Ios 滚动时TableView UILabel对齐方式发生更改

Ios 滚动时TableView UILabel对齐方式发生更改,ios,objective-c,uitableview,uilabel,Ios,Objective C,Uitableview,Uilabel,我有一个TableView和3个UILabel:标题、作者姓名和类别,还有一个UIImage。所有单元格应与此布局相似: 正确的单元格布局: 当应用程序因某种原因启动时,某些单元格的标题UILabel对齐方式与实际不符: 在滚动表视图几次后,这些单元格以正确的对齐方式结束。我不太清楚这是什么原因造成的 我已经创建了一个自定义的TableView单元格类(如下所示) CustomTableViewCell.h @interface CustomTableViewCell : UITable

我有一个
TableView
和3个
UILabel
:标题、作者姓名和类别,还有一个
UIImage
。所有单元格应与此布局相似:

正确的单元格布局:

当应用程序因某种原因启动时,某些单元格的标题
UILabel
对齐方式与实际不符:

在滚动
表视图几次后,这些单元格以正确的对齐方式结束。我不太清楚这是什么原因造成的

我已经创建了一个自定义的TableView单元格类(如下所示)

CustomTableViewCell.h

@interface CustomTableViewCell : UITableViewCell
@property (nonatomic, weak) IBOutlet UIImageView *image;
@property (nonatomic, weak) IBOutlet UILabel *titleLabel;
@property (nonatomic, weak) IBOutlet UILabel *authorLabel;
@property (nonatomic, weak) IBOutlet UILabel *categoryLabel;
@end
CustomTableViewCell.m

@implementation CustomTableViewCell

- (id)initWithStyle:(UITableViewCellStyle)style reuseIdentifier:(NSString *)reuseIdentifier
{
    self = [super initWithStyle:style reuseIdentifier:reuseIdentifier];

    if (self) {
        // Initialization code
    }
    return self;
}

- (void)awakeFromNib
{
   // Initialization code
}

- (void)setSelected:(BOOL)selected animated:(BOOL)animated
{
    [super setSelected:selected animated:animated];

    // Configure the view for the selected state
}

- (void)layoutSubviews
{
    [super layoutSubviews];
    [self.contentView layoutIfNeeded];
    self.titleLabel.preferredMaxLayoutWidth = CGRectGetWidth(self.titleLabel.frame);
    [self.titleLabel sizeToFit];
    [self.titleLabel setNumberOfLines:0];
}

@end
这就是该类在
ViewController
中的实现方式:

@interface CurrentIssueViewController () {
    CurrentIssueModel *_currentIssueModel;
    Article *_selectedArticle;
}

@end

@implementation CurrentIssueViewController

static NSString *cellIdentifier = @"BasicCell";
UIActivityIndicatorView *activityView;
//@synthesize _feedItems;

- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
    self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
    if (self) {
        // Custom initialization
    }
    return self;
}

- (void)viewDidLoad
{
    [super viewDidLoad];


    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(didChangePreferredContentSize:)name:UIContentSizeCategoryDidChangeNotification object:nil];

    // Create array object and assign it to _feedItems variable
    self._feedItems = [[NSArray alloc] init];

    // Create new HomeModel object and assign it to _homeModel variable
    _currentIssueModel = [[CurrentIssueModel alloc] init];

    // Set this view controller object as the delegate for the home model object
    _currentIssueModel.delegate = self;

    // Call the download items method of the home model object
    [_currentIssueModel downloadItems];
}

- (void)dealloc
{
    [[NSNotificationCenter defaultCenter] removeObserver:self name:UIContentSizeCategoryDidChangeNotification object:nil];
}

- (void)didChangePreferredContentSize:(NSNotification *)notification
{
    [self.tableView reloadData];
}

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

-(void)itemsDownloaded:(NSArray *)items
{
    // This delegate method will get called when the items are finished downloading

    // Set the downloaded items to the array
    self._feedItems = items;

    [activityView stopAnimating];

    // Reload the table view
    [self.tableView reloadData];
}

#pragma mark Table View Delegate Methods

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
    // Return the number of feed items (initially 0)
    return self._feedItems.count;
}

