从 URL 将图像推送到 UITableViewCell 中

Question

我使用以下代码从站点下载 RSS 提要。我想在 feeds 中添加一张图片以获得更多 'modern' 界面，因为此代码仅下载新闻标题。我不知道该怎么做。

提示？

    @interface MasterTableViewController () {

    NSXMLParser *parser;
    NSMutableArray *feeds;
    NSMutableDictionary *item;
    NSMutableString *title;
    NSMutableString *link;
    NSString *element;
}

@end

@implementation MasterTableViewController

@synthesize recipe = _recipe;
@synthesize tableView =_tableView;


- (void)awakeFromNib {
    [super awakeFromNib];
}

- (void)viewDidLoad {
    [super viewDidLoad];
    feeds = [[NSMutableArray alloc] init];
    NSURL *url = [NSURL URLWithString:[_recipe stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding]];
    parser = [[NSXMLParser alloc] initWithContentsOfURL:url];
    [parser setDelegate:self];
    [parser setShouldResolveExternalEntities:NO];
    [parser parse];
    [self.navigationController.navigationBar setTitleTextAttributes:
     @{NSForegroundColorAttributeName:[UIColor whiteColor]}];
}


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

#pragma mark - Table view data source

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView {
    return 1;
}

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {

    return feeds.count;
}


- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:@"Cell" forIndexPath:indexPath];
    cell.textLabel.text = [[feeds objectAtIndex:indexPath.row] objectForKey: @"title"];
    return cell;
}

- (void)parser:(NSXMLParser *)parser didStartElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qName attributes:(NSDictionary<NSString *,NSString *> *)attributeDict {
    element = elementName;

    if ([element isEqualToString:@"item"]) {

        item    = [[NSMutableDictionary alloc] init];
        title   = [[NSMutableString alloc] init];
        link    = [[NSMutableString alloc] init];
    }
}

- (void)parser:(NSXMLParser *)parser didEndElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qName {
    if ([elementName isEqualToString:@"item"]) {
        [item setObject:title forKey:@"title"];
        [item setObject:link forKey:@"link"];
        [feeds addObject:[item copy]];
    }
}

-(void)parser:(NSXMLParser *)parser foundCharacters:(NSString *)string {
    if ([element isEqualToString:@"title"]) {
        [title appendString:string];
    } else if ([element isEqualToString:@"link"]) {
        [link appendString:string];
    }
}

- (void)parserDidEndDocument:(NSXMLParser *)parser {
    [self.tableView reloadData];
}


#pragma mark - Navigation


- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {
    if ([[segue identifier] isEqualToString:@"showDetail"]) {
        NSIndexPath *indexPath = [self.tableView indexPathForSelectedRow];
        NSString *string = [feeds[indexPath.row] objectForKey:@"link"];
        [[segue destinationViewController] setUrl:string];
    }
}

- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
    return 60;
}

@end

Answer 1

您可以在 cellForRowAtIndex 中使用 NSURLSession 来获取数据并将其显示在单元格背景中。

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:@"Cell" forIndexPath:indexPath];
cell.textLabel.text = [[feeds objectAtIndex:indexPath.row] objectForKey: @"title"];

NSError *error;
NSURLSessionConfiguration *configuration = [NSURLSessionConfiguration defaultSessionConfiguration];
NSURLSession *session = [NSURLSession sessionWithConfiguration:configuration delegate:self delegateQueue:nil];
NSURL *url = [NSURL URLWithString:[items objectAtIndex:indexPath.row]objectForKey:"link"]];
NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url
                                                   cachePolicy:NSURLRequestUseProtocolCachePolicy
                                               timeoutInterval:60.0];

[request setHTTPMethod:@"POST"];

NSURLSessionDataTask *postDataTask = [session dataTaskWithRequest:request completionHandler:^(NSData *data, NSURLResponse *response, NSError *error) {
    //data will return an imageData
    UIImage *image = [UIImage imageWithData:data];
    cell.backgroundImage = image;
}];

[postDataTask resume];
return cell;
}

从 URL 将图像推送到 UITableViewCell 中

Push image in UITableViewCell from URL

iphone

objective-c

uitableview

nsstring

ios