/// <summary>
/// 在此页将要在 Frame 中显示时进行调用。
/// </summary>
/// <param name="e">描述如何访问此页的事件数据。
/// 此参数通常用于配置页。</param>
protected override void OnNavigatedTo(NavigationEventArgs e)
{
if(e.NavigationMode== NavigationMode.Back)
{
_HomeViewModel = Helper.Declares.CatachHomePageData;
}
}
public HomePage()
{
_HomeViewModel = new ViewModel.HomeViewModel();
this.DataContext = _HomeViewModel;
this.InitializeComponent();
}
public Home()
{
InitializeComponent();
BindingContext = new ViewModel.HomeViewModel();
}
public Home()
{
this.InitializeComponent();
viewmodel = new ViewModel.HomeViewModel();
this.DataContext = viewmodel;
}
void LoadMenuBasedSampleApp()
{
var nav = new NavigationPage(new ContentPage
{
Title = "Xamarin.Essentials",
Content = new Label
{
Text = "Select a sample from the \"Samples\" menu...",
HorizontalTextAlignment = TextAlignment.Center,
VerticalTextAlignment = TextAlignment.Center,
},
});
LoadApplication(new App {
MainPage = nav
});
// load the menu
var mainMenu = NSApplication.SharedApplication.MainMenu;
var samplesMenu = mainMenu.ItemWithTitle("Samples");
// deselect the samples when we return to the home page
nav.Popped += (s, e) =>
{
if (nav.StackDepth == 1)
{
SelectSampleMenuItem(null);
}
};
// add the samples to the main menu
var home = new ViewModel.HomeViewModel();
var allSamples = home.FilteredItems.ToList();
for (var i = 0; i < allSamples.Count; i++)
{
var sample = allSamples[i];
var menuItem = new NSMenuItem(sample.Name, OnSampleSelected);
menuItem.Tag = i;
menuItem.ToolTip = sample.Description;
samplesMenu.Submenu.AddItem(menuItem);
}
async void OnSampleSelected(object sender, EventArgs e)
{
if (sender is NSMenuItem menuItem)
{
SelectSampleMenuItem(menuItem);
var sample = allSamples[(int)menuItem.Tag];
await nav.PushAsync((Page)Activator.CreateInstance(sample.PageType));
}
}
void SelectSampleMenuItem(NSMenuItem menuItem)
{
// deselect previous
foreach (var mi in samplesMenu.Submenu.Items)
{
mi.State = NSCellStateValue.Off;
}
// select this one
if (menuItem != null)
{
menuItem.State = NSCellStateValue.On;
}
}
}