AutoSize Columns in WinUI DataGrid

4 Apr 202418 minutes to read

DataGrid allows you to set the column widths based on certain logic using SfDataGrid.ColumnWidthMode or GridColumn.ColumnWidthMode property. Below is the list of predefined column sizing options available.

Type Column width
Star Divides the total width equally for columns.
Auto Calculates the width of column based on header and cell contents. So that header and cell content’s are not truncated.
AutoWithLastColumnFill Applies ColumnWidthMode.Auto width to all the columns except last column which is visible and the remaining width from total width of SfDataGrid is set to last column.
AutoLastColumnFill Applies ColumnWidthMode.Auto width to all the columns except last column which is visible and sets the maximum between last column auto spacing width and remaining width to last column.
SizeToCells Calculates the width of column based on cell contents. So that cell content’s are not truncated.
SizeToHeader Calculates the width of column based on header content. So that header content is not truncated.
None Default column width or defined width set to column.

NOTE

ColumnWidthMode will not work when the column width defined explicitly. ColumnWidthMode calculates column width based on MinWidth and MaxWidth properties.

Below code, applies ColumnWidthMode.Star to equally set width for SfDataGrid.Columns.

<syncfusion:SfDataGrid x:Name="sfDataGrid"
                        AutoGenerateColumns="True"
                        ColumnWidthMode="Star"
                        ItemsSource="{Binding OrdersDetails}"/>

Auto Size Columns in WinUI DataGrid

NOTE

The GridColumn.ColumnWidthMode takes higher priority than the SfDataGrid.ColumnWidthMode.

Fill remaining width for any column instead of last column when ColumnWidthMode is AutoLastColumnFill or AutoWithLastColumnFill 

In SfDataGrid while setting SfDataGrid.ColumnWidthMode as AutoLastColumnFill or AutoWithLastColumnFill remaining width is applied to last column. You can apply the remaining width to specific column by setting GridColumn.ColumnWidthMode property as like below.

<dataGrid:SfDataGrid x:Name="sfDataGrid"
                        AutoGenerateColumns="False"
                        ColumnWidthMode="AutoLastColumnFill"
                        ItemsSource="{Binding OrdersDetails}">            
            <dataGrid:SfDataGrid.Columns>
                <dataGrid:GridTextColumn HeaderText="Order ID" MappingName="OrderID" ColumnWidthMode="AutoLastColumnFill" />
                <dataGrid:GridTextColumn HeaderText="Customer ID" MappingName="Customer ID" />               
                <dataGrid:GridTextColumn HeaderText="Order Date" MappingName="OrderDate" />
                <dataGrid:GridTextColumn HeaderText="Unit Price" MappingName="UnitPrice" />
                <dataGrid:GridTextColumn HeaderText="Ship City" MappingName="ShipCity" />
                <dataGrid:GridTextColumn MappingName="Country" />
            </dataGrid:SfDataGrid.Columns>
</dataGrid:SfDataGrid>
this.sfDataGrid.ColumnWidthMode = ColumnWidthMode.AutoLastColumnFill;
this.sfDataGrid.Columns["OrderID"].ColumnWidthMode = ColumnWidthMode.AutoLastColumnFill;

Specific Column in WinUI DataGrid Fills Remaining Width

Refreshing autosize calculation at runtime

You can refresh the autosize calculation at runtime by calling SfDataGrid.ColumnSizer.Refresh method.
DataGrid support to recalculates the column auto width by calling reset methods of ColumnSizer. ColumnSizer.ResetAutoCalculationforAllColumns method reset widths to all columns. ColumnSizer.ResetAutoCalculation method reset the width to particular column.

NOTE

The ColumnSizer.ResetAutoCalculationforAllColumns or ColumnSizer.ResetAutoCalculation methods applicable for Auto, AutoWithLastColumnFill, AutoLastColumnFill, SizeToCells types.

