If you want to know the advance width of the string (to lay out a set of strings next to each other), use width() instead.

Newline characters are processed as normal characters, not as linebreaks.

The height of the bounding rectangle is at least as large as the value returned by height().

See also width(), height(), QPainter::boundingRect(), and tightBoundingRect().

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pub unsafe fn bounding_rect_q_rect_int_q_string_int_int( &self, r: impl CastInto<Ref<QRect>>, flags: c_int, text: impl CastInto<Ref<QString>>, tabstops: c_int, tabarray: *mut c_int ) -> CppBox<QRect>

This is an overloaded function.

Calls C++ function: QRect QFontMetrics::boundingRect(const QRect& r, int flags, const QString& text, int tabstops = …, int* tabarray = …) const.

C++ documentation:

This is an overloaded function.

Returns the bounding rectangle of the characters in the string specified by text, which is the set of pixels the text would cover if drawn at (0, 0). The drawing, and hence the bounding rectangle, is constrained to the rectangle rect.

The flags argument is the bitwise OR of the following flags:

Qt::Horizontal alignment defaults to Qt::AlignLeft and vertical alignment defaults to Qt::AlignTop.

If several of the horizontal or several of the vertical alignment flags are set, the resulting alignment is undefined.

If Qt::TextExpandTabs is set in flags, then: if tabArray is non-null, it specifies a 0-terminated sequence of pixel-positions for tabs; otherwise if tabStops is non-zero, it is used as the tab spacing (in pixels).

Note that the bounding rectangle may extend to the left of (0, 0), e.g. for italicized fonts, and that the text output may cover all pixels in the bounding rectangle.

Newline characters are processed as linebreaks.

Despite the different actual character heights, the heights of the bounding rectangles of "Yes" and "yes" are the same.

The bounding rectangle returned by this function is somewhat larger than that calculated by the simpler boundingRect() function. This function uses the maximum left and right font bearings as is necessary for multi-line text to align correctly. Also, fontHeight() and lineSpacing() are used to calculate the height, rather than individual character heights.

See also width(), QPainter::boundingRect(), and Qt::Alignment.

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pub unsafe fn bounding_rect_5_int_q_string_int_int( &self, x: c_int, y: c_int, w: c_int, h: c_int, flags: c_int, text: impl CastInto<Ref<QString>>, tabstops: c_int, tabarray: *mut c_int ) -> CppBox<QRect>

This is an overloaded function.

Calls C++ function: QRect QFontMetrics::boundingRect(int x, int y, int w, int h, int flags, const QString& text, int tabstops = …, int* tabarray = …) const.

C++ documentation:

This is an overloaded function.

Returns the bounding rectangle for the given text within the rectangle specified by the x and y coordinates, width, and height.

If Qt::TextExpandTabs is set in flags and tabArray is non-null, it specifies a 0-terminated sequence of pixel-positions for tabs; otherwise, if tabStops is non-zero, it is used as the tab spacing (in pixels).

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pub unsafe fn bounding_rect_q_rect_int_q_string_int( &self, r: impl CastInto<Ref<QRect>>, flags: c_int, text: impl CastInto<Ref<QString>>, tabstops: c_int ) -> CppBox<QRect>

This is an overloaded function.

Calls C++ function: QRect QFontMetrics::boundingRect(const QRect& r, int flags, const QString& text, int tabstops = …) const.

C++ documentation:

This is an overloaded function.

Returns the bounding rectangle of the characters in the string specified by text, which is the set of pixels the text would cover if drawn at (0, 0). The drawing, and hence the bounding rectangle, is constrained to the rectangle rect.

The flags argument is the bitwise OR of the following flags:

Qt::Horizontal alignment defaults to Qt::AlignLeft and vertical alignment defaults to Qt::AlignTop.

If several of the horizontal or several of the vertical alignment flags are set, the resulting alignment is undefined.

If Qt::TextExpandTabs is set in flags, then: if tabArray is non-null, it specifies a 0-terminated sequence of pixel-positions for tabs; otherwise if tabStops is non-zero, it is used as the tab spacing (in pixels).

