Question

好的，所以我是iOS开发的新手。我刚刚创建了一个用于记笔记的主视图应用程序。除了一件事，在创建一个新单元格后，我停止应用程序并重新打开应用程序，新单元格不存在！

提前致谢！

Master View Controller.m

#import "MasterViewController.h"

#import "DetailViewController.h"

@interface MasterViewController () {
    NSMutableArray *_objects;
}
@end

@implementation MasterViewController
@synthesize myTableView, numbers;

- (void)awakeFromNib
{
    [super awakeFromNib];
}

- (void)viewDidLoad
{
    [super viewDidLoad];
    //NSMT arry
    numbers = [[NSMutableArray alloc]initWithObjects:@"One",@"Two",@"Three",@"Four", nil];
    // Do any additional setup after loading the view, typically from a nib.
    self.navigationItem.leftBarButtonItem = self.editButtonItem;

    UIBarButtonItem *addButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemAdd target:self action:@selector(insertNewObject:)];
    self.navigationItem.rightBarButtonItem = addButton;

}
- (void)viewWillAppear:(BOOL)animated {

}
-(void)viewWillDisappear:(BOOL)animated{

}


- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

- (void)insertNewObject:(id)sender
{
    UIAlertView * alert = [[UIAlertView alloc] initWithTitle:@"Enter" message:@"" delegate:self cancelButtonTitle:@"Cancel" otherButtonTitles:@"Ok", nil];

    alert.alertViewStyle = UIAlertViewStylePlainTextInput;
    [alert show];

    /*
     if (!numbers) {
     numbers = [[NSMutableArray alloc] init];
     }
     [numbers insertObject:[NSDate date] atIndex:0];
     NSIndexPath *indexPath = [NSIndexPath indexPathForRow:0 inSection:0];
     [self.tableView insertRowsAtIndexPaths:@[indexPath] withRowAnimation:UITableViewRowAnimationAutomatic];
     */
}
-(void)setEditing:(BOOL)editing animated:(BOOL)animated
{
    [super setEditing:editing animated:animated];
    [myTableView setEditing:editing animated:animated];
}
#pragma mark - Table View

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
    return 1;
}

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
    return numbers.count;
}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:@"Cell" forIndexPath:indexPath];

    cell.textLabel.text = [numbers objectAtIndex:indexPath.row];
    return cell;
}

- (BOOL)tableView:(UITableView *)tableView canEditRowAtIndexPath:(NSIndexPath *)indexPath
{
    // Return NO if you do not want the specified item to be editable.
    return YES;
}

- (void)tableView:(UITableView *)tableView commitEditingStyle:(UITableViewCellEditingStyle)editingStyle forRowAtIndexPath:(NSIndexPath *)indexPath
{
    if (editingStyle == UITableViewCellEditingStyleDelete) {
        [numbers removeObjectAtIndex:indexPath.row];
        [tableView deleteRowsAtIndexPaths:@[indexPath] withRowAnimation:UITableViewRowAnimationFade];
    } else if (editingStyle == UITableViewCellEditingStyleInsert) {
        // Create a new instance of the appropriate class, insert it into the array, and add a new row to the table view.
    }
}
- (void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex
{
    //if user hits OK
    if (buttonIndex == 1) {
        NSString * tempTextField = [alertView textFieldAtIndex:0].text;
        if (!numbers) {
            numbers = [[NSMutableArray alloc] init];
        }
        [numbers insertObject:tempTextField atIndex:0];

        NSIndexPath *indexPath = [NSIndexPath indexPathForRow:0 inSection:0];
        [self.myTableView insertRowsAtIndexPaths:@[indexPath] withRowAnimation:UITableViewRowAnimationAutomatic];
    }

}
/*
 // Override to support rearranging the table view.
 - (void)tableView:(UITableView *)tableView moveRowAtIndexPath:(NSIndexPath *)fromIndexPath toIndexPath:(NSIndexPath *)toIndexPath
 {
 }
 */

/*
 // Override to support conditional rearranging of the table view.
 - (BOOL)tableView:(UITableView *)tableView canMoveRowAtIndexPath:(NSIndexPath *)indexPath
 {
 // Return NO if you do not want the item to be re-orderable.
 return YES;
 }
 */

- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
    if ([[segue identifier] isEqualToString:@"showDetail"]) {
        NSIndexPath *indexPath = [self.tableView indexPathForSelectedRow];
        NSDate *object = _objects[indexPath.row];
        [[segue destinationViewController] setDetailItem:object];
    }
}

@end

MasterViewController.h

#import <UIKit/UIKit.h>

@interface MasterViewController : UITableViewController
<UITableViewDataSource, UITableViewDelegate, UIAlertViewDelegate>

@property (strong, nonatomic) IBOutlet UITableView *myTableView;
@property (strong, nonatomic) NSMutableArray * numbers;


@end

Answer 1

或许告诉我们您如何存储用于填充tableview的数据。因为这是你需要保存的。

您可以使用CoreData保存它或只使用NSUserDefaults，有很多选项可供您使用。但是，如果不知道您当前的数据结构，很难给出一个具体的例子。

显示一些代码，你会得到更好的答案。

添加新单元格后，如何让UITableViewController保存新条目，所以当应用程序关闭并重新打开时，新单元格就在那里

1 个答案: