postDelayed
Causes the Runnable r to be added to the message queue, to be run after the specified amount of time elapses. The runnable will be run on the thread to which this handler is attached. The time-base is uptimeMillis. Time spent in deep sleep will add an additional delay to execution.
Return
Returns true if the Runnable was successfully placed in to the message queue. Returns false on failure, usually because the looper processing the message queue is exiting. Note that a result of true does not mean the Runnable will be processed -- if the looper is quit before the delivery time of the message occurs then the message will be dropped.
Parameters
handler to use for posting the runnable.
The Runnable that will be executed.
An instance which can be used to cancel r via removeCallbacksAndMessages.
The delay (in milliseconds) until the Runnable will be executed.