From d164a99ed970eebb6b592ec362f60d33ada332d1 Mon Sep 17 00:00:00 2001
From: Loretta <jozsef.b@aycode.com>
Date: Fri, 17 Jul 2026 05:51:31 +0200
Subject: [PATCH] Fix: TagBox reloads on in-place Data refill

Improved MgGridFilterPanelTagBox<TData, TValue> to detect in-place Data collection refills and trigger DevExpress editor Reload(), ensuring tags resolve when the collection is updated without changing its reference. Updated MGGRID_PARAMETERS.md to document this behavior and clarify why Reload() is needed for in-place fills.
---
 .../Components/Grids/MgGridFilterPanelTagBox.cs            | 7 +++++++
 AyCode.Blazor.Components/docs/MGGRID/MGGRID_PARAMETERS.md  | 2 +-
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/AyCode.Blazor.Components/Components/Grids/MgGridFilterPanelTagBox.cs b/AyCode.Blazor.Components/Components/Grids/MgGridFilterPanelTagBox.cs
index aa40a00..bc8329b 100644
--- a/AyCode.Blazor.Components/Components/Grids/MgGridFilterPanelTagBox.cs
+++ b/AyCode.Blazor.Components/Components/Grids/MgGridFilterPanelTagBox.cs
@@ -59,6 +59,7 @@ public class MgGridFilterPanelTagBox<TData, TValue> : MgTagBox<TData, TValue>, I
             // fill the SAME instance later (AcObservableCollection.Replace) — the reference never changes, only
             // the count does (0 => N). Count() is O(1) for ICollection-backed lookups.
             var dataCount = Data?.Count() ?? -1;
+            var sameInstanceRefilled = ReferenceEquals(Data, _lastSyncedData) && dataCount != _lastSyncedDataCount;
             var dataChanged = !ReferenceEquals(Data, _lastSyncedData) || dataCount != _lastSyncedDataCount;
             var selectionDrifted = Values is null || !Values.SequenceEqual(criteriaValues);
 
@@ -66,6 +67,12 @@ public class MgGridFilterPanelTagBox<TData, TValue> : MgTagBox<TData, TValue>, I
             {
                 _lastSyncedData = Data;
                 _lastSyncedDataCount = dataCount;
+
+                // DevExpress snapshots the editor's item list and detects Data changes BY REFERENCE — an in-place
+                // fill is invisible to it, so the re-asserted Values could never resolve into tags (re-rendering
+                // does not help). Reload() (DxListEditorBase) forces the editor to re-read its Data source.
+                if (sameInstanceRefilled) Reload();
+
                 SetValuesCore(criteriaValues);
             }
         }
diff --git a/AyCode.Blazor.Components/docs/MGGRID/MGGRID_PARAMETERS.md b/AyCode.Blazor.Components/docs/MGGRID/MGGRID_PARAMETERS.md
index 6356207..cd78c76 100644
--- a/AyCode.Blazor.Components/docs/MGGRID/MGGRID_PARAMETERS.md
+++ b/AyCode.Blazor.Components/docs/MGGRID/MGGRID_PARAMETERS.md
@@ -80,7 +80,7 @@ A nullable FK column (`int?`) behaves the same — rows whose value is `null` ma
 
 **Persistence & visibility.** The panel's criteria is part of the grid's persisted layout (`GridPersistentLayout.FilterCriteria` — the AutoSave tier and the server-roamed UserSave tier alike; see `MGGRID_LAYOUT.md`). Components register with the grid (`IMgGridFilterPanelComponent`, weakly held; `MgGridFilterPanelTagBox` does this automatically) and the grid **reconciles** them after layout restore (incl. on another machine), user-layout load, layout reset, and panel toggle:
 
-- panel **visible** → each component re-reads its field's criteria and re-selects (a restored panel filter is visible again); the restore (JS interop) and an async lookup `Data` arrive in arbitrary order — the tag box re-asserts its selection idempotently on every parameter pass while an owned criteria is active, tracking both the `Data` **instance and its item count** (an in-place fill — `AcObservableCollection.Replace` on a pre-created empty collection — is detected too), so tags resolve as soon as both exist; consumers can additionally force a re-run via `IMgGridBase.RefreshFilterPanel()` after a late lookup load;
+- panel **visible** → each component re-reads its field's criteria and re-selects (a restored panel filter is visible again); the restore (JS interop) and an async lookup `Data` arrive in arbitrary order — the tag box re-asserts its selection idempotently on every parameter pass while an owned criteria is active, tracking both the `Data` **instance and its item count** (an in-place fill — `AcObservableCollection.Replace` on a pre-created empty collection — is detected too, and triggers the editor's `Reload()`: DevExpress snapshots its item list and detects `Data` changes by reference, so an in-place fill would otherwise never resolve into tags), so tags resolve as soon as both exist; consumers can additionally force a re-run via `IMgGridBase.RefreshFilterPanel()` after a late lookup load;
 - panel **hidden** (toolbar toggle or `ShowFilterPanel="false"`) → the components' **own** criteria are **cleared** — a panel filter never filters invisibly. Hiding the panel therefore deliberately discards the current selection (filter-row values survive, per Ownership above);
 - a per-field criteria the component does not own is left untouched — the component just shows no selection.