How to use drawInRect:withAttributes: instead of drawAtPoint:forWidth:withFont:fontSize:lineBreakMode:baselineAdjustment: in iOS 7

问题

This method is deprecated in iOS 7.0:

drawAtPoint:forWidth:withFont:fontSize:lineBreakMode:baselineAdjustment:

Now use drawInRect:withAttributes: instead.

I can't find the attributeName of fontSize and baselineAdjustment.

Edit

Thanks @Puneet answer.

Actually, I mean if there doesn't have these key, how to implement this method in iOS 7?

Like below method:

+ (CGSize)drawWithString:(NSString *)string atPoint:(CGPoint)point forWidth:(CGFloat)width withFont:(UIFont *)font fontSize:(CGFloat)fontSize
           lineBreakMode:(IBLLineBreakMode)lineBreakMode
      baselineAdjustment:(UIBaselineAdjustment)baselineAdjustment {
    if (iOS7) {
        CGRect rect = CGRectMake(point.x, point.y, width, CGFLOAT_MAX);

        NSMutableParagraphStyle *paragraphStyle = [[NSMutableParagraphStyle alloc] init];
        paragraphStyle.lineBreakMode = lineBreakMode;

        NSDictionary *attributes = @{NSFontAttributeName: font, NSParagraphStyleAttributeName: paragraphStyle};

        [string drawInRect:rect withAttributes:attributes];

        size = CGSizeZero;
    }
    else {
        size = [string drawAtPoint:point forWidth:width withFont:font fontSize:fontSize lineBreakMode:lineBreakMode baselineAdjustment:baselineAdjustment];
    }
    return size;
}

I don't know how to pass fontSize and baselineAdjustment to

attributes dictionary.

e.g.

NSBaselineOffsetAttributeName key should pass a NSNumer to it, but the baselineAdjustment is Enum.

Isn't there have other way to pass the two variables?

回答1:

You can use NSDictionary and apply attributes like this:

NSFont *font = [NSFont fontWithName:@"Palatino-Roman" size:14.0];

NSDictionary *attrsDictionary =

[NSDictionary dictionaryWithObjectsAndKeys:
                              font, NSFontAttributeName,
                              [NSNumber numberWithFloat:1.0], NSBaselineOffsetAttributeName, nil];

Use attrsDictionary as argument.

Refer: Attributed String Programming Guide

Refer: Standard Attributes

SWIFT: IN String drawInRect is not available but we can use NSString instead:

let font = UIFont(name: "Palatino-Roman", size: 14.0)
let baselineAdjust = 1.0
let attrsDictionary =  [NSFontAttributeName:font, NSBaselineOffsetAttributeName:baselineAdjust] as [NSObject : AnyObject]
let str:NSString = "Hello World"
str.drawInRect(CGRectZero, withAttributes: attrsDictionary)

回答2:

It is a little more complicated than before and you cannot use a minimum font size, but have to use minimum font scale factor. There is also a bug in the iOS SDK, which breaks it for most use cases (see notes at the bottom). Here is what you have to do:

// Create text attributes
NSDictionary *textAttributes = @{NSFontAttributeName: [UIFont systemFontOfSize:18.0]};

// Create string drawing context
NSStringDrawingContext *drawingContext = [[NSStringDrawingContext alloc] init];
drawingContext.minimumScaleFactor = 0.5; // Half the font size

CGRect drawRect = CGRectMake(0.0, 0.0, 200.0, 100.0);
[string drawWithRect:drawRect
             options:NSStringDrawingUsesLineFragmentOrigin
          attributes:textAttributes
             context:drawingContext];

Notes:

There seems to be a bug in the iOS 7 SDK at least up to version 7.0.3: If you specify a custom font in the attributes, the miniumScaleFactor is ignored. If you pass nil for the attributes, the text is scaled correctly.
The NSStringDrawingUsesLineFragmentOrigin option is important. It tells the text drawing system, that the drawing rect's origin should be at the top left corner.
There is no way to set the baselineAdjustment using the new method. You would have to do that yourself by calling boundingRectWithSize:options:attributes:context: first and then adjusting the rect before you pass it to drawWithRect:options:attributes:context.

来源：https://stackoverflow.com/questions/19442653/how-to-use-drawinrectwithattributes-instead-of-drawatpointforwidthwithfontf

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