iOS tableviewcell里点击文字展开与收起功能

妖狐艹你老母 2022-12-13 12:48 804阅读 0赞

做项目遇到动态列表中需要做文字展开与收起功能，有空单独抽出一个demo给大家参考。  
1、效果图如下：  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3NtaWxlS0g_size_16_color_FFFFFF_t_70_pic_center]  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3NtaWxlS0g_size_16_color_FFFFFF_t_70_pic_center 1]

2、创建tableview与添加数据

- (void)viewDidLoad {
        [super viewDidLoad];
        self.view.backgroundColor = [UIColor whiteColor];
        self.title = @"在tablecell中文本的展开与收起";
        self.allData = [NSMutableArray array];
        //添加子视图
        [self addSubViewUI];
        //请求数据
        [self requestMessageListData];
        //增加刷新
        [self addRefresh];
    }

模拟请求数据

#pragma mark ==========请求数据==========
    -(void)requestMessageListData{
        NSArray *arr = @[ ];
        for (int i = 0; i<10; i++) {
            HBTextChangeModel *model = [HBTextChangeModel new];
            model.content = arr[arc4random_uniform(10)];
            [self.allData addObject:model];
        }
        [self endRefresh];
        [self.tableView reloadData];
    }

设置上拉加载，下拉刷新

- (void)endRefresh{
        if (self.tableView.mj_header.refreshing) {
            [self.tableView.mj_header endRefreshing];
        }
        if (self.tableView.mj_footer.refreshing) {
            [self.tableView.mj_footer endRefreshing];
        }
    }
    - (void)addRefresh{
        WEAKSELF;
        self.tableView.mj_header = [MJRefreshNormalHeader headerWithRefreshingBlock:^{
            //请求数据
           // weakSelf.pageNo = 1;
            [weakSelf.allData removeAllObjects];
            [weakSelf requestMessageListData];
        }];
        self.tableView.mj_footer = [MJRefreshBackNormalFooter footerWithRefreshingBlock:^{
            //请求数据
            //weakSelf.pageNo++;
            [weakSelf requestMessageListData];
        }];
    }

添加子视图

#pragma mark ==========添加子视图==========
    -(void)addSubViewUI{
        [self.view addSubview:self.backBtn];
        [self.backBtn mas_makeConstraints:^(MASConstraintMaker *make) {
            make.top.equalTo(self.view).offset(20);
            make.left.equalTo(self.view).offset(15);
            make.size.mas_equalTo(CGSizeMake(100, 25));
        }];
        
        [self.view addSubview:self.tableView];
        [self.tableView mas_makeConstraints:^(MASConstraintMaker *make) {
            make.top.equalTo(self.backBtn.mas_bottom);
            make.bottom.equalTo(self.view);
            make.left.right.equalTo(self.view);
        }];
    }
    #pragma mark ==========tableViewDelegate==========
    - (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView{
        return self.allData.count;
    }
    
    - (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section{
        return 1;
    }
    
    #pragma mark ==========tableview代理方法==========
    - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath{
        HBTextChangeTabCell *cell = [tableView dequeueReusableCellWithIdentifier:@"HBTextChangeTabCell"];
        if (cell == nil) {
            cell = [[HBTextChangeTabCell alloc]initWithStyle:UITableViewCellStyleDefault reuseIdentifier:@"HBTextChangeTabCell"];
        }
        cell.selectionStyle = UITableViewCellSelectionStyleNone;
        cell.backgroundColor = [UIColor clearColor];
        HBTextChangeModel *model = self.allData[indexPath.section];
        cell.model = model;
        WEAKSELF;
        cell.updateMessageCellBlock = ^(NSString * _Nonnull str) {
            [weakSelf.tableView reloadRowsAtIndexPaths:@[indexPath] withRowAnimation:UITableViewRowAnimationAutomatic];
        };
        [cell layoutIfNeeded];
        return cell;
    }
    - (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath{
        return UITableViewAutomaticDimension;
    }
    
