iphone - 具有重叠单元格的自定义单元格

Question

我正在使用方法 cellForRowAtIndexPath 绘制带有 2 个标签的单元格。当我重复使用一个单元格时，我之前在该单元格中的标签不会被删除，所以我得到两个重叠的标签，因为我正在重复使用一个单元格。这很奇怪，因为只有标签标题重叠，其他的则没有。

所以我为解决这个问题所做的是，我总是创建一个新的单元格。哪个不合适但解决了问题......任何人都有类似的错误并设法修复它？因为我刚刚做了一个解决方法...

//Desenhado por codigo
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
UITableViewCell *cell;
UILabel *label = nil;
UILabel *label2 = nil;    
UIColor *green = [UIColor colorWithRed:0 green: 0.77 blue:0 alpha:1];

cell = [tableView dequeueReusableCellWithIdentifier:@"Cell"];
//    if (cell == nil)
{
    cell = [[[UITableViewCell alloc] initWithFrame:CGRectZero reuseIdentifier:@"Cell"] autorelease];

    //Descrição
    label = [[UILabel alloc] initWithFrame:CGRectZero];
    [label setLineBreakMode:UILineBreakModeWordWrap];
    [label setMinimumFontSize:FONT_SIZE];
    [label setNumberOfLines:0];
    [label setFont:[UIFont systemFontOfSize:FONT_SIZE]];
    [label setFont:[UIFont fontWithName:@"HelveticaNeue-CondensedBold" size:14.0]];        
    [label setTag:1];
    [label setTextColor:green];     
    [label setBackgroundColor:[UIColor clearColor]];      
    label.backgroundColor = [UIColor colorWithPatternImage:[UIImage imageNamed:@"barra_cinza_lista.png"]];        
    [[cell contentView] addSubview:label];

    label2 = [[UILabel alloc] initWithFrame:CGRectZero];
    [label2 setLineBreakMode:UILineBreakModeWordWrap];
    [label2 setMinimumFontSize:FONT_SIZE];
    [label2 setNumberOfLines:0];
    [label2 setFont:[UIFont systemFontOfSize:FONT_SIZE]];
    [label2 setFont:[UIFont fontWithName:@"HelveticaNeue-CondensedBold" size:14.0]];        
    [label2 setTag:2];
    [label2 setTextColor:[UIColor whiteColor]];     
    [label2 setBackgroundColor:[UIColor clearColor]];

    [[cell contentView] addSubview:label2];  
}

NSString *text = [self getTableViewRow:tableView index:indexPath]; 

NSString *title = @"    %@";

if(tableView == myTableView1) 
    title = [NSString stringWithFormat:title, [_titlesResults objectAtIndex:indexPath.row]];
else 
    title = [NSString stringWithFormat:title, [_titlesVision objectAtIndex:indexPath.row]]; 

CGFloat widthMax = CELL_CONTENT_WIDTH - (CELL_CONTENT_MARGIN * 2);

CGSize constraint = CGSizeMake(widthMax, 20000.0f); //Tamanho máximo permitido de largura e altura
CGSize size1 = [title sizeWithFont:[UIFont systemFontOfSize:FONT_SIZE] constrainedToSize:constraint lineBreakMode:UILineBreakModeWordWrap];     //Tamanho ocupado pelas letras
CGSize size2 = [text sizeWithFont:[UIFont systemFontOfSize:FONT_SIZE] constrainedToSize:constraint lineBreakMode:UILineBreakModeWordWrap];     //Tamanho ocupado pelas letras

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

if (!label2)
    label2 = (UILabel*)[cell viewWithTag:2];    

[label setText:title];
[label setFrame:CGRectMake(0, 0, 320, MAX(size1.height, 44.0f))];    
[label2 setText:text];
[label2 setFrame:CGRectMake(CELL_CONTENT_MARGIN, 3 * CELL_CONTENT_MARGIN + size1.height, widthMax, MAX(size2.height, 44.0f))];    

return cell;
}

Answer 1

在该方法的开头，枚举[cell.contentView subviews] 中的所有UIView 对象并删除它们，如下所示:

for (UIView *subview in [cell.contentView subviews]) {
    [subview removeFromSuperview];
}

这是有效的，因为所有 UI 元素都继承自 UIView，因此可以像它们一样被删除。