PageViewController didFinishAnimating并没有一直调用

Question

PageViewController didFinishAnimating多次滑动时未调用。

我有一个功能，可识别用户完成动画扫描，我开始每隔4秒单独移动一页。

有时在最后一次滑动时没有调用完成动画。

-(void)pageViewController:(UIPageViewController *)pageViewController didFinishAnimating:(BOOL)finished previousViewControllers:(NSArray *)previousViewControllers transitionCompleted:(BOOL)completed {

NSLog(@"\n\n\n didFinishAnimating  \n\n\n");
_isAnimateWorking = NO;

if(completed){
    _currentIndex = _nextIndex;
 }
else
{
    _currentProduct = prev_currentProduct;
   _nextIndex = prev_nextIndex;
}

[self StartMoveAloneTimer];
 }



-(void) StartMoveAloneTimer {
if (_myticker == nil) {
    _myticker = [NSTimer scheduledTimerWithTimeInterval:4.0f target:self selector:@selector(GoToNextPage) userInfo:nil repeats:YES];

}
}