ios - 从 UITextField 获取输入

Question

我正在为我的 iOS 应用程序编写程序化 UI，并且我有这两个 UITextField。当客户端打开应用程序时，他们将选择这两个字段并提供一些输入，之后，如何取消选择 UITextField？因为如果您点击或滚动屏幕上的其他地方，键盘会停留在屏幕上 - 它不会像预期的行为那样缩回。

所以我想我的问题是如何在没有nib 或storyboard 的情况下提交UITextField？

这是 viewDidLoad 的相关部分，有两个 UITextField:

UITextField *loginField = [[UITextField alloc] initWithFrame:mistarFrame];
loginField.backgroundColor = [UIColor clearColor];
loginField.textColor = [UIColor whiteColor];
loginField.font = [UIFont fontWithName:@"HelveticaNeue-Light" size:20];
loginField.borderStyle = UITextBorderStyleNone;
loginField.autocorrectionType = UITextAutocorrectionTypeNo;
loginField.autocapitalizationType = UITextAutocapitalizationTypeNone;
loginField.contentVerticalAlignment = UIControlContentVerticalAlignmentCenter;
loginField.attributedPlaceholder = [[NSAttributedString alloc] initWithString:@"Student ID" attributes:@{NSForegroundColorAttributeName: [UIColor whiteColor]}];
[header addSubview:loginField];

UITextField *passwordField = [[UITextField alloc] initWithFrame:CGRectMake(mistarFrame.origin.x, (mistarFrame.origin.y + iconHeight), mistarFrame.size.width, mistarFrame.size.height)];
passwordField.backgroundColor = [UIColor clearColor];
passwordField.textColor = [UIColor whiteColor];
passwordField.font = [UIFont fontWithName:@"HelveticaNeue-Light" size:20];
passwordField.borderStyle = UITextBorderStyleNone;
passwordField.autocorrectionType = UITextAutocorrectionTypeNo;
passwordField.autocapitalizationType = UITextAutocapitalizationTypeNone;
passwordField.contentVerticalAlignment = UIControlContentVerticalAlignmentCenter;
passwordField.attributedPlaceholder = [[NSAttributedString alloc] initWithString:@"Password" attributes:@{NSForegroundColorAttributeName: [UIColor whiteColor]}];
passwordField.secureTextEntry = YES;
[header addSubview:passwordField];

Answer 1

也可以按照UITextFieldDelegate协议(protocol)进行设置

loginField.delegate = self;
passwordField.delegate = self;

然后实现

- (BOOL)textFieldShouldReturn:(UITextField *)textField
{
    [textField resignFirstResponder];
    if ([loginField.text isEqualToString:@""] == NO && [passwordField.text isEqualToString:@""] == NO) {
        //submit...
    }
    return YES;
}

如果您想通过按键盘上的回车键提交。

这是一个示例实现文件...

#import "ViewController.h"

@interface ViewController () <UITextFieldDelegate>

@end

@implementation ViewController

- (void)viewDidLoad
{
    [super viewDidLoad];
UITextField *tf = [[UITextField alloc] initWithFrame:CGRectMake(10, 30, 100, 25)];
    [self.view addSubview:tf];
    tf.delegate = self;
}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

- (BOOL)textFieldShouldReturn:(UITextField *)textField
{
    [textField resignFirstResponder];
    if ([textField.text isEqualToString:@""] == NO) {
        NSLog(@"Submit");
    }
    return YES;
 }

@end