使用CAShapeLayer与UIBezierPath可以实现不在view的drawRect方法中就画出一些想要的图形
步骤：
1、新建UIBezierPath对象bezierPath
2、新建CAShapeLayer对象caShapeLayer
3、将bezierPath的CGPath赋值给caShapeLayer的path，即caShapeLayer.path = bezierPath.CGPath
4、把caShapeLayer添加到某个显示该图形的layer中
下面的小例子是一个环形的progress代码，有具体的使用方法
.h文件：
- #import <QuartzCore/QuartzCore.h>
- #import <UIKit/UIKit.h>
-
- @interface KACircleProgressView : UIView {
- CAShapeLayer *_trackLayer;
- UIBezierPath *_trackPath;
- CAShapeLayer *_progressLayer;
- UIBezierPath *_progressPath;
- }
-
- @property (nonatomic, strong) UIColor *trackColor;
- @property (nonatomic, strong) UIColor *progressColor;
- @property (nonatomic) float progress;
- @property (nonatomic) float progressWidth;
-
- - (void)setProgress:(float)progress animated:(BOOL)animated;
-
- @end
.m文件
- #import "KACircleProgressView.h"
-
- @implementation KACircleProgressView
-
- - (id)initWithFrame:(CGRect)frame
- {
- self = [super initWithFrame:frame];
- if (self) {
-
- _trackLayer = [CAShapeLayer new];
- [self.layer addSublayer:_trackLayer];
- _trackLayer.fillColor = nil;
- _trackLayer.frame = self.bounds;
-
- _progressLayer = [CAShapeLayer new];
- [self.layer addSublayer:_progressLayer];
- _progressLayer.fillColor = nil;
- _progressLayer.lineCap = kCALineCapRound;
- _progressLayer.frame = self.bounds;
-
-
- self.progressWidth = 5;
- }
- return self;
- }
-
- - (void)setTrack
- {
- _trackPath = [UIBezierPath bezierPathWithArcCenter:self.center radius:(self.bounds.size.width - _progressWidth)/ 2 startAngle:0 endAngle:M_PI * 2 clockwise:YES];;
- _trackLayer.path = _trackPath.CGPath;
- }
-
- - (void)setProgress
- {
- _progressPath = [UIBezierPath bezierPathWithArcCenter:self.center radius:(self.bounds.size.width - _progressWidth)/ 2 startAngle:- M_PI_2 endAngle:(M_PI * 2) * _progress - M_PI_2 clockwise:YES];
- _progressLayer.path = _progressPath.CGPath;
- }
-
-
- - (void)setProgressWidth:(float)progressWidth
- {
- _progressWidth = progressWidth;
- _trackLayer.lineWidth = _progressWidth;
- _progressLayer.lineWidth = _progressWidth;
-
- [self setTrack];
- [self setProgress];
- }
-
- - (void)setTrackColor:(UIColor *)trackColor
- {
- _trackLayer.strokeColor = trackColor.CGColor;
- }
-
- - (void)setProgressColor:(UIColor *)progressColor
- {
- _progressLayer.strokeColor = progressColor.CGColor;
- }
-
- - (void)setProgress:(float)progress
- {
- _progress = progress;
-
- [self setProgress];
- }
-
- - (void)setProgress:(float)progress animated:(BOOL)animated
- {
-
- }
-
-
- @end
使用：
- - (void)viewDidLoad
- {
- [super viewDidLoad];
-
- KACircleProgressView *progress = [[KACircleProgressView alloc] initWithFrame:CGRectMake(0, 0, 100, 100)];
- [self.view addSubview:progress];
- progress.trackColor = [UIColor blackColor];
- progress.progressColor = [UIColor orangeColor];
- progress.progress = .7;
- progress.progressWidth = 10;
- }
最后上一张效果图：
使用CAShapeLayer与UIBezierPath画出想要的图形
原文：http://www.cnblogs.com/wanghuaijun/p/5552105.html
