Redirection of alert box button

I would like to know if we can actual开发者_运维问答ly redirect the alert box to a specific view. Meaning that when they clicked on "View" which is on the notification alert, it will redirect them to a particular view, just like the text message notification pop up. Is there any idea on how this works?

From your question, you could mean two types of alert dialogs:

1. The generic "alert box" you mention, or UIAlertView
2. A UILocalNotification alert dialog, shown when the application is in the background ("just like the text message notification pop up")

I will address them in order.

First, how to handle a UIAlertView "View" button click.

Implement the alertView:didDismissWithButtonIndex: method of the UIAlertViewDelegate protocol in your controller class, and when you init the UIAlertView set its delegate to self. Then when the user clicks a button marked e.g. "View", do this:

- (void)alertView:(UIAlertView *)alertView didDismissWithButtonIndex:(NSInteger)buttonIndex
{
    if([[alertView buttonTitleAtIndex:buttonIndex] isEqualToString:@"View"])
    {
        // take the user to a specific view
    } else { // handle other cases if you have any
    
    }
}

Secondly, how to handle a UILocalNotification which triggers an application launch.

Apple docs on UILocalNotification state:

If the notification is an alert and the user taps the action button (or, if the device is locked, drags open the action slider), the application is launched. In the application:didFinishLaunchingWithOptions: method the application delegate can obtain the UILocalNotification object from the passed-in options dictionary by using the UIApplicationLaunchOptionsLocalNotificationKey key. The delegate can inspect the properties of the notification and, if the notification includes custom data in its userInfo dictionary, it can access that data and process it accordingly.

On the other hand, if the local notification only badges the application icon, and the user in response launches the application, the application:didFinishLaunchingWithOptions: method is invoked, but no UILocalNotification object is included in the options dictionary.

You need to write code for handling this launch case in your app delegate class, in the application:didFinishLaunchingWithOptions: method.

IF you happen to get a UILocalNotification while the app is running, Apple docs state:

If the application is foremost and visible when the system delivers the notification, no alert is shown, no icon is badged, and no sound is played. However, the application:didReceiveLocalNotification: is called if the application delegate implements it. The UILocalNotification instance is passed into this method, and the delegate can check its properties or access any custom data from the userInfo dictionary.

EDIT: To take the user to a specific view straight away, you can manually push something onto a UINavigationController stack (if your app usually operates with navigation controllers, it makes sense to do this), or present a modal view controller. I've linked there to guides for both.