Fix ListView demo navigation issue after back navigation

[ddechew]

Problem

In the ListViewDemos sample (under 8.0 -> Views -> ListViewDemos), navigation using TextCell items stops working after returning from a detail page using the back arrow.

Although the BindingContext remains set, the commands on TextCells stop responding after navigating back.

Solution

In MainPage.xaml.cs, I added a workaround that forces the page to refresh its bindings when it becomes visible again:

protected override void OnAppearing() { base.OnAppearing(); BindingContext = null; BindingContext = this; }