public CreateQuestionViewModel()
{
Question = new Question();
Questions = new ObservableCollection<Question>();
_questionRepository = new QuestionRepository();
Questions = _questionRepository.GetQuestions();
Question.PropertyChanged += OnQuestion_PropertyChanged;
Questions.CollectionChanged += new System.Collections.Specialized.NotifyCollectionChangedEventHandler(Questions_CollectionChanged);
}
private void BtnUpdate_OnClick(object sender, RoutedEventArgs e)
{
var viewModel = this.DataContext as CreateQuestionViewModel;
if (viewModel == null) return;
{
var question = new Question
{
Content = TxtContent.Text,
OptionA = TxtOptionA.Text,
OptionB = TxtOptionB.Text,
OptionC = TxtOptionC.Text,
OptionD = TxtOptionD.Text,
Correct = _correct
};
viewModel.UpadteQuestionCommand.Execute(question);
ResetControls();
}
}
private void lvSelectionChanged(object sender, SelectionChangedEventArgs e)
{
var item = LvQuestions.SelectedItem;
_question = item as Question;
var viewModel = this.DataContext as CreateQuestionViewModel;
if (viewModel == null) return;
if (_question == null) return;
viewModel.CloneQuestion = _question;
TxtContent.Text = _question.Content;
TxtOptionA.Text = _question.OptionA;
TxtOptionB.Text = _question.OptionB;
TxtOptionC.Text = _question.OptionC;
TxtOptionD.Text = _question.OptionD;
CoverterCorrectToRadioButton(_question.Correct);
BtnAdd.IsEnabled = false;
BtnRemove.IsEnabled = true;
BtnUpdate.IsEnabled = true;
}
//AddQuestion
public List<Question> AddQuestion(Question question)
{
if (question == null)
throw new ArgumentNullException("question");
if (!Questions.Contains(question))
{
Questions.Add(question);
}
return Questions;
}
//ContainsQuesion
public bool ContantsQuestion(Question question)
{
if (question == null)
throw new ArgumentNullException("question");
return Questions.Contains(question);
}
//UpdateQuestion
#endregion
#region Private Helpers
private List<Question> LoadQuestions()
{
Question question = null;
List<Question> questions=new List<Question>();
//using (Stream stream = GetResourceStream("./bin/Debug/Questions.xml"))
XmlDocument doc = new XmlDocument();
doc.Load("Questions.xml");
XmlElement root = doc.DocumentElement;
XmlNodeList rootQuestions = root.ChildNodes;
for (int i = 0; i < rootQuestions.Count; i++)
{
question = new Question();
XmlNode id = rootQuestions[i].SelectSingleNode("Id");
XmlNode content = rootQuestions[i].SelectSingleNode("Content");
XmlNode optionA = rootQuestions[i].SelectSingleNode("OptionA");
XmlNode optionB = rootQuestions[i].SelectSingleNode("OptionB");
XmlNode optionC = rootQuestions[i].SelectSingleNode("OptionC");
XmlNode optionD = rootQuestions[i].SelectSingleNode("OptionD");
XmlNode correct = rootQuestions[i].SelectSingleNode("Correct");
if (id != null) question.Id = Int32.Parse(id.InnerText.ToString(CultureInfo.InvariantCulture));
if (content != null) question.Content = content.InnerText.ToString(CultureInfo.InvariantCulture);
if (optionA != null) question.OptionA = optionA.InnerText.ToString(CultureInfo.InvariantCulture);
if (optionB != null) question.OptionB = optionB.InnerText.ToString(CultureInfo.InvariantCulture);
if (optionC != null) question.OptionC = optionC.InnerText.ToString(CultureInfo.InvariantCulture);
if (optionD != null) question.OptionD = optionD.InnerText.ToString(CultureInfo.InvariantCulture);
if (correct != null) question.Correct = correct.InnerText.ToString(CultureInfo.InvariantCulture);
questions.Add(question);
}
return questions;
}