ios - viewWillAppear 未执行

Question

我有一个加载记录的表格 View ，请参阅下面的代码:

- (void)viewDidLoad
{
    self.navigationItem.title=@"Accounts";
//    NSString *accountFile = [[NSBundle mainBundle] pathForResource:@"Accounts2" ofType:@"plist"];
    NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
    NSString *documentPath = [paths objectAtIndex:0];
    NSString *plistPath = [documentPath stringByAppendingPathComponent:@"Accounts2.plist"];
    accounts = [[NSMutableDictionary alloc] initWithContentsOfFile:plistPath];
    NSLog(@"Accounts contains : %@", accounts);
    account = [accounts objectForKey:@"Account"];
    NSLog(@"account %@", account);
    number = [accounts objectForKey:@"Number"];
    dueDay = [accounts objectForKey:@"DayDue"];
    minAmount = [accounts objectForKey:@"MinAmount"];
    balance = [accounts objectForKey:@"Balance"];

    NSLog(@"data loaded"); 

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

- (void)insertNewObject:(id)sender
{
//    if (!_objects) {
//        _objects = [[NSMutableArray alloc] init];
 //   }
 //   [_objects insertObject:[NSDate date] atIndex:0];
 //   NSIndexPath *indexPath = [NSIndexPath indexPathForRow:0 inSection:0];
 //   [self.tableView insertRowsAtIndexPaths:@[indexPath] withRowAnimation:UITableViewRowAnimationAutomatic];
    if (!self.addView) {
        self.addView = [[AddView alloc] initWithNibName:@"AddView" bundle:nil];
    }
          [self.navigationController pushViewController:self.addView animated:YES];
    NSLog(@"I am done, now what");
}

#pragma mark - Table View

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

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
    NSLog(@"Number of records is %d", [account count]);
    return [account count];
}

// Customize the appearance of table view cells.
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    static NSString *CellIdentifier = @"Cell";

    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
    if (cell == nil) {
        cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:CellIdentifier];
        cell.accessoryType = UITableViewCellAccessoryDisclosureIndicator;
    }


     NSDate *object = _objects[indexPath.row];
     cell.textLabel.text = [object description];

    NSString *nameOfAccount = [account objectAtIndex:indexPath.row];
    cell.textLabel.text = nameOfAccount;
    NSString *accountNumber = [number objectAtIndex:indexPath.row];
    cell.detailTextLabel.text = accountNumber;
    NSLog(@"Index %d", indexPath.row);
    return cell;
}

我想向表中添加一条记录，所以我使用“InsertNewObject”方法...出现新屏幕，我可以将记录添加到我的 plist 中，然后在 DetailView 中执行以下行以返回:

[self.navigationController popToRootViewControllerAnimated:NO];

现在，我想用新记录重新加载 TableView:我想我只需要有以下 viewWillAppear 方法，如下所示:

- (void) viewWillAppear {
    NSLog(@"View will appear");
    [super viewWillAppear:YES];
    [self.tableView reloadData];

}

但是，我的 NSLog 从未执行过，因此我的程序永远不会到达这里...我是否做错了什么，谢谢您的回复

我添加了以下两个方法:

- (void) navigationController:(UINavigationController *) navigationController willShowViewController:(UIViewController *)viewController animated:(BOOL)animated{

    [self.tableView reloadData];

}

-(void) navigationController:(UINavigationController *) navigationController didShowViewController:(UIViewController *)viewController animated:(BOOL)animated{
    [self.tableView reloadData];
}

并更改了线路

[self.navigationController popToRootViewControllerAnimated:YES];

仍然无法工作，是不是还有问题。

Answer 1

您没有使用正确的方法。您省略了 animated 参数，请尝试使用 -(void)viewWillAppear:(BOOL)animated:

参见UIViewController -viewWillAppear:

- (void)viewWillAppear:(BOOL)animated {
    NSLog(@"View will appear");
    [self.tableView reloadData];
    [super viewWillAppear:animated];
}