下面我们通过实例代码来一步步看怎么实现, 首先建立了两个模型类, 一个Friend, 一个FriendGroup类. 数据源用的本地的一个plist文件. plist文件中包含了FriendGroup的name,friends数组等属性.
Friend.h 示例代码
#import <Foundation/Foundation.h>
@interface Friend : NSObject
@property (nonatomic, copy) NSString *name;
@end
FriendGroup.h 示例代码
#import <Foundation/Foundation.h>
@interface FriendGroup : NSObject
@property (nonatomic, copy) NSString *name;
// 数组中存放的为Friend类的实例对象
@property (nonatomic, copy) NSMutableArray *friends;
// 用来判断分组是否打开(opened属性正是实现下拉列表的关键)
@property (nonatomic, assign, getter = isOpened) BOOL opened;
// 自定义方法用来赋值
-(void)setFriendGroupDic:(NSMutableDictionary *)dic;
@end
FriendGroup.m 示例代码
#import "FriendGroup.h"
#import "Friend.h"
@implementation FriendGroup
-(void)setFriendGroupDic:(NSMutableDictionary *)dic
{
// 通过字典给FriendGroup的属性赋值
[self setValuesForKeysWithDictionary:dic];
NSMutableArray *tempArray = [NSMutableArray array];
// 遍历friends属性数组
for (NSMutableDictionary *dic in self.friends) {
Friend *friend = [[Friend alloc] init];
[friend setValuesForKeysWithDictionary:dic];
[tempArray addObject:friend];
}
//重新对friends属性数组赋值,此时存的都是Friend对象
self.friends = [NSMutableArray arrayWithArray:tempArray];
}
@end
在ViewController中创建一个tableView
#import "ViewController.h"
#import "SectionView.h"
#import "FriendGroup.h"
#import "Friend.h"
#define kTableViewReuse @"reuse"
@interface ViewController ()<UITableViewDelegate, UITableViewDataSource, SectionViewDelegate>
@property (nonatomic, strong) UITableView *tableView;
// 数组中存放FriendGroup的实例对象
@property (nonatomic, strong) NSMutableArray *allArray;
@end
@implementation ViewController
- (void)viewDidLoad {
[super viewDidLoad];
self.allArray =[NSMutableArray array];
[self creatTableView];
[self getData];
}
- (void)creatTableView {
self.tableView = [[UITableView alloc] initWithFrame:self.view.bounds style:UITableViewStylePlain];
_tableView.delegate = self;
_tableView.dataSource = self;
[_tableView registerClass:[UITableViewCell class] forCellReuseIdentifier:kTableViewReuse];
[self.view addSubview:_tableView];
}
// 获取数据
- (void)getData {
NSString *filePath = [[NSBundle mainBundle] pathForResource:@"friends.plist" ofType:nil];
NSArray *tempArray = [NSArray arrayWithContentsOfFile:filePath];
for (NSMutableDictionary *dic in tempArray) {
FriendGroup *friendGroup = [[FriendGroup alloc] init];
[friendGroup setFriendGroupDic:dic];
[self.allArray addObject:friendGroup];
}
[self.tableView reloadData];
}
- (CGFloat)tableView:(UITableView *)tableView heightForHeaderInSection:(NSInteger)section {
return 50;
}
// SectionView必须实现的协议方法
- (void)touchAction:(SectionView *)sectionView {
}
#pragma mark - TableView Delegate
-(UIView *)tableView:(UITableView *)tableView viewForHeaderInSection:(NSInteger)section
{
FriendGroup *friendGroup = [self.allArray objectAtIndex:section];
//放一个封装的view,view上有一个label和imageVIew,自带touch事件,点击触发协议方法
SectionView *sectionView = [[SectionView alloc] initWithFrame:CGRectMake(0, 0, 375, 50)];
sectionView.delegate = self;
sectionView.tag = section + 1000;
sectionView.textLabel.text = friendGroup.name;
sectionView.group = friendGroup;
return sectionView;
}
#pragma mark - TableView DataSource
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView {
return _allArray.count;
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
return [_allArray[section] friends].count;
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:kTableViewReuse];
FriendGroup *friendGroup = _allArray[indexPath.section];
Friend *friend = friendGroup.friends[indexPath.row];
cell.textLabel.text = friend.name;
return cell;
}
#pragma mark - Memory Waring
- (void)didReceiveMemoryWarning {
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
@end
