Text Box Validation for UITextView in Xamarin

gistfile1.cs

// sample text box
var descriptionField = new UITextView (new RectangleF (0, 230, UIScreen.MainScreen.Bounds.Width, 100)){
	BackgroundColor = UIColor.White,
	Text = " Description:",
	TextColor = ViewHelpers.DarkGray,
	Font = UIFont.FromName("Helvetica", 18f)
};
// validation
descriptionField.ShouldEndEditing = t => {
	if (string.IsNullOrEmpty (descriptionField.Text)) {
		descriptionField.Layer.BorderColor = ViewHelpers.DarkBlue.CGColor;
		descriptionField.Layer.BorderWidth = 2;
		descriptionField.Text = " Please fill in a Description:";
	} else if (descriptionField.Text.Length > 0) {
		descriptionField.Layer.BorderWidth = 0;
	}
	return true;
};