LT-22691: Answer the Insert leaf of the Lexicon detail menus natively

Src/Common/Controls/DetailControls/Slice.cs

@@ -1935,12 +1935,7 @@ private bool InsertObjectIfPossible(int newObjectClassId, int ownerClassId, stri
 				|| slice.Object.Equals(ContainingDataTree.Root)) // Other cases.
 			{
 				// The slice's object has an acceptable type provided it implements the required field.
-				// See if the current slice's object has the field named.
-				int flid = slice.GetFlid(fieldName);
-				var mdc = Cache.MetaDataCacheAccessor as IFwMetaDataCacheManaged;
-				int flidT = ContainingDataTree.GetFlidIfPossible(ownerClassId, fieldName, mdc);
-				if (flidT != 0 && flid != flidT)
-					flid = flidT;
+				int flid = DetailObjectInsertion.ResolveFlid(slice.Object, fieldName, ownerClassId);
 				if (flid == 0)
 					return false;
 				// Found a suitable slice. Do the insertion.
@@ -2027,65 +2022,25 @@ int InsertObject(int flid, int newObjectClassId, out ICmObject newObject)
 
 			newObject = null;
 
-			bool fAbstract = m_cache.DomainDataByFlid.MetaDataCache.GetAbstract(newObjectClassId);
-			if (fAbstract)
-			{
-				// We've been handed an abstract class to insert.  Try to determine the desired
-				// concrete from the context.
-				if (newObjectClassId == MoFormTags.kClassId && Object is ILexEntry)
-				{
-					var entry = (Object as ILexEntry);
-					newObjectClassId = entry.GetDefaultClassForNewAllomorph();
-				}
-				else
-				{
-					return -1;
-				}
-			}
+			newObjectClassId = DetailObjectInsertion.ConcreteClass(Object, newObjectClassId);
+			if (newObjectClassId == 0)
+				return -1;
 			// OK, we can add to property flid of the object of slice slice.
-			int insertionPosition = 0;//leave it at 0 if it does not matter
-			int hvoOwner = Object.Hvo;
-			int clidOwner = Object.ClassID;
-			int clidOfFlid = flid / 1000;
-			if (clidOwner != clidOfFlid && clidOfFlid == Object.Owner.ClassID)
+			var owner = DetailObjectInsertion.OwnerOf(Object, flid);
+			if (owner == null)
+				return -1;
+			int hvoOwner = owner.Hvo;
+			int insertionPosition;
+			try
 			{
-				hvoOwner = Object.Owner.Hvo;
+				// The current slice's key says where in the property it sits, so the new
+				// object goes after it. We might not be on the right slice to insert this
+				// item. See FWR-898.
+				insertionPosition = DetailObjectInsertion.InsertionPosition(owner, flid, CurrentSliceKeyHvos());
 			}
-			int type = GetFieldType(flid);
-			if (type == (int)CellarPropertyType.OwningSequence)
+			catch
 			{
-				try
-				{
-					// We might not be on the right slice to insert this item.  See FWR-898.
-					insertionPosition = Cache.DomainDataByFlid.get_VecSize(hvoOwner, flid);
-				}
-				catch
-				{
-					return -1;
-				}
-				if (ContainingDataTree != null && ContainingDataTree.CurrentSlice != null)
-				{
-					ISilDataAccess sda = m_cache.DomainDataByFlid;
-					int chvo = insertionPosition;
-					// See if the current slice in any way indicates a position in that property.
-					object[] key = ContainingDataTree.CurrentSlice.Key;
-					bool fGotIt = false;
-					for (int ikey = key.Length - 1; ikey >= 0 && !fGotIt; ikey--)
-					{
-						if (!(key[ikey] is int))
-							continue;
-						var hvoTarget = (int)key[ikey];
-						for (int i = 0; i < chvo; i++)
-						{
-							if (hvoTarget == sda.get_VecItem(hvoOwner, flid, i))
-							{
-								insertionPosition = i + 1; // insert after current object.
-								fGotIt = true; // break outer loop
-								break;
-							}
-						}
-					}
-				}
+				return -1;
 			}
 			var slices = new HashSet<Slice>(ContainingDataTree.Slices);
 
