NSTimer的使用Demo

不要忘记在.h里面加上：

@property(nonatomic,strong)NSTimer *timer;

#import "ViewController.h"

@interface ViewController ()

@end

NSUInteger a;

NSUInteger b = 60;

NSUInteger c;

NSUInteger d;

@implementation ViewController

- (void)viewDidLoad {

    [super viewDidLoad];

    UIButton *button = [UIButton buttonWithType:UIButtonTypeSystem];

    button.frame = CGRectMake(60, 60, 80, 60);

    [button setTitle:@"点击看效果" forState:UIControlStateNormal];

    [self.view addSubview:button];

    [button addTarget:self action:@selector(click) forControlEvents:UIControlEventTouchUpInside];

    

    // Do any additional setup after loading the view, typically from a nib.

}

-(void)click{

    self.timer = [NSTimer scheduledTimerWithTimeInterval:.5 target:self selector:@selector(time) userInfo:nil repeats:YES];

}

-(void)time{

    UILabel *label = [[UILabel alloc]init];

    label.frame = CGRectMake(60, 60, 70, 60);

    a+=20;

    if (a==180||a==220||a==300) {

        b=b+60;

    }

    else if(a==320) {

        c = label.frame.origin.x;

        d = label.frame.origin.y;

        [self theEnd];

    }

    label.frame = CGRectMake(b, 60+a, 80, 60);

    label.text = @"就是这样";

   [self.view addSubview:label];

    

}

-(void)theEnd{

    UILabel *labels = [[UILabel alloc]init];

    labels.frame = CGRectMake(240, 400, 70, 60);

    labels.text = @"theEnd";

    [self.view addSubview:labels];

    [self.timer invalidate];

    self.timer=nil;

}