Note that the bounding rectangle may extend to the left of (0, 0), e.g. for italicized fonts, and that the text output may cover all pixels in the bounding rectangle.

Newline characters are processed as linebreaks.

Despite the different actual character heights, the heights of the bounding rectangles of "Yes" and "yes" are the same.

The bounding rectangle returned by this function is somewhat larger than that calculated by the simpler boundingRect() function. This function uses the maximum left and right font bearings as is necessary for multi-line text to align correctly. Also, fontHeight() and lineSpacing() are used to calculate the height, rather than individual character heights.

See also width(), QPainter::boundingRect(), and Qt::Alignment.

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pub unsafe fn bounding_rect_q_rect_int_q_string( &self, r: impl CastInto<Ref<QRect>>, flags: c_int, text: impl CastInto<Ref<QString>> ) -> CppBox<QRect>

This is an overloaded function.

Calls C++ function: QRect QFontMetrics::boundingRect(const QRect& r, int flags, const QString& text) const.

C++ documentation:

This is an overloaded function.

Returns the bounding rectangle of the characters in the string specified by text, which is the set of pixels the text would cover if drawn at (0, 0). The drawing, and hence the bounding rectangle, is constrained to the rectangle rect.

The flags argument is the bitwise OR of the following flags:

Qt::Horizontal alignment defaults to Qt::AlignLeft and vertical alignment defaults to Qt::AlignTop.

If several of the horizontal or several of the vertical alignment flags are set, the resulting alignment is undefined.

If Qt::TextExpandTabs is set in flags, then: if tabArray is non-null, it specifies a 0-terminated sequence of pixel-positions for tabs; otherwise if tabStops is non-zero, it is used as the tab spacing (in pixels).

Note that the bounding rectangle may extend to the left of (0, 0), e.g. for italicized fonts, and that the text output may cover all pixels in the bounding rectangle.

Newline characters are processed as linebreaks.

Despite the different actual character heights, the heights of the bounding rectangles of "Yes" and "yes" are the same.

The bounding rectangle returned by this function is somewhat larger than that calculated by the simpler boundingRect() function. This function uses the maximum left and right font bearings as is necessary for multi-line text to align correctly. Also, fontHeight() and lineSpacing() are used to calculate the height, rather than individual character heights.

See also width(), QPainter::boundingRect(), and Qt::Alignment.

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pub unsafe fn bounding_rect_5_int_q_string_int( &self, x: c_int, y: c_int, w: c_int, h: c_int, flags: c_int, text: impl CastInto<Ref<QString>>, tabstops: c_int ) -> CppBox<QRect>

This is an overloaded function.

Calls C++ function: QRect QFontMetrics::boundingRect(int x, int y, int w, int h, int flags, const QString& text, int tabstops = …) const.

C++ documentation:

This is an overloaded function.

Returns the bounding rectangle for the given text within the rectangle specified by the x and y coordinates, width, and height.

If Qt::TextExpandTabs is set in flags and tabArray is non-null, it specifies a 0-terminated sequence of pixel-positions for tabs; otherwise, if tabStops is non-zero, it is used as the tab spacing (in pixels).

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pub unsafe fn bounding_rect_5_int_q_string( &self, x: c_int, y: c_int, w: c_int, h: c_int, flags: c_int, text: impl CastInto<Ref<QString>> ) -> CppBox<QRect>

This is an overloaded function.

Calls C++ function: QRect QFontMetrics::boundingRect(int x, int y, int w, int h, int flags, const QString& text) const.

C++ documentation:

This is an overloaded function.

Returns the bounding rectangle for the given text within the rectangle specified by the x and y coordinates, width, and height.

If Qt::TextExpandTabs is set in flags and tabArray is non-null, it specifies a 0-terminated sequence of pixel-positions for tabs; otherwise, if tabStops is non-zero, it is used as the tab spacing (in pixels).

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pub unsafe fn cap_height(&self) -> c_int

Returns the cap height of the font.

Calls C++ function: int QFontMetrics::capHeight() const.

C++ documentation:

Returns the cap height of the font.

