步骤一、TableViewCell中使用Autolayout
要点：Cell的高度必须在Constraints中指明，但不能定死，需要让内部由内容决定高度的View决定动态高度。
如UILabel设置numberOfLines为0，设置好左右约束和上下相对位置的约束后就可以让Label的内在高度尺寸约束决定Label的高，即可让系统推断出整个cell的高。
步骤二、在Controller中设置TableView的属性
要点：
self.tableView.estimatedRowHeight = 54;//54为你估算的每个单元格的平均行高，方便系统计算滚动条大小等动作
self.tableView.rowHeight = UITableViewAutomaticDimension;//实际值为-1,让系统自动计算Cell的行高。
样例代码：(使用Masonry第三方Autolayout库)
Cell：
1: //
2: // NewsCell.h
3: // M04P20-新闻
4: //
5: // Created by 张泽阳 on 4/26/15.
6: // Copyright (c) 2015 张泽阳. All rights reserved.
7: //
8: 9: #import <UIKit/UIKit.h> 10: @class News;
11: @interface NewsCell : UITableViewCell
12: 13: @property (nonatomic,strong) UILabel* newsTitleLabel; 14: @property (nonatomic,strong) UILabel* newsAuthorLabel; 15: @property (nonatomic,strong) UILabel* newsCommentsLabel; 16: @property (nonatomic,strong) UIImageView* pictureImageView; 17: -(void)setContentData:(News*)news;
18: +(instancetype)newsCellWithTableView:(UITableView*)tableView; 19: @end 20: 21: 22: //
23: // NewsCell.m
24: // M04P20-新闻
25: //
26: // Created by 张泽阳 on 4/26/15.
27: // Copyright (c) 2015 张泽阳. All rights reserved.
28: //
29: 30: #import "NewsCell.h"
31: #import "News.h"
32: #import "Masonry.h"
33: @implementation NewsCell 34: 35: /**
36: * 懒加载
37: */
38: -(UILabel *)newsCommentsLabel{ 39: if (!_newsCommentsLabel) {
40: _newsCommentsLabel = [[UILabel alloc]init]; 41: } 42: return _newsCommentsLabel;
43: } 44: -(UILabel *)newsTitleLabel{ 45: if (!_newsTitleLabel) {
46: _newsTitleLabel = [[UILabel alloc]init]; 47: 48: } 49: return _newsTitleLabel;
50: } 51: -(UILabel *)newsAuthorLabel{ 52: if (!_newsAuthorLabel) {
53: _newsAuthorLabel = [[UILabel alloc]init]; 54: [self.contentView addSubview:_newsAuthorLabel]; 55: } 56: return _newsAuthorLabel;
57: } 58: -(UIImageView *)pictureImageView{ 59: if (!_pictureImageView) {
60: _pictureImageView = [[UIImageView alloc]init]; 61: } 62: return _pictureImageView;
63: } 64: /**
65: * 便利构造器
66: */
67: +(instancetype)newsCellWithTableView:(UITableView *)tableView{ 68: static NSString* ID = @"news";
69: NewsCell* cell = [tableView dequeueReusableCellWithIdentifier:ID]; 70: if (!cell) {
71: cell = [[NewsCell alloc]initWIthTableView:tableView andID:ID]; 72: } 73: 74: [cell setNeedsLayout]; 75: [cell layoutIfNeeded]; 76: return cell;
77: } 78: /**
79: * init中设置相对固定的数据
80: *
81: */
82: -(instancetype)initWIthTableView:(UITableView*)tablview andID:(NSString*)ID{ 83: // static NSString* ID = @"news";
84: self = [super initWithStyle:UITableViewCellStyleDefault reuseIdentifier:ID];//别忘了super init
85: [self.contentView addSubview:self.newsTitleLabel]; 86: [self.contentView addSubview:self.newsAuthorLabel]; 87: [self.contentView addSubview:self.pictureImageView]; 88: [self.contentView addSubview:self.newsCommentsLabel]; 89: 90: self.newsCommentsLabel.textColor = [UIColor grayColor]; 91: self.newsCommentsLabel.font = [UIFont systemFontOfSize:12]; 92: [self.newsCommentsLabel setHighlightedTextColor:[UIColor whiteColor]]; 93: self.newsAuthorLabel.textColor = [UIColor grayColor]; 94: self.newsAuthorLabel.font = [UIFont systemFontOfSize:12]; 95: [self.newsAuthorLabel setHighlightedTextColor:[UIColor whiteColor]]; 96: 97: self.newsTitleLabel.font = [UIFont boldSystemFontOfSize:15]; 98: self.newsTitleLabel.numberOfLines = 0; 99: 100: [self.newsTitleLabel setHighlightedTextColor:[UIColor whiteColor]]; 101: self.pictureImageView.contentMode = UIViewContentModeScaleAspectFit; 102: 103: return self;
104: } 105: /**
106: * 设置相对动态的数据
107: */
108: -(void)setContentData:(News *)news{
109: self.newsTitleLabel.text = news.title; 110: self.newsAuthorLabel.text = news.author; 111: self.newsCommentsLabel.text = [NSString stringWithFormat:@"评论：%d",news.comments];
112: self.pictureImageView.image = [UIImage imageNamed:news.icon]; 113: } 114: /**
115: * 设置布局 记得调用super
116: */
117: -(void)layoutSubviews{
118: [super layoutSubviews]; 119: [self.newsTitleLabel mas_makeConstraints:^(MASConstraintMaker *make){ 120: make.top.equalTo(self.contentView.mas_top).mas_offset(8); ///offset???
