Thanks to Custom URL Schemes, iOS Apps can register themselves and be “woken up” by another app (such as yours). Many can even accept parameters if you do.
Opening another app happens via the UIApplication class, and an NSURL as parameter.
Here’s how we open the Facebook App and direct it to open my Pinkstone Pictures page in it:
- (IBAction)openFacebook:(id)sender {
// open the Facebook App
if (![[UIApplication sharedApplication] openURL:[NSURL URLWithString:@"fb://profile/429759140452016"]]) {
// opening the app didn't work - let's open Safari
if (![[UIApplication sharedApplication] openURL:[NSURL URLWithString:@"https://www.facebook.com/pinkstonepictures"]]) {
// nothing works - perhaps we're not onlye
NSLog(@"Note to self: find a different hobby");
}
}
}
If the app is not installed nothing happens – which may mean that the app is not installed. As a fallback we’re opening the same page with Safari. If that also doesn’t work, a log message is displayed.
Note that to pass your page into the Facebook App you need your Page or Profile ID. There are several ways to find those:
- http://findmyfacebookid.com
- http://stackideas.com/docs/easyblog/how-tos/how-to-get-my-facebook-page-id
To find out which other apps you can opened and to figure out which scheme they follow:
To register a Custom URL Scheme in your own app: