用法一：只显示不停旋转的进度滚轮指示器。
//显示进度滚轮指示器
-(void)showWaiting {
progressInd=[[UIActivityIndicatorView alloc]initWithActivityIndicatorStyle:
UIActivityIndicatorViewStyleWhiteLarge];
progressInd.center=CGPointMake(self.view.center.x,240);
[self.navigationController.view addSubview:progressInd];
[progressInd startAnimating];
}
//消除滚动轮指示器
-(void)hideWaiting
{
[progressInd stopAnimating];
}
用法二：带有半透明背景的进度轮指示器。
//显示进度滚轮指示器
-(void)showWaiting:(UIView *)parent {
intwidth=32,height=32;CGRect frame = CGRectMake(100,200,110,70) ;//[parent frame]; //[[UIScreen mainScreen] applicationFrame];intx = frame.size.width;inty = frame.size.height;frame = CGRectMake((x -width) /2, (y -height) /2,width,height);UIActivityIndicatorView* progressInd = [[UIActivityIndicatorView alloc]initWithFrame:frame];[progressInd startAnimating];progressInd.activityIndicatorViewStyle = UIActivityIndicatorViewStyleWhiteLarge;
frame = CGRectMake((x - 70)/2, (y - height) / 2 + height, 80, 20);
UILabel *waitingLable = [[UILabel alloc] initWithFrame:frame];
waitingLable.text = @"Loading...";
waitingLable.textColor = [UIColor whiteColor];
waitingLable.font = [UIFont systemFontOfSize:15];
waitingLable.backgroundColor = [UIColor clearColor];
frame =CGRectMake(100,200,110,70) ;//[parent frame];UIView*theView = [[UIViewalloc] initWithFrame:frame];theView.backgroundColor= [UIColorblackColor];theView.alpha=0.7;[theView addSubview:progressInd];
[theView addSubview:waitingLable];
[progressInd release];
[waitingLable release];
[theView setTag:9999];[parent addSubview:theView];[theView release];
}
//消除滚动轮指示器
-(void)hideWaiting
{
[[self.view viewWithTag:9999] removeFromSuperview];
}
另一种实现
UIActivityIndicatorView *activityView = [[[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleWhiteLarge] autorelease];
activityView.frame = CGRectMake(139.0f-18.0f, 50.0f, 37.0f, 37.0f);
[self.loadingView addSubview:activityView];
[activityView startAnimating];
activityView.center = self.loadingView.center;
[activityView stopAnimating];