ExtendedListView

//using Satrack.SpecialTransport.Cross.Selectors; using System; using Xamarin.Forms; namespace BeatifulPlace.App.Controls { public class ExtendedListView : ListView { private DataTemplateSelector currentItemSelector; public ExtendedListView() { this.ItemSelected += ExtendedListView_ItemSelected; } public static readonly BindableProperty ItemTemplateSelectorProperty = BindableProperty.Create("ItemTemplateSelector", typeof(DataTemplateSelector), typeof(ExtendedListView), null, propertyChanged: OnDataTemplateSelectorChanged); public DataTemplateSelector ItemTemplateSelector { get { return (DataTemplateSelector)GetValue(ItemTemplateSelectorProperty); } set { SetValue(ItemTemplateSelectorProperty, value); } } public static readonly BindableProperty IsSelectionEnabledProperty = BindableProperty.Create<ExtendedListView, bool>(o => o.IsSelectionEnabled, default(bool)); public bool IsSelectionEnabled { get { return (bool)GetValue(IsSelectionEnabledProperty); } set { SetValue(IsSelectionEnabledProperty, value); } } void ExtendedListView_ItemSelected(object sender, SelectedItemChangedEventArgs e) { var listView = (ExtendedListView)sender; if (!listView.IsSelectionEnabled) { if (e == null) return; listView.SelectedItem = null; } } private static void OnDataTemplateSelectorChanged(BindableObject bindable, object oldvalue, object newvalue) { ((ExtendedListView)bindable).OnDataTemplateSelectorChanged((DataTemplateSelector)oldvalue, (DataTemplateSelector)newvalue); } protected virtual void OnDataTemplateSelectorChanged(DataTemplateSelector oldValue, DataTemplateSelector newValue) { // check to see we don't have an ItemTemplate set if (ItemTemplate != null && newValue != null) throw new ArgumentException("Cannot set both ItemTemplate and ItemTemplateSelector", "ItemTemplateSelector"); currentItemSelector = newValue; } protected override Cell CreateDefault(object item) { if (currentItemSelector != null) { var template = currentItemSelector.SelectTemplate(item, this); if (template != null) { var templateInstance = template.CreateContent(); // see if it's a view or a cell var templateView = templateInstance as View; var templateCell = templateInstance as Cell; if (templateView == null && templateCell == null) throw new InvalidOperationException("DataTemplate must be either a Cell or a View"); if (templateView != null) // we got a view, wrap in a cell templateCell = new ViewCell { View = templateView }; return templateCell; } } return base.CreateDefault(item); } } }