    - (CGFloat)tableView:(UITableView *)tableView heightForHeaderInSection:(NSInteger)section {
        return 15;
    }
    -(UIView *)tableView:(UITableView *)tableView viewForHeaderInSection:(NSInteger)section{
        //全部商品
        UIView *headerView = [[UIView alloc]initWithFrame:CGRectMake(0, 0, SCREEN_WIDTH, 15)];
        headerView.backgroundColor = [UIColor grayColor];
        return headerView;
    }
    - (CGFloat)tableView:(UITableView *)tableView heightForFooterInSection:(NSInteger)section {
        return 0.01;
    }
    -(UIView *)tableView:(UITableView *)tableView viewForFooterInSection:(NSInteger)section{
        //全部商品
        UIView *footerView = [[UIView alloc]initWithFrame:CGRectMake(0, 0, SCREEN_WIDTH, 0.01)];
        footerView.backgroundColor = [UIColor clearColor];
        return footerView;
    }
    
    
    -(void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath{
     
    }
    
    #pragma mark ==========tableViewGetter==========
    -(UITableView *)tableView{
        if (!_tableView) {
            _tableView = ({
                UITableView *tableView = [[UITableView alloc]initWithFrame:CGRectZero style:UITableViewStylePlain];
                tableView.dataSource = self;
                tableView.delegate = self;
                tableView.backgroundColor = [UIColor clearColor];
                //设置分割线样式
                tableView.separatorStyle = UITableViewCellSeparatorStyleSingleLine;
                //cell的分割线距视图距离
                tableView.separatorInset=UIEdgeInsetsMake(0, 0, 0, 0);
                //隐藏底部多余分割线
                tableView.tableFooterView = [[UIView alloc] initWithFrame:CGRectZero];
                //iOS11默认开启Self-Sizing，需关闭才能设置Header,Footer高度
                tableView.estimatedRowHeight = 66;
                tableView.estimatedSectionHeaderHeight = 0;
                tableView.estimatedSectionFooterHeight = 0;
                tableView.rowHeight = 50 ;
                tableView.tableHeaderView = [[UIView alloc] initWithFrame:CGRectZero];;
                tableView ;
            }) ;
        }
        return _tableView;
    }
    -(UIButton *)backBtn{
        if (!_backBtn) {
            _backBtn = ({
                //创建按钮
                UIButton * button = [UIButton buttonWithType:UIButtonTypeCustom];
                //设置标题
                [button setTitle:@"返回" forState:UIControlStateNormal];
                //设置字体大小
                button.titleLabel.font = [UIFont systemFontOfSize:14];
                //设置title颜色
                [button setTitleColor:[UIColor blackColor] forState:UIControlStateNormal];
                //添加点击事件
                [button addTarget:self action:@selector(clickBackButton:) forControlEvents:UIControlEventTouchUpInside];
                
                button;
            });
        }
        return _backBtn;
    }
    #pragma mark ==========点击返回==========
    -(void)clickBackButton:(UIButton *)button{
        [self dismissViewControllerAnimated:YES completion:nil];
    }

3、cell中的核心代码:

-(void)setModel:(HBTextChangeModel *)model{
        _model = model;
        NSString *desc = model.content;
        if (desc) {
            //计算文本高度
            CGFloat height = [desc heightWithStrAttri:@{NSFontAttributeName:FONT(15), NSForegroundColorAttributeName: Color_label_DataTitle,NSParagraphStyleAttributeName:[self paragraphStyle]} withLabelWidth:SCREEN_WIDTH];
            if (height > 67) { //超过3行
                if (model.showAll) {
                    //拼接再算高度
                    height = [[NSString stringWithFormat:@"%@...收起",desc] heightWithStrAttri:@{NSFontAttributeName:FONT(15), NSForegroundColorAttributeName: Color_label_DataTitle,NSParagraphStyleAttributeName:[self paragraphStyle]} withLabelWidth:SCREEN_WIDTH];
                    
                    [self.contentBaseView mas_updateConstraints:^(MASConstraintMaker *make) {
                        make.height.mas_equalTo(height+5);
                    }];
                    self.contentLabel.truncationToken = nil;
                    [self setShowTextWithDesc:desc];
                } else {
                    
