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  • 动态计算UITableViewCell高度<进阶>

    @property (nonatomic, strong) UITableViewCell *prototypeCell;
    
    //注册Nib
    UINib *cellNib = [UINib nibWithNibName:@"NLGC" bundle:nil];
    [self.tableView registerNib:cellNib forCellReuseIdentifier:@"NLGC"];
    self.prototypeCell  = [self.tableView dequeueReusableCellWithIdentifier:@"NLGC"];
    
    //CellForIndexPath
    - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
    {
        NLGC *cell = [self.tableView dequeueReusableCellWithIdentifier:@"NLGC"];
        cell.t.text = [self.tableData objectAtIndex:indexPath.row];
        return cell;
    }
    
    - (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath 
    {
        NLGC *cell = (NLGC *)self.prototypeCell;
        cell.t.text = [self.tableData objectAtIndex:indexPath.row];
        CGSize size = [cell.contentView systemLayoutSizeFittingSize:UILayoutFittingCompressedSize];
        NSLog(@"h=%f", size.height + 1);
        return 1  + size.height;
    }
    

      若文本控件是textView则要运用到sizeToFit

    - (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath 
    {
    NLGC *cell = (NLGC*)self.prototypeCell; 
    cell.t.text
    = [self.tableData objectAtIndex:indexPath.row];
    CGSize size
    = [cell.contentView systemLayoutSizeFittingSize:UILayoutFittingCompressedSize];
    CGSize textViewSize
    = [cell.t sizeThatFits:CGSizeMake(cell.t.frame.size.width, FLT_MAX)];
    CGFloat h
    = size.height + textViewSize.height; h = h > 89 ? h : 89; //89是图片显示的最低高度, 见xib
    NSLog(@"h=%f", h);
    return 1 + h;
    }

    Manual Layout

    - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
    {
        C3 *cell = [self.tableView dequeueReusableCellWithIdentifier:@"C3"];
        cell.t.text = [self.tableData objectAtIndex:indexPath.row];
        [cell.t sizeToFit];
        return cell;
    }
    
    - (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath {
        C3 *cell = (C3 *)self.prototypeCell;
        NSString *str = [self.tableData objectAtIndex:indexPath.row];
        cell.t.text = str;
        CGSize s = [str calculateSize:CGSizeMake(cell.t.frame.size.width, FLT_MAX) font:cell.t.font];
        CGFloat defaultHeight = cell.contentView.frame.size.height;
        CGFloat height = s.height > defaultHeight ? s.height : defaultHeight;
        NSLog(@"h=%f", height);
        return 1  + height;
    }
    
    - (CGSize)calculateSize:(CGSize)size font:(UIFont *)font 
    {
        CGSize expectedLabelSize = CGSizeZero;
    
        if ([[[UIDevice currentDevice] systemVersion] floatValue] >= 7) {
            NSMutableParagraphStyle *paragraphStyle = [[NSMutableParagraphStyle alloc] init];
            paragraphStyle.lineBreakMode = NSLineBreakByWordWrapping;
            NSDictionary *attributes = @{NSFontAttributeName:font, NSParagraphStyleAttributeName:paragraphStyle.copy};
    
            expectedLabelSize = [self boundingRectWithSize:size options:NSStringDrawingUsesLineFragmentOrigin attributes:attributes context:nil].size;
        }
        else {
            expectedLabelSize = [self sizeWithFont:font
                                           constrainedToSize:size
                                               lineBreakMode:NSLineBreakByWordWrapping];
        }
    
        return CGSizeMake(ceil(expectedLabelSize.width), ceil(expectedLabelSize.height));
    }
    

      

    如有疑问,共同探讨,共同进步。
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  • 原文地址:https://www.cnblogs.com/nielsen/p/6144262.html
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