iphone - iPhone 中的 UIActivityIndi​​catorView 出现问题？

Question

目前我正在iPhone应用程序中工作，使用UIWebView(presentModelViewController中显示的网页)在屏幕上显示网页，然后我添加UIActivityIndi​​catorView以在加载url请求中显示，但UIActivityIndi​​catorView没有在屏幕上显示，我尝试过我的水平最好，请帮助我。

提前致谢

我尝试过这个:

- (void)viewDidLoad
{
    [super viewDidLoad];

    activity = [[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleGray];
    activity.frame=CGRectMake(140, 240, 40, 40);
    [self.view addSubview:activity]; 

    web = [[UIWebView alloc]initWithFrame:CGRectMake(0, 0, 320, 480)];
    web.delegate=self;
    web.backgroundColor=[UIColor clearColor];
    NSURL *url = [NSURL URLWithString:@"http://wrwr.rww.com/erqrrq"];
    NSURLRequest *req = [NSURLRequest requestWithURL:url];
    [web loadRequest:req];
    [self.view addSubview:web];
}

- (void)webViewDidFinishLoad:(UIWebView *)webView 
{
    [activity stopAnimating];  
}

- (void)webViewDidStartLoad:(UIWebView *)webView
{     
    [activity startAnimating];   
}

Answer 1

将您的事件指示器 View 添加到您的 webView 中，如下所示:-

 - (void)viewDidLoad
 {
[super viewDidLoad];

activity = [[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleGray];
activity.frame=CGRectMake(140, 240, 40, 40);


web = [[UIWebView alloc]initWithFrame:CGRectMake(0, 0, 320, 480)];
web.delegate=self;
web.backgroundColor=[UIColor clearColor];
NSURL *url = [NSURL URLWithString:@"http://wrwr.rww.com/erqrrq"];
NSURLRequest *req = [NSURLRequest requestWithURL:url];
[web loadRequest:req];
[web addSubview:activity];
[self.view addSubview:web];
}

 - (void)webViewDidFinishLoad:(UIWebView *)webView 
{
[activity stopAnimating];  
}

- (void)webViewDidStartLoad:(UIWebView *)webView
{     
[activity startAnimating];   
}