public static async Task TryExecuteAsync <T>(this IMvxAsyncCommand <T> self, T parameter)
{
if (self.CanExecute(parameter))
{
await self.ExecuteAsync(parameter);
}
}
public static async Task TryExecuteAsync(this IMvxAsyncCommand self)
{
if (self.CanExecute())
{
await self.ExecuteAsync();
}
}
public static IDisposable SubscribeSearchText <TParameter, TResult>(this MvxViewModel <TParameter, TResult> viewModel, string propertyName, IMvxAsyncCommand searchCommand, Func <bool> canExecute)
{
var propertyChanged = Observable.FromEventPattern <PropertyChangedEventHandler, PropertyChangedEventArgs>(
h => viewModel.PropertyChanged += h, h => viewModel.PropertyChanged -= h);
var autoCompleteSuggest = propertyChanged
.Where(property => property.EventArgs.PropertyName.Equals(propertyName))
.Select(property =>
property.Sender.GetType().GetProperty(propertyName).GetValue(property.Sender) as string)
.Where(_ => canExecute())
.Throttle(TimeSpan.FromMilliseconds(250))
.DistinctUntilChanged();
IObservable <Unit> GetSuggestions() =>
Observable.FromAsync(() => searchCommand.ExecuteAsync());
var results = from searchText in autoCompleteSuggest
from suggestResult in GetSuggestions()
.TakeUntil(autoCompleteSuggest)
select suggestResult;
return(results.ObserveOn(SynchronizationContext.Current).Subscribe(
unit => { },
exception => { }
));
}
public static IDisposable SubscribeOnScrollEnd(this MvxRecyclerView recyclerView, IMvxAsyncCommand loadElements, Func <bool> canExecute)
{
var propertyChanged = Observable.FromEventPattern <EventHandler <View.ScrollChangeEventArgs>, View.ScrollChangeEventArgs>(
h => recyclerView.ScrollChange += h, h => recyclerView.ScrollChange -= h);
return(propertyChanged
.Select(_ => recyclerView.GetLayoutManager() as LinearLayoutManager ??
recyclerView.GetLayoutManager() as GridLayoutManager)
.Where(lm => lm != null && canExecute() &&
(lm.StackFromEnd
? lm.FindFirstVisibleItemPosition() <= 10
: lm.FindFirstVisibleItemPosition() + lm.ChildCount >= lm.ItemCount - 10))
.Throttle(TimeSpan.FromMilliseconds(100))
.ObserveOn(Application.SynchronizationContext)
.Subscribe(
async _ => await loadElements.ExecuteAsync(),
exception =>
Mvx.Resolve <IToastSerivce>().ShowByResourceId(exception.Message)));
}
private async void HandlePolylineClick(object sender, GoogleMap.PolylineClickEventArgs poly)
{
int id = int.Parse(poly.Polyline.Id.Trim(new Char[] { 'p', 'l' }));
await _command.ExecuteAsync(id);
}
