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copied!<p>Showing a <code>UIDatePicker</code> for the <code>inputView</code> of a <code>UITextField</code> is relatively hard compared to showing a keyboard, but relatively easy compared to the trouble you've had.</p> <p>One of the first problems I noticed with your code, and it's a very common problem with those new to iOS/Mac development, is that you are attempting to set the property of an object that doesn't exist yet. Putting "<code>self.dueDate.inputView = datePicker;</code>" in your <code>initWithNibName:bundle:</code> will not work because the view has not yet loaded, and <code>dueDate</code> is part of your view. In objective-c an object is instantiated with alloc & init. Init is the first real method call to any object. At this point in your view controller's life the view has not been created yet. The method call where <code>self.dueDate.inputView = datePicker;</code> belongs is in the <code>viewDidLoad</code> method. It is called exactly when it sounds like it's called, and your <code>dueDate</code> property will be properly loaded at that point. There is no need to use a custom subclass of <code>UITextField</code> to display a date picking view for for your text field. Here is a very basic example of a custom input view class:</p> <p>ExampleBasicDateInputView.h:</p> <pre><code>#import <UIKit/UIKit.h> @interface ExampleBasicDateInputView : UIView @property (strong,nonatomic) UIDatePicker *datePicker; @end </code></pre> <p>ExampleBasicDateInputView.m:</p> <pre><code>#import "ExampleBasicDateInputView.h" @implementation ExampleBasicDateInputView{ UITextField *_inputField; // ivar to store the textfield currently being edited } @synthesize datePicker = _datePicker; // TARGET METHODS -(void)pickerValueChanged:(UIDatePicker *)picker{ _inputField.text = self.datePicker.date.description; // set text to date description } -(void)viewDoubleTapped:(UITapGestureRecognizer *)tapGR{ [_inputField resignFirstResponder]; // upon double-tap dismiss picker } -(void)textFieldBeganEditing:(NSNotification *)note{ _inputField = note.object; // set ivar to current first responder } -(void)textFieldEndedEditing:(NSNotification *)note{ _inputField = nil; // the first responder ended editing CRITICAL:avoids retain cycle } // INITI METHODS -(void)initializationCodeMethod{ _datePicker = [[UIDatePicker alloc] initWithFrame:CGRectMake(0, 0, 320, 0)];// All pickers have preset height self.bounds = _datePicker.frame; // Make our view same size as picker [self addSubview:_datePicker]; [_datePicker addTarget:self action:@selector(pickerValueChanged:) forControlEvents:UIControlEventValueChanged]; // register to be notified when the value changes // As an example we'll use a tap gesture recognizer to dismiss on a double-tap UITapGestureRecognizer *tapGR = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(viewDoubleTapped:)]; tapGR.numberOfTapsRequired = 2; // Limit to double-taps [self addGestureRecognizer:tapGR]; NSNotificationCenter *center = [NSNotificationCenter defaultCenter]; [center addObserver:self selector:@selector(textFieldBeganEditing:) name:UITextFieldTextDidBeginEditingNotification object:nil]; // Ask to be informed when any textfield begins editing [center addObserver:self selector:@selector(textFieldEndedEditing:) name:UITextFieldTextDidEndEditingNotification object:nil]; // Ask to be informed when any textfield ends editing } -(id)init{ if ((self = [super init])){ [self initializationCodeMethod]; } return self; } -(id)initWithFrame:(CGRect)frame{ if ((self = [super initWithFrame:frame])){ [self initializationCodeMethod]; } return self; } -(id)initWithCoder:(NSCoder *)aDecoder{ if ((self = [super initWithCoder:aDecoder])){ [self initializationCodeMethod]; } return self; } -(void)dealloc{ [[NSNotificationCenter defaultCenter] removeObserver:self name:UITextFieldTextDidBeginEditingNotification object:nil]; [[NSNotificationCenter defaultCenter] removeObserver:self name:UITextFieldTextDidEndEditingNotification object:nil]; } @end </code></pre> <p>Then in view did load you would use this class like this:</p> <pre><code>ExampleBasicDateInputView *dateEntryView = [[ExampleBasicDateInputView alloc] init]; self.dueDate.inputView = datePickerView; </code></pre> <p>And as you see in the <code>.h</code> file we've exposed the date picker instance as a property so you can set the style. etc. like so:</p> <pre><code>dateEntryView.datePicker.datePickerMode = UIDatePickerModeDate; </code></pre> <p>Obviously this is a very basic example, but I think it shows what can be done.</p>

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