boundingRect(with:options:attributes:context:)
Calculates and returns the bounding rect for the receiver drawn using the given options and display characteristics, within the specified rectangle in the current graphics context.
Declaration
func boundingRect(with size: CGSize, options: NSStringDrawingOptions = [], attributes: [NSAttributedString.Key : Any]? = nil, context: NSStringDrawingContext?) -> CGRectfunc boundingRect(with size: CGSize, options: NSString.DrawingOptions = [], attributes: [NSAttributedString.Key : Any]? = nil, context: NSStringDrawingContext?) -> CGRectParameters
- size:
The size of the rectangle to draw in.
- options:
String drawing options.
- attributes:
A dictionary of text attributes to be applied to the string. These are the same attributes that can be applied to an
NSAttributedStringobject, but in the case ofNSStringobjects, the attributes apply to the entire string, rather than ranges within the string. - context:
The string drawing context to use for the receiver, specifying minimum scale factor and tracking adjustments.
Return Value
The bounding rect for the receiver drawn using the given options and display characteristics. The rect origin returned from this method is the first glyph origin.
Discussion
To correctly draw and size multi-line text, pass usesLineFragmentOrigin in the options parameter.
This method returns fractional sizes (in the size component of the returned CGRect); to use a returned size to size views, you must raise its value to the nearest higher integer using the ceil function.
This method returns the actual bounds of the glyphs in the string. Some of the glyphs (spaces, for example) are allowed to overlap the layout constraints specified by the size passed in, so in some cases the width value of the size component of the returned CGRect can exceed the width value of the size parameter.