/// <summary>
/// Build the elements retrieving as required from the specified elements instance.
/// </summary>
public async void Build(Elements elements)
{
if (GetElement == null)
{
elements.Get(Key,
new Act <Element, Elements, IAction <Element> >(OnRootLoaded, null, elements, null));
}
else
{
OnRootLoaded(await GetElement.RunAsync(), elements, null);
}
}
/// <summary>
/// Asynchronously fetch the item.
/// </summary>
public async Task <T> Fetch()
{
T reference;
if (_set && _item.TryGetTarget(out reference))
{
return(reference);
}
reference = await GetItem.RunAsync();
if (reference != null)
{
if (_set)
{
_item.SetTarget(reference);
}
else
{
_set = true;
_item = new WeakReference <T>(reference);
}
}
return(reference);
}
/// <summary>
/// Get the element asynchronously.
/// </summary>
public async Task <Element> GetAsync()
{
Element result = null;
_lock.Take();
if (_processing)
{
if (_element == null)
{
_lock.Release();
if (_path == null)
{
result = await _getElement.RunAsync();
}
else
{
var parser = new ElementParser(_path).RunSync();
if (parser.Error == null)
{
result = parser.Root;
}
else
{
Log.Error("Element parser error. " + parser.Error);
}
}
if (result == null)
{
return(null);
}
if (_onBuild != null)
{
_onBuild.ArgA = result;
_onBuild.Run();
}
}
else
{
result = _element.Clone();
_lock.Release();
}
return(result);
}
// check if the link has or should be updated
if (_element == null)
{
if (_path == null)
{
result = await _getElement.RunAsync();
}
else
{
var parser = new ElementParser(_path).RunSync();
if (parser.Error == null)
{
result = parser.Root;
}
else
{
_lock.Release();
Log.Error("Element parser error. " + parser.Error);
return(null);
}
}
_element = result;
if (_onBuild != null)
{
_onBuild.ArgA = _element;
_onBuild.Run();
}
if (_cacheTime > 0)
{
_nextUpdate = Time.Milliseconds + _cacheTime;
}
else
{
_nextUpdate = long.MaxValue;
}
}
else
{
if (_nextUpdate < Time.Milliseconds)
{
if (_path == null)
{
result = await _getElement.RunAsync();
if (result == null)
{
_lock.Release();
return(null);
}
}
else
{
var parser = new ElementParser(_path).RunSync();
if (parser.Error != null)
{
_lock.Release();
Log.Error("Element parser error. " + parser.Error);
return(null);
}
result = parser.Root;
}
_element = result;
if (_onBuild != null)
{
_onBuild.ArgA = _element;
_onBuild.Run();
}
if (_cacheTime > 0)
{
_nextUpdate = Time.Milliseconds + _cacheTime;
}
else
{
_nextUpdate = long.MaxValue;
}
}
}
// iterate and run the callbacks
foreach (var callback in _callbacks)
{
callback.ArgA = _element.Clone();
ManagerUpdate.Control.AddSingle(callback);
}
_callbacks.Clear();
result = _element.Clone();
_lock.Release();
return(result);
}
