IOS 滚动列表的分组功能

1.惯例 效果图奉上：

1. 滚动列表的Section与Row分析（UICollectionView UITableView）

一个section 里面可以有多个row ,正是这个特性才能够达到分组效果

3.1 组头视图 对应的接口为：

    - (UIView *)tableView:(UITableView *)tableView viewForHeaderInSection:(NSInteger)section

4 组的展开与收缩：

• 使用一个列表来记录当前组头的点击状态，点击的时候取反即可

//
//  ViewController.m
//  GroupTabView
//
//  Created by 刘小兵 on 2018/6/8.
//  Copyright © 2018 刘小兵. All rights reserved.
//

#import "ViewController.h"
#define kCell_Height 44

@interface ViewController (){


    UITableView         *expandTable;
    NSMutableArray      *dataSource;
    NSMutableArray      *sectionArray;
    NSMutableArray      *stateArray;

}

@end

@implementation ViewController

- (void)initDataSource
{
    sectionArray  = [NSMutableArray arrayWithObjects:@"东南大学",
                     @"南京大学",
                     @"上第交通大学",
                     @"武汉大学",nil];

    NSArray *one = @[@"计算机",@"美术",@"音乐",@"经济管理"];
    NSArray *two = @[@"物理",@"理论数学",@"金融",@"天体"];
    NSArray *three = @[@"临床医学",@"计算机"];
    NSArray *four = @[@"中文",@"计算机",@"汉语言文学",@"美术"];

    dataSource = [NSMutableArray arrayWithObjects:one,two,three,four, nil];
    stateArray = [NSMutableArray array];

    for (int i = 0; i < dataSource.count; i++)
    {
        //所有的分区都是闭合
        [stateArray addObject:@"0"];
    }
}
- (void)viewDidLoad {
    self.title = @"折叠的tableView";
    [super viewDidLoad];
    self.view.backgroundColor = [UIColor whiteColor];
    [self initDataSource];
    [self initTable];
}
-(void)initTable{
    expandTable = [[UITableView alloc]initWithFrame:CGRectMake(0, 0, self.view.frame.size.width, self.view.frame.size.height) style:UITableViewStylePlain];
    expandTable.dataSource = self;
    expandTable.delegate =  self;
    expandTable.tableFooterView = [UIView new];

    //[expandTable registerClass:[ExpandCell class] forCellReuseIdentifier:@"cell"];

    [self.view addSubview:expandTable];
}
#pragma mark -
#pragma mark - UITableViewDataSource UITableViewDelegate
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
    return dataSource.count;
}

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
    if ([stateArray[section] isEqualToString:@"1"]){
        NSArray *array = [dataSource objectAtIndex:section];
        return array.count;
    }else{
        return 0;
    }
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{

    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:@"cell"];
    if (cell == nil) {
        cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:@"cell"];
    }
    cell.textLabel.text= [NSString stringWithFormat:@"第%ld组的第%ld个cell",(long)indexPath.section,(long)indexPath.row];
    //cell.clipsToBounds = YES;
    return cell;
}

- (NSString *)tableView:(UITableView *)tableView titleForHeaderInSection:(NSInteger)section
{
    return sectionArray[section];
}


- (UIView *)tableView:(UITableView *)tableView viewForHeaderInSection:(NSInteger)section
{
    UIButton *button = [UIButton buttonWithType:UIButtonTypeCustom];
    [button setFrame:CGRectMake(0, 0, self.view.frame.size.width, 44)];
    [button setTag:section+1];
    button.backgroundColor = [UIColor whiteColor];
    [button setTitleColor:[UIColor grayColor] forState:UIControlStateNormal];
    [button setTitleEdgeInsets:UIEdgeInsetsMake(0, 0, 0, 60)];
    [button addTarget:self action:@selector(buttonPress:) forControlEvents:UIControlEventTouchUpInside];
    UIImageView *line = [[UIImageView alloc]initWithFrame:CGRectMake(0, button.frame.size.height-1, button.frame.size.width, 1)];
    [line setImage:[UIImage imageNamed:@"line_real"]];
    [button addSubview:line];

    UIImageView *imgView = [[UIImageView alloc]initWithFrame:CGRectMake(10, (kCell_Height-22)/2, 22, 22)];
    [imgView setImage:[UIImage imageNamed:@"ico_faq_d"]];
    [button addSubview:imgView];

    UIImageView *_imgView = [[UIImageView alloc]initWithFrame:CGRectMake(self.view.frame.size.width-30, (kCell_Height-6)/2, 10, 6)];

    if ([stateArray[section] isEqualToString:@"0"]) {
        _imgView.image = [UIImage imageNamed:@"ico_listdown"];
    }else if ([stateArray[section] isEqualToString:@"1"]) {
        _imgView.image = [UIImage imageNamed:@"ico_listup"];
    }
    [button addSubview:_imgView];

    UILabel *tlabel = [[UILabel alloc]initWithFrame:CGRectMake(45, (kCell_Height-20)/2, 200, 20)];
    [tlabel setBackgroundColor:[UIColor clearColor]];
    [tlabel setFont:[UIFont systemFontOfSize:14]];
    [tlabel setText:sectionArray[section]];
    [button addSubview:tlabel];
    return button;
}
#pragma mark
#pragma mark  -select cell
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{

}

- (void)buttonPress:(UIButton *)sender//headButton点击
{
    //判断状态值
    if ([stateArray[sender.tag - 1] isEqualToString:@"1"]){
        //修改
        [stateArray replaceObjectAtIndex:sender.tag - 1 withObject:@"0"];
    }else{
        [stateArray replaceObjectAtIndex:sender.tag - 1 withObject:@"1"];
    }
    [expandTable reloadSections:[NSIndexSet indexSetWithIndex:sender.tag-1] withRowAnimation:UITableViewRowAnimationAutomatic];

}

- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
    return kCell_Height;
}
- (CGFloat)tableView:(UITableView *)tableView heightForFooterInSection:(NSInteger)section
{
    return 0.00001;
}
- (CGFloat)tableView:(UITableView *)tableView heightForHeaderInSection:(NSInteger)section
{
    return kCell_Height;
}


@end