将touchupinside添加到以编程方式创建的按钮，并将NSDate提交到文本字段

Question

The problem I'm coming across is that I'm unsure how to add touchupinside to the below code for the save date button. I'm just trying to launch a UIDatePicker and submit a date into a text field, and then dismiss it.

So I don't know how to link this programmatically created button to the datePicker method. Not only that but, I haven't used UIDatePicker before, so reading this into a textfield I'm a bit fuzzy on. The text field is dateFieldText.

Once the user taps Save Date then the UIDatePicker should be dismissed.

Thanks for the help. This issue is a bit more complicated for me.

      - (void)textFieldDidBeginEditing:(UITextField *)sender
        {
            sender.delegate = self;
                if([sender isEqual:dateFieldText])
                {
                    UIBarButtonItem *doneButton = [[UIBarButtonItem alloc]
                                               initWithTitle:@"Save Date"
                                               style:UIBarButtonItemStyleDone
                                               target:self
                                               action:@selector(datePicker)];

                self.navigationItem.rightBarButtonItem = doneButton;

            }
            else{
                UIBarButtonItem *submitButton = [[UIBarButtonItem alloc]
                                               initWithTitle:@"Done"
                                               style:UIBarButtonItemStyleDone
                                               target:self
                                               action:@selector(datePicker)];
                self.navigationItem.rightBarButtonItem = submitButton;

            }  
        }


    -(IBAction)datePicker
    {
        UIDatePicker *datePicker = [[UIDatePicker alloc] init];
        datePicker.datePickerMode = UIDatePickerModeDateAndTime;
        [datePicker addTarget:self action:@selector(saveDate)  forControlEvents:UIControlEventValueChanged];
        [self.dateFieldText setInputView:datePicker];
    }

    // I haven't made the saveDate method yet...

Answer 1

You have a few things wired up incorrectly. You need to make the date picker the text field's inputView at the point you create the text field, not after the user taps a button that isn't added until the user puts focus on the text field.

You also don't need a Done button and a Save Date button. Either have a single Done button or have a Save and a Cancel button.

You are also going to need to implement the textFieldDidEndEditing delegate method to remove any buttons that you add.

Your saveDate method will need to update the text field's text with the currently selected date (after converting the date to a string with an NSDateFormatter ).

The action for your Done/Save/Cancel button(s) (whatever you end up doing) simply needs to call resignFirstResponder on the text field. This will dismiss the date picker. The button actions may also need to save off or revert the date's value as appropriate.