I am using a custom UITableViewCell which has some labels, buttons and image views to be displayed. There is one label in the cell whose text is a NSString object and the length of string could be variable. Due to this, I cannot set a constant height to the cell in the UITableView's heightForCellAtIndex method. The cell's height depends on the label's height which can be determined using the NSString's sizeWithFont method. I tried using it, but it looks like I'm going wrong somewhere. How can it be fixed?

下面是用于初始化单元格的代码。

if (self = [super initWithFrame:frame reuseIdentifier:reuseIdentifier])
{
    self.selectionStyle = UITableViewCellSelectionStyleNone;
    UIImage *image = [UIImage imageNamed:@"dot.png"];
    imageView = [[UIImageView alloc] initWithImage:image];
    imageView.frame = CGRectMake(45.0,10.0,10,10);

    headingTxt = [[UILabel alloc] initWithFrame:   CGRectMake(60.0,0.0,150.0,post_hdg_ht)];
    [headingTxt setContentMode: UIViewContentModeCenter];
    headingTxt.text = postData.user_f_name;
    headingTxt.font = [UIFont boldSystemFontOfSize:13];
    headingTxt.textAlignment = UITextAlignmentLeft;
    headingTxt.textColor = [UIColor blackColor];

    dateTxt = [[UILabel alloc] initWithFrame:CGRectMake(55.0,23.0,150.0,post_date_ht)];
    dateTxt.text = postData.created_dtm;
    dateTxt.font = [UIFont italicSystemFontOfSize:11];
    dateTxt.textAlignment = UITextAlignmentLeft;
    dateTxt.textColor = [UIColor grayColor];

    NSString * text1 = postData.post_body;
    NSLog(@"text length = %d",[text1 length]);
    CGRect bounds = [UIScreen mainScreen].bounds;
    CGFloat tableViewWidth;
    CGFloat width = 0;
    tableViewWidth = bounds.size.width/2;
    width = tableViewWidth - 40; //fudge factor
    //CGSize textSize = {width, 20000.0f}; //width and height of text area
    CGSize textSize = {245.0, 20000.0f}; //width and height of text area
    CGSize size1 = [text1 sizeWithFont:[UIFont systemFontOfSize:11.0f]
                        constrainedToSize:textSize lineBreakMode:UILineBreakModeWordWrap];

    CGFloat ht = MAX(size1.height, 28);
    textView = [[UILabel alloc] initWithFrame:CGRectMake(55.0,42.0,245.0,ht)];
    textView.text = postData.post_body;
    textView.font = [UIFont systemFontOfSize:11];
    textView.textAlignment = UITextAlignmentLeft;
    textView.textColor = [UIColor blackColor];
    textView.lineBreakMode = UILineBreakModeWordWrap;
    textView.numberOfLines = 3;
    textView.autoresizesSubviews = YES;

    [self.contentView addSubview:imageView];
    [self.contentView addSubview:textView];
    [self.contentView addSubview:webView];
    [self.contentView addSubview:dateTxt];
    [self.contentView addSubview:headingTxt];
    [self.contentView sizeToFit];

    [imageView release];
    [textView release];
    [webView release];
    [dateTxt release];
    [headingTxt release];
}

这个标签的高度和宽度都出了问题:

textView = [[UILabel alloc] initWithFrame:CGRectMake(55.0,42.0,245.0,ht)];

当前回答

你的UITableViewDelegate应该实现tableView: highightforrowatindexpath:

objective - c

- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
    return [indexPath row] * 20;
}

斯威夫特5

func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {
    return indexPath.row * 20
}

你可能会想使用NSString的sizeWithFont:constrainedToSize:lineBreakMode:方法来计算你的行高,而不是在indexPath:)上执行一些愚蠢的数学运算

其他回答

你的UITableViewDelegate应该实现tableView: highightforrowatindexpath:

objective - c

- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
    return [indexPath row] * 20;
}

斯威夫特5

func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {
    return indexPath.row * 20
}

你可能会想使用NSString的sizeWithFont:constrainedToSize:lineBreakMode:方法来计算你的行高,而不是在indexPath:)上执行一些愚蠢的数学运算

- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath;
{
    CGSize constraintSize = {245.0, 20000}
    CGSize neededSize = [ yourText sizeWithFont:[UIfont systemFontOfSize:14.0f] constrainedToSize:constraintSize  lineBreakMode:UILineBreakModeCharacterWrap]
if ( neededSize.height <= 18) 

   return 45
else return neededSize.height + 45 
//18 is the size of your text with the requested font (systemFontOfSize 14). if you change fonts you have a different number to use  
// 45 is what is required to have a nice cell as the neededSize.height is the "text"'s height only
//not the cell.