For example, you can refresh all the column’s width based on the cell contents of newly added records at runtime.

var viewModel = this.sfDataGrid.DataContext as OrderInfoViewModel;
viewModel.OrdersDetails.Add(new OrderInfo() { 
    OrderID = 10011,
    UnitPrice = 34,
    Quantity = 20,
    OrderDate = DateTime.Now,
    ShipAddress = "I.de Margarita,Venezuela",
    ShipCity = "Venezuela"
    });
this.sfDataGrid.ColumnSizer.ResetAutoCalculationforAllColumns();
this.sfDataGrid.ColumnSizer.Refresh();

Resetting column width to apply autosize calculation

When the width of the column is explicitly defined or column is resized, then column width is not changed based on ColumnSizer. You can reset GridColumn.Width by setting double.NaN to apply column width based on column sizer.

foreach (var column in sfDataGrid.Columns)
{
    if (!double.IsNaN(column.Width))
        column.Width = double.NaN;
}
this.sfDataGrid.ColumnSizer.Refresh();

Customizing built-in column auto-sizing logic

SfDataGrid process column sizing operations in DataGridColumnSizer class. You can customize the column sizing operations by overriding DataGridColumnSizer and set it to SfDataGrid.ColumnSizer.

this.sfDataGrid.ColumnSizer = new ColumnSizerExt(sfDataGrid);

public class ColumnSizerExt : DataGridColumnSizer
{
    public ColumnSizerExt(SfDataGrid dataGrid)
        : base(dataGrid)
    {

    }

    // Calculate Width for column when ColumnSizer is SizeToCells.
    protected override double CalculateCellWidth(GridColumn column, bool setWidth = true)
    {
        return base.CalculateCellWidth(column, setWidth);
    }

    //Calculate Width for the column when ColumnSizer is SizeToHeader
    protected override double CalculateHeaderWidth(GridColumn column, bool setWidth = true)
    {
        return base.CalculateHeaderWidth(column, setWidth);
    }
}

Auto width calculation based on font settings

By default, the ColumnSizer calculates column’s width based on fixed FontSize, FontFamily, Margin,SortIconWidth, FilterIconWidth. You can change the calculation by customized settings.

Changing sort and filter icon width

You can change the filter icon and sort icon widths for column width calculation by setting ColumnSizer.SortIconWidth and ColumnSizer.FilterIconWidth properties.

sfDataGrid.ColumnSizer.SortIconWidth = 20;
sfDataGrid.ColumnSizer.FilterIconWidth = 20;

Changing font settings for DataGrid

You can change the font settings for column width calculation by setting ColumnSizer.FontSize, ColumnSizer.FontFamily and ColumnSizer.Margin properties. This settings will be considered for all columns.

this.sfDataGrid.ColumnSizer.FontSize = 10.0;
this.sfDataGrid.ColumnSizer.FontFamily = new FontFamily("TimesNewRoman");
this.sfDataGrid.ColumnSizer.Margin = ThicknessHelper.FromLengths(9, 3, 1, 3);

Changing font settings for one column

You can change the font setting for one column width calculation using DataGridColumnSizer.SetFontFamily, DataGridColumnSizer.SetFontSize and DataGridColumnSizer.SetMargin static methods of DataGridColumnSizer to GridColumn.

var gridColumn = this.sfDataGrid.Columns[0];
DataGridColumnSizer.SetFontFamily(gridColumn, new FontFamily("TimesNewRoman"));
DataGridColumnSizer.SetFontSize(gridColumn, 10.0);
DataGridColumnSizer.SetMargin(gridColumn, ThicknessHelper.FromLengths(9, 3, 1, 3));

Star column sizer ratio support

You can customize the ColumnWidthMode.Star width calculation logic by overriding SetStarWidth method of DataGridColumnSizer.

For example, you can calculate the column width, with specified ratios instead of dividing equal width for all columns in Star calculation using ColumnRatio attached property.

public static class StarRatio
{

    public static int GetColumnRatio(DependencyObject obj)
    {
        return (int)obj.GetValue(ColumnRatioProperty);
    }

    public static void SetColumnRatio(DependencyObject obj, int value)
    {
        obj.SetValue(ColumnRatioProperty, value);
    }

    public static readonly DependencyProperty ColumnRatioProperty = DependencyProperty.RegisterAttached("ColumnRatio", typeof(int), typeof(StarRatio), new PropertyMetadata(1, null));
}

Below code to define the star width calculation based on the ColumnRatio.

