展开和折叠所有表格视图单元格

debugcn 发表于 Dev

巴金斯先生

我需要一些UI建议。

我有一个视图，需要加载这样的格式的数据：

    {
      "heading": "This is a header",
      "content": "This is some detailed content about the header"
    },
    {
      "heading": "This is another headline.",
      "content": " These are more details about the headline. "
    }

这里是参数：加载时，它应该仅在表格视图中显示标题。点击标题将扩展该单元格并加载其内容或详细信息。这是一个粗略的草图：

负载：

标题1
标题2
标题3
标题4

在标题2上：

标题1
标题2
- 标题2的内容在此处显示
标题3
标题4

还需要有一个将扩展或折叠所有单元格的条形按钮项。哪个会这样：

全部收缩：

标题1
标题2
标题3
标题4

展开全部：

标题1
- 标题1的内容在此处显示
标题2
- 标题2的内容在此处显示
标题3
- 标题3的内容在此处显示
标题4
- 标题4的内容在此处显示

我使用了一些怪异的父/子逻辑来扩展单个单元格，但是我想我走了一条黑暗的路，因为现在我试图实现全部扩展/折叠，而我被困住了。

有谁知道做这种手风琴表格视图的任何开源代码和/或关于如何设置视图控制器来做到这一点的任何建议？我已经看到一些库可以扩展和折叠单个单元格，但是能够完成所有这些单元变得很棘手。

杰夫

这就是我的方法，也许稍微简单一些，尽管绝对是相似的方法:)

#import "ViewController.h"

//dont worry, the header is empty except for import <UIKit/UIKit.h>, this is a subclass on UIViewController

@interface ViewController ()<UITableViewDataSource, UITableViewDelegate>

@property (weak, nonatomic) UITableView *tableView;


@end

@implementation ViewController
{
//ivars
  BOOL sectionIsOpen[4]; //we will use this BOOL array to keep track of the open/closed state for each section.  Obviously I have the number of sections fixed at 4 here, but you could make a more dynamic array with malloc() if neccesary..
}



- (void)viewDidLoad {
  [super viewDidLoad];

  UITableView *tv = [[UITableView alloc]initWithFrame:self.view.bounds style:UITableViewStyleGrouped];
  tv.autoresizingMask = UIViewAutoresizingFlexibleHeight | UIViewAutoresizingFlexibleWidth;
  tv.dataSource = self;
  tv.delegate = self;

  [self.view addSubview:tv];
  self.tableView = tv;

  // Do any additional setup after loading the view, typically from a nib.
}

#pragma mark - UITableViewDataSource
-(NSInteger )numberOfSectionsInTableView:(UITableView *)tableView{
  return 4;
}

-(NSInteger )tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section{
  return ((sectionIsOpen[section]) ? [self numberOfRowsInSection:section] : 0);
}
-(NSString *)tableView:(UITableView *)tableView titleForHeaderInSection:(NSInteger)section{

  //put your switch() here...

  return [NSString stringWithFormat:@"I am section %i", (int)section ];
}
-(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath{

  static NSString *cellId = @"cellID";

  UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:cellId];

  if (!cell) {
    cell = [[UITableViewCell alloc]initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:cellId];
  }


 //etc etc decorate your cell...
  cell.textLabel.text = [NSString stringWithFormat:@"cell %i / %i", (int)indexPath.section, (int)indexPath.row ];


  return cell;
}
#pragma mark - UITableViewDelegate
-(UIView *)tableView:(UITableView *)tableView viewForHeaderInSection:(NSInteger)section{

  const CGRect fr = CGRectMake(0, 0, 320.0, 40.0 );

  UIButton *btn = [[UIButton alloc]initWithFrame:fr];
  [btn setTitle:[self tableView:tableView titleForHeaderInSection:section] forState:UIControlStateNormal ];
  [btn setTag:section];
  [btn addTarget:self action:@selector(sectionOpenToggle:) forControlEvents:UIControlEventTouchUpInside];


  // add an image, colour etc if you like

  return btn;
}



#pragma mark - tableViewHelpers

//the number of rows in sectionX when it is open...
-(NSInteger )numberOfRowsInSection:(NSInteger )section{

  return section + 1;
}

//opening/closing a section
-(void )setSection:(NSInteger )section toOpen:(BOOL )open{

  if (open != sectionIsOpen[section]) {

//build an array of indexPath objects
    NSMutableArray *indxPths = [NSMutableArray array];
    for (NSInteger i = 0; i < [self numberOfRowsInSection:section]; i ++) {

      [indxPths addObject: [NSIndexPath indexPathForRow:i inSection:section ]
       ];

    }


    [self.tableView beginUpdates];

    if (open) {
      [self.tableView insertRowsAtIndexPaths:indxPths withRowAnimation:UITableViewRowAnimationFade];
      //nb there is a large ENUM of tableViewRowAnimation types to experiment with..

    }else{
      [self.tableView deleteRowsAtIndexPaths:indxPths withRowAnimation:UITableViewRowAnimationFade];

    }
    sectionIsOpen[section] = open;
    [self.tableView endUpdates];

  }
}

-(void )sectionOpenToggle:(id )sender{
  [self setSection:[sender tag] toOpen: !sectionIsOpen[[sender tag]] ];
}

// open/close all sections.
-(void )setAllSectionsOpen:(BOOL )open{

  for (NSInteger i = 0; i < [self numberOfSectionsInTableView:self.tableView]; i ++) {
    [self setSection:i toOpen:open];
  }
}


//these two for your convenience, hook up to navbar items etc..
-(IBAction)openAllSections:(id)sender{
  [self setAllSectionsOpen:YES];
}
-(IBAction)closeAllSections:(id)sender{
  [self setAllSectionsOpen:NO];
}
@end