ios - 当调用状态在 ios objective c 中结束时无法更改 UIView 的 rect

Question

当调用状态将状态栏高度增加到 40 时，我需要调整 View 。我使用 - (void)application:(UIApplication *)application willChangeStatusBarFrame:(CGRect)newStatusBarFrame 使用 NSNotificationCenter

它在状态栏高度从 20 增加到 40 时起作用，但是当状态栏高度从 40 减少到 20 时 NSNotificationCenter 似乎没有发布通知，因为 UIView 框架没有分配给所需的 CGRectMake

我正在做一个旧项目，所以没有 Storyboard。

这是我尝试过的

在viewDidLoad中——

[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(statusBarChangedForBottmView:) name:@"STATUSBARCHANGED" object:self];

和方法

- (void) statusBarChangedForBottmView:(NSNotification *)notification
{
    NSDictionary *data = [notification userInfo];
    NSString *statusBar = [data valueForKey:@"frame"];
    NSLog(@"status bar in edit card = %@",statusBar);
    if ([statusBar isEqualToString:@"STATUS"])
    {
        if (STATUSBARINCREASED)
        {
            [self.bottomView setFrame:CGRectMake(0, self.view.frame.size.height-60, self.view.frame.size.width, 45)];
        }
        else
        {
            [self.bottomView setFrame:CGRectMake(0, self.view.frame.size.height-40, self.view.frame.size.width, 45)];
        }
    }

}

Answer 1

编辑:

确保您订阅了来自任何 对象的通知。即:

[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(statusBarChangedForBottmView:) name:@"STATUSBARCHANGED" object:nil]; // <-- object:nil

这不是发布通知的当前对象 (self)，而是您的 AppDelegate。

来自文档:

notificationSender

The object whose notifications the observer wants to receive; that is, only notifications sent by this sender are delivered to the observer. If you pass nil, the notification center doesn’t use a notification’s sender to decide whether to deliver it to the observer.

如果你得到这个工作，我仍然建议使用 UIApplicationWillChangeStatusBarFrameNotification，而不是从 - (void)application:(UIApplication *)application willChangeStatusBarFrame:(CGRect) 发布你自己的通知newStatusBarFrame.

---

我刚刚在一个新项目上进行了测试，使用 UIApplicationWillChangeStatusBarFrameNotification 效果非常好。

- (void)viewDidLoad {
    [super viewDidLoad];

    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(statusBarChanged:) name:UIApplicationWillChangeStatusBarFrameNotification object:nil];
}

- (void)statusBarChanged:(NSNotification *)notification
{
    NSDictionary *userInfo = notification.userInfo;
    NSValue *statusBarRectValue = userInfo[UIApplicationStatusBarFrameUserInfoKey];
    CGRect statusBarRect = [statusBarRectValue CGRectValue];
    NSLog(@"%@", NSStringFromCGRect(statusBarRect));
}

输出:

接听电话:

2014-10-09 17:53:31.407 test-so[14775:8742949] {
    UIApplicationStatusBarFrameUserInfoKey = "NSRect: {{0, 0}, {375, 40}}";
}

通话结束:

2014-10-09 17:53:35.881 test-so[14775:8742949] {
    UIApplicationStatusBarFrameUserInfoKey = "NSRect: {{0, 0}, {375, 20}}";
}