UIActivityIndi​​catorView不居中

Question

我有一个带有UIActivityIndi​​catorView的TableViewController作为子视图,而内容加载并且它的工作方式应该如此.唯一的问题是我无法将活动指示器置于屏幕中心.

CGFloat width = CGRectGetWidth(self.view.bounds);
CGFloat height = CGRectGetHeight(self.view.bounds);

loadingIndicator = [[UIActivityIndicatorView alloc]initWithFrame:CGRectMake(width / 2, height / 2, 125, 125)];
    loadingIndicator.center = CGPointMake(width / 2, height / 2);
    loadingIndicator.activityIndicatorViewStyle = UIActivityIndicatorViewStyleWhiteLarge;
    loadingIndicator.hidesWhenStopped = YES;
    [self.tableView addSubview:loadingIndicator];
    [loadingIndicator startAnimating];

Answer 1

另外值得注意的是,大指标似乎向左和向上移动了3个像素.(swift,iOS 9.2.1)