How do I detect, via javascript in Safari Mobile, if my iPhone application is installed?

Question

As you probably know, iPhone applications can register a custom URL scheme handler, ala "myapp:" and these can be used for links in a page viewed in Safari.

I'd like to automatically launch my application from a specific page if the visitor has the app installed. If the app's not installed, I'll just show them the current mobile-optimized view of the page.

How can I do this detection? Google searches have been fruitless. Also, to be tricky, I've tried doing something like this to no avail:

var image = new Image();
image.onerror = function(e){
  alert("bummer");
}
image.onload = function(e){
  alert('success!');
}
image.src = 'myapp://something=meaningful';

Has anyone come across a way to do application detection?

Answer 1

我在另一个Stack Overflow问题上提出的解决方案与您将获得的解决方案尽可能接近。

Answer 2

I don't think this is possible. You would need to register your app on the iPhone/Mobile Safari and then create a uri to fire your app up, just like http:, ftp: mailto:. So in your case you would have something like Am I installed Mobile Safari would need to know what app to fire up to load that URI and I just don't think this functionality is built into the iPhone. I know there is no way javascript can query your iPhone to see what's installed.

I hope I am wrong as this seems like it would be a powerful feature, though on the other side I can see some security issues related to something like this.

Good luck.