watsonb8/aurora
1
1
Fork 0
Code Issues 1 Pull Requests Projects 1 Releases Wiki Activity

Viewmodels are now maintained throughout the app lifecycle

Browse Source
This commit is contained in:
watsonb8
2019-07-15 15:03:59 -04:00
parent 00b39b1d84
commit a3937e78da
9 changed files with 70 additions and 15 deletions
Download Patch File Download Diff File Expand all files Collapse all files

53
Aurora/Design/Views/MainView/MainView.xaml.cs
View File

@ -1,5 +1,6 @@
using System;
using System.Collections.ObjectModel;
using System.Collections.Generic;
using System.Linq;
using Aurora.Design.Components.NavigationMenu;
using Aurora.Design.Views.MainView;
@ -11,10 +12,14 @@ namespace Aurora.Design.Views.Main
[XamlCompilation(XamlCompilationOptions.Compile)]
public partial class MainView : MasterDetailPage
{
private Dictionary<int, BaseViewModel> _viewModels;
private BaseViewModel _lastViewModel;
public MainView()
{
InitializeComponent();
BindingContext = new MainViewModel();
_viewModels = new Dictionary<int, BaseViewModel>();
MasterPage.ListView.ItemSelected += ListView_ItemSelected;
Appearing += OnAppearing;
@ -32,6 +37,33 @@ namespace Aurora.Design.Views.Main
var view = (View)Activator.CreateInstance(item.TargetType);
//Check if we have an instantiated viewModel
BaseViewModel vm = new BaseViewModel();
if (_viewModels.ContainsKey(item.Id))
{
_viewModels.TryGetValue(item.Id, out vm);
}
else
{
if (item.TargetViewModelType.BaseType != typeof(BaseViewModel))
{
throw new InvalidOperationException("TargetViewModel field must be of type BaseViewModel");
}
//Instantiate new view model
vm = (BaseViewModel)Activator.CreateInstance(item.TargetViewModelType);
_viewModels.Add(item.Id, vm);
}
//Activate viewmodel
vm.OnActive();
//Deactivate last viewModel
_lastViewModel.OnInactive();
//Assign viewModel
_lastViewModel = vm;
view.BindingContext = vm;
ContentPresenter viewContent = (ContentPresenter)ContentPage.Content.FindByName("ViewContent");
viewContent.Content = view;
@ -47,7 +79,26 @@ namespace Aurora.Design.Views.Main
{
//Set initial view from first item in list
ObservableCollection<NavigationGroupItem> screenList = (ObservableCollection<NavigationGroupItem>)MasterPage.ListView.ItemsSource;
var view = (View)Activator.CreateInstance(screenList.FirstOrDefault().FirstOrDefault().TargetType);
//Assign viewModel
NavigationItem firstNavItem = screenList.FirstOrDefault().FirstOrDefault();
var view = (View)Activator.CreateInstance(firstNavItem.TargetType);
BaseViewModel vm = new BaseViewModel();
if (_viewModels.ContainsKey(firstNavItem.Id))
{
_viewModels.TryGetValue(firstNavItem.Id, out vm);
}
else
{
//Instantiate new view model
vm = (BaseViewModel)Activator.CreateInstance(firstNavItem.TargetViewModelType);
_viewModels.Add(firstNavItem.Id, vm);
}
view.BindingContext = vm;
_lastViewModel = vm;
vm.OnActive();
ContentPresenter viewContent = (ContentPresenter)ContentPage.Content.FindByName("ViewContent");
viewContent.Content = view;