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Better ListView Tip: How to Draw Custom Selection

Customized item selection.

Customized item selection.

 

By default, Better ListView uses system theme for drawing selections.

To draw custom selection, you can use owner drawing capabilities of Better ListView:

C#

class CustomListView : BetterListView
{
    protected override void OnDrawItemBackground(BetterListViewDrawItemBackgroundEventArgs eventArgs)
    {
        base.OnDrawItemBackground(eventArgs);

        if (eventArgs.Item.Selected)
        {
            Brush brushSelection = new SolidBrush(Color.FromArgb(128, Color.LightGreen));
            eventArgs.Graphics.FillRectangle(brushSelection, eventArgs.ItemBounds.BoundsSelection);
            brushSelection.Dispose();
        }
    }

    protected override void OnDrawItem(BetterListViewDrawItemEventArgs eventArgs)
    {
        eventArgs.DrawSelection = false;

        base.OnDrawItem(eventArgs);

        if (eventArgs.Item.Selected)
        {
            eventArgs.Graphics.DrawRectangle(Pens.DarkGreen, eventArgs.ItemBounds.BoundsSelection);
        }
    }
}

Visual Basic

Class CustomListView
	Inherits BetterListView
	Protected Overrides Sub OnDrawItemBackground(eventArgs As BetterListViewDrawItemBackgroundEventArgs)
		MyBase.OnDrawItemBackground(eventArgs)

		If eventArgs.Item.Selected Then
			Dim brushSelection As Brush = New SolidBrush(Color.FromArgb(128, Color.LightGreen))
			eventArgs.Graphics.FillRectangle(brushSelection, eventArgs.ItemBounds.BoundsSelection)
			brushSelection.Dispose()
		End If
	End Sub

	Protected Overrides Sub OnDrawItem(eventArgs As BetterListViewDrawItemEventArgs)
		eventArgs.DrawSelection = False

		MyBase.OnDrawItem(eventArgs)

		If eventArgs.Item.Selected Then
			eventArgs.Graphics.DrawRectangle(Pens.DarkGreen, eventArgs.ItemBounds.BoundsSelection)
		End If
	End Sub
End Class

In the above code, we have created class CustomListView that inherits from BetterListView. We override OnDrawItemBackground and OnDrawItem methods to customize item background and item foreground drawing, respectively.

The OnDrawItemBackground method contains only check for whether the item is selected. If so, we draw selection background (filled rectangle in selection area).

The OnDrawItem method contains two things:

  1. Turn off  default selection.
  2. Draw custom selection border if the item is selected.

Drawbacks of drawing custom selections like this include using non-system theme, which can look ugly on various color schemes. By default, Better ListView always use the system theme, so the color consistency is ensured. You can, however, still use classes like SystemColors or SystemBrushes to ensure good look.

Another drawback is that you handle only two states of selection, i.e. selected and unselected state. This is sufficient for Classic Windows theme but there are several more states used on Windows Aero Theme, like “hot”, “focused and hot” or “hot and pressed”.

To allow these states, considerable coding need to be done.

In case you need this level of customization, please contact us for Custom Coding support.

 

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2 Responses to “Better ListView Tip: How to Draw Custom Selection”

  1. Claudiu says:

    Better list view is only for stupid developers and plase do not compare it with standard list view. Performance is an important think and betterlistview has no performance compared with list view. Make an loop with 100000 items for add to list and you will see ….

    • Libor Tinka says:

      We have balanced performance with features, this is a price for having fully managed control with rich features (tree items, multi-line text). If you want something extremely fast, faster than ListView, handling 100 000 000 items like a charm … use DOS text mode! :)

      We have happy customers who use Better ListView in complex systems like airline ticket booking and they are very intelligent people – I don’t think they are stupid developers.

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