如何使用 AFNetworking 在 UILabel 中设置 UIProgressView 的下载状态？

Posted 2023-02-24

【中文标题】如何使用 AFNetworking 在 UILabel 中设置 UIProgressView 的下载状态？

【英文标题】：How to set download status of UIProgressView in UILabel using AFNetworking?

【发布时间】：2015-08-18 11:55:30

【问题描述】：

这是我在使用 AFNetworking 时如何显示进度条的代码，它运行良好。

现在，我的问题是我想在标签中设置进度视图的下载状态（如 inetger 值 45%，完成后状态已完成），那么我如何使用 AFNetworking 将其存档？ **

已编辑： 在下面的代码中，它将图像保存在文档目录中，但它采用“建议名称”作为文件，而不是自定义名称。现在我的问题是，当图像完全保存到文档目录中时，我有它的路径，如何使用该路径在图像视图中显示该图像？ 如果有人知道，请帮助我。

**

#import "ViewController.h"
#import "AFNetworking/AFNetworking.h"
#import "UIKit+AFNetworking/UIKit+AFNetworking.h"

#define URL @"https://secure.static.tumblr.com/6f8f2414ccc2def5e14e54b485dc07b5/8z4dq98/m0pn2d66g/tumblr_static_644cca222811a9dd32a6ecba52dfa1172.jpg"
@interface ViewController ()

@end

@implementation ViewController

- (void)viewDidLoad 
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.



- (IBAction)ActionPerform:(UIButton *)sender


    NSURLSessionConfiguration *configuration = [NSURLSessionConfiguration defaultSessionConfiguration];

    AFURLSessionManager *manager = [[AFURLSessionManager alloc] initWithSessionConfiguration:configuration];

    NSURL *strURL = [NSURL URLWithString:URL];
    NSURLRequest *request = [NSURLRequest requestWithURL:strURL];

    NSURLSessionDownloadTask *downloadTask = [manager downloadTaskWithRequest:request progress:nil destination:^NSURL *(NSURL *targetPath, NSURLResponse *response)
         

                NSURL *documentsDirectoryURL = [[NSFileManager defaultManager] URLForDirectory:NSDocumentDirectory inDomain:NSUserDomainMask appropriateForURL:nil create:NO error:nil];


                return [documentsDirectoryURL URLByAppendingPathComponent:[response suggestedFilename]];
         completionHandler:^(NSURLResponse *response, NSURL *filePath, NSError *error)
        
             NSLog(@"File downloaded to: %@", filePath);
        ];

    [self.ProgressView setProgressWithDownloadProgressOfTask:downloadTask animated:YES];
    [downloadTask resume];

@end

这是完整的答案：

#import "ViewController.h"
#import "secondViewController.h"

#define URL @"https://upload.wikimedia.org/wikipedia/commons/e/ec/USA-NYC-American_Museum_of_Natural_History.JPG"

@interface ViewController ()

@end

@implementation ViewController

- (void)viewDidLoad

    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.

    self.progressBar.hidden = YES ;
    self.lblProgressStatus.hidden = YES;


- (void)didReceiveMemoryWarning 
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.


- (IBAction)Action:(UIButton *)sender

    self.progressBar.hidden = NO ;
    self.lblProgressStatus.hidden = NO ;
    self.ActionDownload.enabled = NO ;

    NSURLSessionConfiguration *configuration = [NSURLSessionConfiguration defaultSessionConfiguration];
    AFURLSessionManager *manager = [[AFURLSessionManager alloc] initWithSessionConfiguration:configuration];

    NSURL *strURL = [NSURL URLWithString:URL];
    NSURLRequest *request = [NSURLRequest requestWithURL:strURL];

    NSProgress *progress;

    NSURLSessionDownloadTask *downloadTask = [manager downloadTaskWithRequest:request progress:&progress destination:^NSURL *(NSURL *targetPath, NSURLResponse *response)
        
