UIActivityIndicatorView ---- 加载进度

UIActivityIndicatorView可以用于显示某项工作在进行中，比如加载进度。在iphone中应用很广泛

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 {

 

    int width = 32, height = 32;

    

    CGRect frame = CGRectMake(100, 200, 110, 70) ;//[parent frame]; //[[UIScreen mainScreen] applicationFrame];

    int x = frame.size.width;

    int y = 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 = [[UIView alloc] initWithFrame:frame];

    theView.backgroundColor = [UIColor blackColor];

    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];

}