VS 11 Split application program analysis

Let's take a look at how to turn a page into a startup page

In the onLanched event, put,

  Window.Current.Content = _rootFrame;

 Window.Current.Activate();

 var _rootFrame = new Frame();

 _rootFrame.Navigate(typeof(ItemsPage), sampleData.ItemGroups);

///  Window.Current.Content ， .Activate();

Then look at what's in the ItemsPage, look at the inheritance relationship

public sealed partial class ItemsPage : Application6.Common.LayoutAwarePage

[Windows.Foundation.Metadata.WebHostHidden] public class LayoutAwarePage : Page///or inherit from page, then see why they have LayoutAwarePage, this class

New LayoutAwarePage() will be called before new ItemsPage(), that is, the constructor and fields in LayoutAwarePage will be run first; because of the inheritance relationship

The DataContext that LayoutAwarePage inherits from page is public, this.DataContext = _defaultViewModel;, which adds data context to the page inherited from LayoutAwarePage

In ItemPage, call this protected override void OnNavigatedTo(NavigationEventArgs e) { this.DefaultViewModel["Items"] = e.Parameter; } to set datacontext for itemPage, because the datacontext of itempage inherits from LayoutAwarePage and is pointing to _defaultViewModel, reference, when the object that _defaultViewModel only wants to change, the datacontext for itempage will also change, so why does LayoutAwarePage have protected IObservableMap DefaultViewModel { get { return _defaultViewModel; } }? , look at its gaze

///

///Gets an implementation of set as the///page's default . This instance can be bound and surfaces///property change notifications making it suitable for use as a trivial view model.///

By default, datacontext is set for each inherited from LayoutAwarePage, this is just for trial ViewMoDEL, if you want to change it
this.DefaultViewModel["Items"] = e.Parameter;, set different strings and objects, that's it
8 ItemsPage has a CollectionViewSource, object, CollectionViewSource. SOURCE , referenced to e.Parameter by binding to this.DefaultViewModel["Items"]

Then the control in the ItemsPage can be bound to the CollectionViewSource