iPhone SDK：输入一定数量的字符后，动画就不会加载

Okay, this is the code:

好的,这是代码:

[lblMessage setText: txtEnter.text];
[lblMessage sizeToFit];

scrollingTextView.contentSize = lblMessage.frame.size;
float width = (lblMessage.frame.size.width) + (480);

[UIView beginAnimations:@"pan" context:nil];
[UIView setAnimationDuration:durationValue];
[UIView setAnimationRepeatCount:5];
scrollingTextView.contentOffset = CGPointMake(width,0);
[UIView commitAnimations];

//The scrolling text view is rotated.
scrollingTextView.transform = CGAffineTransformMakeRotation (3.14/2);

[self.navigationController setNavigationBarHidden:YES];
btnChange.transform = CGAffineTransformMakeRotation (3.14/2);
[lblMessag