The cap height of a font is the height of a capital letter above the baseline. It specifically is the height of capital letters that are flat - such as H or I - as opposed to round letters such as O, or pointed letters like A, both of which may display overshoot.

This function was introduced in Qt 5.8.

See also ascent().

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pub unsafe fn char_width( &self, str: impl CastInto<Ref<QString>>, pos: c_int ) -> c_int

Returns the width of the character at position pos in the string text.

Calls C++ function: int QFontMetrics::charWidth(const QString& str, int pos) const.

C++ documentation:

Returns the width of the character at position pos in the string text.

The whole string is needed, as the glyph drawn may change depending on the context (the letter before and after the current one) for some languages (e.g. Arabic).

This function also takes non spacing marks and ligatures into account.

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pub unsafe fn copy_from( &self, arg1: impl CastInto<Ref<QFontMetrics>> ) -> Ref<QFontMetrics>

Assigns the font metrics fm.

Calls C++ function: QFontMetrics& QFontMetrics::operator=(const QFontMetrics& arg1).

C++ documentation:

Assigns the font metrics fm.

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pub unsafe fn descent(&self) -> c_int

Returns the descent of the font.

Calls C++ function: int QFontMetrics::descent() const.

C++ documentation:

Returns the descent of the font.

The descent is the distance from the base line to the lowest point characters extend to. In practice, some font designers break this rule, e.g. to accommodate an unusual character in an exotic language, so it is possible (though rare) that this value will be too small.

See also ascent().

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pub unsafe fn elided_text_4a( &self, text: impl CastInto<Ref<QString>>, mode: TextElideMode, width: c_int, flags: c_int ) -> CppBox<QString>

If the string text is wider than width, returns an elided version of the string (i.e., a string with "..." in it). Otherwise, returns the original string.

Calls C++ function: QString QFontMetrics::elidedText(const QString& text, Qt::TextElideMode mode, int width, int flags = …) const.

C++ documentation:

If the string text is wider than width, returns an elided version of the string (i.e., a string with “…” in it). Otherwise, returns the original string.

The mode parameter specifies whether the text is elided on the left (e.g., "...tech"), in the middle (e.g., "Tr...ch"), or on the right (e.g., "Trol...").

The width is specified in pixels, not characters.

The flags argument is optional and currently only supports Qt::TextShowMnemonic as value.

The elide mark follows the layoutdirection. For example, it will be on the right side of the text for right-to-left layouts if the mode is Qt::ElideLeft, and on the left side of the text if the mode is Qt::ElideRight.

This function was introduced in Qt 4.2.

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pub unsafe fn elided_text_3a( &self, text: impl CastInto<Ref<QString>>, mode: TextElideMode, width: c_int ) -> CppBox<QString>

If the string text is wider than width, returns an elided version of the string (i.e., a string with "..." in it). Otherwise, returns the original string.

Calls C++ function: QString QFontMetrics::elidedText(const QString& text, Qt::TextElideMode mode, int width) const.

C++ documentation:

If the string text is wider than width, returns an elided version of the string (i.e., a string with “…” in it). Otherwise, returns the original string.

The mode parameter specifies whether the text is elided on the left (e.g., "...tech"), in the middle (e.g., "Tr...ch"), or on the right (e.g., "Trol...").

The width is specified in pixels, not characters.

The flags argument is optional and currently only supports Qt::TextShowMnemonic as value.

The elide mark follows the layoutdirection. For example, it will be on the right side of the text for right-to-left layouts if the mode is Qt::ElideLeft, and on the left side of the text if the mode is Qt::ElideRight.

This function was introduced in Qt 4.2.

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pub unsafe fn font_dpi(&self) -> c_double

Available on cpp_lib_version="5.14.0" only.

Returns the font DPI.

Calls C++ function: double QFontMetrics::fontDpi() const.

C++ documentation:

Returns the font DPI.

This function was introduced in Qt 5.14.

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pub unsafe fn height(&self) -> c_int

Returns the height of the font.

Calls C++ function: int QFontMetrics::height() const.

C++ documentation:

Returns the height of the font.

This is always equal to ascent()+descent().

See also leading() and lineSpacing().