121: make.left.equalTo(self.contentView.mas_left).mas_offset(8); 122: make.right.equalTo(self.pictureImageView.mas_left).mas_offset(-8); 123: }]; 124: 125: [self.newsAuthorLabel mas_makeConstraints:^(MASConstraintMaker *make){ 126: make.left.equalTo(self.newsTitleLabel); 127: make.top.greaterThanOrEqualTo(self.newsTitleLabel.mas_bottom).mas_offset(8); 128: make.bottom.equalTo(self.contentView.mas_bottom).mas_offset(-8); 129: }]; 130: 131: [self.newsCommentsLabel mas_makeConstraints:^(MASConstraintMaker *make){ 132: make.top.equalTo(self.newsAuthorLabel.mas_top); 133: make.right.equalTo(self.pictureImageView.mas_left).mas_offset(-8); 134: }]; 135: 136: [self.pictureImageView mas_makeConstraints:^(MASConstraintMaker *make){ 137: make.top.equalTo(self.contentView.mas_top).mas_offset(8); 138: make.right.equalTo(self.contentView.mas_right).mas_offset(-8); 139: make.bottom.equalTo(self.contentView.mas_bottom).mas_offset(-8); 140: make.width.mas_equalTo(120); 141: }]; 142: } 143: /**
144: * 单元格被选中/取消选中时的表现
145: */
146: -(void)setSelected:(BOOL)selected animated:(BOOL)animated{
147: [super setSelected:selected animated:animated]; 148: // self.newsTitleLabel.textColor = selected?([UIColor whiteColor]):([UIColor blackColor]);
149: // self.newsAuthorLabel.textColor = selected?([UIColor whiteColor]):([UIColor blackColor]);
150: // self.newsCommentsLabel.textColor = selected?([UIColor whiteColor]):([UIColor blackColor]);
151: } 152: @end
Controller中：
1: //
2: // ViewController.h
3: // M04P20-新闻
4: //
5: // Created by 张泽阳 on 4/26/15.
6: // Copyright (c) 2015 张泽阳. All rights reserved.
7: //
8: 9: #import <UIKit/UIKit.h> 10: 11: @interface ViewController : UIViewController
12: @property (nonatomic,strong) NSArray* newses; 13: 14: @end 15: 16: 17: //
18: // ViewController.m
19: // M04P20-新闻
20: //
21: // Created by 张泽阳 on 4/26/15.
22: // Copyright (c) 2015 张泽阳. All rights reserved.
23: //
24: 25: #import "ViewController.h"
26: #import "News.h"
27: #import "NewsCell.h"
28: #import "NSObject+NSObject_ZZYMODEL.h"
29: @interface ViewController ()<UITableViewDelegate,UITableViewDataSource>
30: @property (weak, nonatomic) IBOutlet UITableView *tableView; 31: 32: @end 33: 34: @implementation ViewController 35: -(NSArray *)newses{ 36: if (!_newses) {
37: _newses = [News modelArrayWithFilename:@"news.plist"];
38: } 39: return _newses;
40: } 41: - (void)viewDidLoad {
42: [super viewDidLoad]; 43: self.tableView.estimatedRowHeight = 54; 44: self.tableView.rowHeight = UITableViewAutomaticDimension; 45: [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(orientationDidRotate) name:UIApplicationDidChangeStatusBarOrientationNotification object:nil];
46: } 47: -(BOOL)prefersStatusBarHidden{ 48: return YES;
49: } 50: -(void)orientationDidRotate{
51: [self.tableView reloadData]; 52: } 53: -(NSInteger)numberOfSectionsInTableView:(UITableView *)tableView{ 54: return 1;
55: } 56: 57: -(NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section{ 58: return self.newses.count;
59: } 60: 61: -(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath{ 62: NewsCell* cell = [NewsCell newsCellWithTableView:tableView]; 63: [cell setContentData:self.newses[indexPath.row]]; 64: 65: 66: return cell;
67: 68: } 69: 70: 71: 72: 73: @end
参考连接：
http://www.mgenware.com/blog/?p=507
http://blog.163.com/china_uv/blog/static/1171372672014111681232340/