Hi Peter,
Can you please list the source of the quote? It is important so folks know what the source material is (see:
QuoteYourSources).
The
action is what you want to do (open a web page, send a text message, list contacts, etc...) and the
action handler is who does the action (what browser displays the web page, what application sends the text message, how the contacts are listed on screen). 'Loosely coupled' means the code intending to do the action doesn't need to know how action will be performed, they just know what action they want. The OS is free to substitute whatever it wants to execute that action, as long as the action is handled. For one user 'launch this web page' may be executed by Chrome, and for another user launch this web page' might be executed by Opera. This loose coupling makes the OS very flexible and is why an Android user can substitute a third party browser, or keyboard, or whatever, and we developers don't have to be aware of that substitution in order to deliver the user a consistent experience.