How to handle page close event?

Hi,

What is the proper way to handle page closing event? I'm closing page by executing PopAsync();
I tried following code:

    var page2 = App.getPage2();
            page2.Disappearing += page2_Disappearing;
            await this.Navi.PushAsync(page2);

the problmem is page2_Disappearing executes also when picker goes fullscreen.