@@ -2095,16 +2050,6 @@ int InsertObject(int flid, int newObjectClassId, out ICmObject newObject)
 			{
 				dtContainer.SetCurrentObjectFlids(hvoOwner, flid);
 				var fieldType = (CellarPropertyType) m_cache.MetaDataCacheAccessor.GetFieldType(flid);
-				switch (fieldType)
-				{
-					case CellarPropertyType.OwningCollection:
-						insertionPosition = -1;
-						break;
-
-					case CellarPropertyType.OwningAtomic:
-						insertionPosition = -2;
-						break;
-				}
 				using (CmObjectUi uiObj = CmObjectUi.CreateNewUiObject(m_mediator, m_propertyTable, newObjectClassId, hvoOwner, flid, insertionPosition))
 				{
 					// If uiObj is null, typically CreateNewUiObject displayed a dialog and the user cancelled.
@@ -2181,6 +2126,19 @@ int InsertObject(int flid, int newObjectClassId, out ICmObject newObject)
 			return insertionPosition;
 		}
 
+		// The objects of the current slice's key, deepest first; none without a current slice.
+		private IEnumerable<int> CurrentSliceKeyHvos()
+		{
+			var key = ContainingDataTree?.CurrentSlice?.Key;
+			if (key == null)
+				yield break;
+			for (int ikey = key.Length - 1; ikey >= 0; ikey--)
+			{
+				if (key[ikey] is int hvo)
+					yield return hvo;
+			}
+		}
+
 		/// <summary>
 		/// Find a slice nested below this one whose object is hvo and expand it if it is collapsed.
 		/// </summary>

Src/Common/FwAvalonia/Detail/DataTree.cs

@@ -124,11 +124,17 @@ public void RequestRowFocusOnRebuild(IReadOnlyList<string> rowAutomationIds)
 		public void RequestObjectFocusOnRebuild(int hvo) => ObjectFocusRequested = hvo;
 
 		/// <summary>
-		/// Focuses the first shown row of the object with <paramref name="hvo"/> that can
-		/// take focus; false when none can.
+		/// Focuses the first shown editor row of the object with <paramref name="hvo"/> that
+		/// can take focus, else its first header row that can; false when none can.
 		/// </summary>
 		internal bool FocusFirstRowOf(int hvo)
-			=> hvo != 0 && FocusFirstRow(Model.Fields.Where(f => f.ObjectHvo == hvo).Select(f => f.RowAutomationId));
+		{
+			if (hvo == 0)
+				return false;
+			var rows = Model.Fields.Where(f => f.ObjectHvo == hvo).ToList();
+			return FocusFirstRow(rows.Where(f => f.Kind != DetailFieldKind.Header).Select(f => f.RowAutomationId))
+				|| FocusFirstRow(rows.Where(f => f.Kind == DetailFieldKind.Header).Select(f => f.RowAutomationId));
+		}
 
 		/// <summary>
 		/// Focuses the first row of <paramref name="rowAutomationIds"/> that is shown and

Src/Common/FwAvalonia/Detail/DetailFocusMemory.cs

@@ -226,11 +226,12 @@ public static bool TryRestoreScroll(Control root, Memento memento)
 		/// <summary>
 		/// Restores the memento once the incoming view has laid out: the scroll offset first (an
 		/// offset set before layout is clamped to zero by the still-empty extent), then the
-		/// vector row's current item, then focus -- the remembered editor, else that current
-		/// item when the memento asks for it (a move or removal made from the row keeps the
-		/// keyboard in the row), else the first surviving row the outgoing view asked for (a
-		/// gesture removed the focused row), else the first row of the object it asked for (a
-		/// gesture replaced the row's object). Safe to call before the view is attached.
+		/// vector row's current item, then focus -- the object the outgoing view asked for (a
+		/// gesture added or replaced one) first of all; else the remembered editor; else that
+		/// current item when the memento asks for it (a move or removal made from the row keeps
+		/// the keyboard in the row); else the first surviving row the outgoing view asked for
+		/// (a gesture removed the focused row), which comes before the remembered editor only
+		/// when that is a row's menu button. Safe to call before the view is attached.
 		/// </summary>
 		public static void RestoreAfterLayout(Control root, Memento memento)
 		{
@@ -250,14 +251,17 @@ public static void RestoreAfterLayout(Control root, Memento memento)
 				if (needsScroll)
 					TryRestoreScroll(root, memento);
 				var vector = RestoreVectorSelection(root, memento);
-				if (!TryRestoreFocus(root, memento))
+				// The object a gesture added or replaced takes the keyboard outright. A row
+				// request yields to a surviving editor, unless the gesture was made from a
+				// row's menu button, which left focus on that button.
+				var focused = (memento.ObjectHvo != 0 || RemembersAMenuButton(memento))
+					&& RestoreRequestedFocus(root, memento);
+				if (!focused && !TryRestoreFocus(root, memento))
 				{
 					if (vector != null && WantsVectorFocus(memento))
 						vector.FocusItemAt(vector.SelectedItemIndex);
-					else if (memento.RowAutomationIds != null)
-						(root as DataTree)?.FocusFirstRow(memento.RowAutomationIds);
-					else if (memento.ObjectHvo != 0)
-						(root as DataTree)?.FocusFirstRowOf(memento.ObjectHvo);
+					else
+						RestoreRequestedFocus(root, memento);
 				}
 				// A bring-into-view request queued by a focus change is applied by the next
 				// arrange; the remembered offset is re-asserted after it.
@@ -270,6 +274,23 @@ public static void RestoreAfterLayout(Control root, Memento memento)
 			root.LayoutUpdated += onLayout;
 		}
 
