用Model来计算cell的高度

来源地址：http://www.cnblogs.com/YouXianMing/p/4214469.html

效果：



将计算cell高度的方法直接移植到Model当中，初始化的瞬间就计算好了高度，非常好用！

源码：

Model

//
//  Model.h
//
//  Copyright (c) 2014年 Y.X. All rights reserved.
//

#import <Foundation/Foundation.h>
#import <UIKit/UIKit.h>

@interface Model : NSObject

@property (nonatomic, strong) NSString       *info;
@property (nonatomic, strong) NSString       *subInfo;
@property (nonatomic, strong) NSString       *details;

@property (nonatomic, assign) CGFloat         infoHeight;
@property (nonatomic, assign) CGFloat         subInfoHeight;
@property (nonatomic, assign) CGFloat         detailsHeight;
@property (nonatomic, assign) CGFloat         totalHeight;

- (void)setValue:(id)value forUndefinedKey:(NSString *)key;
- (instancetype)initWithDictionary:(NSDictionary *)dictionary;

@end

//
//  Model.m
//
//  Copyright (c) 2014年 Y.X. All rights reserved.
//

#import "Model.h"

@implementation Model

- (void)setValue:(id)value forUndefinedKey:(NSString *)key {

}

- (void)setValue:(id)value forKey:(NSString *)key {
if ([value isKindOfClass:[NSNull class]]) {
return;
}

[super setValue:value forKey:key];
}

- (instancetype)initWithDictionary:(NSDictionary *)dictionary {
self = [super init];
if (self) {
if ([dictionary isKindOfClass:[NSDictionary class]]) {
[self setValuesForKeysWithDictionary:dictionary];
}
}

self.infoHeight    = [Model heightWithString:self.info    LabelFont:[UIFont boldSystemFontOfSize:18.f] withLabelWidth:300];
self.subInfoHeight = [Model heightWithString:self.subInfo LabelFont:[UIFont systemFontOfSize:14.f] withLabelWidth:300];
self.detailsHeight = [Model heightWithString:self.details LabelFont:[UIFont italicSystemFontOfSize:16.f] withLabelWidth:300];
self.totalHeight   = self.infoHeight + self.subInfoHeight + self.detailsHeight;

return self;
}

#pragma mark - 计算文本高度
+ (CGFloat)heightWithString:(NSString *)string LabelFont:(UIFont *)font withLabelWidth:(CGFloat)width {
CGFloat height = 0;

if (string.length == 0) {
height = 0;
} else {

// 字体
NSDictionary *attribute = @{NSFontAttributeName: [UIFont systemFontOfSize:18.f]};
if (font) {
attribute = @{NSFontAttributeName: font};
}

// 尺寸
CGSize retSize = [string boundingRectWithSize:CGSizeMake(width, MAXFLOAT)
options:
NSStringDrawingTruncatesLastVisibleLine |
NSStringDrawingUsesLineFragmentOrigin |
NSStringDrawingUsesFontLeading
attributes:attribute
context:nil].size;

height = retSize.height;
}

return height;
}

@end

ModelCell

//
//  ModelCell.h
//  HeightModel
//
//  Created by YouXianMing on 15/1/10.
//  Copyright (c) 2015年 YouXianMing. All rights reserved.
//

#import <UIKit/UIKit.h>

@interface ModelCell : UITableViewCell

@property (nonatomic, strong) UILabel   *info;
@property (nonatomic, strong) UILabel   *subInfo;
@property (nonatomic, strong) UILabel   *details;

- (void)accessData:(id)model;

@end

//
//  ModelCell.m
//  HeightModel
//
//  Created by YouXianMing on 15/1/10.
//  Copyright (c) 2015年 YouXianMing. All rights reserved.
//

#import "ModelCell.h"
#import "Model.h"
#import "UIView+SetRect.h"

@implementation ModelCell

- (instancetype)initWithStyle:(UITableViewCellStyle)style reuseIdentifier:(NSString *)reuseIdentifier {
if (self = [super initWithStyle:style reuseIdentifier:reuseIdentifier]) {

_info                  = [[UILabel alloc] initWithFrame:CGRectMake(10, 10, 300, 20)];
_info.numberOfLines    = 0;
_info.font             = [UIFont boldSystemFontOfSize:18.f];
_info.textColor        = [UIColor blackColor];
[self addSubview:_info];

_subInfo               = [[UILabel alloc] initWithFrame:CGRectMake(10, 10, 300, 20)];
_subInfo.numberOfLines = 0;
_subInfo.font          = [UIFont systemFontOfSize:14.f];
_subInfo.textColor     = [UIColor grayColor];
[self addSubview:_subInfo];

