代碼很簡單 主要看看
+ (void)animateWithDuration:(NSTimeInterval)duration delay:(NSTimeInterval)delay options:(UIViewAnimationOptions)options animations:(void (^)(void))animations completion:(void (^)(BOOL finished))completion
方法的使用
代碼如下：
- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
arr=[[NSMutableArray alloc] init];
CGSize size=[[UIScreen mainScreen] bounds].size;
float x=size.width/3.0;
float y=size.height/3.0;
for (int i=0; i<9; i++) {
UIButton *button=[[UIButton alloc] initWithFrame:CGRectZero];
button.backgroundColor=[UIColor redColor];
int d=i%3;
int t=i/3;
button.frame=CGRectMake(0+x*d, 0+y*t,x-20, y-10);
button.tag=i;
[self.view addSubview:button];
[arr addObject:button];
}
[self showIn];
}
-(void)showIn{
int r=arc4random()%9;
UIButton *button=[arr objectAtIndex:r];
[UIView animateWithDuration:0.1 delay:1.0 options:UIViewAnimationOptionCurveLinear animations:^{
button.backgroundColor=[UIColor clearColor];
} completion:^(BOOL finished) {
button.backgroundColor=[UIColor redColor];
[self showIn];
}];
}