GridView.CustomDrawCell Event

Enables data cells to be painted manually.

Namespace: DevExpress.XtraGrid.Views.Grid

Assembly: DevExpress.XtraGrid.v18.1.dll

Declaration

C#

[DXCategory("CustomDraw")]
public event RowCellCustomDrawEventHandler CustomDrawCell

VB.NET

<DXCategory("CustomDraw")>
Public Event CustomDrawCell As RowCellCustomDrawEventHandler

Event Data

The CustomDrawCell event's data class is RowCellCustomDrawEventArgs. The following properties provide information specific to this event:

Property	Description
Appearance	Gets the painted element’s appearance settings. Inherited from CustomDrawEventArgs.
Bounds	Returns a value specifying limits for the drawing area. Inherited from CustomDrawEventArgs.
Cache	Provides methods to paint on drawing surfaces in GDI+ and DirectX modes. See DirectX hardware acceleration to learn more. Inherited from CustomDrawEventArgs.
Cell	Provides information on the painted cell.
CellValue	Gets the painted value or display text (depending on the event).
Column	Gets the column whose element is being painted.
DisplayText	Gets or sets the painted element’s display text.
Graphics	A GDI+ drawing surface. Use the CustomDrawEventArgs.Cache property instead if you enable the DirectX hardware acceleration. Inherited from CustomDrawEventArgs.
Handled	Gets or sets a value specifying whether an event was handled and that the default element painting is therefore not required. Inherited from CustomDrawEventArgs.
RowHandle	Gets the handle of a painted element’s row.

The event data class exposes the following methods:

Method	Description
DefaultDraw()	Performs default painting of an element. Inherited from CustomDrawEventArgs.

Remarks

The CustomDrawCell event is raised before a data cell is painted. The cell that is about to be painted is identified by the RowCellCustomDrawEventArgs.RowHandle and RowCellCustomDrawEventArgs.Column parameters.

See the Custom Painting Basics and Custom Painting Scenarios topics for information on using custom draw events.

Note

In some cases, a cell’s background may not be repainted by the default painting mechanism (when it is invoked). For instance, if you draw a line, this line may be visible even after the default rendering. However, this is not always true. For instance, if you handle the GridView.RowCellStyle event (in addition to the GridView.CustomDrawCell event) and customize the cell’s background color(s), custom drawing will be cleared and the cell’s background will be repainted by the default painting mechanism after your CustomDrawCell event handler is completed.

We do not recommend that you rely on this behavior, as it may change in the future.

Note

The control’s events designed to change the appearance or rendering of control elements must not be used to update cell values or to modify the control’s layout. Any inappropriate operation which causes a layout update, may break the normal control behavior.

Note

If you subscribe to this event at runtime, your event handler may not be called immediately. The event handler will be raised after the grid’s layout is changed. You can manually invoke the layout change action, and thus your CustomDrawCell event handler, by calling the BaseView.LayoutChanged method after the event subscription.

Example

The following code demonstrates how to use the CustomDrawCell event to re-paint cells that belong to the third Grid Column.

C#

using DevExpress.XtraGrid.Views.Grid;
using DevExpress.XtraGrid.Views.Base;

CustomDrawCell(gridControl1, gridView1);

public static void CustomDrawCell(GridControl gridControl, GridView gridView) {
    // Handle this event to paint cells manually
    gridView.CustomDrawCell += (s, e) => {
        if (e.Column.VisibleIndex != 2) return;
        e.Cache.FillRectangle(Color.Salmon, e.Bounds);
        e.Appearance.DrawString(e.Cache, e.DisplayText, e.Bounds);
        e.Handled = true;
    };
}

VB.NET

Imports DevExpress.XtraGrid.Views.Grid
Imports DevExpress.XtraGrid.Views.Base

CustomDrawCell(gridControl1, gridView1)

Shared Sub CustomDrawCell(ByVal gridControl As GridControl, ByVal gridView As GridView)
    ' Handle this event to paint cells manually
    AddHandler gridView.CustomDrawCell,
        Sub(s, e)
            If e.Column.VisibleIndex <> 2 Then
                Return
            End If
            e.Cache.FillRectangle(Color.Salmon, e.Bounds)
            e.Appearance.DrawString(e.Cache, e.DisplayText, e.Bounds)
            e.Handled = True
        End Sub
End Sub

Related GitHub Examples

The following code snippets (auto-collected from DevExpress Examples) contain references to the CustomDrawCell event.

Note

The algorithm used to collect these code examples remains a work in progress. Accordingly, the links and snippets below may produce inaccurate results. If you encounter an issue with code examples below, please use the feedback form on this page to report the issue.

C#

how-to-draw-a-rectangle-around-selected-cells-and-implement-a-copy-paste-functionality-e1603/CS/Q212929/CellSelectionHelper.cs#L216

    fView.KeyDown += new KeyEventHandler(OnGridViewKeyDown);
    fView.CustomDrawCell += new RowCellCustomDrawEventHandler(OnGridViewCustomDrawCell);
}

how-to-highlight-cells-that-were-changed-in-a-grid-with-a-different-color-for-some-time-e2441/CS/CellChangedHighlight/CellToPaint.cs#L20

this.view = gridView;
view.CustomDrawCell += new RowCellCustomDrawEventHandler(OnCustomDrawCell);

how-to-highlight-the-next-or-previous-search-result-in-the-grid-t367497/CS/WindowsFormsApplication2/FindHelper.cs#L145

if (view == null) return;
view.CustomDrawCell -= CustomDrawCell;
if(subscribe)

how-to-show-an-input-prompt-in-the-auto-filter-row-like-in-new-item-row-e3407/CS/MyAutoFilterRowHelper.cs#L22

 _AutoFilterText = text;
 view.CustomDrawCell += view_CustomDrawCell;
// view.GridControl.Paint += GridControl_Paint;

how-to-display-buttons-with-different-captions-in-different-rows-of-gridview-e4024/CS/CS/WindowsApplication1/CustomEditor/ButtonEditCustomCaptionHelper.cs#L24

_Column = column;
view.CustomDrawCell += view_CustomDrawCell;
view.ShownEditor += new EventHandler(view_ShownEditor);

VB.NET

hot-tracking-rows-similar-to-windows-7-style-e3803/VB/E3803/HotTrackHelper.vb#L22

_view = view
AddHandler _view.CustomDrawCell, AddressOf _view_CustomDrawCell
AddHandler _view.MouseMove, AddressOf _view_MouseMove

how-to-draw-a-rectangle-around-selected-cells-and-implement-a-copy-paste-functionality-e1603/VB/Q212929/CellSelectionHelper.vb#L248

    AddHandler fView.KeyDown, AddressOf OnGridViewKeyDown
    AddHandler fView.CustomDrawCell, AddressOf OnGridViewCustomDrawCell
End Sub

how-to-highlight-cells-that-were-changed-in-a-grid-with-a-different-color-for-some-time-e2441/VB/CellChangedHighlight/CellToPaint.vb#L19

Me.view = gridView
AddHandler view.CustomDrawCell, AddressOf OnCustomDrawCell

how-to-use-different-colored-progressbar-in-gridcontrol-e3193/VB/ColoredProgressBar/SingleRepositoryProgressBar.vb#L20

    AddHandler View.ShownEditor, AddressOf View_ShownEditor
    AddHandler View.CustomDrawCell, AddressOf View_CustomDrawCell
End Sub

how-to-highlight-the-next-or-previous-search-result-in-the-grid-t367497/VB/FindHelper.vb#L137

End If
RemoveHandler view.CustomDrawCell, AddressOf CustomDrawCell
If subscribe Then