I a开发者_开发知识库m trying to get the width of an NSString (ex. NSString *myString = @"hello"). Is there a way to do this?
Thanks.
Here's a relatively simple approach. Just create an NSAttributedString with the appropriate font and ask for its size:
- (CGFloat)widthOfString:(NSString *)string withFont:(NSFont *)font {
NSDictionary *attributes = [NSDictionary dictionaryWithObjectsAndKeys:font, NSFontAttributeName, nil];
return [[[NSAttributedString alloc] initWithString:string attributes:attributes] size].width;
}
UIFont * font = [UIFont systemFontOfSize:15];
CGSize stringSize = [aString sizeWithFont:font];
CGFloat width = stringSize.width;
Using the UILabel's attributed string:
- (CGSize)getStringSizeWithText:(NSString *)string font:(UIFont *)font{
UILabel *label = [[UILabel alloc] init];
label.text = string;
label.font = font;
return label.attributedText.size;
}
Send the string a sizeWithAttributes:
message, passing a dictionary containing the attributes with which you want to measure the string.
i dont know if you are suppose to use this in cocoa touch. if it is, then:
- (CGFloat)widthOfString:(NSString *)string withFont:(NSFont *)font {
NSDictionary *attributes = [NSDictionary dictionaryWithObjectsAndKeys:font, NSFontAttributeName, nil];
return [[[NSAttributedString alloc] initWithString:string attributes:attributes] size].width;
}
wont work.
in cocoa touch, you gotta add coretext framework and import the header and write your code like this:
UIFont *font = [UIFont fontWithName:@"HelveticaNeue-BoldItalic" size:DEFAULT_FONT_SIZE];
// NSLog(@"%@", NSFontAttributeName);
NSDictionary *attributes = [NSDictionary dictionaryWithObjectsAndKeys:font, (NSString *)kCTFontAttributeName, nil];
but, GEE!!!!!
NSMutableAttributedString *as = [[NSMutableAttributedString alloc] initWithString:self.caption attributes:attributes];
[as size].width;
there's no size this method in NSMutableAttributedString!
finally, this would work
[self.caption sizeWithFont:font].width
as for ios 7 and up this is the correct way:
NSString * buttonTitle = @"demo title";
CGSize stringSize = [buttonTitle sizeWithAttributes:@{NSFontAttributeName: [UIFont systemFontOfSize:17.0f]}];
This works with iOS 14.5
Objective-C
Define attributes:
NSDictionary *attributes = @{
NSFontAttributeName: [UIFont fontWithName:@"Helvetica" size:25],
NSStrokeWidthAttributeName: @(0),
NSStrokeColorAttributeName: [UIColor blackColor]
};
Get width and height:
- (CGFloat)widthOfString:(NSString *)string {
CGSize stringSize = [string sizeWithAttributes:attributes];
return stringSize.width;
}
- (CGFloat)heightOfString:(NSString *)string {
CGSize stringSize = [string sizeWithAttributes:attributes];
return stringSize.height;
}
Sorry my question was not detailed enough and is not exactly what I'm trying to do. I am using a text storage, layout manager and a text container. The solution is to use the layout manager to determine the rectangle that bounds the rect. Here is the code.
NSTextStorage *textStorage = [[NSTextStorage alloc] initWithString:@"hello"];
NSLayoutManager *layoutManager = [[NSLayoutManager alloc] init];
NSTextContainer *textContainer = [[NSTextContainer alloc] init];
[layoutManager addTextContainer:textContainer];
[textContainer release];
[textStorage addLayoutManager:layoutManager];
[layoutManager release];
//Figure out the bounding rectangle
NSRect stringRect = [layoutManager boundingRectForGlyphRange:NSMakeRange(0, [layoutManager numberOfGlyphs]) inTextContainer:textContainer];
UIKit has a nice addition to NSString, making sizeWithAttributes: a bit lighter:
CGSize titleSize = [title sizeWithFont:titleFont
constrainedToSize:contentCellSize
lineBreakMode:UILineBreakModeWordWrap];
Here's Stephen's solution in Clozure Common Lisp, when using the Objective C bridge. I came across this post when searching for a solution, and I just rewrote Stephen's version which worked fine for me. Others using Clozure might find this helpful:
(defun string-width (str font)
(let* ((dict (#/dictionaryWithObjectsAndKeys: ns:ns-mutable-dictionary
font #$NSFontAttributeName
ccl:+null-ptr+))
(attr (#/initWithString:attributes: (#/alloc ns:ns-attributed-string)
(ccl::%make-nsstring str)
dict))
(size (#/size attr)))
(ns:ns-size-width size)))
This will work. You can try it.
NSDictionary *attrDict = @{NSFontAttributeName : [GenericUtility getOpenSansRegularFontSize:12]};
CGSize stringBoundingBox = [selectedReservationModel.DateLabel sizeWithAttributes: attrDict];
lblDeliveryDateWidth = stringBoundingBox.width;
Just in case you are wondering how to check a label size, you should use the UIFont, instead of the NSFont (not even sure if exists)
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