_details               = [[UILabel alloc] initWithFrame:CGRectMake(10, 10, 300, 20)];
_details.numberOfLines = 0;
_details.font          = [UIFont italicSystemFontOfSize:16.f];
_details.textColor     = [UIColor redColor];
[self addSubview:_details];

}

return self;
}

- (void)accessData:(id)model {
if ([model isKindOfClass:[Model class]]) {
Model *dataModel = model;

_info.text   = dataModel.info;
_info.frame  = CGRectMake(10, 10, 300, 20);
[_info sizeToFit];

_subInfo.text  = dataModel.subInfo;
_subInfo.frame = CGRectMake(10, _info.height + 10, 300, 20);
[_subInfo sizeToFit];

_details.text  = dataModel.details;
_details.frame = CGRectMake(10, _info.height + _subInfo.height + 10, 300, 20);
[_details sizeToFit];
}
}

@end

工具类 UIView+SetRect

//
//  UIView+SetRect.h
//  TestPch
//
//  Created by YouXianMing on 14-9-26.
//  Copyright (c) 2014年 YouXianMing. All rights reserved.
//

#import <UIKit/UIKit.h>

@interface UIView (SetRect)

// Frame
@property (nonatomic) CGPoint viewOrigin;
@property (nonatomic) CGSize  viewSize;

// Frame Origin
@property (nonatomic) CGFloat x;
@property (nonatomic) CGFloat y;

// Frame Size
@property (nonatomic) CGFloat width;
@property (nonatomic) CGFloat height;

// Frame Borders
@property (nonatomic) CGFloat top;
@property (nonatomic) CGFloat left;
@property (nonatomic) CGFloat bottom;
@property (nonatomic) CGFloat right;

// Center Point
#if !IS_IOS_DEVICE
@property (nonatomic) CGPoint center;
#endif
@property (nonatomic) CGFloat centerX;
@property (nonatomic) CGFloat centerY;

// Middle Point
@property (nonatomic, readonly) CGPoint middlePoint;
@property (nonatomic, readonly) CGFloat middleX;
@property (nonatomic, readonly) CGFloat middleY;

@end

//
//  UIView+SetRect.m
//  TestPch
//
//  Created by YouXianMing on 14-9-26.
//  Copyright (c) 2014年 YouXianMing. All rights reserved.
//

#import "UIView+SetRect.h"

@implementation UIView (SetRect)

#pragma mark Frame

- (CGPoint)viewOrigin
{
return self.frame.origin;
}

- (void)setViewOrigin:(CGPoint)newOrigin
{
CGRect newFrame = self.frame;
newFrame.origin = newOrigin;
self.frame = newFrame;
}

- (CGSize)viewSize
{
return self.frame.size;
}

- (void)setViewSize:(CGSize)newSize
{
CGRect newFrame = self.frame;
newFrame.size = newSize;
self.frame = newFrame;
}

#pragma mark Frame Origin

- (CGFloat)x
{
return self.frame.origin.x;
}

- (void)setX:(CGFloat)newX
{
CGRect newFrame = self.frame;
newFrame.origin.x = newX;
self.frame = newFrame;
}

- (CGFloat)y
{
return self.frame.origin.y;
}

- (void)setY:(CGFloat)newY
{
CGRect newFrame = self.frame;
newFrame.origin.y = newY;
self.frame = newFrame;
}

#pragma mark Frame Size

- (CGFloat)height
{
return self.frame.size.height;
}

- (void)setHeight:(CGFloat)newHeight
{
CGRect newFrame = self.frame;
newFrame.size.height = newHeight;
self.frame = newFrame;
}

- (CGFloat)width
{
return self.frame.size.width;
}

- (void)setWidth:(CGFloat)newWidth
{
CGRect newFrame = self.frame;
newFrame.size.width = newWidth;
self.frame = newFrame;
}

#pragma mark Frame Borders

- (CGFloat)left
{
return self.x;
}

- (void)setLeft:(CGFloat)left
{
self.x = left;
}

- (CGFloat)right
{
return self.frame.origin.x + self.frame.size.width;
}

- (void)setRight:(CGFloat)right
{
self.x = right - self.width;
}

- (CGFloat)top
{
return self.y;
}

- (void)setTop:(CGFloat)top
{
self.y = top;
}

- (CGFloat)bottom
{
return self.frame.origin.y + self.frame.size.height;
}

- (void)setBottom:(CGFloat)bottom
{
self.y = bottom - self.height;
}

#pragma mark Center Point

#if !IS_IOS_DEVICE
- (CGPoint)center
{
return CGPointMake(self.left + self.middleX, self.top + self.middleY);
}

- (void)setCenter:(CGPoint)newCenter
{
self.left = newCenter.x - self.middleX;
self.top = newCenter.y - self.middleY;
}
#endif