/* ================================================== */

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:cellIdentifier forIndexPath:indexPath];
    [self configureCell:cell forRowAtIndexPath:indexPath];
    return cell;
}

- (void)configureCell:(UITableViewCell *)cell forRowAtIndexPath:(NSIndexPath *)indexPath
{
    if ([cell isKindOfClass:[CustomTableViewCell class]])
    {
        CustomTableViewCell *textCell = (CustomTableViewCell *)cell;

        Article *article_item = self._feedItems[indexPath.row];

        NSString *fulltitle = article_item.Title;

        if (article_item.Subtitle != nil && article_item.Subtitle.length != 0) {
            fulltitle = [fulltitle stringByAppendingString:@": "];
            fulltitle = [fulltitle stringByAppendingString:article_item.Subtitle];
        }
        textCell.titleLabel.text = fulltitle;

        if ([article_item.Author isEqualToString:@"accountant"]) {
            textCell.authorLabel.text = @"";
        }
        else {
            textCell.authorLabel.text = article_item.Author;
        }

        textCell.categoryLabel.text = article_item.Cat_Name;

        textCell.titleLabel.numberOfLines = 0;
        textCell.titleLabel.font = [UIFont fontWithName:@"Arial" size:12.0f];

        textCell.authorLabel.font = [UIFont fontWithName:@"Arial" size:10.0f];
        textCell.categoryLabel.font = [UIFont fontWithName:@"Arial" size:10.0f];
        textCell.categoryLabel.textAlignment = NSTextAlignmentRight;

        NSURL *url;

        if ([article_item.ImageUrl length] != 0) {
            url = [NSURL URLWithString:article_item.ImageUrl];
        }
        else {
            url = [NSURL URLWithString:@"imageurl"];
        }

        [textCell.image sd_setImageWithURL:url placeholderImage:[UIImage imageNamed:@"default_image.jpg"]];
    }
}

- (CustomTableViewCell *)prototypeCell
{
    if (!_prototypeCell)
    {
        _prototypeCell = [self.tableView dequeueReusableCellWithIdentifier:cellIdentifier];
    }
    return _prototypeCell;
}

- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
    [self configureCell:self.prototypeCell forRowAtIndexPath:indexPath];

    self.prototypeCell.bounds = CGRectMake(0.0f, 0.0f, CGRectGetWidth(self.tableView.bounds), CGRectGetHeight(self.prototypeCell.bounds));

    [self.prototypeCell layoutIfNeeded];

    CGSize size = [self.prototypeCell.contentView systemLayoutSizeFittingSize:UILayoutFittingCompressedSize];
    return size.height+1;
}

/* ================================================== */

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
    // Set selected article to var
    _selectedArticle = self._feedItems[indexPath.row];
    [self performSegueWithIdentifier:@"detailSegue" sender:self];

}

#pragma mark Segue

- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
    // Get reference to the destination view controller
    ArticleViewController *articleVC = segue.destinationViewController;

    // Set the property to the selected article so when the view for
    // detail view controller loads, it can access that property to get the feeditem obj
    articleVC.selectedArticle = _selectedArticle;
}

@end
我想这与
forrowatinexpath
有关,但我真的不知道问题出在哪里

更新:


我注意到标题
UILabel
还有另一个问题。每当您选择一个单元格时,请在另一个
ViewController
中查看文章,然后返回
UITableView
标题标签位于
左中
而不是
左上
。再次滚动后,标题标签将调整到正确的位置。

您已经为NIB/情节提要选择了自动布局,但没有向单元格添加任何约束。向单元格添加布局约束。有一个很好的答案详细地解释了这一点:

检查我的答案,并使用“-(UITableViewCell*)tableView:(UITableView*))tableView cell for row索引路径:(nsindepath*)indexPath`方法并根据该答案初始化自定义单元格,然后执行以下操作可能会帮助您感谢您的评论…我已经在使用
cellforrowatinexpath
,我已经用该函数更新了我的问题。我会试试你的建议。然后尝试把FoRoWaveRexXPATH的所有代码放在CyfFoRoWordRexPoad方法中作为Pr.My的答案。同样的事情发生在一些单元格上,你应该给你的标签添加一些约束。这正是约束用于此的原因,约束未正确设置。这让我意识到了问题所在:,还有你的链接。再次感谢。