Question

我想让textField.enabled开启和关闭但无论textField如何，switch.on都无法修改我该如何解决？

UISwitch* switch = [[UISwitch alloc]initWithFrame:CGRectMake(140, 293, 60, 25)];
[self.view addSubview:switch];

UITextField* textField = [[UITextField alloc]initWithFrame:CGRectMake(200, 293, 100, 30)];
textField.delegate = self;
[self.view addSubview:textField];

if (switch.on == YES) {
    textField.enabled = YES;
} else {
    textField.enabled = NO;
}

谢谢。

Answer 1

您需要将目标添加到UISwitch

-(void)viewDidLoad
{
    [super viewDidLoad];

    UISwitch* switch = [[UISwitch alloc]initWithFrame:CGRectMake(140, 293, 60, 25)];
    [switch addTarget:self action:@selector(didChangeSwitch:) forControlEvents:UIControlEventValueChanged];
    [self.view addSubview:switch];

    UITextField* textField = [[UITextField alloc]initWithFrame:CGRectMake(200, 293, 100, 30)];
    textField.delegate = self;
    [self.view addSubview:textField];
    self.textField = textField;

}

-(void)didChangeSwitch:(UISwitch *)sender
{ 
    self.textField.enabled = switch.on;
}

Answer 2

顺便说一下，你可以替换

if (switch.on == YES) {
    textField.enabled = YES;
} else {
    textField.enabled = NO;
}

与

textField.enabled=switch.on;

<小时/> 另一种方法是创建计时器：

NSTimer *timer=[NSTimer scheduledTimerWithTimeInterval:0.1
    target:self selector:@selector(yourSelector:) userInfo:nil repeats:YES];

声明选择器：

-(void)yourSelector:(NSTimer*)timer
{
textField.enabled=switch.on
}

Answer 3

更改开关时需要监听：

[switch addTarget:self action:@selector(switched:) forControlEvents:UIControlEventValueChanged];

然后：

- (void)switched:(UISwitch *)switch {
    if (switch.on == YES) {
        textField.enabled = YES;
    } else {
        textField.enabled = NO;
    }
}

或更简单：

- (void)switched:(UISwitch *)switch {
    textField.enabled = switch.on;
}

根据UISwitch.on，UITextField.enabled为Yes或No

3 个答案: