ios - 将数据解析回 View Controller

Question

我是 ios 编程新手；我编写了一个应用程序以在 UITableView 中显示食谱列表，并在选择一行后，在详细 View 中将行标题解析为 UITextField。

问题:我该怎么做才能将详细 View 中的标题更改保存到表格 View (我使用 Storyboard)？

这是我的代码:

NViewController.m:

- (void)viewDidLoad
{
    [super viewDidLoad];

    recipes = [NSArray arrayWithObjects:@"Egg Benedict", @"Mushroom Risotto", @"Full Breakfast", nil];
}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    static NSString *simpleTableIdentifier = @"RecipeCell";
    MyTableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:simpleTableIdentifier];
    if (cell == nil) {
        cell = [[MyTableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:simpleTableIdentifier];
    }
    cell.lblName.text = [recipes objectAtIndex:indexPath.row];
    return cell;
}

- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {
    if ([segue.identifier isEqualToString:@"showRecipeDetail"]) {
        NSIndexPath *indexPath = [self._tableView indexPathForSelectedRow];
        NDetailViewController *destViewController = segue.destinationViewController;
        destViewController.selectedRowTitle = [recipes objectAtIndex:indexPath.row];
    }
}

NDetailViewController.m:

@interface NDetailViewController ()
@property (weak, nonatomic) IBOutlet UITextField *txtDetailText;

@end

@implementation NDetailViewController

@synthesize selectedRowTitle;

- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
    self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
    if (self) {
        // Custom initialization

    }
    return self;
}

- (void)viewDidLoad
{
    [super viewDidLoad];

    self.txtDetailText.text = selectedRowTitle;
}

Answer 1

在NViewController中，添加NSIndexPath来保存:

- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {
if ([segue.identifier isEqualToString:@"showRecipeDetail"]) {
    NSIndexPath *indexPath = [self._tableView indexPathForSelectedRow];
    NDetailViewController *destViewController = segue.destinationViewController;
    destViewController.selectedRowTitle = [recipes objectAtIndex:indexPath.row];

    // need to save this indexPath to update when textfield is changed. Because indexPath maybe change if data changes, I think you should choose another field (like KEY, distingue objects)
    destViewController.indexPath = indexPath;
    destViewController.delegate = self;
}
}

-(void)changeTextFieldWithIndexPath : (NSIndexPath*)indexPath content:(NSString*)content;
{
 // you update indexPath to row, and reloadTable
}

NDetailViewController.h:

@protocol NDetailViewControllerDelegate <NSObject>
-(void)changeTextFieldWithIndexPath : (NSIndexPath*)indexPath content:(NSString*)content;
@end

@interface NDetailViewController : ViewController
@property (nonatomic, weak) id<NDetailViewControllerDelegate> delegate;
@end

NDetailViewController.m:当textfiled改变值时，我的方法只是一个例子:

- (void) whenContentOfTextFieldChanged
{
[self.delegate changeTextFieldWithIndexPath:indexPath content:@"content which textfield is changed"];
}