如何检测UISwitch是否打开/关闭？

Question

我试图检测UIS开关何时打开/关闭

// .h
IBOutlet UISwitch *privateSwitch;
@property (nonatomic, retain) IBOutlet UISwitch *privateSwitch;

//.m
@synthesize privateSwitch;
privateSwitch = [[UISwitch alloc] init];
howToDisplay = @"no";

// In my cellForRowsAtIndexPath
UISwitch *privateSwitch = [[UISwitch alloc] initWithFrame:CGRectMake(199, 8, 0, 0)];
[privateSwitch addTarget:self action:@selector(switchToggled:) forControlEvents: UIControlEventTouchUpInside];
[cell.contentView addSubview:privateSwitch];

if ([howToDisplay isEqualToString:@"no"]) {
    [privateSwitch setOn:NO animated:NO];
} else {
    [privateSwitch setOn:YES animated:NO];
}

- (void) switchToggled:(id)sender {

if ([privateSwitch isOn]) {
NSLog(@"its on!");
howToDisplay = @"yes";
[formDataTwo removeAllObjects];
[formTableView reloadData];
[privateSwitch setOn:YES animated:YES];
} else {
NSLog(@"its off!");
howToDisplay = @"no";
[formDataTwo removeAllObjects];
[formDataTwo addObject:@"Facebook"];
[formDataTwo addObject:@"Twitter"];
[formDataTwo addObject:@"Flickr"];
[formDataTwo addObject:@"Tumblr"];
[formDataTwo addObject:@"Email"];
[formDataTwo addObject:@"MMS"];

[formTableView reloadData];
[privateSwitch setOn:NO animated:YES];
}

}

但是,当我打开它时,它会说它已关闭.是什么赋予了？

谢谢.

Answer 1

在您的cellForRowsAtIndexPath方法中,您声明一个UISwitch *privateSwitch隐藏实例变量的局部变量privateSwitch.

在您的switchToggled:操作中,您正在使用实例变量来测试交换机的状态,而不是在其中声明的状态cellForRowAtIndexPath.你可以使用这样的sender参数:

- (void) switchToggled:(id)sender {
    UISwitch *mySwitch = (UISwitch *)sender;
    if ([mySwitch isOn]) {
        NSLog(@"its on!");
    } else {
        NSLog(@"its off!");
    }
}

PS:我会用UIControlEventValueChanged而不是UIControlEventTouchUpInside.