原理很简单，一级菜单放在viewForHeaderInSection里面，加一个点击事件，然后判断它的二级菜单（cell）显不显示。
直接上代码吧！
//
// HeheTableViewController.m
// Demo-tableView
//
// Created by yyt on 16/5/13.
// Copyright © 2016年 yyt. All rights reserved.
//
#import "HeheTableViewController.h"
#define klScreenWidth self.view.bounds.size.width
@interface HeheTableViewController ()
@property(nonatomic,strong) NSArray *dataArr;
@property(nonatomic,strong) NSMutableArray *tapButtons;
@property(nonatomic,strong) NSMutableArray *openedIndexArr;
@end
@implementation HeheTableViewController
- (void)viewDidLoad {
[super viewDidLoad];
_dataArr = @[@{@"name":@"A区",
@"arr":@[@"A1",@"A2",@"A3",@"A4"]
},
@{@"name":@"B区",
@"arr":@[@"B1",@"B2",@"B3"]
},
@{@"name":@"C区",
@"arr":@[@"C1",@"C2",@"C3",@"C4",@"C5",@"C6"]
},
@{@"name":@"D区",
@"arr":@[@"D1",@"D2",@"D3",@"D4",@"D5"]
}
];
_tapButtons = [NSMutableArray array];
_openedIndexArr = [NSMutableArray array];
}
#pragma mark - TableViewDataSource
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView {
return _dataArr.count;
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
NSString *str = [NSString stringWithFormat:@"%ld",section];
if ([_openedIndexArr containsObject:str]) {
NSDictionary *dict = _dataArr[section];
NSArray *arr = dict[@"arr"];
return arr.count;
}
return 0;
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
UITableViewCell *cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleValue1 reuseIdentifier:@"cell"];
NSString *str = [NSString stringWithFormat:@"%ld",indexPath.section];
if ([_openedIndexArr containsObject:str]) {
NSDictionary *dict = _dataArr[indexPath.section];
NSArray *arr = dict[@"arr"];
cell.textLabel.text = arr[indexPath.row];
}
cell.selectionStyle = UITableViewCellSelectionStyleNone;
return cell;
}
#pragma mark - TableViewDelegate
- (CGFloat)tableView:(UITableView *)tableView heightForHeaderInSection:(NSInteger)section {
return 50;
}
- (UIView*)tableView:(UITableView *)tableView viewForHeaderInSection:(NSInteger)section {
UIView *bgView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, klScreenWidth, 50)];
bgView.backgroundColor = [UIColor greenColor];
NSDictionary *dict = _dataArr[section];
NSString *title = dict[@"name"];
UILabel *titleLabel = [[UILabel alloc] initWithFrame:CGRectMake(20, 10, klScreenWidth-40, 30)];
titleLabel.text = title;
titleLabel.textColor = [UIColor whiteColor];
titleLabel.font = [UIFont systemFontOfSize:22];
[bgView addSubview:titleLabel];
UIButton *tapButton = [UIButton buttonWithType:UIButtonTypeCustom];
tapButton.frame = bgView.frame;
[tapButton addTarget:self action:@selector(openOrCloseSectionView:) forControlEvents:UIControlEventTouchUpInside];
[_tapButtons addObject:tapButton];
[bgView addSubview:tapButton];
return bgView;
}
- (void)openOrCloseSectionView:(UIButton*)sender {
NSInteger index = [_tapButtons indexOfObject:sender];
NSString *str = [NSString stringWithFormat:@"%ld",index];
if ([_openedIndexArr containsObject:str]) {
[_openedIndexArr removeObject:str];
} else {
[_openedIndexArr addObject:str];
}
[_tapButtons removeAllObjects];
[self.tableView reloadData];
}
@end