UIActivityIndicatorView 的使用樣本， 如何使用進度列指示器？

如何使用進度列指示器？

 

 // ImplementviewDidLoad to do additional setup after loading the view, typically from anib.

- (void)viewDidLoad {

                // 在此中載入 spinner
，注意其中的 WebView setDelegate:self
語句，有此句才能處理後續4個Web View
的重載過程

                spinner= [[UIActivityIndicatorView alloc] initWithFrame:CGRectMake(0,0,50,50)];

                [spinnersetCenter:CGPointMake(350, 350)]; // I do this because I'm in landscape mode

                [spinnersetActivityIndicatorViewStyle:UIActivityIndicatorViewStyleGray];

                [self.viewaddSubview:spinner]; // spinner is not visible until started

                [webViewsetDelegate:self];     

 

    [superviewDidLoad];

}

#pragma mark -

#pragma mark Web View lifecycle

 

-(void)webViewDidStartLoad:(UIWebView *)webView

{

                [spinnerstartAnimating];

                //opaqueview.hidden  = NO ;

}

 

-(void)webViewDidFinishLoad:(UIWebView *)webView

{

                [spinnerstopAnimating];

// [spinner release];                                     
*** 如在此使用此句將會導致出錯，畫面停止，特別是在同一畫面不停重新整理不同內容的情況下；同時也說明，有些情況下提前 release
一些變數會導致出問題。

                //opaqueview.hidden  = YES ;

}

 

- (BOOL)webView:(UIWebView *)webViewshouldStartLoadWithRequest:(NSURLRequest *)requestnavigationType:(UIWebViewNavigationType)navigationType

{

                //[spinnerstartAnimating];

                returnYES;

}

 

- (void)webView:(UIWebView *)webViewdidFailLoadWithError:(NSError *)error

{

                [spinnerstopAnimating];

}