Swift实战

swift学习也快有一个月了。文章也写了不少。今天来发布一个小ＤＥＭＯ。当操刀练手了。

主要写一个小控件，实现功能是类拟IPHONE手机打开AppStore 中的详细信息中的内容，先显示一部分，点击更多时，再加载完成。

目前只对单文本字体作处理，对于富文本的并不行。因此作为swift的操刀之作，还算是处女作吧。。。。。

源码：

整个控件的源码在:http://download.csdn.net/detail/fengsh998/7552229

效果：

其中这个“更多“的位置可以自行调整，当点击更多时，就会展示全部：

核心代码：

 //more btn
   func drawMoreInRect(moreRect:CGRect)
   {
       var ctx = UIGraphicsGetCurrentContext();
       CGContextSaveGState(ctx);

       var raduis = CGRectGetHeight(moreRect) / 2.0

       var maxX = CGRectGetMaxX(moreRect)
       var minX = CGRectGetMinX(moreRect)
       var maxY = CGRectGetMaxY(moreRect)
       var minY = CGRectGetMinY(moreRect)

       CGContextMoveToPoint(ctx,minX,minY)
       CGContextAddArcToPoint(ctx,maxX,minY,maxX,maxY,raduis)
       CGContextAddArcToPoint(ctx,maxX,maxY,minX,maxY,raduis)
       CGContextAddArcToPoint(ctx,minX,maxY,minX,minY,raduis)
       CGContextAddArcToPoint(ctx,minX,minY,maxX,minY,raduis)

       CGContextClosePath(ctx)
       if selectedHightlight
       {
           CGContextSetRGBFillColor(ctx, 29/255.0, 158/255.0, 245/255.0, 1.0)
       }
       else
       {
           CGContextSetRGBFillColor(ctx, 104/255.0, 202/255.0, 248/255.0, 1.0)
       }

       CGContextDrawPath(ctx, kCGPathFill) //根据坐标绘制路径
       CGContextRestoreGState(ctx)
   }

   override func drawRect(rect:CGRect)
   {
       var attributedString = NSMutableAttributedString(string: self.text)
       let len = countElements(String(self.text))

       let fname = self.font.fontName

       //String convert to CFString
       //let cfstr : CFString = reinterpretCast(fname.withCString(getenv))

       let mfont = self.font

       var attributes = NSMutableDictionary()

       attributes.setObject(mfont,forKey:kCTFontAttributeName)

       attributedString.addAttributes(attributes,range:NSMakeRange(0,len))

       self.attributedText = attributedString;

       var framesetter = CTFramesetterCreateWithAttributedString(attributedString)

       var Path = CGPathCreateMutable()

       var rectWidth = self.bounds.size.width

       CGPathAddRect(Path, nil ,CGRectMake(0,0,rectWidth,CGFLOAT_MAX))

       var frame = CTFramesetterCreateFrame(framesetter, CFRangeMake(0,0), Path, nil)

       var rows = CTFrameGetLines(frame)

       if let hasRows = rows?
       {
           //获取frame中的行数
           var numberOfLines = CFArrayGetCount(rows)
           //println("rows = \(numberOfLines)")

           var fontLineHeight = self.font.lineHeight

           var textOffset = self.font.ascender

           var ctx = UIGraphicsGetCurrentContext()
           CGContextSaveGState(ctx)
           //距左上位置设置
           CGContextTranslateCTM(ctx, 0, 0)
           CGContextSetTextMatrix(ctx, CGAffineTransformMakeScale(1,-1))

           for var lineNumber=0; lineNumber<numberOfLines; lineNumber++
           {
               var onlyline = CFArrayGetValueAtIndex(rows, lineNumber)
               var flush : Double = 0.0

               var onlycline :CTLine = reinterpretCast(onlyline)

               var penOffset = CTLineGetPenOffsetForFlush(onlycline, flush, rect.size.width)

               CGContextSetTextPosition(ctx, penOffset, textOffset);

               //println("第\(lineNumber)行\(onlycline)")
               //获取第onlycline行中的字形数
               //var nums = CTLineGetGlyphCount(onlycline)
               //println("本行的字符数\(nums)")

               if let mp = morepoint
               {
                   var posline = mp.row
                   var posclm = mp.column

                   var bool_lastline = (posline == numberOfLines - 1) ? true : false

                   if lineNumber == posline && !self.expand
                   {
                       var truncatedString = NSAttributedString(string: "\u2026")
                       var token = CTLineCreateWithAttributedString(truncatedString)

                       var range = CTLineGetStringRange(onlycline)
                       var maxlengthInline = range.length

                       posclm = min(posclm,maxlengthInline)

                       //获取onlycline中一黄有几个CTRun, 一般情况下，一行中只有一个CTRun
                       var runs = CTLineGetGlyphRuns(onlycline)
                       var runsNums = CFArrayGetCount(runs)

                       var rw = 0.0
                       var rh = 0.0
                       var rowx = 0.0
                       var rowy = 0.0
                       if runsNums > 0
                       {
                           //将COpaquePointer 转为CTRun
                           var run :CTRun = reinterpretCast(CFArrayGetValueAtIndex(runs, 0))
                           //println("run = \(run)")
                           var runrange = CFRange(location: 0,length:(posclm == 0) ? 1 : posclm )
                           //println("runrange = \(runrange.length)")
                           var runsrect = CTRunGetImageBounds(run, ctx, runrange)
                           //println("runsrect = \(runsrect)")
                           rw = min(runsrect.size.width,rectWidth-40)
                           rh = runsrect.size.height
                           rowx = runsrect.origin.x
                           rowy = runsrect.origin.y
                       }

                       var newline = CTLineCreateTruncatedLine(onlycline, rw, CTLineTruncationType.End, token)
                       CTLineDraw(newline, ctx)

                       var linerect = CGRectMake(rowx,rowy,0,0)
                       if newline
                       {
                           linerect = CTLineGetImageBounds(newline,ctx)
                       }
                       //println("本行文字占的rect\(linerect)")

                       //rh = min(rh,16)
                       //rh = max(rh,10)
                       rh = 16.0

                       moreBtnRect = CGRectMake(linerect.origin.x,
                           linerect.origin.y - rh + 3,40,rh)

                       self.drawMoreInRect(moreBtnRect!)

                       var moretextrect = CGRectMake(moreBtnRect!.origin.x + rh/2+3, moreBtnRect!.origin.y+2,
                           moreBtnRect!.size.width - rh, moreBtnRect!.size.height)
                       var moretext : NSString = "更多"
                       moretext.drawInRect(moretextrect, withFont: UIFont.systemFontOfSize(10))

                       break
                   }
               }

               CTLineDraw(onlycline, ctx)

               textOffset += fontLineHeight
           }//end for

           CGContextRestoreGState(ctx);

           var contentRect = CGRectMake(self.frame.origin.x, self.frame.origin.y, self.bounds.size.width, round(textOffset-self.font.ascender))

           //println("contentRect = \(contentRect)")
           if contentRect.size.height > self.bounds.size.height
           {
               dispatch_async(dispatch_get_main_queue(), {
                   self.viewFrameChangeBlock(self,contentRect)
                   })
           }

       }//end if
   }