- (CGFloat)centerX
{
return self.center.x;
}

- (void)setCenterX:(CGFloat)newCenterX
{
self.center = CGPointMake(newCenterX, self.center.y);
}

- (CGFloat)centerY
{
return self.center.y;
}

- (void)setCenterY:(CGFloat)newCenterY
{
self.center = CGPointMake(self.center.x, newCenterY);
}

#pragma mark Middle Point

- (CGPoint)middlePoint
{
return CGPointMake(self.middleX, self.middleY);
}

- (CGFloat)middleX
{
return self.width / 2;
}

- (CGFloat)middleY
{
return self.height / 2;
}

@end

控制器

//
//  ViewController.m
//  HeightModel
//
//  Created by YouXianMing on 15/1/10.
//  Copyright (c) 2015年 YouXianMing. All rights reserved.
//

#import "ViewController.h"
#import "Model.h"
#import "ModelCell.h"

static NSString *modelCellFlag = @"ModelCell.h";

@interface ViewController ()<UITableViewDataSource, UITableViewDelegate>

@property (nonatomic, strong) UITableView     *tableView;
@property (nonatomic, strong) NSMutableArray  *dataModelArray;

@end

@implementation ViewController

- (void)viewDidLoad {
[super viewDidLoad];

// 数据源
self.dataModelArray = [NSMutableArray array];
[self.dataModelArray addObject:[[Model alloc] initWithDictionary:@{@"info"   : @"P.K.",
@"subInfo": @"逝者如斯，而未尝往也；盈虚者如彼，而卒莫消长也。盖将自其变者而观之，则天地曾不能以一瞬；自其不变者而观之，则物与我皆无尽也。",
@"details": @""}]];
[self.dataModelArray addObject:[[Model alloc] initWithDictionary:@{@"info"   : @"YouXianMing",
@"subInfo": @"合抱之木，生于毫末；九层之合，起于垒土；千里之行，始于足下。",
@"details": @"精简计算UITableView文本高度"}]];
[self.dataModelArray addObject:[[Model alloc] initWithDictionary:@{@"info"   : @"Q.L.",
@"subInfo": @"",
@"details": @""}]];
[self.dataModelArray addObject:[[Model alloc] initWithDictionary:@{@"info"   : @"",
@"subInfo": @"",
@"details": @"This is a test ok ?"}]];
[self.dataModelArray addObject:[[Model alloc] initWithDictionary:@{@"info"   : @"",
@"subInfo": @"YouXianMing 한 iOS 개발 엔지니어, 사랑 사랑 기술, 생활, 기꺼이 바치다, 좋아하는 게임만 좋아하는 것을 좋아하는 사람이다 가축, 학습, 확신하다 천도 보수 자주!",
@"details": @""}]];
[self.dataModelArray addObject:[[Model alloc] initWithDictionary:@{@"info"   : @"遊賢明はiOS開発エンジニア、愛する技術で、生活を愛し、献身、ゲームが好き、好きなものを食べて、美食愛好家、天道酬勤を学ぶことが好きで、信じ！",
@"subInfo": @"",
@"details": @"YouXianMing copyright."}]];
[self.dataModelArray addObject:[[Model alloc] initWithDictionary:@{@"info"   : @"ว่ายน้ำที่ชาญฉลาดเป็น iOS วิศวกรพัฒนาเทคโนโลยีและรักชีวิตรักและทุ่มเทและชอบเล่นเกมชอบกินอะไรดีเลยชอบการเรียนรู้และเชื่อว่าไม่มีอะไรเลย",
@"subInfo": @"Nager sage est un ingénieur, le développement de la technologie iOS amour, de l'amour de la vie, de dévouement, de jouer le jeu, aime manger, c'est un bon à rien, comme l'apprentissage, convaincu que Tiandaochouqin!",
@"details": @"entwickler, liebe, Leben, liebe, hingabe, Wie Spiele, der Gern Essen, ist ein Nahrungsmittel, Wie Lernen, Davon überzeugt, dass Gott"}]];

// tableView
self.tableView = [[UITableView alloc] initWithFrame:self.view.bounds
style:UITableViewStylePlain];
self.tableView.delegate   = self;
self.tableView.dataSource = self;
[self.tableView registerClass:[ModelCell class] forCellReuseIdentifier:modelCellFlag];
[self.view addSubview:self.tableView];

}

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
return self.dataModelArray.count;
}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
ModelCell *cell     = [tableView dequeueReusableCellWithIdentifier:modelCellFlag];
cell.selectionStyle = UITableViewCellSelectionStyleNone;
[cell accessData:self.dataModelArray[indexPath.row]];

return cell;
}

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

Model *model = self.dataModelArray[indexPath.row];
return 20 + model.totalHeight;
}

@end

一些需要注意的地方：