Package edu.cnm.deepdive.interviewprep.viewmodel

Class QuestionViewModel

java.lang.Object

androidx.lifecycle.ViewModel

androidx.lifecycle.AndroidViewModel

edu.cnm.deepdive.interviewprep.viewmodel.QuestionViewModel

All Implemented Interfaces:

DefaultLifecycleObserver, LifecycleObserver

public class QuestionViewModel
extends AndroidViewModel
implements DefaultLifecycleObserver

Implements the business logic behind the application. Interacts with the QuestionRepository to perform CRUD operations on the server.

Constructor Summary

Constructors

Constructor	Description
QuestionViewModel(Application application)	Class constructor.

Method Summary

Modifier and Type	Method	Description
void	createQuestion(Question question)	creates a question and sends a question to the questionRepository for creation on the server.
void	deleteQuestion(UUID questionId)	deletes a question from the questionRepository which subsequently deletes a question from the server.
LiveData<Question>	getQuestion()	Returns the local question variable.
LiveData<List<Question>>	getQuestions()	Returns the local questions variable.
void	onStop(LifecycleOwner owner)
void	refreshQuestion(UUID questionId)	gets a question from the questionRepository which subsequently gets a question from the server.
void	refreshQuestions()	gets a list of all questions from the question repository.
void	updateQuestion(Question question)	updates a question and sends a question to the questionRepository for updating on the server.

Methods inherited from class androidx.lifecycle.AndroidViewModel

getApplication

Methods inherited from class androidx.lifecycle.ViewModel

onCleared

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface androidx.lifecycle.DefaultLifecycleObserver

onCreate, onDestroy, onPause, onResume, onStart

Constructor Detail

QuestionViewModel

public QuestionViewModel(@NonNull
                         Application application)

Class constructor. Instantiates local class variables. Additionally, gets all the questions from the server.

Parameters:

application - an application.

Method Detail

getQuestions

public LiveData<List<Question>> getQuestions()

Returns the local questions variable.

Returns:

a reactivex LiveData List object of type Question.

getQuestion

public LiveData<Question> getQuestion()

Returns the local question variable.

Returns:

a reactivex LiveData object of type Question.

refreshQuestions

public void refreshQuestions()

gets a list of all questions from the question repository. Additionally, subscribes to the result and puts the result in the local variable questions.

updateQuestion

public void updateQuestion(Question question)

updates a question and sends a question to the questionRepository for updating on the server. Additionally, subscribes to the result and puts the result in the local variable question. Then reinitializes the questions field so that it will refresh on the screen.

Parameters:

question - An updated Question object.

createQuestion

public void createQuestion(Question question)

creates a question and sends a question to the questionRepository for creation on the server. Additionally, subscribes to the result and puts the result in the local variable question. Then reinitializes the questions field so that it will refresh on the screen.

Parameters:

question - A new Question object.

refreshQuestion

public void refreshQuestion(UUID questionId)

gets a question from the questionRepository which subsequently gets a question from the server. Additionally, subscribes to the result and puts the result in the local variable question. Then reinitializes the questions field so that it will refresh on the screen.

Parameters:

questionId - A questionId in the form of a universally unique identifier.

deleteQuestion

public void deleteQuestion(UUID questionId)

deletes a question from the questionRepository which subsequently deletes a question from the server.

Parameters:

questionId - A questionId in the form of a universally unique identifier.

onStop

public void onStop(@NonNull
                   LifecycleOwner owner)

Specified by:

onStop in interface DefaultLifecycleObserver