C# 如何从App.xaml.cs访问页面视图
我想从应用程序类的子类App访问在页面类的子类MyPage中定义的视图C# 如何从App.xaml.cs访问页面视图,c#,windows,C#,Windows,我想从应用程序类的子类App访问在页面类的子类MyPage中定义的视图 sealed partial class App : Application { public App() { this.InitializeComponent(); this.Suspending += OnSuspending; } protected override void OnLaunched(LaunchActivatedEventArgs e)
sealed partial class App : Application
{
public App()
{
this.InitializeComponent();
this.Suspending += OnSuspending;
}
protected override void OnLaunched(LaunchActivatedEventArgs e)
{
Frame rootFrame = Window.Current.Content as Frame;
if (rootFrame == null)
{
rootFrame = new Frame();
rootFrame.NavigationFailed += OnNavigationFailed;
if (e.PreviousExecutionState == ApplicationExecutionState.Terminated)
{
//TODO: Here I want to access a view in MyPage class
}
Window.Current.Content = rootFrame;
}
if (rootFrame.Content == null)
{
rootFrame.Navigate(typeof(MyPage), e.Arguments);
}
Window.Current.Activate();
}
...
}
找到了一条路
我们可以通过(MyPage)((Frame)Window.Current.Content.Content)获取页面实例
只需在MyPage类中创建一个公共方法,并通过以下方式从OnLaunched()方法中的App类调用它:
Frame rootFrame = (Frame)Window.Current.Content;
MyPage myPage = (MyPage)rootFrame.Content;
if (myPage != null)
{
myPage.MyMethod(...);
}
为什么要从App.cs访问它?因为我需要在OnLaunched()方法中更改TexBox视图的文本值,该值可在App类中进行重写(因为它继承了应用程序类)