                    [self.contentBaseView mas_updateConstraints:^(MASConstraintMaker *make) {
                        make.height.mas_equalTo(67);
                    }];
                    [self setAdjustableTextWithDesc:desc];
                }
            } else {
                [self.contentBaseView mas_updateConstraints:^(MASConstraintMaker *make) {
                    make.height.mas_equalTo(height+10);
                }];
                NSMutableAttributedString *text = [[NSMutableAttributedString alloc] initWithString:desc attributes:@{ NSFontAttributeName:FONT(15), NSParagraphStyleAttributeName : [self paragraphStyle]}];
                self.contentLabel.attributedText = text;
            }
        }
    }
    - (void)setShowTextWithDesc:(NSString *)desc
    {
        NSMutableAttributedString *text = [[NSMutableAttributedString alloc] initWithString:[NSString stringWithFormat:@"%@...收起",desc] attributes:@{ NSFontAttributeName:FONT(15), NSParagraphStyleAttributeName : [self paragraphStyle]}];
        
        WEAKSELF;
        //设置高亮色和点击事件
        [text setTextHighlightRange:[[text string] rangeOfString:@"收起"] color:[UIColor colorWithHexString:@"#0099FF"] backgroundColor:[UIColor clearColor] tapAction:^(UIView * _Nonnull containerView, NSAttributedString * _Nonnull text, NSRange range, CGRect rect) {
            weakSelf.model.showAll = NO;
            if (self.updateMessageCellBlock) {
                self.updateMessageCellBlock(@"");
            }
    
        }];
        self.contentLabel.attributedText = text;
    }
    
    - (NSMutableParagraphStyle *)paragraphStyle {
        NSMutableParagraphStyle *para = [NSMutableParagraphStyle new];
        para.lineSpacing = 5.f;
        return para;
    }
    
    - (void)setAdjustableTextWithDesc:(NSString *)desc
    {
        NSMutableAttributedString *text = [[NSMutableAttributedString alloc] initWithString:desc attributes:@{ NSFontAttributeName:FONT(15), NSParagraphStyleAttributeName : [self paragraphStyle]}];
        self.contentLabel.attributedText = text;
        
        WEAKSELF;
        NSMutableAttributedString *showAll = [[NSMutableAttributedString alloc] initWithString:@"...展开" attributes:nil];
        YYTextHighlight *hi = [YYTextHighlight new];
        [hi setColor:[UIColor colorWithHexString:@"#009900"]];
        hi.tapAction = ^(UIView *containerView,NSAttributedString *text,NSRange range, CGRect rect) {
            weakSelf.model.showAll = YES;
            if (self.updateMessageCellBlock) {
                self.updateMessageCellBlock(@"");
            }
        };
        
        NSRange range = [showAll.string rangeOfString:@"展开"];
        [showAll setColor:[UIColor colorWithHexString:@"#0099FF"] range:range];
        [showAll setTextHighlight:hi range:range];
        showAll.font = FONT(15);
        YYLabel *seeMore = [YYLabel new];
        seeMore.attributedText = showAll;
        [seeMore sizeToFit];
        seeMore.height += 2.f;
        NSAttributedString *truncationToken = [NSAttributedString attachmentStringWithContent:seeMore contentMode:UIViewContentModeCenter attachmentSize:seeMore.frame.size alignToFont:FONT(15) alignment:YYTextVerticalAlignmentTop];
        self.contentLabel.truncationToken = truncationToken;
    }

最后附上[demo连接][demo]

END.

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3NtaWxlS0g_size_16_color_FFFFFF_t_70_pic_center]: /images/20221123/ecf4dedec4cd4d4993a5e52ac8be8254.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3NtaWxlS0g_size_16_color_FFFFFF_t_70_pic_center 1]: /images/20221123/aeb83a1b8267409fb360f553edc6156c.png
[demo]: https://github.com/smileKH/HBTextShowAndPackUp.git