-(void)touchesBegan:(NSSet
*)touches withEvent:(UIEvent *)event
{
    
    /*
     1,不使用动画
    
UIViewAnimationTransitionNone
    
     2,从左向右旋转翻页
    
UIViewAnimationTransitionFlipFromLeft
    
     3,从右向左旋转翻页，与UIViewAnimationTransitionFlipFromLeft相反
    
UIViewAnimationTransitionFlipFromRight
    
     4,卷曲翻页，从下往上
    
UIViewAnimationTransitionCurlUp
    
     5,卷曲翻页，从上往下
    
UIViewAnimationTransitionCurlDown
     */

    FirstViewController *firstVC=[[FirstViewController alloc]init];
    
    [UIView beginAnimations:nil context:NULL];
    //置动画块中的动画属性变化的曲线
    [UIView setAnimationCurve:UIViewAnimationCurveEaseInOut];
    //设置持续时间
    [UIView setAnimationDuration:0.5];
    //设置过渡的动画效果
    [UIView setAnimationTransition:UIViewAnimationTransitionFlipFromRight
                        forView:self.navigationController.view cache:NO];
    
    [self.navigationController pushViewController:firstVC animated:YES];
    //提交动画
    [UIView commitAnimations];

    
}