在UIProgressView上添加NSURLConnection加载过程

问题描述

我创建了一个 UIProgressView 。但我使用 NSTimer 到 UIProgressView的进程。现在，我需要在加载URL时集成 UIProgressView 进程。 UIProgressView的大小将取决于 NSURLConnection的数据。

I created a UIProgressView. But i used NSTimer to UIProgressView's process . Now I need to integrate UIProgressView process, when URL is loading. UIProgressView's size will be depends upon the NSURLConnection's data.

我使用以下代码 NSURLConnection 。

-(void)load {
    NSURL *myURL = [NSURL URLWithString:@"http://feeds.epicurious.com/newrecipes"];
    NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:myURL
                                                           cachePolicy:NSURLRequestReloadIgnoringLocalCacheData
                                                       timeoutInterval:60];

    [[NSURLConnection alloc] initWithRequest:request delegate:self];
}

-(void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response {
    responseData = [[NSMutableData alloc] init];
}


-(void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data {
    [responseData appendData:data];
}

-(void)connection:(NSURLConnection *)connection didFailWithError:(NSError *)error {
    [connection release];

    UIAlertView *alert = [[UIAlertView alloc] init];
    [alert setTitle:@"Warning"];
    [alert setMessage:@"Network Connection Failed?"];
    [alert setDelegate:self];
    [alert addButtonWithTitle:@"Yes"];

    [alert show];
    [alert release];

    NSLog(@"Error");
}

-(void)connectionDidFinishLoading:(NSURLConnection *)connection
{
    responsetext = [[[NSString alloc] initWithData:responseData encoding: NSASCIIStringEncoding] autorelease];
}

推荐答案

在didReceiveResponse函数中你可以获取总文件大小如下：
_totalFileSize = response.expectedContentLength; 。

In your didReceiveResponse function you could get the total filesize like so:_totalFileSize = response.expectedContentLength;.

在didReceiveData函数中然后你可以加总计收到的总字节数：
_receivedDataBytes + = [数据长度];

In your didReceiveData function you can then add up to a total bytes received counter:_receivedDataBytes += [data length];

现在，为了将进度条设置为正确的大小，您可以执行以下操作：
MyProgressBar.progress = _receivedDataBytes /（float）_totalFileSize

Now in order to set the progressbar to the correct size you can simply do:MyProgressBar.progress = _receivedDataBytes / (float)_totalFileSize

（在didReceiveData函数或代码中的其他位置）

(either in the didReceiveData function or somewhere else in your code)

不要忘记添加保存数字的变量字节到你的班级！

Don't forget to add the variables that hold the number of bytes to your class!

我希望这会有所帮助..

I hope this helps..

编辑：这是你如何实现代表以更新进度视图

Here's how you could implement the delegates in order to update progressview

-(void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response {
    _totalFileSize = response.expectedContentLength;
    responseData = [[NSMutableData alloc] init];
}


-(void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data {
   _receivedDataBytes += [data length];
   MyProgressBar.progress = _receivedDataBytes / (float)_totalFileSize;
   [responseData appendData:data];
 }

这篇关于在UIProgressView上添加NSURLConnection加载过程的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！