Intercepting containers for threads.

2025-10-26 23:35:09 +01:00
parent 79d5b6ed40
commit d9fc365aeb
12 changed files with 528 additions and 175 deletions
@@ -0,0 +1,116 @@
+using System.ComponentModel;
+using System.Linq;
+using Microsoft.UI.Xaml;
+using Microsoft.UI.Xaml.Controls;
+using Wino.Controls;
+using Wino.Helpers;
+using Wino.Mail.ViewModels.Data;
+
+namespace Wino.Mail.WinUI.Controls.ListView;
+
+public partial class WinoThreadMailItemViewModelListViewItem : ListViewItem
+{
+    public bool IsThreadExpanded
+    {
+        get { return (bool)GetValue(IsThreadExpandedProperty); }
+        set { SetValue(IsThreadExpandedProperty, value); }
+    }
+
+    public static readonly DependencyProperty IsThreadExpandedProperty = DependencyProperty.Register(nameof(IsThreadExpanded), typeof(bool), typeof(WinoThreadMailItemViewModelListViewItem), new PropertyMetadata(false, new PropertyChangedCallback(OnIsThreadExpandedChanged)));
+
+    public WinoThreadMailItemViewModelListViewItem()
+    {
+        RegisterPropertyChangedCallback(IsSelectedProperty, OnIsSelectedChanged);
+    }
+
+    private static void OnIsThreadExpandedChanged(DependencyObject sender, DependencyPropertyChangedEventArgs dp)
+    {
+        // 1. Reflect expansion changes to WinoExpander.
+        // 2. Automatically select first item on expansion, if none selected.
+        // 3. Unselect all items on collapse.
+
+        var control = sender as WinoThreadMailItemViewModelListViewItem;
+
+        var innerControl = control?.GetWinoListViewControl();
+        var expander = control?.GetExpander();
+
+        if (innerControl == null || control == null || expander == null) return;
+
+        // 1
+        expander.IsExpanded = control.IsThreadExpanded;
+
+        // 2
+        if (control.IsThreadExpanded && innerControl.SelectedItems.Count == 0 && innerControl.Items.Count > 0)
+        {
+            innerControl.SelectedItem = innerControl.Items[0];
+        }
+
+        // 3
+        if (!control.IsSelected) innerControl?.SelectedItems.Clear();
+    }
+
+    protected override void OnContentChanged(object oldContent, object newContent)
+    {
+        base.OnContentChanged(oldContent, newContent);
+
+        if (oldContent is ThreadMailItemViewModel oldMailItem)
+        {
+            UnregisterSelectionCallback(oldMailItem);
+        }
+
+        if (newContent is ThreadMailItemViewModel newMailItem)
+        {
+            IsSelected = newMailItem.IsSelected;
+            RegisterSelectionCallback(newMailItem);
+        }
+    }
+
+    private void OnIsSelectedChanged(DependencyObject sender, DependencyProperty dp)
+    {
+        IsThreadExpanded = IsSelected;
+    }
+
+    private void UnregisterSelectionCallback(ThreadMailItemViewModel mailItem)
+    {
+        mailItem.PropertyChanged -= MailPropChanged;
+    }
+
+    private void MailPropChanged(object? sender, PropertyChangedEventArgs e)
+    {
+        if (sender is not ThreadMailItemViewModel mailItem) return;
+
+        if (e.PropertyName == nameof(ThreadMailItemViewModel.IsThreadExpanded))
+        {
+            ApplySelectionForContainer(mailItem);
+        }
+    }
+
+    private void RegisterSelectionCallback(ThreadMailItemViewModel mailItem)
+    {
+        mailItem.PropertyChanged += MailPropChanged;
+    }
+
+    private void ApplySelectionForModel(ThreadMailItemViewModel mailItem)
+    {
+        if (mailItem.IsThreadExpanded != IsThreadExpanded)
+        {
+            mailItem.IsThreadExpanded = IsThreadExpanded;
+        }
+    }
+
+    private void ApplySelectionForContainer(ThreadMailItemViewModel mailItem)
+    {
+        if (IsThreadExpanded != mailItem.IsThreadExpanded) IsThreadExpanded = mailItem.IsThreadExpanded;
+    }
+
+    public WinoListView? GetWinoListViewControl()
+    {
+        var expander = GetExpander();
+
+        if (expander?.Content is WinoListView control) return control;
+
+        return null;
+    }
+
+    public WinoExpander? GetExpander() => WinoVisualTreeHelper.FindDescendants<WinoExpander>(this).FirstOrDefault();
+}