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我正在構建簡單的登錄屏幕。我創建了一些動態字段，將一個監聽器附加到按鈕上，但是我無法點擊這些元素來開始輸入我的用戶名和密碼。如果按Tab鍵，焦點會進入輸入，但我無法使用該點擊。我究竟做錯了什麼？動態創建的字段和按鈕在iOS中不可點擊
請參閱下面的代碼和屏幕截圖。以紅色突出顯示的區域不可點擊，並且我已啓用輔助功能檢查器。它從不顯示我的任何元素。
@interface PRLoginController() <UITextFieldDelegate>
@property (nonatomic) UIView *inputView;
@property (nonatomic) UITextField *usernameTextField;
@property (nonatomic) UITextField *passwordTextField;
@property (nonatomic) UIButton *loginButton;
@property (nonatomic) UIButton *cancelButton;
- (void)doLogin;
- (void)doCancel;
- (void)initializeUserInput;
+ (UIViewController *)getTopViewController;
@end
@implementation PRLoginController
- (void)viewDidLoad {
[super viewDidLoad];
self.view.backgroundColor = [UIColor whiteColor];
self.navigationItem.title = @"Login";
self.navigationItem.backBarButtonItem = [[UIBarButtonItem alloc] initWithTitle:@"Cancel" style:UIBarButtonItemStylePlain target:nil action:nil];
[self initializeUserInput];
}
- (void)initializeUserInput {
UIView *inputView = [[UIView alloc] init];
inputView.translatesAutoresizingMaskIntoConstraints = NO;
CGFloat inputViewMargin = 50.0;
CGFloat inputElementTopMargin = 20.0;
[self.view addSubview:inputView];
[self.view addConstraints:@[
[NSLayoutConstraint constraintWithItem:inputView attribute:NSLayoutAttributeCenterX relatedBy:NSLayoutRelationEqual toItem:self.view attribute:NSLayoutAttributeCenterX multiplier:1.0 constant:0.0],
[NSLayoutConstraint constraintWithItem:inputView attribute:NSLayoutAttributeCenterY relatedBy:NSLayoutRelationEqual toItem:self.view attribute:NSLayoutAttributeCenterY multiplier:1.0 constant:0.0],
[NSLayoutConstraint constraintWithItem:inputView attribute:NSLayoutAttributeLeading relatedBy:NSLayoutRelationEqual toItem:self.view attribute:NSLayoutAttributeLeading multiplier:1.0 constant:inputViewMargin],
[NSLayoutConstraint constraintWithItem:inputView attribute:NSLayoutAttributeTrailing relatedBy:NSLayoutRelationEqual toItem:self.view attribute:NSLayoutAttributeTrailing multiplier:1.0 constant:-inputViewMargin]
]];
_inputView = inputView;
CGFloat textFieldHeight = 30.0;
UITextField *topTextField = [[UITextField alloc] init];
topTextField.translatesAutoresizingMaskIntoConstraints = NO;
[inputView addSubview:topTextField];
[inputView addConstraints:@[
[NSLayoutConstraint constraintWithItem:topTextField attribute:NSLayoutAttributeTop relatedBy:NSLayoutRelationEqual toItem:inputView attribute:NSLayoutAttributeTop multiplier:1.0 constant:0],
[NSLayoutConstraint constraintWithItem:topTextField attribute:NSLayoutAttributeLeading relatedBy:NSLayoutRelationEqual toItem:inputView attribute:NSLayoutAttributeLeading multiplier:1.0 constant:0],
[NSLayoutConstraint constraintWithItem:topTextField attribute:NSLayoutAttributeTrailing relatedBy:NSLayoutRelationEqual toItem:inputView attribute:NSLayoutAttributeTrailing multiplier:1.0 constant:0],
[NSLayoutConstraint constraintWithItem:topTextField attribute:NSLayoutAttributeHeight relatedBy:NSLayoutRelationEqual toItem:nil attribute:NSLayoutAttributeHeight multiplier:1.0 constant:textFieldHeight],
]];
UITextField *bottomTextField = [[UITextField alloc] init];
bottomTextField.translatesAutoresizingMaskIntoConstraints = NO;
[inputView addSubview:bottomTextField];
[inputView addConstraints:@[
[NSLayoutConstraint constraintWithItem:bottomTextField attribute:NSLayoutAttributeTop relatedBy:NSLayoutRelationEqual toItem:topTextField attribute:NSLayoutAttributeBottom multiplier:1.0 constant:inputElementTopMargin],
[NSLayoutConstraint constraintWithItem:bottomTextField attribute:NSLayoutAttributeLeading relatedBy:NSLayoutRelationEqual toItem:inputView attribute:NSLayoutAttributeLeading multiplier:1.0 constant:0.0],
