Mvvmintroduction 130725124207-phpapp01

Mvvmintroduction 130725124207-phpapp01

• 1.
  Software Architecture Pattern M-V-VM (Model-View-ViewModel) Friday,July 26, 2013
• 2.
  View ViewModel Commands Data Binding Model
• 4.
  Model public class Person { publicPerson() { } public string FirstName { get; set; } public string LastName { get; set; } public string Age { get; set; } }
• 5.
  ViewModel public class MainViewModel: INotifyPropertyChanged { public event PropertyChangedEventHandler PropertyChanged; private void NotifyPropertyChanged(String propertyName) { PropertyChangedEventHandler handler = PropertyChanged; if (null != handler) { handler(this, new PropertyChangedEventArgs(propertyName)); } } }
• 6.
  ViewModel private Person _selectedPerson; publicPerson SelectedPerson { get { return _selectedPerson; } set { if (_selectedPerson != value) { _selectedPerson = value; NotifyPropertyChanged("SelectedPerson"); } } }
• 7.
  View <TextBox Text="{Binding FirstName,Mode=TwoWay}" />
• 8.
  View <ListView ItemsSource="{Binding ListOfPerson}" SelectedItem="{Binding SelectedPerson,Mode=TwoWay}" />
• 9.
  View ViewModel Commands Data Binding Model
• 10.
  • The Modeproperty determines how changes are synchronized between the target control and data source – OneTime – Control property is set once to the data value and any subsequent changes are ignored – OneWay – Changes in the data object are synchronized to the control property, but changes in the control are not synchronized back to the data object – TwoWay – Changes in the data object are synchronized to the control property and vice- versa <TextBlock x:Name="FirstName" Text="{Binding FirstName, Mode=OneWay}"/>
• 11.
  • ViewModels implementINotifyPropertyChanged public class ProfileViewModel : INotifyPropertyChanged { private Person _person; public Person Person { get { return _person; } set { if (value != _person) { _person = value; NotifyPropertyChanged("Person"); } } } public event PropertyChangedEventHandler PropertyChanged; private void NotifyPropertyChanged(String propertyName) { if (null != PropertyChanged) PropertyChanged(this, new PropertyChangedEventArgs(propertyName)); } }
• 12.
  <Button Command="{Binding EditCommand}" CommandParameter="{BindingSelectedPerson}" Content="Edit" HorizontalAlignment="Center" VerticalAlignment="Center"/> class EditPersonCommand : ICommand { ViewModel _viewModel; public EditPersonCommand(ViewModel viewModel) { _viewModel = viewModel; } public event EventHandler CanExecuteChanged; public bool CanExecute(object parameter) { return true; } public void Execute(object person) { _viewModel.EditPerson(person as Person); } }
• 13.
  • Reuse Modeland View-Model code • Test the ViewModel with unit tests • Maintainability • Can show design-time data in Expression Blend and the Visual Studio designer
• 14.
  http://caliburnmicro.codeplex.com/http://mvvmlight.codeplex.com/ Rob EisenbergLaurent Bugnion
• 15.
  http://msdn.microsoft.com/en-us/library/gg405484%28v=pandp.40%29.aspx http://msdn.microsoft.com/en-us/magazine/jj651572.aspx
• 16.
  Software Architecture Design M-V-VM (Model-View-ViewModel) 18/07/2013