ios开发之 改变文本行间距和字符间距

ios开发之 改变文本行间距和字符间距

#import <UIKit/UIKit.h>

@interface LineSpaceLabel : UILabel{

    CGFloat charSpace_;

    CGFloat lineSpace_;

}

@property(nonatomic, assign) CGFloat charSpace;

@property(nonatomic, assign) CGFloat lineSpace;

@end

 

 

#import "LineSpaceLabel.h"

#import <CoreText/CoreText.h>

#import<Foundation/Foundation.h>

@implementation LineSpaceLabel

@synthesize lineSpace = lineSpace_;

@synthesize charSpace = charSpace_;

- (id)initWithFrame:(CGRect)frame

{

    self = [super initWithFrame:frame];

    if (self) {

        // Initialization code

        lineSpace_ = 5.0;

        charSpace_ = 2.0;

    }

    return self;

}

-(void)awakeFromNib{

    [super awakeFromNib];

    lineSpace_ = 5.0;

    charSpace_ = 2.0;

}

-(void)setCharSpace:(CGFloat)charSpace{

    charSpace_ = charSpace;

    [self setNeedsDisplay];

}

-(void)setLineSpace:(CGFloat)lineSpace{

    lineSpace_ = lineSpace;

     [self setNeedsDisplay];

}

-(void) drawTextInRect:(CGRect)requestedRect

{

    

    //创建AttributeString

    

    NSMutableAttributedString *string =[[NSMutableAttributedString alloc]initWithString:self.text];

    

    //设置字体及大小

    

    CTFontRef helveticaBold = CTFontCreateWithName((CFStringRef)self.font.fontName,self.font.pointSize,NULL);

    

    [string addAttribute:(id)kCTFontAttributeName value:(id)helveticaBold range:NSMakeRange(0,[string length])];

    

    //设置字间距

    

    if(self.charSpace)

        

    {

        long number = self.charSpace;

        CFNumberRef num = CFNumberCreate(kCFAllocatorDefault,kCFNumberSInt8Type,&number);

        [string addAttribute:(id)kCTKernAttributeName value:(id)num range:NSMakeRange(0,[string length])];

        CFRelease(num);

    }

    

    //设置字体颜色

    

    [string addAttribute:(id)kCTForegroundColorAttributeName value:(id)(self.textColor.CGColor) range:NSMakeRange(0,[string length])];

    

    //创建文本对齐方式

    

    CTTextAlignment alignment = kCTLeftTextAlignment;

    

    if(self.textAlignment == UITextAlignmentCenter)

        

    {

        alignment = kCTCenterTextAlignment;

        

    }

    

    if(self.textAlignment == UITextAlignmentRight)

        

    {

        

        alignment = kCTRightTextAlignment;

        

    }

    

    CTParagraphStyleSetting alignmentStyle;

    

    alignmentStyle.spec = kCTParagraphStyleSpecifierAlignment;

    

    alignmentStyle.valueSize = sizeof(alignment);

    

    alignmentStyle.value = &alignment;

    

    //设置文本行间距

    

    CGFloat lineSpace = self.lineSpace;

    

    CTParagraphStyleSetting lineSpaceStyle;

    

    lineSpaceStyle.spec = kCTParagraphStyleSpecifierLineSpacingAdjustment;

    

    lineSpaceStyle.valueSize = sizeof(lineSpace);

    

    lineSpaceStyle.value =&lineSpace;

    

    //设置文本段间距

    

    CGFloat paragraphSpacing = 5.0;

    

    CTParagraphStyleSetting paragraphSpaceStyle;

    

    paragraphSpaceStyle.spec = kCTParagraphStyleSpecifierParagraphSpacing;

    

    paragraphSpaceStyle.valueSize = sizeof(CGFloat);

    

    paragraphSpaceStyle.value = ¶graphSpacing;

    

    

    

    //创建设置数组

    

    CTParagraphStyleSetting settings[ ] ={alignmentStyle,lineSpaceStyle,paragraphSpaceStyle};

    

    CTParagraphStyleRef style = CTParagraphStyleCreate(settings ,3);

    

    //给文本添加设置

    

    [string addAttribute:(id)kCTParagraphStyleAttributeName value:(id)style range:NSMakeRange(0 , [string length])];

    

    //排版

    

    CTFramesetterRef framesetter = CTFramesetterCreateWithAttributedString((CFAttributedStringRef)string);

    

    CGMutablePathRef leftColumnPath = CGPathCreateMutable();

    

    CGPathAddRect(leftColumnPath, NULL ,CGRectMake(0 , 0 ,self.bounds.size.width , self.bounds.size.height));

    

    CTFrameRef leftFrame = CTFramesetterCreateFrame(framesetter,CFRangeMake(0, 0), leftColumnPath , NULL);

    

    //翻转坐标系统（文本原来是倒的要翻转下）

    

    CGContextRef context = UIGraphicsGetCurrentContext();

    

    CGContextSetTextMatrix(context , CGAffineTransformIdentity);

    

    CGContextTranslateCTM(context , 0 ,self.bounds.size.height);

    

    CGContextScaleCTM(context, 1.0 ,-1.0);

    

    //画出文本

    

    CTFrameDraw(leftFrame,context);

    

    //释放

    

    CGPathRelease(leftColumnPath);

    

    CFRelease(framesetter);

    

    CFRelease(helveticaBold);

    

    [string release];

    

    UIGraphicsPushContext(context);

}

@end