iphone - 如何以编程方式取消 segue 并保持在同一 View 中

Question

我想知道当某些条件为 false 时我们如何取消程序中的 segue？

下面是我的代码片段:

if ([segue.identifier isEqualToString:@"Information Segue"])
{   
    NSFetchRequest *request = [[NSFetchRequest alloc] init];
    NSEntityDescription *entity = [NSEntityDescription entityForName:@"Login" inManagedObjectContext:self.managedObjectContext];
    NSPredicate *predicate = [NSPredicate predicateWithFormat:@" ANY userid==%@ AND password==%@",_loginTextfield.text, _passwordTextField.text];
    [request setEntity:entity];
    [request setPredicate:predicate];
    NSError *anyError=Nil;
    NSArray *fetchedObjects = [self.managedObjectContext executeFetchRequest:request error:&anyError];
    if ([fetchedObjects count] )
    {
        useridentered = _loginTextfield.text;
        passwordentered = _passwordTextField.text;

        InformationTVC *informationTVC = segue.destinationViewController;
        informationTVC.managedObjectContext = self.managedObjectContext;             
    }
    else
    {
       /*  want to put my cancel the segue and remain in the login view */ 
    }
}

如果有人能指导我，那将是一个很大的帮助。

Answer 1

查看此线程: Conditional segue performed on tap on UITableViewCell

基本上不是将您的 segue 直接链接到按钮，而是将它放在 View Controller 之间，并将按钮链接到 IBAction，它将有条件地调用函数 performSegueWithIdentifier