+		// Whether the remembered control is a row's field-options button or hotlinks link
+		// rather than an editor.
+		private static bool RemembersAMenuButton(Memento memento)
+			=> memento.AutomationId != null
+				&& (memento.AutomationId.EndsWith(".FieldMenu", StringComparison.Ordinal)
+					|| memento.AutomationId.EndsWith(".Hotlinks", StringComparison.Ordinal));
+
+		// Focuses what the outgoing view asked for: the first surviving row of those named,
+		// else the first row of the object named; false when it asked for nothing or none can.
+		private static bool RestoreRequestedFocus(Control root, Memento memento)
+		{
+			var tree = root as DataTree;
+			if (memento.RowAutomationIds != null)
+				return tree?.FocusFirstRow(memento.RowAutomationIds) == true;
+			return memento.ObjectHvo != 0 && tree?.FocusFirstRowOf(memento.ObjectHvo) == true;
+		}
+
 		/// <summary>
 		/// Focuses the control with the memento's automation id inside <paramref name="root"/>
 		/// (which must already be attached to a TopLevel). Returns false when no match exists --

Src/Common/FwAvalonia/FwAvaloniaTests/DetailFocusMemoryTests.cs

@@ -2,6 +2,7 @@
 // This software is licensed under the LGPL, version 2.1 or later
 // (http://www.gnu.org/licenses/lgpl-2.1.html)
 
+using System;
 using System.Collections.Generic;
 using System.Linq;
 using Avalonia.Automation;
@@ -134,19 +135,97 @@ public void RequestedObjectFocus_FocusesTheFirstRowShowingTheObject()
 				"the new form's editor takes focus");
 		}
 
