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Java Build a JavaFX Application It's About Time Wire It Up

Alan Kennedy
Alan Kennedy
Courses Plus Student 616 Points

Why was it used?

public void handlePlay(ActionEvent actionEvent) { if(mCurrentAttempt==null){ handleRestart(actionEvent); } else { playTimer(); } }

Jenna Dercole
Jenna Dercole
30,224 Points

We need some context before we can give you a proper answer. What lesson does this pertain to? Why is what used?

1 Answer

Matthew Timmons
Matthew Timmons
33,804 Points

When the application is first started, mCurrentAttempt is null. It is only set in the method, "prepareAttempt," which is only called in the method, "handleRestart." This logic says, "Check if mCurrentAttempt is null. If it is, then go ahead and call the function, 'handleRestart.' This will instantiate the variable, mCurrentAttempt. It will then start the timer. If it is not null, A.K.A. it has been instantiated at some point in this application, then just call the method, 'playTimer.'"

The flow can be represented as:

App starts -> User clicks the play button -> handlePlay sees that mCurrentAttempt is null, so it calls the same method that the restart button calls, "handleRestart" -> App calls prepareAttempt(AttemptKind.FOCUS), which sets the timer to 25 minutes and sets the styles -> app calls playTimer() which starts the timer.

Please let me know if this helps or if you have any questions. Thank you.