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pub unsafe fn horizontal_advance_q_string_int( &self, arg1: impl CastInto<Ref<QString>>, len: c_int ) -> c_int

Available on cpp_lib_version="5.11.3" or cpp_lib_version="5.12.2" or cpp_lib_version="5.13.0" or cpp_lib_version="5.14.0" only.

Returns the horizontal advance in pixels of the first len characters of text. If len is negative (the default), the entire string is used.

Calls C++ function: int QFontMetrics::horizontalAdvance(const QString& arg1, int len = …) const.

C++ documentation:

Returns the horizontal advance in pixels of the first len characters of text. If len is negative (the default), the entire string is used.

This is the distance appropriate for drawing a subsequent character after text.

This function was introduced in Qt 5.11.

See also boundingRect().

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pub unsafe fn horizontal_advance_q_char( &self, arg1: impl CastInto<Ref<QChar>> ) -> c_int

Available on cpp_lib_version="5.11.3" or cpp_lib_version="5.12.2" or cpp_lib_version="5.13.0" or cpp_lib_version="5.14.0" only.

This is an overloaded function.

Calls C++ function: int QFontMetrics::horizontalAdvance(QChar arg1) const.

C++ documentation:

This is an overloaded function.

Bearings

Returns the horizontal advance of character ch in pixels. This is a distance appropriate for drawing a subsequent character after ch.

Some of the metrics are described in the image. The central dark rectangles cover the logical horizontalAdvance() of each character. The outer pale rectangles cover the leftBearing() and rightBearing() of each character. Notice that the bearings of "f" in this particular font are both negative, while the bearings of "o" are both positive.

Warning: This function will produce incorrect results for Arabic characters or non-spacing marks in the middle of a string, as the glyph shaping and positioning of marks that happens when processing strings cannot be taken into account. When implementing an interactive text control, use QTextLayout instead.

This function was introduced in Qt 5.11.

See also boundingRect().

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pub unsafe fn horizontal_advance_q_string( &self, arg1: impl CastInto<Ref<QString>> ) -> c_int

Available on cpp_lib_version="5.11.3" or cpp_lib_version="5.12.2" or cpp_lib_version="5.13.0" or cpp_lib_version="5.14.0" only.

Returns the horizontal advance in pixels of the first len characters of text. If len is negative (the default), the entire string is used.

Calls C++ function: int QFontMetrics::horizontalAdvance(const QString& arg1) const.

C++ documentation:

Returns the horizontal advance in pixels of the first len characters of text. If len is negative (the default), the entire string is used.

This is the distance appropriate for drawing a subsequent character after text.

This function was introduced in Qt 5.11.

See also boundingRect().

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pub unsafe fn in_font(&self, arg1: impl CastInto<Ref<QChar>>) -> bool

Returns true if character ch is a valid character in the font; otherwise returns false.

Calls C++ function: bool QFontMetrics::inFont(QChar arg1) const.

C++ documentation:

Returns true if character ch is a valid character in the font; otherwise returns false.

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pub unsafe fn in_font_ucs4(&self, ucs4: c_uint) -> bool

Returns true if the character ucs4 encoded in UCS-4/UTF-32 is a valid character in the font; otherwise returns false.

Calls C++ function: bool QFontMetrics::inFontUcs4(unsigned int ucs4) const.

C++ documentation:

Returns true if the character ucs4 encoded in UCS-4/UTF-32 is a valid character in the font; otherwise returns false.

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pub unsafe fn leading(&self) -> c_int

Returns the leading of the font.

Calls C++ function: int QFontMetrics::leading() const.

C++ documentation:

Returns the leading of the font.

This is the natural inter-line spacing.

See also height() and lineSpacing().

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pub unsafe fn left_bearing(&self, arg1: impl CastInto<Ref<QChar>>) -> c_int

Returns the left bearing of character ch in the font.

Calls C++ function: int QFontMetrics::leftBearing(QChar arg1) const.

C++ documentation:

Returns the left bearing of character ch in the font.

The left bearing is the right-ward distance of the left-most pixel of the character from the logical origin of the character. This value is negative if the pixels of the character extend to the left of the logical origin.

