Question

我正在将JSON字符串解析为自定义表格视图单元格。如何调整标签的高度以适应内容文本，还可以调整单元格的大小以适应内容。

代码：

#import "DEMOSecondViewController.h"
#import "DEMONavigationController.h"
#import "PostsObject.h"
#import "RNBlurModalView.h"
#import "AFNetworking.h"

@interface DEMOSecondViewController ()

@end

@implementation DEMOSecondViewController
@synthesize tableView = _tableView, activityIndicatorView = _activityIndicatorView, movies = _movies;

- (void)viewDidLoad
{
    [super viewDidLoad];
    self.title = @"iCelebri.com";
    self.navigationItem.leftBarButtonItem = [[UIBarButtonItem alloc] initWithTitle:@"Menu"
                                                                             style:UIBarButtonItemStylePlain
                                                                            target:(DEMONavigationController *)self.navigationController
                                                                            action:@selector(showMenu)];

    self.tableView.separatorColor = [UIColor clearColor];

    // Setting Up Activity Indicator View
    self.activityIndicatorView = [[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleGray];
    self.activityIndicatorView.hidesWhenStopped = YES;
    self.activityIndicatorView.center = self.view.center;
    [self.view addSubview:self.activityIndicatorView];
    [self.activityIndicatorView startAnimating];
    self.tableView.separatorColor = [UIColor clearColor];

    // Initializing Data Source
    self.movies = [[NSArray alloc] init];

    [self makeConnection];

}

-(void)makeConnection {
    _url = [[NSURL alloc] initWithString:@"my-site.com/json.php?name=Name"];
    NSURLRequest *request = [[NSURLRequest alloc] initWithURL:_url];

    AFJSONRequestOperation *operation = [AFJSONRequestOperation JSONRequestOperationWithRequest:request success:^(NSURLRequest *request, NSHTTPURLResponse *response, id JSON) {
        self.movies = JSON;
        [self.activityIndicatorView stopAnimating];
        [self.tableView reloadData];

    } failure:^(NSURLRequest *request, NSHTTPURLResponse *response, NSError *error, id JSON) {
        NSLog(@"Request Failed with Error: %@, %@", error, error.userInfo);
    }];

    [operation start];
}

// Table View Data Source Methods
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
    if (self.movies && self.movies.count) {
        return self.movies.count;
    } else {
        return 0;
    }
}

- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
    return 124;
}

- (void)tableView:(UITableView *)tableView
  willDisplayCell:(UITableViewCell *)cell
forRowAtIndexPath:(NSIndexPath *)indexPath
{
    [cell setBackgroundColor:[UIColor clearColor]];
}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
    static NSString *simpleTableIdentifier = @"PostsObject";

    PostsObject *cell = (PostsObject *)[tableView dequeueReusableCellWithIdentifier:simpleTableIdentifier];
    if (cell == nil)
    {
        NSArray *nib = [[NSBundle mainBundle] loadNibNamed:@"PostsObject" owner:self options:nil];
        cell = [nib objectAtIndex:0];
        cell.selectionStyle = UITableViewCellSelectionStyleNone;
        UIImageView *imageView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"background.png"]];

        self.tableView.backgroundView = imageView;
    }

    NSDictionary *movie = [self.movies objectAtIndex:indexPath.row];
    cell.title.text = [movie objectForKey:@"message"];
    cell.published.text = [movie objectForKey:@"published"];

    return cell;
}


@end

所以我希望单元格调整为标题标签和文本标签的大小 “消息”：[movie objectForKey:@"message"];

我该怎么做？

Answer 1

这是根据每个indexPath的文本长度调整单元格高度的完整代码：

.h文件：

#import <UIKit/UIKit.h>

@interface ViewController : UIViewController <UITableViewDataSource, UITableViewDelegate> {
    IBOutlet UITableView *_tableView;
    UIActivityIndicatorView *_activityIndicatorView;
    NSArray *_movies;
    CGFloat cellTextWidth;
    CGFloat cellHeightExceptText;
}
@property (nonatomic, retain) UIFont *fontForCellText;
@property (nonatomic, retain) UITableView *tableView;
@property (nonatomic, retain) UIActivityIndicatorView *activityIndicatorView;
@property (nonatomic, retain) NSArray *movies;

