iphone - 核心位置警报

Question

我在 O'Reilly 教程中看到了以下警报：

1. http://answers.oreilly.com/index.php?app=core&module=attach§ion=attach&attach_rel_module=post&attach_id=125
2. http://answers.oreilly.com/uploads/monthly_10_2009/post-48-125435525931_thumb.jpg

我不明白如何触发这些警报。请问你能通知我吗？使用ios6的应用

Answer 1

这是访问您当前位置时的警报，当您使用CLLocationManager访问用户当前位置时，它会自动询问

-(void)getLocation
{
    locationManager = [[CLLocationManager alloc] init];
    locationManager.delegate = self;
    locationManager.distanceFilter = kCLLocationAccuracyHundredMeters;
    locationManager.desiredAccuracy = kCLLocationAccuracyBest;

    NSLog(@"eee%f",locationManager.location.coordinate.latitude);
    // Start updating location changes.
    [locationManager startUpdatingLocation];
}


- (void)startUpdatingCurrentLocation
{
    //NSLog(@"STARTUPDATELOCATION");
    // if location services are restricted do nothing
    if ([CLLocationManager authorizationStatus] == kCLAuthorizationStatusDenied ||
        [CLLocationManager authorizationStatus] == kCLAuthorizationStatusRestricted )
    {
        return;
    }

    // if locationManager does not currently exist, create it
    if (!locationManager)
    {
        locationManager = [[CLLocationManager alloc] init];
        [locationManager setDelegate:self];
        locationManager.distanceFilter = 10.0f; // we don't need to be any more accurate than 10m


    }

    [locationManager startUpdatingLocation];

    // [self showCurrentLocationSpinner:YES];
}

只需阅读CLLocationManager 类参考了解更多信息

Answer 2

好吧，它非常简单。它被称为一个UIAlertView并且非常常见的用于提供通知。它们应该用于通知用户一些事情，而不是太多的交互。

编码明智，这里是一些基本的设置文本：

UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"Alert" message:@"Alert Body" delegate:self cancelButtonTitle:@"Dismiss" otherButtonTitles:nil, nil];

要显示警报：

[alert show];

如果您想要其他按钮标题，则需要将 .h 文件中的 to 设置delegate为self并符合UIAlertViewDelegate. 这是对委托的引用，您基本上想要实现该clickedButtonAtIndex:方法并使用索引来找出用户按下了哪个按钮并执行操作。

不要滥用警报视图。