Android: What's the difference between Activity.runOnUiThread and View.post?

Question

What\'s the difference between Activity.runOnUiThread and View.post, could someone, please, explain?

Answer 1

Either are acceptable for most situations and for the most part they are interchangeable, but they are subtly different. The biggest difference of course is that one is available from an Activity and the other from a View. There's a lot of overlap between those, but sometimes in an Activity you will not have access to a View, and sometimes in a View you will not have access to an Activity.

One of the edge cases I've encountered with View.post I mentioned in an answer to another SO question on View.post: View.post only works from another thread when the View is attached to a window. This is rarely a problem, but can occasionally cause the Runnable to never execute, especially if you call View.post in the onCreate method of your Activity. An alternative is to use Handler.post which is what Activity.runOnUiThread and View.post use under the covers anyway.

(edited for accuracy, added "from another thread")