}

要有动态单元格高度作为标签的文本增加,你首先需要计算高度,文本将使用- highightforrowatindexpath委托方法,并返回其他标签的高度,图像(文本的最大高度+其他静态组件的高度),并在单元格创建中使用相同的高度。

#define FONT_SIZE 14.0f
#define CELL_CONTENT_WIDTH 300.0f  
#define CELL_CONTENT_MARGIN 10.0f

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

    if (indexPath.row == 2) {  // the cell you want to be dynamic

        NSString *text = dynamic text for your label;

        CGSize constraint = CGSizeMake(CELL_CONTENT_WIDTH - (CELL_CONTENT_MARGIN * 2), 20000.0f);
        CGSize size = [text sizeWithFont:[UIFont systemFontOfSize:FONT_SIZE] constrainedToSize:constraint lineBreakMode:UILineBreakModeWordWrap];

        CGFloat height = MAX(size.height, 44.0f);

        return height + (CELL_CONTENT_MARGIN * 2);
    }
    else {
        return 44; // return normal cell height
    }
}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {

    static NSString *CellIdentifier = @"Cell";

    UILabel *label;

    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];

    if (cell == nil) {
        cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleValue1 reuseIdentifier:CellIdentifier] ;
    }

    label = [[UILabel alloc] initWithFrame:CGRectMake(10, 5, 280, 34)];

    [label setNumberOfLines:2];

    label.backgroundColor = [UIColor clearColor];

    [label setFont:[UIFont systemFontOfSize:FONT_SIZE]];

    label.adjustsFontSizeToFitWidth = NO;

    [[cell contentView] addSubview:label];


    NSString *text = dynamic text fro your label;

    [label setText:text];

    if (indexPath.row == 2) {// the cell which needs to be dynamic 

        [label setNumberOfLines:0];

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

        CGSize size = [text sizeWithFont:[UIFont systemFontOfSize:FONT_SIZE] constrainedToSize:constraint lineBreakMode:UILineBreakModeWordWrap];

        [label setFrame:CGRectMake(CELL_CONTENT_MARGIN, CELL_CONTENT_MARGIN, CELL_CONTENT_WIDTH - (CELL_CONTENT_MARGIN * 2), MAX(size.height, 44.0f))];

    }
    return  cell;
}
#define FONT_SIZE 14.0f
#define CELL_CONTENT_WIDTH 300.0f
#define CELL_CONTENT_MARGIN 10.0f

- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath      *)indexPath;
{
   /// Here you can set also height according to your section and row
   if(indexPath.section==0 && indexPath.row==0)
   {
     text=@"pass here your dynamic data";

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

     CGSize size = [text sizeWithFont:[UIFont systemFontOfSize:FONT_SIZE]      constrainedToSize:constraint lineBreakMode:UILineBreakModeWordWrap];

     CGFloat height = MAX(size.height, 44.0f);

     return height + (CELL_CONTENT_MARGIN * 2);
   }
   else
   {
      return 44;
   }
}

- (UITableViewCell *)tableView:(UITableView *)tv cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    UITableViewCell *cell;
    UILabel *label = nil;

    cell = [tv dequeueReusableCellWithIdentifier:@"Cell"];
    if (cell == nil)
    {
       cell = [[UITableViewCell alloc] initWithFrame:CGRectZero reuseIdentifier:@"Cell"];
    }
    ********Here you can set also height according to your section and row*********
    if(indexPath.section==0 && indexPath.row==0)
    {
        label = [[UILabel alloc] initWithFrame:CGRectZero];
        [label setLineBreakMode:UILineBreakModeWordWrap];
        [label setMinimumFontSize:FONT_SIZE];
        [label setNumberOfLines:0];
        label.backgroundColor=[UIColor clearColor];
        [label setFont:[UIFont systemFontOfSize:FONT_SIZE]];
        [label setTag:1];

        // NSString *text1 =[NSString stringWithFormat:@"%@",text];

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

        CGSize size = [text sizeWithFont:[UIFont systemFontOfSize:FONT_SIZE] constrainedToSize:constraint lineBreakMode:UILineBreakModeWordWrap];

        if (!label)
        label = (UILabel*)[cell viewWithTag:1];


        label.text=[NSString stringWithFormat:@"%@",text];
        [label setFrame:CGRectMake(CELL_CONTENT_MARGIN, CELL_CONTENT_MARGIN, CELL_CONTENT_WIDTH          - (CELL_CONTENT_MARGIN * 2), MAX(size.height, 44.0f))];
        [cell.contentView addSubview:label];
    }
return cell;
}

感谢所有关于这个主题的文章,这里有一些非常有用的方法来调整UITableViewCell的rowHeight。

以下是其他人提供的一些概念的汇编,这些概念在为iPhone和iPad开发游戏时非常有用。您还可以访问不同的部分,并根据视图的大小进行调整。

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

if (UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiomPad)
{
    int cellHeight = 0;

    if ([indexPath section] == 0) 
    {
        cellHeight = 16;
        settingsTable.rowHeight = cellHeight;
    }
    else if ([indexPath section] == 1)
    {
        cellHeight = 20;
        settingsTable.rowHeight = cellHeight;
    }

    return cellHeight;
}
else
{
    int cellHeight = 0;

    if ([indexPath section] == 0) 
    {
        cellHeight = 24;
        settingsTable.rowHeight = cellHeight;
    }
    else if ([indexPath section] == 1)
    {
        cellHeight = 40;
        settingsTable.rowHeight = cellHeight;
    }

    return cellHeight;
}
return 0;
}