+		// A gesture made from a header's hotlinks link added an object: the link survives the
+		// re-show and is remembered, but the object asked for takes focus over it.
+		[AvaloniaTest]
+		public void RequestedObjectFocus_WinsOverTheRememberedHotlinksLink()
+		{
+			var first = NewViewOfForm(8, withHotlinks: true);
+			var window = new Window { Content = first, Width = 420, Height = 200 };
+			window.Show();
+			Dispatcher.UIThread.RunJobs();
+			var link = first.GetVisualDescendants().OfType<Button>()
+				.Single(b => AutomationProperties.GetAutomationId(b) == "LexEntry/identity/senses.Hotlinks");
+			link.Focus();
+			Dispatcher.UIThread.RunJobs();
+
+			first.RequestObjectFocusOnRebuild(9);
+			var memento = DetailFocusMemory.Capture(first);
+			Assert.That(memento.AutomationId, Is.EqualTo("LexEntry/identity/senses.Hotlinks"), "precondition: the link had focus");
+
+			var second = NewViewOfForm(9, withHotlinks: true);
+			DetailFocusMemory.RestoreAfterLayout(second, memento);
+			window.Content = second;
+			Dispatcher.UIThread.RunJobs();
+
+			Assert.That(FindEditor(second, "LexEntry/identity/#0@9.vern").IsFocused, Is.True,
+				"the new object's editor takes focus, not the surviving link");
+		}
+
+		// An insert made from another row's menu leaves that row's editor focused and alive;
+		// the new object still takes the keyboard, as a row request would not.
+		[AvaloniaTest]
+		public void RequestedObjectFocus_WinsOverASurvivingEditor()
+		{
+			var first = NewViewOfForm(8);
+			var window = new Window { Content = first, Width = 420, Height = 200 };
+			window.Show();
+			Dispatcher.UIThread.RunJobs();
+			FindEditor(first, "LexEntry/identity/#1@3.vern").Focus();
+			Dispatcher.UIThread.RunJobs();
+			first.RequestObjectFocusOnRebuild(8);
+			var memento = DetailFocusMemory.Capture(first);
+			Assert.That(memento.AutomationId, Is.EqualTo("LexEntry/identity/#1@3.vern"), "precondition: Gloss had focus");
+
+			var second = NewViewOfForm(8);
+			DetailFocusMemory.RestoreAfterLayout(second, memento);
+			window.Content = second;
+			Dispatcher.UIThread.RunJobs();
+
+			Assert.That(FindEditor(second, "LexEntry/identity/#0@8.vern").IsFocused, Is.True,
+				"the object asked for, not the surviving Gloss editor");
+		}
+
+		// The object asked for has a header row before its editor rows: its first editor takes
+		// focus, so typing can start at once; the header only when no editor can.
+		[AvaloniaTest]
+		public void RequestedObjectFocus_PrefersTheObjectsFirstEditor_OverItsHeader()
+		{
+			var first = NewViewOfForm(8, withHotlinks: true);
+			var window = new Window { Content = first, Width = 420, Height = 200 };
+			window.Show();
+			Dispatcher.UIThread.RunJobs();
+			first.RequestObjectFocusOnRebuild(3);
+			var memento = DetailFocusMemory.Capture(first);
+
+			var second = NewViewOfForm(8, withHotlinks: true);
+			DetailFocusMemory.RestoreAfterLayout(second, memento);
+			window.Content = second;
+			Dispatcher.UIThread.RunJobs();
+
+			Assert.That(FindEditor(second, "LexEntry/identity/#1@3.vern").IsFocused, Is.True,
+				"the Gloss editor of object 3, not its Senses header");
+		}
+
 		// A view whose Lexeme Form row shows the form with the given hvo, its row ids derived
-		// from the stable ids as the composer derives them.
-		private static DataTree NewViewOfForm(int formHvo)
+		// from the stable ids as the composer derives them; with hotlinks, a Senses header
+		// row with a hotlinks link comes first.
+		private static DataTree NewViewOfForm(int formHvo, bool withHotlinks = false)
 		{
 			var values = new List<DetailWsValue> { new DetailWsValue("vern", "casa") };
-			var fields = new List<DetailField>
+			var fields = new List<DetailField>();
+			if (withHotlinks)
 			{
-				new DetailField("LexEntry/identity/#0@" + formHvo, "Lexeme Form", "Form", "vernacular", DetailFieldKind.Text,
-					EditorClassification.Known, null, null, HostRouting.Product, values, null, null, objectHvo: formHvo),
-				new DetailField("LexEntry/identity/#1@3", "Gloss", "Gloss", "analysis", DetailFieldKind.Text,
-					EditorClassification.Known, null, null, HostRouting.Product, values, null, null, objectHvo: 3)
-			};
-			return new DataTree(new DetailModel("LexEntry", "identity", fields, new List<ViewDiagnostic>()));
+				fields.Add(new DetailField("LexEntry/identity/senses", "Senses", "Senses", null, DetailFieldKind.Header,
+					EditorClassification.GroupingNone, null, null, HostRouting.Product, null, null, null,
+					isEditable: false, isCollapsible: true, hotlinksId: "mnuDataTree-Sense-Hotlinks", objectHvo: 3));
+			}
+			fields.Add(new DetailField("LexEntry/identity/#0@" + formHvo, "Lexeme Form", "Form", "vernacular", DetailFieldKind.Text,
+				EditorClassification.Known, null, null, HostRouting.Product, values, null, null, objectHvo: formHvo));
+			fields.Add(new DetailField("LexEntry/identity/#1@3", "Gloss", "Gloss", "analysis", DetailFieldKind.Text,
+				EditorClassification.Known, null, null, HostRouting.Product, values, null, null, objectHvo: 3));
+			return new DataTree(new DetailModel("LexEntry", "identity", fields, new List<ViewDiagnostic>()),
+				menuRequested: withHotlinks ? request => { } : (Action<DetailMenuRequest>)null);
 		}
 
 		private static DataTree NewLongView()