Dynamic DropDown Size for RadPopupEditor
Environment
| Product Version | Product | Author |
|---|---|---|
| 2022.2.622 | RadPopupEditor for WinForms | Desislava Yordanova |
Description
The following tutorial demonstrates a sample approach how to size dynamically the drop down in RadPopupEditor. If the control is above the middle of the screen (vertically), the popup should open to the bottom and the height should be enough to reach the bottom of the screen. If the control is below the middle of the screen, the popup should open to the top and the height should reach the top of the screen.
Solution
Create a derivative of RadPopupEditorElement and override its GetPopupSize method. The returned size depends on the screen position of the control.
public class CustomPopupEditor : RadPopupEditor
{
public override string ThemeClassName
{
get
{
return typeof(RadPopupEditor).FullName;
}
}
protected override RadPopupEditorElement CreateElement()
{
return new CustomElement();
}
}
public class CustomElement : RadPopupEditorElement
{
protected override Size GetPopupSize(RadPopupControlBase popup, bool measure)
{
Point location = this.ElementTree.Control.PointToScreen(Point.Empty);
int height = 0;
if (location.Y >= Screen.PrimaryScreen.WorkingArea.Height / 2)
{
height = location.Y;
}
else
{
height = Screen.PrimaryScreen.WorkingArea.Height - location.Y - this.TextBoxElement.TextBoxItem.Size.Height * 2;
}
Size s = new Size(this.TextBoxElement.TextBoxItem.Size.Width, height);
return s;
}
}
Public Class CustomPopupEditor
Inherits RadPopupEditor
Public Overrides ReadOnly Property ThemeClassName As String
Get
Return GetType(RadPopupEditor).FullName
End Get
End Property
Protected Overrides Function CreateElement() As RadPopupEditorElement
Return New CustomElement()
End Function
End Class
Public Class CustomElement
Inherits RadPopupEditorElement
Protected Overrides Function GetPopupSize(ByVal popup As RadPopupControlBase, ByVal measure As Boolean) As Size
Dim location As Point = Me.ElementTree.Control.PointToScreen(Point.Empty)
Dim height As Integer = 0
If location.Y >= Screen.PrimaryScreen.WorkingArea.Height / 2 Then
height = location.Y
Else
height = Screen.PrimaryScreen.WorkingArea.Height - location.Y - Me.TextBoxElement.TextBoxItem.Size.Height * 2
End If
Dim s As Size = New Size(Me.TextBoxElement.TextBoxItem.Size.Width, height)
Return s
End Function
End Class