Update Chatter in VisualForce Page

Hello Chatter feature in Salesforce acts like notification.
You can see the latest activity of the users.

Suppose after uploading a file to server you want to display a notification in chatter then proceed like this:

1) Click on "Start Upload" Button:

2) This is actually apex command button.

3) call a method on its action

4) The action attribute fires a method of a controller class:

5) After uploading or when certain task is finished depending upon users requirement a message is displayed in Chatter like this:

  
Enjoy Salesforcing
:)