IOS上的OnAppearing方法

正如您所看到的,iOS中的“生命周期”是不同的。一种有用的方法是使用应用程序生命周期并将其与 Page

public partial class App : Application
{
    public EventHandler OnResumeHandler;
    public EventHandler OnSleepHandler;

    public App()
    {
        InitializeComponent();
        MainPage = new MyPage();
    }

    protected override void OnSleep()
    {
        OnSleepHandler?.Invoke(null, new EventArgs());
    }

    protected override void OnResume()
    {
        OnResumeHandler?.Invoke(null, new EventArgs());
    }
}

现在在你的 ContentPage

void Handle_OnResumeHandler(object sender, EventArgs e)
{
    Console.WriteLine("OnPauseResumeWithPage");
}

protected override void OnAppearing()
{
    (App.Current as App).OnResumeHandler += Handle_OnResumeHandler;
    base.OnAppearing();
}

protected override void OnDisappearing()
{
    (App.Current as App).OnResumeHandler -= Handle_OnResumeHandler;
    base.OnDisappearing();
}