See width(QChar) for a graphical description of this metric.

See also rightBearing(), minLeftBearing(), and width().

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pub unsafe fn line_spacing(&self) -> c_int

Returns the distance from one base line to the next.

Calls C++ function: int QFontMetrics::lineSpacing() const.

C++ documentation:

Returns the distance from one base line to the next.

This value is always equal to leading()+height().

See also height() and leading().

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pub unsafe fn line_width(&self) -> c_int

Returns the width of the underline and strikeout lines, adjusted for the point size of the font.

Calls C++ function: int QFontMetrics::lineWidth() const.

C++ documentation:

Returns the width of the underline and strikeout lines, adjusted for the point size of the font.

See also underlinePos(), overlinePos(), and strikeOutPos().

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pub unsafe fn max_width(&self) -> c_int

Returns the width of the widest character in the font.

Calls C++ function: int QFontMetrics::maxWidth() const.

C++ documentation:

Returns the width of the widest character in the font.

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pub unsafe fn min_left_bearing(&self) -> c_int

Returns the minimum left bearing of the font.

Calls C++ function: int QFontMetrics::minLeftBearing() const.

C++ documentation:

Returns the minimum left bearing of the font.

This is the smallest leftBearing(char) of all characters in the font.

Note that this function can be very slow if the font is large.

See also minRightBearing() and leftBearing().

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pub unsafe fn min_right_bearing(&self) -> c_int

Returns the minimum right bearing of the font.

Calls C++ function: int QFontMetrics::minRightBearing() const.

C++ documentation:

Returns the minimum right bearing of the font.

This is the smallest rightBearing(char) of all characters in the font.

Note that this function can be very slow if the font is large.

See also minLeftBearing() and rightBearing().

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pub unsafe fn new_1a(arg1: impl CastInto<Ref<QFont>>) -> CppBox<QFontMetrics>

Constructs a font metrics object for font.

Calls C++ function: [constructor] void QFontMetrics::QFontMetrics(const QFont& arg1).

C++ documentation:

Constructs a font metrics object for font.

The font metrics will be compatible with the paintdevice used to create font.

The font metrics object holds the information for the font that is passed in the constructor at the time it is created, and is not updated if the font's attributes are changed later.

Use QFontMetrics(const QFont &, QPaintDevice *) to get the font metrics that are compatible with a certain paint device.

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pub unsafe fn new_2a( arg1: impl CastInto<Ref<QFont>>, pd: impl CastInto<Ptr<QPaintDevice>> ) -> CppBox<QFontMetrics>

Constructs a font metrics object for font and paintdevice.

Calls C++ function: [constructor] void QFontMetrics::QFontMetrics(const QFont& arg1, QPaintDevice* pd).

C++ documentation:

Constructs a font metrics object for font and paintdevice.

The font metrics will be compatible with the paintdevice passed. If the paintdevice is 0, the metrics will be screen-compatible, ie. the metrics you get if you use the font for drawing text on a widgets or pixmaps, not on a QPicture or QPrinter.

The font metrics object holds the information for the font that is passed in the constructor at the time it is created, and is not updated if the font's attributes are changed later.

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pub unsafe fn new_copy( arg1: impl CastInto<Ref<QFontMetrics>> ) -> CppBox<QFontMetrics>

Constructs a copy of fm.

Calls C++ function: [constructor] void QFontMetrics::QFontMetrics(const QFontMetrics& arg1).

C++ documentation:

Constructs a copy of fm.

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pub unsafe fn overline_pos(&self) -> c_int

Returns the distance from the base line to where an overline should be drawn.

Calls C++ function: int QFontMetrics::overlinePos() const.

C++ documentation:

Returns the distance from the base line to where an overline should be drawn.

See also underlinePos(), strikeOutPos(), and lineWidth().

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pub unsafe fn right_bearing(&self, arg1: impl CastInto<Ref<QChar>>) -> c_int

Returns the right bearing of character ch in the font.

Calls C++ function: int QFontMetrics::rightBearing(QChar arg1) const.

C++ documentation:

Returns the right bearing of character ch in the font.

