Uialertview 文本到 NSMutableArray，ios 4.3

Question

我一直在尝试将文本输入从alertview文本字段复制到我稍后将使用的NSMutableArray，alertview弹出，我将输入输入到文本字段，但是当我按“确定”时，警报视图消失，但不将文本复制到我的可变数组，

这是我的 这里的代码

-(IBAction)add:(UIButton *)sender
{
    addCustomStand = [[NSMutableArray alloc] init];
    UIAlertView* dialog = [[UIAlertView alloc] initWithTitle:@"Enter a Stand Location"
                                                     message:@"  "   
                                                    delegate:self 
                                           cancelButtonTitle:@"Cancel"
                                           otherButtonTitles:@"OK", nil];

    UITextField *nameField = [[UITextField alloc] 
                              initWithFrame:CGRectMake(20.0, 45.0, 245.0, 25.0)];
    [nameField setBackgroundColor:[UIColor whiteColor]];
     nameField.text = @"";
    [dialog addSubview:nameField];

    if ([nameField text]){
        NSLog(@"Name Field %@ ",nameField.text);
        [addCustomStand addObject:nameField.text];
    }

    [nameField release];
    [dialog show];
    [dialog release];   
}

- (void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex
{
    NSString *title = [alertView buttonTitleAtIndex:buttonIndex];

    if([title isEqualToString:@"OK"])
    {
        NSLog(@"Button 1 was selected.");
        NSLog(@"StandLocations %@ ",addCustomStand);
    }
}

是我在日志屏幕上的输出

2012-02-07 20:26:57.315 Avicii[1399:b603] Name Field  
2012-02-07 20:26:59.720 Avicii[1399:b603] Button 1 was selected.
2012-02-07 20:26:59.721 Avicii[1399:b603] StandLocations (
    ""
)

任何人都可以帮助该代码有什么问题吗？

Answer 1

这是因为当您将其添加到 [addCustomStand addObject:nameField.text]; 中时，[nameField text] 还没有用户输入的值，

因此将您的添加更改为数组UIAlertView 委托方法。

-(IBAction)add:(UIButton *)sender
{
    addCustomStand = [[NSMutableArray alloc] init];
    UIAlertView* dialog = [[UIAlertView alloc] initWithTitle:@"Enter a Stand Location"
                                                     message:@"  "   
                                                    delegate:self 
                                           cancelButtonTitle:@"Cancel"
                                           otherButtonTitles:@"OK", nil];

    UITextField *nameField = [[UITextField alloc] 
                              initWithFrame:CGRectMake(20.0, 45.0, 245.0, 25.0)];
    [nameField setBackgroundColor:[UIColor whiteColor]];
    nameField.text = @"";
    // Note at this line
    nameField.tag = 100; 
    //
    [dialog addSubview:nameField];

    [nameField release];
    [dialog show];
    [dialog release];   
}

- (void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex
{
    NSString *title = [alertView buttonTitleAtIndex:buttonIndex];

    if([title isEqualToString:@"OK"])
    {
        // Note at this line
        UITextField* nameField = (UITextField *)[alertView viewWithTag:100];
        [addCustomStand addObject:nameField.text];
        //
        NSLog(@"Button 1 was selected.");
        NSLog(@"StandLocations %@ ",addCustomStand);
    }
}

Answer 2

在显示警报对话框之前，您需要将 nameField.text 添加到 addCustomStand 数组中。将其添加到数组时，该值是一个空字符串。

相反，您需要在 clickedButtonAtIndex: 方法期间将值复制到数组中，方法如下：

- (void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex
{
    NSString *title = [alertView buttonTitleAtIndex:buttonIndex];

    if([title isEqualToString:@"OK"])
    {
        NSString *location;
        UIView *view;
        for (view in [alertView subviews]) {

            if ([view isKindOfClass:[UITextField class]]) {
                location = [(UITextField*)view text];
            }
        }

        if (location) {
            [addCustomStand addObject:location];
        }
    }
}