自动计算UITableViewCell高度2（CGRect约束）

1.先创建model

.h

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

@interface LBDNewMsgListModel : NSObject

@property (nonatomic, copy) NSString *activityId;
@property (nonatomic, copy) NSString *activityImg;
@property (nonatomic, copy) NSString *colorType;
@property (nonatomic, copy) NSString *content;
@property (nonatomic, copy) NSString *createdAt;
@property (nonatomic, copy) NSString *remark;
@property (nonatomic, copy) NSString *jump;
@property (nonatomic, copy) NSString *title;

@property (assign,nonatomic) CGFloat cellHeight; // cell的高度（在本model类中进行计算)

@end

.m

#import "LBDNewMsgListModel.h"
#import "LBDMsgCenterCell.h"

@interface LBDNewMsgListModel ()

@property (strong, nonatomic) LBDMsgCenterCell *cell;

@end

@implementation LBDNewMsgListModel

- (LBDMsgCenterCell *)cell
{

    if(!_cell){

        _cell = [[LBDMsgCenterCell alloc]init];
        _cell.model = self;
    }
    return _cell;
}

- (CGFloat)cellHeight
{
    if (_cellHeight == ) {

        _cellHeight = self.cell.cellHeight;
        self.cell = nil;
    }
    return _cellHeight;
}

2.自定义cell

.h

#import <UIKit/UIKit.h>
#import "LBDNewMsgListModel.h"

static NSString *cellID = @"LBDMsgCenterCell";

@protocol LBDMessageCenterCellDelagete <NSObject>

@optional

- (void)returnCellHeight:(CGFloat)height;

@end

@interface LBDMsgCenterCell : UITableViewCell

@property (nonatomic, strong) UILabel *msgDateLbl;
@property (nonatomic, strong) UIView *bgView;
@property (nonatomic, strong) UIView *topLineView;
@property (nonatomic, strong) UIImageView *msgImgView;
@property (nonatomic, strong) UILabel *titleLbl;
@property (nonatomic, strong) UILabel *orderNum;
@property (nonatomic, strong) UILabel *contentLbl;
@property (nonatomic, strong) UIView *lineView;
@property (nonatomic, strong) UILabel *lookLbl;

@property (nonatomic, strong) LBDNewMsgListModel *model;
+ (instancetype)cellWithTableView:(UITableView *)tableView;

@property (nonatomic, weak) id<LBDMessageCenterCellDelagete>delegate;

@property (assign,nonatomic) CGFloat cellHeight; // cell的高度

@end

.m

#import "LBDMsgCenterCell.h"
#import "LBDNewMsgListModel.h"
#import "NSString+Extension.h"

@implementation LBDMsgCenterCell

- (void)awakeFromNib {
    [super awakeFromNib];
    // Initialization code
}

+ (instancetype)cellWithTableView:(UITableView *)tableView {

    LBDMsgCenterCell *cell = [tableView dequeueReusableCellWithIdentifier:cellID];
    if (!cell) {

        cell = [[LBDMsgCenterCell alloc]initWithStyle:UITableViewCellStyleDefault reuseIdentifier:cellID];
    }

    cell.selectionStyle = UITableViewCellSelectionStyleNone;
    tableView.backgroundColor = [UIColor getColor:@"ececec"];
    cell.backgroundColor = [UIColor getColor:@"ececec"];

    return cell;
}

- (instancetype)initWithStyle:(UITableViewCellStyle)style reuseIdentifier:(NSString *)reuseIdentifier {

    if (self = [super initWithStyle:style reuseIdentifier:reuseIdentifier]) {

        [self drawCell];
    }
    return self;
}

- (void)setModel:(LBDNewMsgListModel *)model
{
    _model = model;

    if ([model.colorType isEqualToString:@""]) {

        _topLineView.hidden = NO;
        _msgImgView.hidden = YES;
        _topLineView.backgroundColor = [UIColor getColor:@"feb540"];
    } else if ([model.colorType isEqualToString:@""]) {

        _topLineView.hidden = NO;
        _msgImgView.hidden = YES;
        _topLineView.backgroundColor = [UIColor getColor:@"00ade5"];
    } else if ([model.colorType isEqualToString:@""]) {

        _topLineView.hidden = YES;
        _msgImgView.hidden = NO;

        [_msgImgView sd_setImageWithURL:[NSURL URLWithString:model.activityImg]];

    }

    if ([model.jump isEqualToString:@""]) {

        _lineView.hidden = YES;
        _lookLbl.hidden = YES;
    } else if ([model.jump isEqualToString:@""]) {

        _lineView.hidden = NO;
        _lookLbl.hidden = NO;
    }

    _msgDateLbl.text = [Tool dateStrConverWithDateStr:model.createdAt originalType:@"yyyyMMddHHmmss" type:@"yyyy/MM/dd HH:mm"];
    _titleLbl.text = model.title;
    _contentLbl.text = model.content;