The right bearing is the left-ward distance of the right-most pixel of the character from the logical origin of a subsequent character. This value is negative if the pixels of the character extend to the right of the width() of the character.

See width() for a graphical description of this metric.

See also leftBearing(), minRightBearing(), and width().

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pub unsafe fn size_4a( &self, flags: c_int, str: impl CastInto<Ref<QString>>, tabstops: c_int, tabarray: *mut c_int ) -> CppBox<QSize>

Returns the size in pixels of text.

Calls C++ function: QSize QFontMetrics::size(int flags, const QString& str, int tabstops = …, int* tabarray = …) const.

C++ documentation:

Returns the size in pixels of text.

The flags argument is the bitwise OR of the following flags:

If Qt::TextExpandTabs is set in flags, then: if tabArray is non-null, it specifies a 0-terminated sequence of pixel-positions for tabs; otherwise if tabStops is non-zero, it is used as the tab spacing (in pixels).

Newline characters are processed as linebreaks.

Despite the different actual character heights, the heights of the bounding rectangles of "Yes" and "yes" are the same.

See also boundingRect().

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pub unsafe fn size_3a( &self, flags: c_int, str: impl CastInto<Ref<QString>>, tabstops: c_int ) -> CppBox<QSize>

Returns the size in pixels of text.

Calls C++ function: QSize QFontMetrics::size(int flags, const QString& str, int tabstops = …) const.

C++ documentation:

Returns the size in pixels of text.

The flags argument is the bitwise OR of the following flags:

If Qt::TextExpandTabs is set in flags, then: if tabArray is non-null, it specifies a 0-terminated sequence of pixel-positions for tabs; otherwise if tabStops is non-zero, it is used as the tab spacing (in pixels).

Newline characters are processed as linebreaks.

Despite the different actual character heights, the heights of the bounding rectangles of "Yes" and "yes" are the same.

See also boundingRect().

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pub unsafe fn size_2a( &self, flags: c_int, str: impl CastInto<Ref<QString>> ) -> CppBox<QSize>

Returns the size in pixels of text.

Calls C++ function: QSize QFontMetrics::size(int flags, const QString& str) const.

C++ documentation:

Returns the size in pixels of text.

The flags argument is the bitwise OR of the following flags:

If Qt::TextExpandTabs is set in flags, then: if tabArray is non-null, it specifies a 0-terminated sequence of pixel-positions for tabs; otherwise if tabStops is non-zero, it is used as the tab spacing (in pixels).

Newline characters are processed as linebreaks.

Despite the different actual character heights, the heights of the bounding rectangles of "Yes" and "yes" are the same.

See also boundingRect().

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pub unsafe fn strike_out_pos(&self) -> c_int

Returns the distance from the base line to where the strikeout line should be drawn.

Calls C++ function: int QFontMetrics::strikeOutPos() const.

C++ documentation:

Returns the distance from the base line to where the strikeout line should be drawn.

See also underlinePos(), overlinePos(), and lineWidth().

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pub unsafe fn swap(&self, other: impl CastInto<Ref<QFontMetrics>>)

Swaps this font metrics instance with other. This function is very fast and never fails.

Calls C++ function: void QFontMetrics::swap(QFontMetrics& other).

C++ documentation:

Swaps this font metrics instance with other. This function is very fast and never fails.

This function was introduced in Qt 5.0.

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pub unsafe fn tight_bounding_rect( &self, text: impl CastInto<Ref<QString>> ) -> CppBox<QRect>

Returns a tight bounding rectangle around the characters in the string specified by text. The bounding rectangle always covers at least the set of pixels the text would cover if drawn at (0, 0).

Calls C++ function: QRect QFontMetrics::tightBoundingRect(const QString& text) const.

C++ documentation:

Returns a tight bounding rectangle around the characters in the string specified by text. The bounding rectangle always covers at least the set of pixels the text would cover if drawn at (0, 0).

Note that the bounding rectangle may extend to the left of (0, 0), e.g. for italicized fonts, and that the width of the returned rectangle might be different than what the width() method returns.

If you want to know the advance width of the string (to lay out a set of strings next to each other), use width() instead.

