我已经编写了一些代码，我希望它们会随机旋转一个块到屏幕上的视图中，暂停，然后旋转出来。该动作应以半随机方式重复。这种工作方式是它显示块，旋转出来，然后在一段时间后再次显示自己：
- 它不旋转（它只旋转）
- 它永远不会改变位置
我从这段代码中遗漏了什么重要的东西？
-(void)randomlyShowBlock{
int randomTime = 1 + arc4random() % (3 - 1);
[RandomBlock setNeedsDisplay];
dispatch_after(dispatch_time(DISPATCH_TIME_NOW, randomTime * NSEC_PER_SEC), dispatch_get_main_queue(), ^(void){
int randomX = 10 + arc4random() % ((int)self.view.frame.size.width - 10);
int randomY = 10 + arc4random() % ((int)self.view.frame.size.height - 10);
RandomBlock.frame = CGRectMake(randomX, randomY, RandomBlock.frame.size.width, RandomBlock.frame.size.height);
[UIView animateWithDuration:0.4 delay:0 options:UIViewAnimationOptionCurveEaseInOut
animations:^(void) {
RandomBlock.transform = CGAffineTransformMakeRotation(DegreesToRadians(-90));
RandomBlock.backgroundColor = [[UIColor alloc] initWithRed:50.0/255.0 green:124.0/255.0 blue:203.0/255.0 alpha:1.0];
}
completion:^(BOOL finished){
[UIView animateWithDuration:0.4 delay:1 options:UIViewAnimationOptionCurveEaseInOut
animations:^(void) {
RandomBlock.transform = CGAffineTransformMakeRotation(DegreesToRadians(0));
RandomBlock.backgroundColor = [[UIColor alloc] initWithRed:220.0/255.0 green:220.0/255.0 blue:220.0/255.0 alpha:0];
}
completion:^(BOOL finished){
NSLog(@"finished animation");
//model
[self randomlyShowBlock];
}];
}];
});
}