將緯度和經度坐標發送到應用程序委托中的didFinishLaunchingWithOptions

Question

我有一個此函數可以在我的應用程序委托中獲取較長時間，並且工作正常：

- (void)newPhysicalLocation:(CLLocation *)location {

    // Store for later use
    self.lastKnownLocation = location;

    // Remove spinner from view
    for (UIView *v in [self.viewController.view subviews])
    {
        if ([v class] == [UIActivityIndicatorView class])
        {
            [v removeFromSuperview];
            break;
        }
    }

    // Alert user
    UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"Location Found" message:[NSString stringWithFormat:@"Found physical location.  %f %f", self.lastKnownLocation.coordinate.latitude, self.lastKnownLocation.coordinate.longitude] delegate:self cancelButtonTitle:@"OK" otherButtonTitles: nil];
    [alert show];
    [alert release];  

    currentLatitude = (self.lastKnownLocation.coordinate.latitude);
    NSLog(@"current latitude: %f",self.lastKnownLocation.coordinate.latitude);


    currentLongitude = (self.lastKnownLocation.coordinate.longitude);
    NSLog(@"current longitude: %f",currentLongitude);
}

但是，我正在嘗試在didFinishLaunchingWithOptions部分中將currentLatitude和currentLongitude值發送到應用程序委托的頂部。 我正在嘗試執行此操作，以便可以將這些值傳遞到我在其中設置的另一個viewController中：

MyAppDelegate *appDelegate = (MyAppDelegate *)[[UIApplication sharedApplication] delegate];

我可以將currentLatitude和currentLongitude值發送到didFinishLaunchingWithOptions部分嗎？

Answer 1

為什么不在第二個viewController中創建currentLatitude和currentLongitude ？

您可以使用

- (void)newPhysicalLocation:(CLLocation *)location {
    // your code here

    SecondViewController *viewController = [[SecondViewController alloc] init];
    [viewController setLatitude: currentLatitude andLongitude: currentLongitude];
}

要不就

[viewController setCurrentLatitude: currentLatitude];
[viewController setCurrentLongitude: currentLongitude];

Answer 2

根據您對問題的了解，您希望將這些坐標值傳遞給另一個視圖控制器。 如果是這樣，您可以將currentLatitude和currentLongitude用作應用程序委托的類變量。 然后，當您在applicationDidFinishLaunchingWithOptions:調用此函數時applicationDidFinishLaunchingWithOptions:您可以將值分配給這些類變量。 然后，您可以通過應用程序委托的實例在任何地方訪問這些變量。

注意：如果要在類外訪問變量，則必須合成變量。

希望這可以幫助