//Assign the customized GridColumnSizerExt to SfDataGrid.ColumnSizer
this.sfDataGrid.ColumnSizer = new GridColumnSizerExt(sfDataGrid);
public class GridColumnSizerExt : DataGridColumnSizer
{
    public GridColumnSizerExt(SfDataGrid dataGrid)
        : base(dataGrid)
    {

    }
    
    protected override void SetStarWidth(double remainingColumnWidth, IEnumerable<GridColumn> remainingColumns)
    {
        var removedColumn = new List<GridColumn>();
        var columns = remainingColumns.ToList();
        var totalRemainingStarValue = remainingColumnWidth;
        double removedWidth = 0;
        bool isRemoved;
    
        while (columns.Count > 0)
        {
            isRemoved = false;
            removedWidth = 0;
            var columnsCount = 0;

            columns.ForEach((col) =>
            {
                columnsCount += StarRatio.GetColumnRatio(col);
            });

            double starWidth = Math.Floor((totalRemainingStarValue / columnsCount));
            var column = columns.First();
            starWidth *= StarRatio.GetColumnRatio(column);
            double computedWidth = SetColumnWidth(column, starWidth);

            if (starWidth != computedWidth && starWidth > 0)
            {
                isRemoved = true;
                columns.Remove(column);

                foreach (var remColumn in removedColumn)
                {

                    if (!columns.Contains(remColumn))
                    {
                            removedWidth += remColumn.ActualWidth;
                            columns.Add(remColumn);
                    }
                }
                removedColumn.Clear();
                totalRemainingStarValue += removedWidth;
            }

            totalRemainingStarValue = totalRemainingStarValue - computedWidth;

            if (!isRemoved)
            {
                columns.Remove(column);

                if (!removedColumn.Contains(column))
                    removedColumn.Add(column);
            }
        }
    }
}

Below code uses the ColumnRatio to apply the defined star width for each column.

<dataGrid:SfDataGrid  x:Name="sfDataGrid"
                        AllowSorting="True"
                        AllowEditing="True"
                        AutoGenerateColumns="False"
                        ColumnWidthMode="Star"
                        ItemsSource="{Binding OrdersDetails}">
    <dataGrid:SfDataGrid.Columns>
        <dataGrid:GridTextColumn HeaderText="Order ID" MappingName="OrderID" local:StarRatio.ColumnRatio="1"/>
        <dataGrid:GridTextColumn HeaderText="Customer ID" MappingName="Customer ID" local:StarRatio.ColumnRatio="1"/>
        <dataGrid:GridTextColumn HeaderText="Order Date" MappingName="OrderDate" local:StarRatio.ColumnRatio="1"/>
        <dataGrid:GridTextColumn   HeaderText="Unit Price" MappingName="Unit Price" local:StarRatio.ColumnRatio="1"/>
        <dataGrid:GridTextColumn   HeaderText="Ship City" MappingName="ShipCity" local:StarRatio.ColumnRatio="2" />
        <dataGrid:GridTextColumn MappingName="Country" local:StarRatio.ColumnRatio="2"/>
    </dataGrid:SfDataGrid.Columns>
</dataGrid:SfDataGrid>

WinUI DataGrid displays ColumnRatio Column Width

Change the width of DataGrid ComboBoxColumn based on it’s ItemsSource

By default, the ColumnWidthMode calculates auto width based on the column content. You can change the auto width calculation for GridComboBoxColumn based on its items source by overriding the CalculateCellWidth virtual method.

Below code creates CustomColumnSizer to change the width of GridComboboxColumn and set to SfDataGrid.ColumnSizer.

this.sfDataGrid.ColumnSizer = new GridColumnSizerExt(sfDataGrid);

public class GridColumnSizerExt : DataGridColumnSizer
{
    public GridColumnSizerExt(SfDataGrid dataGrid)
    : base(dataGrid)
    {

    }

    protected override double CalculateCellWidth(GridColumn column, bool setWidth = true)
    {
        //Customizing width calculation for GridComboBoxColumn
        if (column is GridComboBoxColumn)
        {
            //Get the width of the corresponding GridColumn
            double colWidth = column.Width;

            //Get the Source collection from the corresponding GridComboBoxColumn items source
            var source = (column as GridComboBoxColumn).ItemsSource;

            //Initialize the below field for storing length                
            string maximumComboItemsText = string.Empty;

            //Get the column width and row height
            var clientSize = new Size(colWidth, DataGrid.RowHeight);

            //Calculate the maximum length for each combo box items and store maximum length
            foreach (var comboItems in source)
            {
                string comboItemText = (string)comboItems;
                if (maximumComboItemsText.Length < comboItemText.Length)
                    maximumComboItemsText = comboItemText;
            }

            //Get the size for maximum ComboBoxItems's text and returned the measured width as a column width of that column
            var measureSize = MeasureText(clientSize, maximumComboItemsText, column, null, GridQueryBounds.Width);

            return measureSize.Width;
        }
        //Default column width calculation performed other than GridComboBoxColumn
        return base.CalculateCellWidth(column, setWidth);
        }
    }