Please use the following code snippet. The user should be allowed to resize the drop down within the specified range as it is illustrated in the gif file:
RadDateTimePickerCalendar calBehavior = this.radDateTimePicker1.DateTimePickerElement.CurrentBehavior as RadDateTimePickerCalendar;
calBehavior.DropDownSizingMode = SizingMode.UpDownAndRightBottom;
calBehavior.DropDownMinSize = new Size(400, 400);
calBehavior.DropDownMaxSize = new Size(600, 600);
Currently, the user is allowed to shrink the width, but not the height.
Workaround:
public RadForm1()
{
InitializeComponent();
//this.radDateTimePicker1.CalendarSize = new Size(500, 500);
RadDateTimePickerCalendar calBehavior = this.radDateTimePicker1.DateTimePickerElement.CurrentBehavior as RadDateTimePickerCalendar;
calBehavior.DropDownSizingMode = SizingMode.UpDownAndRightBottom;
calBehavior.DropDownMinSize = new Size(400, 400);
calBehavior.DropDownMaxSize = new Size(600, 600);
this.radDateTimePicker1.Opened+=radDateTimePicker1_Opened;
}
private void radDateTimePicker1_Opened(object sender, EventArgs e)
{
RadDateTimePickerCalendar calBehavior = this.radDateTimePicker1.DateTimePickerElement.CurrentBehavior as RadDateTimePickerCalendar;
calBehavior.PopupControl.MinimumSize= calBehavior.DropDownMinSize;
}