                NSURL *documentsDirectoryURL = [[NSFileManager defaultManager] URLForDirectory:NSDocumentDirectory inDomain:NSUserDomainMask appropriateForURL:nil create:NO error:nil];
                return [documentsDirectoryURL URLByAppendingPathComponent:[response suggestedFilename]];
        
        completionHandler:^(NSURLResponse *response, NSURL *filePath, NSError *error)
        
                [self.progressBar setHidden:YES];
                self.lblProgressStatus.text = @"Download completed" ;
                NSLog(@"File downloaded to: %@", filePath);

                NSString * strTemp = [NSString stringWithFormat:@"%@", filePath];
                NSArray *components = [strTemp componentsSeparatedByString:@"/"];
                id obj = [components lastObject];
                NSLog(@"%@", obj);

            NSString *docPath = [NSSearchPathForDirectoriesInDomains (NSDocumentDirectory,NSUserDomainMask, YES) objectAtIndex:0];
            NSString *strFilePath = [NSString stringWithFormat:@"%@/%@",docPath, obj];

            BOOL fileExists=[[NSFileManager defaultManager] fileExistsAtPath:strFilePath];

            if (!fileExists)
            
                NSLog(@"File Not Found");
            
            else
            
                UIImage * image = [UIImage imageWithContentsOfFile:strFilePath];
                self.imageView.image = image ;
            
            [progress removeObserver:self forKeyPath:@"fractionCompleted" context:NULL];

        ];

    [self.progressBar setProgressWithDownloadProgressOfTask:downloadTask animated:YES];
    [downloadTask resume];

    [progress addObserver:self
               forKeyPath:NSStringFromSelector(@selector(fractionCompleted))                  options:NSKeyValueObservingOptionNew
                  context:NULL];



- (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary *)change context:(void *)context

    if ([keyPath isEqualToString:@"fractionCompleted"])
    
        NSProgress *progress = (NSProgress *)object;
        int temp = progress.fractionCompleted * 100 ;
       // NSLog(@"%d", temp);
       NSString * strTemp = @"%";

        dispatch_async(dispatch_get_main_queue(), ^
            // Update the UI
            self.lblProgressStatus.text = [NSString stringWithFormat:@"%d %@", temp, strTemp];
        );
    
    else
    
        [super observeValueForKeyPath:keyPath ofObject:object change:change context:context];
    

@end

【参考方案1】：

更多详情见https://***.com/a/19380812/5235106

这就是答案

- (IBAction)ActionPerform:(UIButton *)sender
    
    NSURLSessionConfiguration *configuration = [NSURLSessionConfiguration defaultSessionConfiguration];    
    AFURLSessionManager *manager = [[AFURLSessionManager alloc] initWithSessionConfiguration:configuration];    
    NSURL *strURL = [NSURL URLWithString:URL];
    NSURLRequest *request = [NSURLRequest requestWithURL:strURL];    
    NSProgress *progress;
    NSURLSessionDownloadTask *downloadTask = [manager downloadTaskWithRequest:request progress:&progress destination:^NSURL *(NSURL *targetPath, NSURLResponse *response)
             
                NSURL *documentsDirectoryURL = [[NSFileManager defaultManager] URLForDirectory:NSDocumentDirectory inDomain:NSUserDomainMask appropriateForURL:nil create:NO error:nil];    
                return [documentsDirectoryURL URLByAppendingPathComponent:[response suggestedFilename]];
         completionHandler:^(NSURLResponse *response, NSURL *filePath, NSError *error)
        
             NSLog(@"File downloaded to: %@", filePath);
        ];    
    [self.ProgressView setProgressWithDownloadProgressOfTask:downloadTask animated:YES];
    [downloadTask resume];
    [progress addObserver:self
        forKeyPath:@"fractionCompleted"
           options:NSKeyValueObservingOptionNew
           context:NULL];

- (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary *)change context:(void *)context

    if ([keyPath isEqualToString:@"fractionCompleted"]) 
        NSProgress *progress = (NSProgress *)object;
        // update the label text use progress
     else 
        [super observeValueForKeyPath:keyPath ofObject:object change:change context:context];
    

@end

【讨论】：

为什么进度条不流畅，第一次表现像向上，而不是向后运行，第二次运行流畅。我有多个图像