2015-07-11 76 views
0

我正在尝试创建一个自定义的UITableViewCell,并且存在具有适当高度的单元格框架问题。这很麻烦,因为iPhone 4s/5s运行iOS 8.4的单元尺寸正确,但运行相同操作系统的iPhone 6/6 +的单元尺寸却不正确。UITableViewCell高度不正确,sizeToFit尺寸不正确

混沌发生在messageLabel上,呼叫sizeToFit。有些标签几乎看起来在下面有额外的空白行,但显然没有单元格所显示的那么高。

下面是自定义单元格。看起来会引起麻烦的标签是messageLabel。要查看帧的标签,let borders = true

// 
// NotesTableViewCell.swift 
// urchin 
// 
// Created by Ethan Look on 6/17/15. 
// Copyright (c) 2015 Tidepool. All rights reserved. 
// 

import Foundation 
import UIKit 

let noteCellHeight: CGFloat = 128 
let noteCellInset: CGFloat = 16 
let labelSpacing: CGFloat = 6 

class NoteCell: UITableViewCell { 

    let borders = false 

    var cellHeight: CGFloat = CGFloat() 

    let usernameLabel: UILabel = UILabel() 
    let timedateLabel: UILabel = UILabel() 
    var messageLabel: UILabel = UILabel() 

    func configureWithNote(note: Note) { 

     usernameLabel.text = note.user!.fullName 
     usernameLabel.font = UIFont(name: "OpenSans-Bold", size: 17.5)! 
     usernameLabel.textColor = UIColor.blackColor() 
     usernameLabel.sizeToFit() 
     let usernameX = noteCellInset 
     let usernameY = noteCellInset 
     usernameLabel.frame.origin = CGPoint(x: usernameX, y: usernameY) 

     let dateFormatter = NSDateFormatter() 
     dateFormatter.dateFormat = "EEEE M.d.yy h:mm a" 
     var dateString = dateFormatter.stringFromDate(note.timestamp) 
     dateString = dateString.stringByReplacingOccurrencesOfString("PM", withString: "pm", options: NSStringCompareOptions.LiteralSearch, range: nil) 
     dateString = dateString.stringByReplacingOccurrencesOfString("AM", withString: "am", options: NSStringCompareOptions.LiteralSearch, range: nil) 
     timedateLabel.text = dateString 
     timedateLabel.font = UIFont(name: "OpenSans", size: 12.5)! 
     timedateLabel.textColor = UIColor.blackColor() 
     timedateLabel.sizeToFit() 
     let timedateX = contentView.frame.width - (noteCellInset + timedateLabel.frame.width) 
     let timedateY = usernameLabel.frame.midY - timedateLabel.frame.height/2 
     timedateLabel.frame.origin = CGPoint(x: timedateX, y: timedateY) 

     messageLabel.frame.size = CGSize(width: contentView.frame.width - 2 * noteCellInset, height: CGFloat.max) 
     let hashtagBolder = HashtagBolder() 
     let attributedText = hashtagBolder.boldHashtags(note.messagetext) 
     messageLabel.attributedText = attributedText 
     messageLabel.adjustsFontSizeToFitWidth = false 
     messageLabel.lineBreakMode = NSLineBreakMode.ByWordWrapping 
     messageLabel.numberOfLines = 0 
     messageLabel.sizeToFit() 
     let messageX = noteCellInset 
     let messageY = usernameLabel.frame.maxY + 2 * labelSpacing 
     messageLabel.frame.origin = CGPoint(x: messageX, y: messageY) 

     contentView.addSubview(usernameLabel) 
     contentView.addSubview(timedateLabel) 
     contentView.addSubview(messageLabel) 

     cellHeight = noteCellInset + usernameLabel.frame.height + 2 * labelSpacing + messageLabel.frame.height + noteCellInset 

     if (borders) { 
      usernameLabel.layer.borderWidth = 1 
      usernameLabel.layer.borderColor = UIColor.redColor().CGColor 

      timedateLabel.layer.borderWidth = 1 
      timedateLabel.layer.borderColor = UIColor.redColor().CGColor 

      messageLabel.layer.borderWidth = 1 
      messageLabel.layer.borderColor = UIColor.redColor().CGColor 

      self.contentView.layer.borderWidth = 1 
      self.contentView.layer.borderColor = UIColor.blueColor().CGColor 
     } 

     self.contentView.frame.size = CGSize(width: self.contentView.frame.width, height: cellHeight) 
    } 
} 

而且heightForRowAtIndexPath

func tableView(tableView: UITableView, heightForRowAtIndexPath indexPath: NSIndexPath) -> CGFloat { 
     let cell = NoteCell(style: .Default, reuseIdentifier: nil) 
     cell.configureWithNote(notes[indexPath.row]) 
     return cell.cellHeight 
} 

该项目是开源的,on Github,可以随意克隆库,并检查了所有的代码自己。

谢谢!

回答

0

而是在heightForRowAtIndexPath:创建一个全新的细胞,我简单地创建确定单元格高度的UI元素(usernameLabel和messageLabel),大小它们,然后做一个简单:

检查它计算以确定细胞高度。

通过这样做,我从来没有创建一个新的细胞,后来出队。

func tableView(tableView: UITableView, heightForRowAtIndexPath indexPath: NSIndexPath) -> CGFloat { 

    let usernameLabel = UILabel(frame: CGRectZero) 
    usernameLabel.font = UIFont(name: "OpenSans-Bold", size: 17.5)! 
    usernameLabel.text = notes[indexPath.row].user!.fullName 
    usernameLabel.sizeToFit() 

    let messageLabel = UILabel(frame: CGRect(x: 0, y: 0, width: self.view.frame.width - 2*noteCellInset, height: CGFloat.max)) 
    let hashtagBolder = HashtagBolder() 
    let attributedText = hashtagBolder.boldHashtags(notes[indexPath.row].messagetext) 
    messageLabel.attributedText = attributedText 
    messageLabel.adjustsFontSizeToFitWidth = false 
    messageLabel.lineBreakMode = NSLineBreakMode.ByWordWrapping 
    messageLabel.numberOfLines = 0 
    messageLabel.sizeToFit() 

    let cellHeight = noteCellInset + usernameLabel.frame.height + 2 * labelSpacing + messageLabel.frame.height + noteCellInset 

    return cellHeight 
} 
0

不幸的是,你不能这样做,因为首先调用tableView(_:heightForRowAtIndexPath),并且返回的值用于创建将在tableView(_:cellForRowAtIndexPath)中出队的单元格。单元格不能设置其自己的大小,因为在它可以这样做的时候(例如awakeFromNibprepareForResuse),表格视图将已经具有它的高度值。我已经使用了一些令人吃惊的解决方法,但是使用自定义表格视图单元更容易。与sizeToFit适当 http://www.appcoda.com/self-sizing-cells/