protected override TView CreateItem(AndroidContext context, AndroidViewGroup <TView> element)
{
var instance = (TView)Activator.CreateInstance(typeof(TView), context.Context);
var dimensions = element.Attributes.GetAttributeOrDefault(View.DimensionsAttribute);
var lp = context.LayoutParamsFactory?.Invoke(dimensions ?? Dimensions.MatchMatch);
if (lp != null)
{
instance.LayoutParameters = lp;
}
return(instance);
}
/// <summary>
/// Create the UI
/// </summary>
/// <param name="context"></param>
/// <param name="initial"></param>
/// <returns></returns>
protected override IShadow <TView> Create(AndroidContext context, AndroidViewGroup <TView> initial)
{
// call down to the base to get the shadow
var shadow = (Shadow <TView>)base.Create(context, initial);
// create the connector to the android view group
var groupConnector =
new ShadowGroupConnector <Android.Views.View>(context, new AndroidViewGroupConnection(shadow));
// get the collection comparer, which the user may have overridden from the default one
var comparer = initial.Attributes.GetAttributeOrDefault(Group.ComparerAttribute) ?? PrimitiveCollectionComparer.Default;
// create the update handler which connects the comparer with the connector
var dataUpdateHandler = new BackingStoreUpdateHandler <AndroidContext, TView, IPrimitive>(groupConnector, Group.ChildrenAttribute, comparer);
// and finally set this as the adapter to be used
this.SetChildrenAdapter(context, shadow, dataUpdateHandler);
return(shadow);
}
/// <summary>
/// Create a <see cref="AndroidViewGroup{TView}"/> instance with a specified <see cref="Android.Views.ViewGroup.LayoutParams"/> factory.
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="children"></param>
/// <param name="layoutParams"></param>
/// <param name="dimensions"></param>
/// <param name="id"></param>
/// <returns></returns>
public static AndroidViewGroup <T> ViewGroup <T>(IEnumerable <IPrimitive> children, Func <Dimensions, ViewGroup.LayoutParams> layoutParams, Dimensions dimensions = default, int?id = default) where T : Android.Views.ViewGroup
{
var control = new AndroidViewGroup <T>(layoutParams);
if (dimensions != default)
{
control.Dimensions(dimensions);
}
if (id.HasValue)
{
control.Id(id.Value);
}
if (children != null)
{
control.Attributes.SetAttribute(Group.ChildrenAttribute, children.ToArray());
}
return(control);
}
protected static AndroidContext CreateChildrenContext(AndroidContext context, IShadow <TView> shadow, AndroidViewGroup <TView> current, AndroidViewGroup <TView> next)
{
var layoutParamsFactory = (current ?? next).LayoutParamsFactory;
var layoutContext = context.With((c) => c.LayoutParamsFactory = layoutParamsFactory);
return(layoutContext);
}
/// <summary>
/// Remove this control from the UI
/// </summary>
/// <param name="context"></param>
/// <param name="shadow"></param>
/// <param name="current"></param>
/// <remarks>
/// We remove the children first, then do any 'remove' at this level
/// </remarks>
protected override void Remove(AndroidContext context, IShadow <TView> shadow, AndroidViewGroup <TView> current)
{
this.RemoveChildren(context, shadow, current);
this.ClearChildrenAdapter(context, shadow);
base.Remove(context, shadow, current);
}
/// <summary>
/// Update the UI
/// </summary>
/// <param name="context"></param>
/// <param name="shadow"></param>
/// <param name="current"></param>
/// <param name="next"></param>
/// <remarks></remarks>
/// <remarks>
/// We do the children first, then we do 'this' level
/// </remarks>
protected override void Update(AndroidContext context, IShadow <TView> shadow, AndroidViewGroup <TView> current, AndroidViewGroup <TView> next)
{
// create the context
var childrenContext = CreateChildrenContext(context, shadow, current, next);
// and update the children using the previously assigned adapter
this.UpdateChildren(childrenContext, shadow, current, next);
// and finally do this...
base.Update(context, shadow, current, next);
}