1.-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{
2.
3. UITouch *touch = [touches anyObject];
4. CGPoint point = [touch locationInView:self];
5. start = point;
6. end = point;
7.
8.}
9.
10.-(void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event{
11.
12. UITouch *touch = [touches anyObject];
13. CGPoint point = [touch locationInView:self];
14. end = point;
15.
16. [self setNeedsDisplay];
17.}
18.
19.-(void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event{
20.
21. UITouch *touch = [touches anyObject];
22. CGPoint point = [touch locationInView:self];
23. end = point;
24.
25. [self setNeedsDisplay];
26.
27.
28.}
29.
1.#import "myView.h"
2.
3.@interface myView ()
4.{
5. CGPoint start;
6. CGPoint end;
7.}
8.@end
9.
10.
11.@implementation myView
12.
13.-(instancetype)initWithFrame:(CGRect)frame{
14. if (self = [super initWithFrame:frame]) {
15. self.backgroundColor = [UIColor whiteColor];
16. }
17. return self;
18.}
19.
20.
21.
22.-(void)drawRect:(CGRect)rect{
23.
24. if (start.x != end.x && start.y != end.y) {
25.
26. CGFloat w = fabs(end.x - start.x);
27. CGFloat h = fabs(end.y - start.y);
28.
29. CGFloat x = end.x < start.x ? end.x : start.x;
30. CGFloat y = end.y < start.y ? end.y : start.y;
31.
32. //画圆
33. UIBezierPath *path = [UIBezierPath bezierPathWithOvalInRect:
34. CGRectMake(x, y, w, h)];
35.
36. //画方
37.// UIBezierPath *path = [UIBezierPath bezierPathWithRect:CGRectMake(x, y, w, h)];
38.
39. [[UIColor redColor] setStroke];
40. [path stroke];
41. }
42.
43.}
44.
45.-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{
46.
47. UITouch *touch = [touches anyObject];
48. CGPoint point = [touch locationInView:self];
49. start = point;
50. end = point;
51.
52.}
53.
54.-(void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event{
55.
56. UITouch *touch = [touches anyObject];
57. CGPoint point = [touch locationInView:self];
58. end = point;
59.
60. [self setNeedsDisplay];
61.}
62.
63.-(void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event{
64.
65. UITouch *touch = [touches anyObject];
66. CGPoint point = [touch locationInView:self];
67. end = point;
68.
69. [self setNeedsDisplay];
70.
71.
72.}
73.
74.
75.
76.
77.@end
78.
