From 74636a696b5dfb63c5f1c5591dcb9714a5260f80 Mon Sep 17 00:00:00 2001
From: Edward Miller <symbiogenisis@outlook.com>
Date: Sun, 20 Oct 2024 19:09:03 -0500
Subject: [PATCH] add placeholder space when column has filtering disabled

---
 Maui.DataGrid/DataGridColumn.cs    |  4 ++++
 Maui.DataGrid/DataGridHeaderRow.cs | 37 +++++++++++++++++++++++-------
 2 files changed, 33 insertions(+), 8 deletions(-)

diff --git a/Maui.DataGrid/DataGridColumn.cs b/Maui.DataGrid/DataGridColumn.cs
index 241f0ed..2fbcd91 100644
--- a/Maui.DataGrid/DataGridColumn.cs
+++ b/Maui.DataGrid/DataGridColumn.cs
@@ -211,6 +211,8 @@ public DataGridColumn()
             VerticalOptions = LayoutOptions.Center,
         };
 
+        FilterTextboxContainer = new ContentView();
+
         FilterTextbox.SetBinding(Entry.TextProperty, new Binding(nameof(FilterText), BindingMode.TwoWay, source: this));
     }
 
@@ -406,6 +408,8 @@ public Style HeaderFilterStyle
 
     internal Label HeaderLabel { get; } = new();
 
+    internal ContentView FilterTextboxContainer { get; }
+
     internal View SortingIconContainer { get; }
 
     internal SortingOrder SortingOrder { get; set; }
diff --git a/Maui.DataGrid/DataGridHeaderRow.cs b/Maui.DataGrid/DataGridHeaderRow.cs
index 3d21206..7890bcb 100644
--- a/Maui.DataGrid/DataGridHeaderRow.cs
+++ b/Maui.DataGrid/DataGridHeaderRow.cs
@@ -179,11 +179,10 @@ private void OnVisibilityChanged(object? sender, EventArgs e)
 
     private DataGridCell CreateHeaderCell(DataGridColumn column)
     {
-        var filteringEnabled = DataGrid.FilteringEnabled && column.FilteringEnabled;
-
         if (column.HeaderCell != null)
         {
-            column.FilterTextbox.IsVisible = filteringEnabled;
+            SetFilterRow(column);
+
             return column.HeaderCell;
         }
 
@@ -214,15 +213,37 @@ private DataGridCell CreateHeaderCell(DataGridColumn column)
             CommandParameter = column,
         });
 
-        /* Configure the filter textbox */
+        SetFilterRow(column);
 
-        column.FilterTextbox.IsVisible = filteringEnabled;
-        cellContent.Children.Add(column.FilterTextbox);
-        cellContent.SetRow(column.FilterTextbox, 1);
-        cellContent.SetColumnSpan(column.FilterTextbox, 2);
+        cellContent.Children.Add(column.FilterTextboxContainer);
+        cellContent.SetRow(column.FilterTextboxContainer, 1);
+        cellContent.SetColumnSpan(column.FilterTextboxContainer, 2);
 
         return new DataGridCell(cellContent, DataGrid.HeaderBackground, column, false);
     }
 
+    private void SetFilterRow(DataGridColumn column)
+    {
+        if (DataGrid.FilteringEnabled && column.FilteringEnabled)
+        {
+            column.FilterTextboxContainer.Content = column.FilterTextbox;
+        }
+        else if (DataGrid.FilteringEnabled && DataGrid.Columns.Any(c => c.FilteringEnabled))
+        {
+            var height = DataGrid.Columns.First(c => c.FilteringEnabled).FilterTextbox.Height;
+
+            // Add placeholder
+            column.FilterTextboxContainer.Content = new BoxView
+            {
+                MinimumHeightRequest = height,
+                Color = Colors.Transparent,
+            };
+        }
+        else
+        {
+            column.FilterTextboxContainer.Content = null;
+        }
+    }
+
     #endregion Methods
 }