@end

.m文件：

#import "ViewController.h"
#import "AFNetworking.h"
#import "ParseFeedCell.h"

@interface ViewController ()

@end

@implementation ViewController
@synthesize tableView = _tableView, activityIndicatorView = _activityIndicatorView, movies = _movies;
@synthesize fontForCellText;

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

    NSArray *nib = [[NSBundle mainBundle] loadNibNamed:@"ParseFeedCell" owner:self options:nil];
    ParseFeedCell *cell = [nib objectAtIndex:0];
    fontForCellText = cell.title.font;
    cellTextWidth = cell.title.frame.size.width;
    cellHeightExceptText = cell.frame.size.height - cell.title.frame.size.height;

    [self.navigationController setNavigationBarHidden:YES];

    self.tableView.separatorColor = [UIColor clearColor];

    // Setting Up Activity Indicator View
    self.activityIndicatorView = [[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleGray];
    self.activityIndicatorView.hidesWhenStopped = YES;
    self.activityIndicatorView.center = self.view.center;
    [self.view addSubview:self.activityIndicatorView];
    [self.activityIndicatorView startAnimating];
    self.tableView.separatorColor = [UIColor clearColor];

    // Initializing Data Source
    //self.movies = [[NSArray alloc] init];

    NSURL *url = [[NSURL alloc] initWithString:@"your-website.com/json_file?name=Name"];
    NSURLRequest *request = [[NSURLRequest alloc] initWithURL:url];

    AFJSONRequestOperation *operation = [AFJSONRequestOperation JSONRequestOperationWithRequest:request success:^(NSURLRequest *request, NSHTTPURLResponse *response, id JSON) {
        self.movies = [[NSArray alloc] initWithArray:JSON];
        [self.activityIndicatorView stopAnimating];
        [self.tableView reloadData];

    } failure:^(NSURLRequest *request, NSHTTPURLResponse *response, NSError *error, id JSON) {
        NSLog(@"Request Failed with Error: %@, %@", error, error.userInfo);
    }];

    [operation start];
}

// Table View Data Source Methods
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
    if (self.movies && self.movies.count) {
        return self.movies.count;
    } else {
        return 0;
    }
}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
    static NSString *simpleTableIdentifier = @"ParseFeedCell";

    ParseFeedCell *cell = (ParseFeedCell *)[tableView dequeueReusableCellWithIdentifier:simpleTableIdentifier];
    if (cell == nil)
    {
        NSArray *nib = [[NSBundle mainBundle] loadNibNamed:@"ParseFeedCell" owner:self options:nil];
        cell = [nib objectAtIndex:0];
        cell.selectionStyle = UITableViewCellSelectionStyleNone;

    }

    NSDictionary *movie = [self.movies objectAtIndex:indexPath.row];
    NSString *strText = [movie objectForKey:@"message"];

    CGRect rect = cell.title.frame;
    rect.size.height = [self getHeightForText:strText];
    cell.title.frame = rect;
    cell.title.text = strText;
    cell.arrow.center = CGPointMake(cell.arrow.frame.origin.x, rect.origin.y + rect.size.height/2);
    cell.published.text = [movie objectForKey:@"published"];
    return cell;
}

- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
    NSDictionary *movie = [self.movies objectAtIndex:indexPath.row];
    NSString *strText = [movie objectForKey:@"message"];

    CGFloat cellHeight = cellHeightExceptText + [self getHeightForText:strText];

    return cellHeight;
}

- (CGFloat)getHeightForText:(NSString *)strText
{
    CGSize constraintSize = CGSizeMake(cellTextWidth, MAXFLOAT);
    CGSize labelSize = [strText sizeWithFont:fontForCellText constrainedToSize:constraintSize lineBreakMode:NSLineBreakByWordWrapping];
    NSLog(@"labelSize.height = %f",labelSize.height);
    return labelSize.height;
}

