Custom TUI Library WIP

2023-08-08 00:27:42 +02:00
parent 7807a82f3f
commit a77d5cc235
22 changed files with 334 additions and 282 deletions
--- a/src/Library/TerminalUI/Controls/ListView.cs
+++ b/src/Library/TerminalUI/Controls/ListView.cs
@@ -0,0 +1,85 @@
+using System.Buffers;
+using System.Collections.ObjectModel;
+using DeclarativeProperty;
+
+namespace TerminalUI.Controls;
+
+public class ListView<TDataContext, TItem> : View<TDataContext>
+{
+    private static readonly ArrayPool<ListViewItem<TItem>> ListViewItemPool = ArrayPool<ListViewItem<TItem>>.Shared;
+
+    private readonly List<IDisposable> _itemsDisposables = new();
+    private Func<IEnumerable<TItem>>? _getItems;
+    private object? _itemsSource;
+    private ListViewItem<TItem>[]? _listViewItems;
+    private int _listViewItemLength;
+
+    public object? ItemsSource
+    {
+        get => _itemsSource;
+        set
+        {
+            if (_itemsSource == value) return;
+            _itemsSource = value;
+
+            foreach (var disposable in _itemsDisposables)
+            {
+                disposable.Dispose();
+            }
+
+            _itemsDisposables.Clear();
+
+            if (_itemsSource is IDeclarativeProperty<ObservableCollection<TItem>> observableDeclarativeProperty)
+                _getItems = () => observableDeclarativeProperty.Value;
+            else if (_itemsSource is IDeclarativeProperty<ReadOnlyObservableCollection<TItem>> readOnlyObservableDeclarativeProperty)
+                _getItems = () => readOnlyObservableDeclarativeProperty.Value;
+            else if (_itemsSource is IDeclarativeProperty<IEnumerable<TItem>> enumerableDeclarativeProperty)
+                _getItems = () => enumerableDeclarativeProperty.Value;
+            else if (_itemsSource is ICollection<TItem> collection)
+                _getItems = () => collection;
+            else if (_itemsSource is TItem[] array)
+                _getItems = () => array;
+            else if (_itemsSource is IEnumerable<TItem> enumerable)
+                _getItems = () => enumerable.ToArray();
+
+            if (_listViewItems is not null)
+            {
+                ListViewItemPool.Return(_listViewItems);
+                _listViewItems = null;
+            }
+
+            OnPropertyChanged();
+        }
+    }
+
+    public override void Render()
+    {
+        if (_getItems is null) return;
+        var items = _getItems().ToList();
+
+        Span<ListViewItem<TItem>> listViewItems = null;
+
+        if (_listViewItems is null || _listViewItems.Length != items.Count)
+        {
+            var newListViewItems = ListViewItemPool.Rent(items.Count);
+            for (var i = 0; i < items.Count; i++)
+            {
+                var dataContext = items[i];
+                newListViewItems[i] = CreateChild<ListViewItem<TItem>, TItem>(_ => dataContext);
+            }
+
+            _listViewItems = newListViewItems;
+            _listViewItemLength = items.Count;
+            listViewItems = newListViewItems[..items.Count];
+        }
+        else
+        {
+            listViewItems = _listViewItems[.._listViewItemLength];
+        }
+
+        foreach (var item in listViewItems)
+        {
+            item.Render();
+        }
+    }
+}