private async void confirm_Clicked(object sender, EventArgs e)
{
if (itemName.Text != string.Empty && price.Text != string.Empty && url.Text != string.Empty)
{
TextInfo textInfo = new CultureInfo("en-US", false).TextInfo;
itemName.Text = textInfo.ToTitleCase(itemName.Text);
await FirebaseHelper.AddItem(itemName.Text, Convert.ToDouble(price.Text), url.Text);
await Navigation.PopModalAsync();
}
}
