iPhone 在 UITextField touch 上显示日期选择器

Question

我关注了这个帖子:datepicker by clicking on textfield

我导入了以下两个协议(protocol):

@interface ViewController : UIViewController<UIActionSheetDelegate, UITextFieldDelegate> {

然后，在实现中，我使用以下内容:

- (void)viewDidLoad {

    textField.delegate = self;

[super viewDidLoad] }

最后，我放置了实际代码来显示日期选择器(来自线程)。我还在 IB 中将其全部链接起来。

    //Date Picker
- (void)textFieldDidBeginEditing:(UITextField *)aTextField{    
    [aTextField resignFirstResponder];  

    pickerViewPopup = [[UIActionSheet alloc] initWithTitle:nil delegate:self cancelButtonTitle:nil destructiveButtonTitle:nil otherButtonTitles:nil];  

    UIDatePicker *pickerView = [[UIDatePicker alloc] initWithFrame:CGRectMake(0, 44, 0, 0)];  
    pickerView.datePickerMode = UIDatePickerModeDate;  
    pickerView.hidden = NO;  
    pickerView.date = [NSDate date];  

    UIToolbar *pickerToolbar = [[UIToolbar alloc] initWithFrame:CGRectMake(0, 0, 320, 44)];  
    pickerToolbar.barStyle = UIBarStyleBlackOpaque;  
    [pickerToolbar sizeToFit];  

    NSMutableArray *barItems = [[NSMutableArray alloc] init];  

    UIBarButtonItem *flexSpace = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemFlexibleSpace target:self action:nil];  
    [barItems addObject:flexSpace];  

    UIBarButtonItem *doneBtn = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemDone target:self action:@selector(doneButtonPressed:)];  
    [barItems addObject:doneBtn];  

    UIBarButtonItem *cancelBtn = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemCancel target:self action:@selector(cancelButtonPressed:)];  
    [barItems addObject:cancelBtn];  

    [pickerToolbar setItems:barItems animated:YES];  

    [pickerViewPopup addSubview:pickerToolbar];  
    [pickerViewPopup addSubview:pickerView];  
    [pickerViewPopup showInView:self.view];  
    [pickerViewPopup setBounds:CGRectMake(0,0,320, 464)];    
}  

-(void)doneButtonPressed:(id)sender{  
    //Do something here here with the value selected using [pickerView date] to get that value  
        [pickerViewPopup dismissWithClickedButtonIndex:1 animated:YES];  
}  

-(void)cancelButtonPressed:(id)sender{  
    [pickerViewPopup dismissWithClickedButtonIndex:1 animated:YES];  
}  

但是，当我单击 UITextField 时，我得到:

我做错了什么？

Answer 1

您可以使用UITextField 输入 View 属性。只需在代码中分配初始化一个常规的 UIDatePicker 并将其分配给文本字段的 inputView 即可。执行此操作后，将显示 UIPickerView 而不是键盘。如果您需要任何代码，请随时询问:)

编辑:代码

您首先将 textField 与 IB 连接起来

@interface myViewController <UITextFieldDelegate>
@property (nonatomic,weak) IBOutlet UITextField *myTextField;
@end 

实现中

UIDatePicker *datePicker = [[UIDatePicker alloc]init];
[datePicker setDate:[NSDate date]];
[datePicker addTarget:self action:@selector(updateTextField:) forControlEvents:UIControlEventValueChanged];
if (@available(iOS 13.4, *)) {
    [datePicker setPreferredDatePickerStyle:UIDatePickerStyleWheels];
}       
[self.myTextField setInputView:datePicker];

当您点击 textField 时，将会弹出一个 UIDatePicker。请注意我添加到 datePicker 的操作。

[datePicker addTarget:self action:@selector(updateTextField:) forControlEvents:UIControlEventValueChanged];

要在用户每次在选择器中滚动时更新 textField，您只需在 viewController 中的某处实现 updateTextField 方法

-(void)updateTextField:(id)sender
{
  UIDatePicker *picker = (UIDatePicker*)self.myTextField.inputView;
  self.myTextField.text = [NSString stringWithFormat:@"%@",picker.date];
}

使用最后一个方法，每次用户旋转选择器时，文本字段都会更新!

• 您可以使用 NSDateFormatter 来改进字符串的输出。