UILabel不显示inputView
我将使用UILabel来允许用户使用UIDatePickerselectdate。
为此，我创build了一个覆盖inputView和inputAccessoryView属性的UILabel子类，使它们可写; 我还实现了 – （BOOL）canBecomeFirstResponder和 – （BOOL）isUserInteractionEnabled方法返回YES。 然后，我将UIDatePIcker的一个实例分配给了inputView属性。
在这一点上，我的期望是，当标签被点击时，UIDatePicker应该出现，但没有任何反应。
任何帮助？
这是代码：
YPInteractiveUILabel.h @interface YPInteractiveUILabel : UILabel @property (readwrite) UIView *inputView; @property (readwrite) UIView *inputAccessoryView; - (BOOL) canBecomeFirstResponder; - (BOOL) isUserInteractionEnabled; @end YPInteractiveUILabel.h #import "YPInteractiveUILabel.h" @implementation YPInteractiveUILabel - (id)initWithCoder:(NSCoder *)aDecoder { self = [super initWithCoder:aDecoder]; if (self) { UIDatePicker *datePicker = [[UIDatePicker alloc] init]; [self setInputView:datePicker]; } return self; } - (BOOL)isUserInteractionEnabled { return YES; } - (BOOL)canBecomeFirstResponder { return YES; } @end 这样的事情呢？ 而不是子类的标签，只需添加一个手势识别器，并调出水龙头识别器的处理程序中的select器。 在选取器的操作方法中，填充标签并closures选取器。 这个例子可以工作，但是你可能想添加一些animation来使它看起来更好：
- (void)viewDidLoad { [super viewDidLoad]; self.label.userInteractionEnabled = YES; UITapGestureRecognizer *tapper = [[UITapGestureRecognizer alloc]initWithTarget:self action:@selector(launchPicker:)]; [self.label addGestureRecognizer:tapper]; } -(void)launchPicker:(UITapGestureRecognizer *) tapper { UIDatePicker *picker = [[UIDatePicker alloc] initWithFrame:CGRectMake(5, 150, 300, 200)]; [picker addTarget:self action:@selector(updateLabel:) forControlEvents:UIControlEventValueChanged]; [self.view addSubview:picker]; } -(IBAction)updateLabel:(UIDatePicker *)sender { self.label.text = [NSString stringWithFormat:@"%@",sender.date ]; [sender removeFromSuperview]; }
您可以只用ovveride inputView getter方法，就像Apple文档中所解释的那样：
- (UIView *)inputView { return myInputView; } - (BOOL)canBecomeFirstResponder { return YES; }
然后添加一个手势或一个button来调用becomeFirstResponder：
- (void)showInputView:(id)sender { [self becomeFirstResponder]; }
由于build议（特别是从NeverBe的评论和rdelmar提出的答案），我在我的代码中find了问题。 简而言之，为了显示input标签，需要用户点击标签时调用becomeFirstResponder方法。
在UILabel子类实现更正之后（头文件保持不变）：
@implementation YPInteractiveUILabel - (id)initWithCoder:(NSCoder *)aDecoder { self = [super initWithCoder:aDecoder]; if (self) { UIDatePicker *datePicker = [[UIDatePicker alloc] init]; [self setInputView:datePicker]; UITapGestureRecognizer *tapper = [[UITapGestureRecognizer alloc]initWithTarget:self action:@selector(launchPicker:)]; [self addGestureRecognizer:tapper]; } return self; } - (BOOL)isUserInteractionEnabled { return YES; } - (BOOL)canBecomeFirstResponder { return YES; } -(void)launchPicker:(UITapGestureRecognizer *) tapper { [self becomeFirstResponder]; } @end
UILabel + UIDatePicker – 带完成button的Swift版本。
import UIKit class DatePickerLabel: UILabel { private let _inputView: UIView? = { let picker = UIDatePicker() return picker }() private let _inputAccessoryToolbar: UIToolbar = { let toolBar = UIToolbar() toolBar.barStyle = UIBarStyle.Default toolBar.translucent = true toolBar.sizeToFit() return toolBar }() override var inputView: UIView? { return _inputView } override var inputAccessoryView: UIView? { return _inputAccessoryToolbar } required init?(coder aDecoder: NSCoder) { super.init(coder: aDecoder) let doneButton = UIBarButtonItem(title: "Done", style: UIBarButtonItemStyle.Plain, target: self, action: #selector(doneClick)) let spaceButton = UIBarButtonItem(barButtonSystemItem: UIBarButtonSystemItem.FlexibleSpace, target: nil, action: nil) _inputAccessoryToolbar.setItems([ spaceButton, doneButton], animated: false) let tapRecognizer = UITapGestureRecognizer(target: self, action: #selector(launchPicker)) self.addGestureRecognizer(tapRecognizer) } override func canBecomeFirstResponder() -> Bool { return true } @objc private func launchPicker() { becomeFirstResponder() } @objc private func doneClick() { resignFirstResponder() } }
我知道这是一个古老的问题，但这可能仍然是有用的人。
还有另一种方法可以解决这个问题 – 不需要用手势识别器来使事情复杂化。
GTPDateLabel.h
@interface GTPDateLabel : UILabel @property (readonly, retain) UIView *inputView; @end
GTPDateLabel.m
#import "GTPDateLabel.h" @implementation GTPDateLabel @synthesize inputView = _inputView; - (id)initWithFrame:(CGRect)frame { self = [super initWithFrame:frame]; if (self) { self.userInteractionEnabled = YES; } return self; } - (id)initWithCoder:(NSCoder *)aDecoder { self = [super initWithCoder:aDecoder]; if (self) { self.userInteractionEnabled = YES; } return self; } -(void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event { [super touchesEnded:touches withEvent:event]; [self becomeFirstResponder]; } - (BOOL)canBecomeFirstResponder { return YES; } -(UIView *)inputView { if (!_inputView) { UIDatePicker *datePicker = [[UIDatePicker alloc] init]; _inputView = datePicker; } return _inputView; } @end
请注意，你也应该设置delegate并在自定义的UIPicker也dataSource情况下…