diff --git a/src/Avalonia.Controls/Repeater/IElementFactory.cs b/src/Avalonia.Controls/Repeater/IElementFactory.cs new file mode 100644 index 0000000000..6a899a6f26 --- /dev/null +++ b/src/Avalonia.Controls/Repeater/IElementFactory.cs @@ -0,0 +1,66 @@ +using Avalonia.Controls.Templates; + +namespace Avalonia.Controls +{ + /// + /// Represents the optional arguments to use when calling an implementation of the + /// 's method. + /// + public class ElementFactoryGetArgs + { + /// + /// Gets or sets the data item for which an appropriate element tree should be realized + /// when calling . + /// + public object Data { get; set; } + + /// + /// Gets or sets the that is expected to be the parent of the + /// realized element from . + /// + public IControl Parent { get; set; } + + /// + /// Gets or sets the index of the item that should be realized. + /// + public int Index { get; set; } + } + + /// + /// Represents the optional arguments to use when calling an implementation of the + /// 's method. + /// + public class ElementFactoryRecycleArgs + { + /// + /// Gets or sets the to recycle when calling + /// . + /// + public IControl Element { get; set; } + + /// + /// Gets or sets the that is expected to be the parent of the + /// realized element from . + /// + public IControl Parent { get; set; } + } + + /// + /// A data template that supports creating and recyling elements for an . + /// + public interface IElementFactory : IDataTemplate + { + /// + /// Gets an . + /// + /// The element args. + public IControl GetElement(ElementFactoryGetArgs args); + + /// + /// Recycles an that was previously retrieved using + /// . + /// + /// The recycle args. + public void RecycleElement(ElementFactoryRecycleArgs args); + } +} diff --git a/src/Avalonia.Controls/Repeater/ItemTemplateWrapper.cs b/src/Avalonia.Controls/Repeater/ItemTemplateWrapper.cs index 04d859c742..4b784375a9 100644 --- a/src/Avalonia.Controls/Repeater/ItemTemplateWrapper.cs +++ b/src/Avalonia.Controls/Repeater/ItemTemplateWrapper.cs @@ -7,13 +7,27 @@ using Avalonia.Controls.Templates; namespace Avalonia.Controls { - internal class ItemTemplateWrapper + internal class ItemTemplateWrapper : IElementFactory { private readonly IDataTemplate _dataTemplate; public ItemTemplateWrapper(IDataTemplate dataTemplate) => _dataTemplate = dataTemplate; - public IControl GetElement(IControl parent, object data) + public bool SupportsRecycling => false; + public IControl Build(object param) => GetElement(null, param); + public bool Match(object data) => _dataTemplate.Match(data); + + public IControl GetElement(ElementFactoryGetArgs args) + { + return GetElement(args.Parent, args.Data); + } + + public void RecycleElement(ElementFactoryRecycleArgs args) + { + RecycleElement(args.Parent, args.Element); + } + + private IControl GetElement(IControl parent, object data) { var selectedTemplate = _dataTemplate; var recyclePool = RecyclePool.GetPoolInstance(selectedTemplate); @@ -37,7 +51,7 @@ namespace Avalonia.Controls return element; } - public void RecycleElement(IControl parent, IControl element) + private void RecycleElement(IControl parent, IControl element) { var selectedTemplate = _dataTemplate; var recyclePool = RecyclePool.GetPoolInstance(selectedTemplate); diff --git a/src/Avalonia.Controls/Repeater/ItemsRepeater.cs b/src/Avalonia.Controls/Repeater/ItemsRepeater.cs index 87f4760156..8bc356bdec 100644 --- a/src/Avalonia.Controls/Repeater/ItemsRepeater.cs +++ b/src/Avalonia.Controls/Repeater/ItemsRepeater.cs @@ -141,7 +141,7 @@ namespace Avalonia.Controls /// public ItemsSourceView ItemsSourceView { get; private set; } - internal ItemTemplateWrapper ItemTemplateShim { get; set; } + internal IElementFactory ItemTemplateShim { get; set; } internal Point LayoutOrigin { get; set; } internal object LayoutState { get; set; } internal IControl MadeAnchor => _viewportManager.MadeAnchor; @@ -664,7 +664,7 @@ namespace Avalonia.Controls } } - ItemTemplateShim = new ItemTemplateWrapper(newValue); + ItemTemplateShim = newValue as IElementFactory ?? new ItemTemplateWrapper(newValue); InvalidateMeasure(); } diff --git a/src/Avalonia.Controls/Repeater/ViewManager.cs b/src/Avalonia.Controls/Repeater/ViewManager.cs index eff51804b9..416b1e2824 100644 --- a/src/Avalonia.Controls/Repeater/ViewManager.cs +++ b/src/Avalonia.Controls/Repeater/ViewManager.cs @@ -6,11 +6,9 @@ using System; using System.Collections.Generic; using System.Collections.Specialized; -using System.Linq; using Avalonia.Controls.Templates; using Avalonia.Input; using Avalonia.Interactivity; -using Avalonia.Layout; using Avalonia.Logging; using Avalonia.VisualTree; @@ -26,6 +24,8 @@ namespace Avalonia.Controls private readonly UniqueIdElementPool _resetPool; private IControl _lastFocusedElement; private bool _isDataSourceStableResetPending; + private ElementFactoryGetArgs _elementFactoryGetArgs; + private ElementFactoryRecycleArgs _elementFactoryRecycleArgs; private int _firstRealizedElementIndexHeldByLayout = FirstRealizedElementIndexDefault; private int _lastRealizedElementIndexHeldByLayout = LastRealizedElementIndexDefault; private bool _eventsSubscribed; @@ -134,7 +134,14 @@ namespace Avalonia.Controls if (_owner.ItemTemplateShim != null) { - _owner.ItemTemplateShim.RecycleElement(_owner, element); + var context = _elementFactoryRecycleArgs ??= new ElementFactoryRecycleArgs(); + context.Element = element; + context.Parent = _owner; + + _owner.ItemTemplateShim.RecycleElement(context); + + context.Element = null; + context.Parent = null; } else { @@ -579,7 +586,7 @@ namespace Avalonia.Controls var data = _owner.ItemsSourceView.GetAt(index); var providedElementFactory = _owner.ItemTemplateShim; - ItemTemplateWrapper GetElementFactory() + IElementFactory GetElementFactory() { if (providedElementFactory == null) { @@ -602,7 +609,20 @@ namespace Avalonia.Controls } var elementFactory = GetElementFactory(); - return elementFactory.GetElement(_owner, data); + var args = _elementFactoryGetArgs ??= new ElementFactoryGetArgs(); + + try + { + args.Data = data; + args.Parent = _owner; + args.Index = index; + return elementFactory.GetElement(args); + } + finally + { + args.Data = null; + args.Parent = null; + } } var element = GetElement(); @@ -732,6 +752,7 @@ namespace Avalonia.Controls { _owner.GotFocus += OnFocusChanged; _owner.LostFocus += OnFocusChanged; + _eventsSubscribed = true; } }