答案 0 :(得分:2)
您可以使用ScrollView和StackLayout创建自己的水平列表。
这样的事情:
public class HorizontalList : Grid
{
private ICommand innerSelectedCommand;
private ScrollView scrollview;
private StackLayout mainPanel;
public event EventHandler SelectedItemChanged;
public static readonly BindableProperty SelectedCommandProperty =
BindableProperty.Create("SelectedCommand", typeof(ICommand), typeof(HorizontalList), null);
public static readonly BindableProperty ItemsSourceProperty =
BindableProperty.Create("ItemsSource", typeof(IEnumerable), typeof(HorizontalList), default(IEnumerable<object>), BindingMode.TwoWay, propertyChanged: ItemsSourceChanged);
public static readonly BindableProperty SelectedItemProperty =
BindableProperty.Create("SelectedItem", typeof(object), typeof(HorizontalList), null, BindingMode.TwoWay, propertyChanged: OnSelectedItemChanged);
public static readonly BindableProperty ItemTemplateProperty =
BindableProperty.Create("ItemTemplate", typeof(DataTemplate), typeof(HorizontalList), default(DataTemplate));
public ICommand SelectedCommand
{
get { return (ICommand)GetValue(SelectedCommandProperty); }
set { SetValue(SelectedCommandProperty, value); }
}
public IEnumerable ItemsSource
{
get { return (IEnumerable)GetValue(ItemsSourceProperty); }
set { SetValue(ItemsSourceProperty, value); }
}
public object SelectedItem
{
get { return (object)GetValue(SelectedItemProperty); }
set { SetValue(SelectedItemProperty, value); }
}
public DataTemplate ItemTemplate
{
get { return (DataTemplate)GetValue(ItemTemplateProperty); }
set { SetValue(ItemTemplateProperty, value); }
}
private static void ItemsSourceChanged(BindableObject bindable, object oldValue, object newValue)
{
var itemsLayout = (HorizontalList)bindable;
itemsLayout.SetItems();
}
public HorizontalList()
{
scrollview = new ScrollView();
mainPanel = new StackLayout
{
Orientation = StackOrientation.Horizontal;
HorizontalOptions = LayoutOptions.FillAndExpand
};
scrollview.Content = mainPanel;
scrollview.Orientation = ScrollOrientation.Horizontal
Children.Add(scrollview);
}
protected virtual void SetItems()
{
mainPanel.Children.Clear();
if (ItemsSource == null)
{
return;
}
innerSelectedCommand = new Command<View>(view =>
{
SelectedItem = view.BindingContext;
SelectedItem = null; // Allowing item second time selection
});
foreach (var item in ItemsSource)
{
mainPanel.Children.Add(GetItemView(item));
}
SelectedItem = null;
}
protected virtual View GetItemView(object item)
{
var content = ItemTemplate.CreateContent();
var view = content as View;
if (view == null)
{
return null;
}
view.BindingContext = item;
var gesture = new TapGestureRecognizer
{
Command = innerSelectedCommand,
CommandParameter = view
};
AddGesture(view, gesture);
return view;
}
private void AddGesture(View view, TapGestureRecognizer gesture)
{
view.GestureRecognizers.Add(gesture);
var layout = view as Layout<View>;
if (layout == null)
{
return;
}
foreach (var child in layout.Children)
{
AddGesture(child, gesture);
}
}
private static void OnSelectedItemChanged(BindableObject bindable, object oldValue, object newValue)
{
var itemsView = (HorizontalList)bindable;
if (newValue == oldValue && newValue != null)
{
return;
}
itemsView.SelectedItemChanged?.Invoke(itemsView, EventArgs.Empty);
if (itemsView.SelectedCommand?.CanExecute(newValue) ?? false)
{
itemsView.SelectedCommand?.Execute(newValue);
}
}
}
Here就是类似方法的例子。
答案 1 :(得分:0)