Small refactor on DataGrid.

Author: azchohfi

Microsoft.Toolkit.Uwp.UI.Controls.DataGrid/DataGrid/DataGridCellsPresenter.cs

@@ -246,11 +246,11 @@ protected override Size MeasureOverride(Size availableSize)
                     {
                         cell.Measure(new Size(column.ActualMaxWidth, measureHeight));
                         this.OwningGrid.AutoSizeColumn(column, cell.DesiredSize.Width);
-                        column.ComputeLayoutRoundedWidth(totalDisplayWidth, GetScale());
+                        column.ComputeLayoutRoundedWidth(totalDisplayWidth);
                     }
                     else if (!this.OwningGrid.UsesStarSizing)
                     {
-                        column.ComputeLayoutRoundedWidth(scrollingLeftEdge, GetScale());
+                        column.ComputeLayoutRoundedWidth(scrollingLeftEdge);
                         cell.Measure(new Size(column.LayoutRoundedWidth, measureHeight));
                     }
 
@@ -283,7 +283,7 @@ protected override Size MeasureOverride(Size availableSize)
                 foreach (DataGridColumn column in this.OwningGrid.ColumnsInternal.GetVisibleColumns())
                 {
                     DataGridCell cell = this.OwningRow.Cells[column.Index];
-                    column.ComputeLayoutRoundedWidth(leftEdge, GetScale());
+                    column.ComputeLayoutRoundedWidth(leftEdge);
                     cell.Measure(new Size(column.LayoutRoundedWidth, measureHeight));
                     if (autoSizeHeight)
                     {
@@ -302,18 +302,6 @@ protected override Size MeasureOverride(Size availableSize)
             return new Size(this.OwningGrid.ColumnsInternal.VisibleEdgedColumnsWidth, this.DesiredHeight);
         }
 
-        private double GetScale()
-        {
-            if (OwningGrid.XamlRoot != null)
-            {
-                return OwningGrid.XamlRoot.RasterizationScale;
-            }
-            else
-            {
-                return Windows.Graphics.Display.DisplayInformation.GetForCurrentView().RawPixelsPerViewPixel;
-            }
-        }
-
         internal void Recycle()
         {
             // Clear out the cached desired height so it is not reused for other rows

Microsoft.Toolkit.Uwp.UI.Controls.DataGrid/DataGrid/DataGridColumn.cs

@@ -1055,10 +1055,20 @@ internal DataGridLength CoerceWidth(DataGridLength width)
         /// rounding process, so we need to do it ourselves.  If we don't, then we'll end up with some
         /// pixel gaps and/or overlaps between columns.
         /// </summary>
-        internal void ComputeLayoutRoundedWidth(double leftEdge, double scale)
+        internal void ComputeLayoutRoundedWidth(double leftEdge)
         {
             if (this.OwningGrid != null && this.OwningGrid.UseLayoutRounding)
             {
+                double scale;
+                if (OwningGrid.XamlRoot != null)
+                {
+                    scale = OwningGrid.XamlRoot.RasterizationScale;
+                }
+                else
+                {
+                    scale = Windows.Graphics.Display.DisplayInformation.GetForCurrentView().RawPixelsPerViewPixel;
+                }
+
                 double roundedLeftEdge = Math.Floor((scale * leftEdge) + 0.5) / scale;
                 double roundedRightEdge = Math.Floor((scale * (leftEdge + this.ActualWidth)) + 0.5) / scale;
                 this.LayoutRoundedWidth = roundedRightEdge - roundedLeftEdge;

Microsoft.Toolkit.Uwp.UI.Controls.DataGrid/DataGrid/DataGridColumnHeadersPresenter.cs

@@ -338,11 +338,11 @@ protected override Size MeasureOverride(Size availableSize)
                 {
                     columnHeader.Measure(new Size(column.ActualMaxWidth, double.PositiveInfinity));
                     this.OwningGrid.AutoSizeColumn(column, columnHeader.DesiredSize.Width);
-                    column.ComputeLayoutRoundedWidth(totalDisplayWidth, GetScale());
+                    column.ComputeLayoutRoundedWidth(totalDisplayWidth);
                 }
                 else if (!this.OwningGrid.UsesStarSizing)
                 {
-                    column.ComputeLayoutRoundedWidth(totalDisplayWidth, GetScale());
+                    column.ComputeLayoutRoundedWidth(totalDisplayWidth);
                     columnHeader.Measure(new Size(column.LayoutRoundedWidth, double.PositiveInfinity));
                 }
 
@@ -367,7 +367,7 @@ protected override Size MeasureOverride(Size availableSize)
                 double leftEdge = 0;
                 foreach (var column in this.OwningGrid.ColumnsInternal.GetVisibleColumns())
                 {
-                    column.ComputeLayoutRoundedWidth(leftEdge, GetScale());
+                    column.ComputeLayoutRoundedWidth(leftEdge);
                     column.HeaderCell.Measure(new Size(column.LayoutRoundedWidth, double.PositiveInfinity));
                     if (autoSizeHeight)
                     {
@@ -407,18 +407,6 @@ protected override Size MeasureOverride(Size availableSize)
             return new Size(this.OwningGrid.ColumnsInternal.VisibleEdgedColumnsWidth, height);
         }
 
-        private double GetScale()
-        {
-            if (OwningGrid.XamlRoot != null)
-            {
-                return OwningGrid.XamlRoot.RasterizationScale;
-            }
-            else
-            {
-                return Windows.Graphics.Display.DisplayInformation.GetForCurrentView().RawPixelsPerViewPixel;
-            }
-        }
-
         /// <summary>
         /// Creates AutomationPeer (<see cref="UIElement.OnCreateAutomationPeer"/>)
         /// </summary>