VGridControlBase.CustomDrawRowHeaderIndent Event

Enables row header indents to be painted manually.

Namespace: DevExpress.XtraVerticalGrid

Assembly: DevExpress.XtraVerticalGrid.v20.1.dll

Declaration

public event CustomDrawRowHeaderIndentEventHandler CustomDrawRowHeaderIndent
Public Event CustomDrawRowHeaderIndent As CustomDrawRowHeaderIndentEventHandler

Event Data

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

Property Description
Appearance Gets the painted element's appearance settings. Inherited from CustomDrawEventArgs.
Bounds Gets a value specifying limits for the drawing area. Inherited from CustomDrawEventArgs.
Cache Gets an object which specifies the storage for the most used pens, fonts and brushes. Inherited from CustomDrawEventArgs.
CategoryIndents Gets a collection of category indents to be painted.
Graphics Gets an object used to paint. Inherited from CustomDrawEventArgs.
Handled Gets or sets a value specifying whether an event was handled, if handled, default actions are not required. Inherited from CustomDrawEventArgs.
IsRightToLeft Gets a value indicating whether the VGridControl's elements are aligned to support locales using right-to-left fonts. Inherited from CustomDrawEventArgs.
ObjectArgs Gets an object containing information about the painted element. Inherited from CustomDrawEventArgs.
Painter Gets the painter object that provides the default element's painting mechanism. Inherited from CustomDrawEventArgs.
Properties Provides properties specific to the row being custom painted. Inherited from CustomDrawRowEventArgs.
Row Gets the row whose element is to be drawn. Inherited from CustomDrawRowEventArgs.
RowIndents Gets a collection of row indents that are going to be painted.

Remarks

The CustomDrawRowHeaderIndent event is raised before a row header indent is painted. The row where the processed indent resides can be obtained via the event parameter's CustomDrawRowEventArgs.Row property. The CustomDrawRowHeaderIndentEventArgs.CategoryIndents and CustomDrawRowHeaderIndentEventArgs.RowIndents parameters provide access to the collections of category and row indents. Individual indents can be accessed using index notation.

The CustomDrawRowHeaderIndent event can be used for two purposes:

  • To manually paint all or only particular row header indents. Note that you need to set the CustomDrawEventArgs.Handled parameter to true to indicate that the default painting is not required for the indent.
  • Change the indent's appearance settings and leave the CustomDrawEventArgs.Handled parameter set to false. This will paint the row header indent using the default mechanism but with modified settings.
IMPORTANT

Do not change cell values, modify the control's layout, or change the control's object model in the events used for custom control painting. Actions that update the layout can cause the control to malfunction.

Examples

The following sample code handles the VGridControlBase.CustomDrawRowHeaderCell and VGridControlBase.CustomDrawRowHeaderIndent events to custom paint the focused row header and its indents. If the focused row is a category row, it is painted in the default manner.

The image below shows the result.

CustomDraw_Focused_property

using System.Drawing.Drawing2D;
using DevExpress.XtraVerticalGrid.ViewInfo;
using DevExpress.XtraVerticalGrid.Events;

private void vGridControl1_CustomDrawRowHeaderCell(object sender, 
CustomDrawRowHeaderCellEventArgs e) {
     if(e.Row.XtraRowTypeID != 0 && e.Focused) {
        // Creates the brush which is used to fill the background of row headers.
        using(var backBrush = new LinearGradientBrush(e.Bounds, Color.Orange,
            e.Appearance.BackColor2, LinearGradientMode.Vertical))
            e.Cache.FillRectangle(backBrush, e.Bounds);
        // Paints the row header's caption.
        e.Cache.DrawString(e.Caption, e.Appearance.Font, Brushes.DarkBlue,
            e.CaptionRect, e.Appearance.GetStringFormat());
        // Paints the row header's image.
        e.Cache.DrawImage(imageList1.Images[0], e.ImageRect);
        e.Handled = true;
    }
}

private void vGridControl1_CustomDrawRowHeaderIndent(object sender, 
CustomDrawRowHeaderIndentEventArgs e) {
    VGridControl grid = sender as VGridControl;
    if(e.Row.XtraRowTypeID == 0)
        return;
    if(e.Row == grid.FocusedRow) {
        // Fills the category indent's background.
        foreach(IndentInfo indInfo in e.CategoryIndents)
            using(var categoryIndentBrush = new LinearGradientBrush(indInfo.Bounds,
                    indInfo.Style.BackColor, indInfo.Style.BackColor,
                    LinearGradientMode.Vertical))
                e.Cache.FillRectangle(categoryIndentBrush, indInfo.Bounds);
        // Fills the row indent's background.
        if(e.RowIndents.Count - 1 > -1) {
            for(int i = 0; i < e.RowIndents.Count - 1; i++)
                using(var rowIndentBrush = new LinearGradientBrush(e.RowIndents[i].Bounds,
                        e.RowIndents[i].Style.BackColor, e.RowIndents[i].Style.BackColor2,
                        LinearGradientMode.Vertical))
                    e.Cache.FillRectangle(rowIndentBrush, e.RowIndents[i].Bounds);
            // Creates the brush which is used to fill the background of row indents.
            using(var backBrush = new LinearGradientBrush(e.Bounds, Color.Orange,
            e.Appearance.BackColor2, LinearGradientMode.Vertical))
                e.Cache.FillRectangle(backBrush, e.RowIndents[e.RowIndents.Count - 1].Bounds);
        }
        e.Handled = true;
    }
}
See Also