Newline characters are processed as normal characters, not as linebreaks.

Warning: Calling this method is very slow on Windows.

This function was introduced in Qt 4.3.

See also width(), height(), and boundingRect().

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pub unsafe fn underline_pos(&self) -> c_int

Returns the distance from the base line to where an underscore should be drawn.

Calls C++ function: int QFontMetrics::underlinePos() const.

C++ documentation:

Returns the distance from the base line to where an underscore should be drawn.

See also overlinePos(), strikeOutPos(), and lineWidth().

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pub unsafe fn width_q_string_int( &self, arg1: impl CastInto<Ref<QString>>, len: c_int ) -> c_int

Returns the width in pixels of the first len characters of text. If len is negative (the default), the entire string is used.

Calls C++ function: int QFontMetrics::width(const QString& arg1, int len = …) const.

C++ documentation:

Returns the width in pixels of the first len characters of text. If len is negative (the default), the entire string is used.

Note that this value is not equal to boundingRect().width(); boundingRect() returns a rectangle describing the pixels this string will cover whereas width() returns the distance to where the next string should be drawn.

See also boundingRect().

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pub unsafe fn width_q_string2_int( &self, arg1: impl CastInto<Ref<QString>>, len: c_int, flags: c_int ) -> c_int

Calls C++ function: int QFontMetrics::width(const QString& arg1, int len, int flags) const.

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pub unsafe fn width_q_char(&self, arg1: impl CastInto<Ref<QChar>>) -> c_int

This is an overloaded function.

Calls C++ function: int QFontMetrics::width(QChar arg1) const.

C++ documentation:

This is an overloaded function.

Bearings

Returns the logical width of character ch in pixels. This is a distance appropriate for drawing a subsequent character after ch.

Some of the metrics are described in the image to the right. The central dark rectangles cover the logical width() of each character. The outer pale rectangles cover the leftBearing() and rightBearing() of each character. Notice that the bearings of "f" in this particular font are both negative, while the bearings of "o" are both positive.

Warning: This function will produce incorrect results for Arabic characters or non-spacing marks in the middle of a string, as the glyph shaping and positioning of marks that happens when processing strings cannot be taken into account. When implementing an interactive text control, use QTextLayout instead.

See also boundingRect().

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pub unsafe fn width_q_string(&self, arg1: impl CastInto<Ref<QString>>) -> c_int

Returns the width in pixels of the first len characters of text. If len is negative (the default), the entire string is used.

Calls C++ function: int QFontMetrics::width(const QString& arg1) const.

C++ documentation:

Returns the width in pixels of the first len characters of text. If len is negative (the default), the entire string is used.

Note that this value is not equal to boundingRect().width(); boundingRect() returns a rectangle describing the pixels this string will cover whereas width() returns the distance to where the next string should be drawn.

See also boundingRect().

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pub unsafe fn x_height(&self) -> c_int

Returns the 'x' height of the font. This is often but not always the same as the height of the character 'x'.

Calls C++ function: int QFontMetrics::xHeight() const.

C++ documentation:

Returns the ‘x’ height of the font. This is often but not always the same as the height of the character ‘x’.

Trait Implementations§

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impl CppDeletable for QFontMetrics

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unsafe fn delete(&self)

Destroys the font metrics object and frees all allocated resources.

Calls C++ function: [destructor] void QFontMetrics::~QFontMetrics().

C++ documentation:

Destroys the font metrics object and frees all allocated resources.

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impl PartialEq<Ref<QFontMetrics>> for QFontMetrics

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fn eq(&self, other: &Ref<QFontMetrics>) -> bool

Returns true if other is equal to this object; otherwise returns false.

Calls C++ function: bool QFontMetrics::operator==(const QFontMetrics& other) const.

C++ documentation:

Returns true if other is equal to this object; otherwise returns false.

Two font metrics are considered equal if they were constructed from the same QFont and the paint devices they were constructed for are considered compatible.

See also operator!=().

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fn ne(&self, other: &Rhs) -> bool

This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

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Performs the conversion. Read more
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fn into(self) -> U

Calls U::from(self).

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