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：


[cpp] ​​view plain​​​ ​​copy​​


  2. #import <QuartzCore/QuartzCore.h>
  3. #import <UIKit/UIKit.h>

  5. @interface KACircleProgressView : UIView {
  6. CAShapeLayer *_trackLayer;
  7. UIBezierPath *_trackPath;
  8. CAShapeLayer *_progressLayer;
  9. UIBezierPath *_progressPath;
  10. }

  12. @property (nonatomic, strong) UIColor *trackColor;
  13. @property (nonatomic, strong) UIColor *progressColor;
  14. @property (nonatomic) float progress;//0~1之间的数
  15. @property (nonatomic) float progressWidth;

  17. - (void)setProgress:(float)progress animated:(BOOL)animated;

  19. @end




.m文件


[cpp] ​​view plain​​​ ​​copy​​


  2. #import "KACircleProgressView.h"

  4. @implementation KACircleProgressView

  6. - (id)initWithFrame:(CGRect)frame
  7. {
  8. self = [super initWithFrame:frame];
  9. if (self) {
  10. // Initialization code
  11. _trackLayer = [CAShapeLayer new];
  12. [self.layer addSublayer:_trackLayer];
  13. _trackLayer.fillColor = nil;
  14. _trackLayer.frame = self.bounds;

  16. _progressLayer = [CAShapeLayer new];
  17. [self.layer addSublayer:_progressLayer];
  18. _progressLayer.fillColor = nil;
  19. _progressLayer.lineCap = kCALineCapRound;
  20. _progressLayer.frame = self.bounds;

  22. //默认5
  23. self.progressWidth = 5;
  24. }
  25. return self;
  26. }

  28. - (void)setTrack
  29. {
  30. _trackPath = [UIBezierPath bezierPathWithArcCenter:self.center radius:(self.bounds.size.width - _progressWidth)/ 2 startAngle:0 endAngle:M_PI * 2 clockwise:YES];;
  31. _trackLayer.path = _trackPath.CGPath;
  32. }

  34. - (void)setProgress
  35. {
  36. _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];
  37. _progressLayer.path = _progressPath.CGPath;
  38. }


  41. - (void)setProgressWidth:(float)progressWidth
  42. {
  43. _progressWidth = progressWidth;
  44. _trackLayer.lineWidth = _progressWidth;
  45. _progressLayer.lineWidth = _progressWidth;

  47. [self setTrack];
  48. [self setProgress];
  49. }

  51. - (void)setTrackColor:(UIColor *)trackColor
  52. {
  53. _trackLayer.strokeColor = trackColor.CGColor;
  54. }

  56. - (void)setProgressColor:(UIColor *)progressColor
  57. {
  58. _progressLayer.strokeColor = progressColor.CGColor;
  59. }

  61. - (void)setProgress:(float)progress
  62. {
  63. _progress = progress;

  65. [self setProgress];
  66. }

  68. - (void)setProgress:(float)progress animated:(BOOL)animated
  69. {

  71. }

  73. /*
  74. // Only override drawRect: if you perform custom drawing.
  75. // An empty implementation adversely affects performance during animation.
  76. - (void)drawRect:(CGRect)rect
  77. {
  78. // Drawing code
  79. }
  80. */

  82. @end



使用：


[cpp] ​​view plain​​​ ​​copy​​


  2. - (void)viewDidLoad
  3. {
  4. [super viewDidLoad];
  5. // Do any additional setup after loading the view, typically from a nib.
  6. KACircleProgressView *progress = [[KACircleProgressView alloc] initWithFrame:CGRectMake(0, 0, 100, 100)];
  7. [self.view addSubview:progress];
  8. progress.trackColor = [UIColor blackColor];
  9. progress.progressColor = [UIColor orangeColor];
  10. progress.progress = .7;
  11. progress.progressWidth = 10;
  12. }




最后上一张效果图：


使用CAShapeLayer与UIBezierPath画出想要的图形_#import