确保您的自定义单元格“ParseFeedCell”的Autolayout已关闭（未选中）：

Autolayout

同时将文本UILabel的行的数量更改为999999，因此不限于行。我相信通过一些研究，您可以找到一种方法来了解文本的行数，并以编程方式将行分配给UILabel。

Answer 2

将其用于动态大小的单元格：

首先定义以下内容：

#define FONT_SIZE 13.0f 
#define CELL_CONTENT_WIDTH 290.0f 
#define CELL_CONTENT_MARGIN 19.0f

实现以下帮助方法;

 -(CGSize)frameForText:(NSString*)text sizeWithFont:(UIFont*)font constrainedToSize:(CGSize)size  {

NSMutableParagraphStyle * paragraphStyle = [[NSMutableParagraphStyle defaultParagraphStyle] mutableCopy];
paragraphStyle.lineBreakMode = NSLineBreakByCharWrapping;

NSDictionary * attributes = @{NSFontAttributeName:font,
                              NSParagraphStyleAttributeName:paragraphStyle
                              };


CGRect textRect = [text boundingRectWithSize:size
                                     options:NSStringDrawingUsesLineFragmentOrigin
                                  attributes:attributes
                                     context:nil];


// This contains both height and width, but we really care about height.
return textRect.size;
}

在您的UITableViewDelegate高度方法中：

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

NSDictionary *movie = [self.movies objectAtIndex:indexPath.row];

        NSString *text = [movie objectForKey:@"message"];        

        CGSize constraint = CGSizeMake(CELL_CONTENT_WIDTH - (CELL_CONTENT_MARGIN * 2), 20000.0f);

        CGSize size = [self frameForText:text sizeWithFont:[UIFont systemFontOfSize:FONT_SIZE] constrainedToSize:constraint];

        CGFloat height = MAX(size.height, 14.0f);

        return height + CELL_CONTENT_MARGIN;


}

在UITableViews cellForRowAtIndexPath中设置框架和文字：

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
static NSString *simpleTableIdentifier = @"PostsObject";

PostsObject *cell = (PostsObject *)[tableView dequeueReusableCellWithIdentifier:simpleTableIdentifier];
if (cell == nil)
{
    NSArray *nib = [[NSBundle mainBundle] loadNibNamed:@"PostsObject" owner:self options:nil];
    cell = [nib objectAtIndex:0];
    cell.selectionStyle = UITableViewCellSelectionStyleNone;
    UIImageView *imageView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"background.png"]];

    self.tableView.backgroundView = imageView;
}

NSDictionary *movie = [self.movies objectAtIndex:indexPath.row];

NSString *text = [movie objectForKey:@"message"];


    CGSize constraint = CGSizeMake(CELL_CONTENT_WIDTH - (CELL_CONTENT_MARGIN * 2), 20000.0f);


    CGSize size = [self frameForText:text sizeWithFont:[UIFont systemFontOfSize:FONT_SIZE] constrainedToSize:constraint];

    cell.txtLabel.text = text;
    cell.txtLabel.frame = CGRectMake(CELL_CONTENT_MARGIN, CELL_CONTENT_MARGIN, CELL_CONTENT_WIDTH - (CELL_CONTENT_MARGIN * 2), MAX(size.height, 14.0f));

cell.published.text = [movie objectForKey:@"published"];

return cell;
}

Answer 3

如果您希望基于JSON的内容调整单元格大小，则必须更改以下方法：

- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
    return 124;
}

您将每个单元格的高度设置为124px。你应该做什么而不是它：

获取用。呈现的字符串的大小指定的约束。
重置包含字符串
返回正确的单元格大小的的tableView：heightForRowAtIndexPath：

希望它有所帮助！干杯

根据JSON文件中的内容文本，使用UILabel调整自定义单元格大小

3 个答案: