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ListView.DrawItem Event

  • Reference

Definition

Namespace:
System.Windows.Forms
Assembly:
System.Windows.Forms.dll

Occurs when a ListView is drawn and the OwnerDraw property is set to true.

public:
 event System::Windows::Forms::DrawListViewItemEventHandler ^ DrawItem;
public event System.Windows.Forms.DrawListViewItemEventHandler DrawItem;
public event System.Windows.Forms.DrawListViewItemEventHandler? DrawItem;
member this.DrawItem : System.Windows.Forms.DrawListViewItemEventHandler 
Public Custom Event DrawItem As DrawListViewItemEventHandler

Event Type

DrawListViewItemEventHandler

Examples

The following code example provides an implementation of a DrawItem event handler. For the complete example, see the OwnerDraw reference topic.

// Draws the backgrounds for entire ListView items.
private void listView1_DrawItem(object sender,
    DrawListViewItemEventArgs e)
{
    if ((e.State & ListViewItemStates.Selected) != 0)
    {
        // Draw the background and focus rectangle for a selected item.
        e.Graphics.FillRectangle(Brushes.Maroon, e.Bounds);
        e.DrawFocusRectangle();
    }
    else
    {
        // Draw the background for an unselected item.
        using (LinearGradientBrush brush =
            new LinearGradientBrush(e.Bounds, Color.Orange,
            Color.Maroon, LinearGradientMode.Horizontal))
        {
            e.Graphics.FillRectangle(brush, e.Bounds);
        }
    }

    // Draw the item text for views other than the Details view.
    if (listView1.View != View.Details)
    {
        e.DrawText();
    }
}

' Draws the backgrounds for entire ListView items.
Private Sub listView1_DrawItem(ByVal sender As Object, _
    ByVal e As DrawListViewItemEventArgs) _
    Handles listView1.DrawItem

    If Not (e.State And ListViewItemStates.Selected) = 0 Then

        ' Draw the background for a selected item.
        e.Graphics.FillRectangle(Brushes.Maroon, e.Bounds)
        e.DrawFocusRectangle()

    Else

        ' Draw the background for an unselected item.
        Dim brush As New LinearGradientBrush(e.Bounds, Color.Orange, _
            Color.Maroon, LinearGradientMode.Horizontal)
        Try
            e.Graphics.FillRectangle(brush, e.Bounds)
        Finally
            brush.Dispose()
        End Try

    End If

    ' Draw the item text for views other than the Details view.
    If Not Me.listView1.View = View.Details Then
        e.DrawText()
    End If

End Sub

Remarks

This event lets you customize the appearance of a ListView control using owner drawing. It is raised only when the OwnerDraw property is set to true. For more information about owner drawing, see the OwnerDraw property reference topic.

The DrawItem event can occur for each ListView item. When the View property is set to View.Details, the DrawSubItem and DrawColumnHeader events also occur. In this case, you can handle the DrawItem event to draw elements common to all items, such as the background, and handle the DrawSubItem event to draw elements for individual subitems, such as text values. You can also draw all items in the ListView control using only one of the two events, although this may be less convenient. To draw column headers in the details view, you must handle the DrawColumnHeader event.

Note

Because of a bug in the underlying Win32 control, the DrawItem event occurs without accompanying DrawSubItem events once per row in the details view when the mouse pointer moves over the row, causing anything painted in a DrawSubItem event handler to be painted over by a custom background drawn in a DrawItem event handler. See the example in the OwnerDraw reference topic for a workaround that invalidates each row when the extra event occurs. An alternative workaround is to put all your custom drawing code in a DrawSubItem event handler and paint the background for the entire item (including subitems) only when the DrawListViewSubItemEventArgs.ColumnIndex value is 0.

For more information about handling events, see Handling and Raising Events.

Applies to

See also