    [self layoutIfNeeded];
    self.cellHeight = CGRectGetMaxY(_bgView.frame);

}

- (void)drawCell {

    _msgDateLbl = [[UILabel alloc] init];
    _msgDateLbl.text = @"2016/12/25 09:11";
    _msgDateLbl.font = FONT();
    _msgDateLbl.textColor = [UIColor getColor:@""];
    _msgDateLbl.textAlignment = NSTextAlignmentCenter;
    [self.contentView addSubview:_msgDateLbl];

    _bgView = [[UIView alloc] init];
    _bgView.backgroundColor = [UIColor whiteColor];
    _bgView.layer.masksToBounds = YES;
    _bgView.layer.cornerRadius = ;
    [self.contentView addSubview:_bgView];

    _msgImgView = [[UIImageView alloc] init];
    _msgImgView.hidden = YES;
    _msgImgView.contentMode = UIViewContentModeScaleAspectFit;
    [_bgView addSubview:_msgImgView];

    _topLineView = [[UIView alloc] init];
    _topLineView.hidden = YES;
    [_bgView addSubview:_topLineView];

    _titleLbl = [[UILabel alloc] init];
    _titleLbl.font = FONT();
    _titleLbl.numberOfLines = ;
    _titleLbl.textColor = [UIColor getColor:@""];
    [_bgView addSubview:_titleLbl];

    _contentLbl = [[UILabel alloc] init];
    _contentLbl.font = FONT();
    _contentLbl.numberOfLines = ;
    _contentLbl.textColor = [UIColor getColor:@""];
    [_bgView addSubview:_contentLbl];

    _lookLbl = [[UILabel alloc] init];
    _lookLbl.textAlignment = NSTextAlignmentRight;;
    _lookLbl.text = @"立即查看";
    _lookLbl.font = FONT();
    [_bgView addSubview:_lookLbl];

    _lineView = [[UIView alloc] init];
    _lineView.backgroundColor = [UIColor getColor:@"ececec"];
    [_bgView addSubview:_lineView];

}

- (void)layoutSubviews {
    [super layoutSubviews];

    _msgDateLbl.frame = CGRectMake(, , SCREEN_WIDTH, );

    _bgView.frame = CGRectMake(, CGRectGetMaxY(_msgDateLbl.frame), SCREEN_WIDTH - , );

    CGSize titleSize = [_model.title sizeWithFont:FONT() andMaxSize:CGSizeMake(SCREEN_WIDTH - , MAXFLOAT)];
    CGSize contentSize = [_model.content sizeWithFont:FONT() andMaxSize:CGSizeMake(SCREEN_WIDTH - , MAXFLOAT)];

    if ([_model.colorType isEqualToString:@""] || [_model.colorType isEqualToString:@""]) {

        _topLineView.frame = CGRectMake(, , SCREEN_WIDTH - , );
        _msgImgView.frame = CGRectZero;

        _titleLbl.frame = CGRectMake(, CGRectGetMaxY(_topLineView.frame) + , SCREEN_WIDTH - , titleSize.height);

    } else if ([_model.colorType isEqualToString:@""]) {

        _topLineView.frame = CGRectZero;
        _msgImgView.frame = CGRectMake(, , SCREEN_WIDTH - , );

        _titleLbl.frame = CGRectMake(, CGRectGetMaxY(_msgImgView.frame) + , SCREEN_WIDTH - , titleSize.height);

    }

    _contentLbl.frame = CGRectMake(, CGRectGetMaxY(_titleLbl.frame),  SCREEN_WIDTH - , contentSize.height + );

    if ([_model.jump isEqualToString:@""]) {

        _lineView.frame = CGRectZero;
        _lookLbl.frame = CGRectZero;

        _bgView.frame = CGRectMake(, CGRectGetMaxY(_msgDateLbl.frame), SCREEN_WIDTH - , CGRectGetMaxY(_contentLbl.frame));

    } else if ([_model.jump isEqualToString:@""]) {

        _lineView.frame = CGRectMake(, CGRectGetMaxY(_contentLbl.frame), SCREEN_WIDTH - , 0.5);
        _lookLbl.frame = CGRectMake(, CGRectGetMaxY(_lineView.frame), SCREEN_WIDTH - , );

        _bgView.frame = CGRectMake(, CGRectGetMaxY(_msgDateLbl.frame), SCREEN_WIDTH - , CGRectGetMaxY(_lookLbl.frame));

    }

}

3.在控制器中使用

.m

- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
    LBDNewMsgListModel *model = self.dataMutArr[indexPath.row];
    return model.cellHeight;
}