public static void CreateStepperButtons <TButton>(IStepperRenderer renderer, out TButton downButton, out TButton upButton)
where TButton : AButton
{
downButton = (TButton)renderer.CreateButton();
downButton.Id = AppCompat.Platform.GenerateViewId();
downButton.Focusable = true;
upButton = (TButton)renderer.CreateButton();
upButton.Id = AppCompat.Platform.GenerateViewId();
upButton.Focusable = true;
downButton.Gravity = GravityFlags.Center;
downButton.Tag = renderer as Java.Lang.Object;
downButton.SetOnClickListener(StepperListener.Instance);
upButton.Gravity = GravityFlags.Center;
upButton.Tag = renderer as Java.Lang.Object;
upButton.SetOnClickListener(StepperListener.Instance);
// IMPORTANT:
// Do not be decieved. These are NOT the same characters. Neither are a "minus" either.
// The Text is a visually pleasing "minus", and the description is the phonetically correct "minus".
// The little key on your keyboard is a dash/hyphen.
downButton.Text = "－";
downButton.ContentDescription = "−";
// IMPORTANT:
// Do not be decieved. These are NOT the same characters.
// The Text is a visually pleasing "plus", and the description is the phonetically correct "plus"
// (which, unlike the minus, IS found on your keyboard).
upButton.Text = "＋";
upButton.ContentDescription = "+";
downButton.NextFocusForwardId = upButton.Id;
}
public static void UpdateButtons <TButton>(IStepperRenderer renderer, TButton downButton, TButton upButton, PropertyChangedEventArgs e = null)
where TButton : AButton
{
if (!(renderer?.Element is Stepper stepper))
{
return;
}
// NOTE: a value of `null` means that we are forcing an update
if (e == null ||
e.IsOneOf(Stepper.MinimumProperty, Stepper.MaximumProperty, Stepper.ValueProperty, VisualElement.IsEnabledProperty))
{
downButton.Enabled = stepper.IsEnabled && stepper.Value > stepper.Minimum;
upButton.Enabled = stepper.IsEnabled && stepper.Value < stepper.Maximum;
}
}