以编程方式为UITableViewController设置UIActivityIndi​​catorView

Question

我有一个常规视图UITableViewController和一个UITableView唯一视图,我希望UIActivittyIndicatorView除了表视图之外还有一个视图.

所以我需要一个像这样的视图结构:

view (UIView):
  tableView
  activityIndicatorView

没有InterfaceBuilder,最干净的方法是什么？我想我需要覆盖这个loadView:方法,但到目前为止我还没有成功.

Answer 1

ARC和iOS 5.0+的更新(我认为旧版本需要删除,因为我们有新的,更好的API :)):

添加到您的UIViewController子类的标题.h文件:

 @property (nonatomic, weak) UIActivityIndicator *activityIndicator;

并覆盖UIViewController子类的.m文件中的方法:

- (void)loadView {
    [super loadView];
    UIActivityIndicatorView *activityIndicator = [[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleGray];
    // If you need custom color, use color property
    // activityIndicator.color = yourDesirableColor;
    [self.view addSubview:activityIndicator];
    [activityIndicator startAnimating];
    self.activityIndicator = activityIndicator;
}

- (void)viewWillLayoutSubviews {
    [super viewWillLayoutSubviews];
    CGSize viewBounds = self.view.bounds;
    self.activityIndicator.center = CGPointMake(CGRectGetMidX(viewBounds), CGRectGetMidY(viewBounds));
} 

================================================== ===========

非ARC版本,iOS <5.0:

你应该覆盖方法

-(void)loadView {
    [super loadView];
    self.activityIndicator = [[[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleGray] autorelease];
    [self.view addSubview:self.activityIndicator];
    self.activityIndicator.center = CGPointMake(self.view.frame.size.width / 2, self.view.frame.size.height / 2);
    [self.activityIndicator startAnimating];
}

另外,添加

@property (nonatomic, assign) UIActivityIndicatorView *activityIndicator;

在头文件

和

@synthesize activityIndicator;

到.m文件