void OnClick(object sender, System.EventArgs e)
{
var page = new TargetPage();
// If we had instance of target page
//page.SliderValueChanged += OnSliderValueChanged;
// If we have not the instance of target page, use Messaging center
MessagingCenter.Subscribe <TargetPage, double>(this, Events.SliderValueChanged, OnSliderValueChanged);
Navigation.PushAsync(page);
//MessagingCenter.Unsubscribe<SubscriberPage>(this, Events.SliderValueChanged);
}
private void OnSliderValueChanged(TargetPage source, double newValue)
{
label.Text = newValue.ToString();
}