[NSLayoutConstraint constraintWithItem:bottomTextField attribute:NSLayoutAttributeTrailing relatedBy:NSLayoutRelationEqual toItem:inputView attribute:NSLayoutAttributeTrailing multiplier:1.0 constant:0.0],
[NSLayoutConstraint constraintWithItem:bottomTextField attribute:NSLayoutAttributeHeight relatedBy:NSLayoutRelationEqual toItem:nil attribute:NSLayoutAttributeHeight multiplier:1.0 constant:textFieldHeight]
]];
topTextField.borderStyle = UITextBorderStyleRoundedRect;
bottomTextField.borderStyle = UITextBorderStyleRoundedRect;
topTextField.autocapitalizationType = UITextAutocapitalizationTypeNone;
bottomTextField.autocapitalizationType = UITextAutocapitalizationTypeNone;
topTextField.autocorrectionType = UITextAutocorrectionTypeNo;
bottomTextField.autocorrectionType = UITextAutocorrectionTypeNo;
topTextField.returnKeyType = UIReturnKeyDone;
bottomTextField.returnKeyType = UIReturnKeyDone;
topTextField.delegate = self;
bottomTextField.delegate = self;
topTextField.placeholder = @"Username";
bottomTextField.placeholder = @"Password";
_usernameTextField = topTextField;
_passwordTextField = bottomTextField;
UIButton *leftButton = [UIButton buttonWithType:UIButtonTypeCustom];
leftButton.translatesAutoresizingMaskIntoConstraints = NO;
[inputView addSubview:leftButton];
[inputView addConstraints:@[
[NSLayoutConstraint constraintWithItem:leftButton attribute:NSLayoutAttributeBottom relatedBy:NSLayoutRelationEqual toItem:inputView attribute:NSLayoutAttributeBottom multiplier:1.0 constant:150],
[NSLayoutConstraint constraintWithItem:leftButton attribute:NSLayoutAttributeLeading relatedBy:NSLayoutRelationEqual toItem:inputView attribute:NSLayoutAttributeLeading multiplier:1.0 constant:0.0],
[NSLayoutConstraint constraintWithItem:leftButton attribute:NSLayoutAttributeTrailing relatedBy:NSLayoutRelationEqual toItem:inputView attribute:NSLayoutAttributeCenterX multiplier:1.0 constant:-5.0],
]];
UIButton *rightButton = [UIButton buttonWithType:UIButtonTypeCustom];
rightButton.translatesAutoresizingMaskIntoConstraints = NO;
[inputView addSubview:rightButton];
[inputView addConstraints:@[
[NSLayoutConstraint constraintWithItem:rightButton attribute:NSLayoutAttributeBottom relatedBy:NSLayoutRelationEqual toItem:inputView attribute:NSLayoutAttributeBottom multiplier:1.0 constant:150],
[NSLayoutConstraint constraintWithItem:rightButton attribute:NSLayoutAttributeTrailing relatedBy:NSLayoutRelationEqual toItem:inputView attribute:NSLayoutAttributeTrailing multiplier:1.0 constant:0.0],
[NSLayoutConstraint constraintWithItem:rightButton attribute:NSLayoutAttributeLeading relatedBy:NSLayoutRelationEqual toItem:inputView attribute:NSLayoutAttributeCenterX multiplier:1.0 constant:5.0],
]];
leftButton.backgroundColor = [UIColor grayColor];
rightButton.backgroundColor = leftButton.backgroundColor;
leftButton.layer.cornerRadius = 4.0;
rightButton.layer.cornerRadius = leftButton.layer.cornerRadius;
[leftButton setTitle:@"Login" forState:UIControlStateNormal];
[rightButton setTitle:@"Cancel" forState:UIControlStateNormal];
[leftButton addTarget:self action:@selector(doLogin) forControlEvents:UIControlEventTouchUpInside];
[rightButton addTarget:self action:@selector(doCancel) forControlEvents:UIControlEventTouchUpInside];
_loginButton = leftButton;
_cancelButton = rightButton;
}
編輯
我已刪除了手勢識別器，但沒有幫助。點擊ui不會做任何事情。我對這個處理程序不是特別感興趣，它是從不同的角度複製的，但刪除它也沒有幫助。
爲什麼在根視圖上有一個輕擊手勢識別器？ – NRitH
@NRitH輕觸識別器似乎是將文本框中的輕擊鍵盤關閉。 @ caiocpricci2你可以在識別器處理程序中添加一個日誌，我想它是攔截觸摸並且不允許通過文本字段。點擊文本字段，查看點擊識別器日誌是否被觸發。你也不需要添加'inputView'並設置它的約束兩次。 –
嘗試移除輕擊識別器，然後查看您是否獲得了期望的文本字段行爲......如果是這樣，我們可以查看「UIGestureRecignizerDelegate」來正確解決它。 –