Question

我的UINavigationBar中有一个UIBarButtonItem。有一张明星的照片（白色的）。如果用户在明星上陈词滥调我已经设定明星的色调颜色为黄色，作为最喜欢的颜色。如果用户点击白星一次，它会改变颜色，然后用户关闭应用程序。如果他真的点击它，我想仍然选择明星。它有效，但在再次运行后不要保存。有什么想法吗？

static UIBarButtonItem *barb1;
@interface ViewControllerDetail (){
    BOOL kokos;
}

-(void)changestarr{
if (kokos) {
            [barb1 setTintColor:[UIColor whiteColor]];
            kokos = NO;

        } else {
            [barb1 setTintColor:[UIColor yellowColor]];
            kokos = YES;
            prefs = [NSUserDefaults standardUserDefaults];
            [prefs setObject:[UIColor yellowColor] forKey:@"yess"];
            [prefs synchronize];
            NSString *message = @"You got it.";

            UIAlertView *toast = [[UIAlertView alloc] initWithTitle:nil
                                                            message:message
                                                           delegate:nil
                                                  cancelButtonTitle:nil
                                                  otherButtonTitles:nil, nil];
            [toast show];

            int duration = 1.7;

            dispatch_after(dispatch_time(DISPATCH_TIME_NOW, duration * NSEC_PER_SEC), dispatch_get_main_queue(), ^{
                [toast dismissWithClickedButtonIndex:0 animated:YES];

            });
        }}

viewDidLoad中

- (void)viewDidLoad
    {
        [super viewDidLoad];
        kokos = NO;
        barb1 =[[UIBarButtonItem alloc]initWithImage:[UIImage imageNamed:@"star.png"]
                                                                style:UIBarButtonItemStyleDone
                                                               target:self
                                                               action:@selector(changestarr)];

         barb2=[[UIBarButtonItem alloc]initWithImage:[UIImage imageNamed:@"final.png"]
                                                                style:UIBarButtonItemStyleDone
                                                               target:self
                                                             action:@selector(showfinal)];
        [barb1 setTintColor:[UIColor whiteColor]];

        self.navigationItem.rightBarButtonItems = [[NSArray alloc] initWithObjects:barb1, barb2, nil];

    }

Answer 1

首先，您应该设置首次关闭默认值。

-(void)setDefaults
{
 NSDictionary *dictionary = @{ @"BarButtonColor" : @1 }; // where 1 is white

 [[NSUserDefaults standardUserDefaults] registerDefaults:dictionary]; 

}

现在在视图控制器的init方法中调用 - （void）setDefaults。然后将 - （void）viewDidLoad更改为以下内容。

- (void)viewDidLoad
{
    [super viewDidLoad];

 // If you do not want to set defaults in init

 if ([[NSUserDefaults standardUserDefaults] integerForKey: @"BarButtonColor"] == 0) {
     [[NSUserDefaults standardUserDefaults] setInteger:1 forKey: @"BarButtonColor"];
     }



    kokos = NO; // Remove
    barb1 =[[UIBarButtonItem alloc]initWithImage:[UIImage imageNamed:@"star.png"]
                                                            style:UIBarButtonItemStyleDone
                                                           target:self
                                                           action:@selector(changestarr)];

     barb2=[[UIBarButtonItem alloc]initWithImage:[UIImage imageNamed:@"final.png"]
                                                            style:UIBarButtonItemStyleDone
                                                           target:self
                                                         action:@selector(showfinal)];
    // changes
    NSInteger color = [[NSUserDefaults standardUserDefaults] integerForKey: @"BarButtonColor"];

    if (color == 1) {
    [barb1 setTintColor:[UIColor whiteColor]];
    } else if (colour == 2) {
    [barb1 setTintColor:[UIColor yellowColor]];
    }

    // finished changes

    self.navigationItem.rightBarButtonItems = [[NSArray alloc] initWithObjects:barb1, barb2, nil];

}

然后最后改变 - （void）changstarr到下面的

-(void)changestarr{

NSInteger color = [[NSUserDefaults standardUserDefaults] integerForKey: @"BarButtonColor"];

if (color == 2) {
        [barb1 setTintColor:[UIColor whiteColor]];
        [[NSUserDefaults standardUserDefaults] setInteger:1 forKey:@"BarButtonColor"]];

    } else if (color == 1) {
        [barb1 setTintColor:[UIColor yellowColor]];
        [[NSUserDefaults standardUserDefaults] setInteger:2 forKey:@"BarButtonColor"]];
        NSString *message = @"You got it.";

        UIAlertView *toast = [[UIAlertView alloc] initWithTitle:nil
                                                        message:message
                                                       delegate:nil
                                              cancelButtonTitle:nil
                                              otherButtonTitles:nil, nil];
        [toast show];

        int duration = 1.7;

        dispatch_after(dispatch_time(DISPATCH_TIME_NOW, duration * NSEC_PER_SEC), dispatch_get_main_queue(), ^{
            [toast dismissWithClickedButtonIndex:0 animated:YES];

        });
    }}

如果应用程序意外终止，您可能需要进行错误检查。

使用NSUserDefaults进行TintColor更改

1 个答案: