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Line Separator

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ComboBox and ListBox (obsolete as of Q2 2010)

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8 Answers, 1 is accepted

answered on 16 Jan 2014, 04:38 AM

Hi,

I do have a workaround for the problem where item separator needed in combo-box list to break down the items logically.

Please follow underneath steps to achieve the same-

Using below solution item separator can be applied at any preferred position in combo-box list-

1. Event DropDownOpened can be used to disable the item which enforces logical separation of items present in the combo-box and set item ToolTip Text to null since separator doesn't need to be on item tooltip.

2. KeyDown Event is used to identify the navigation of Arrow Keys( Up and Down) and ensures the separator should not be selected by any means.

void comboBox3_DropDownOpened(object sender, EventArgs e)
{
foreach (var item in comboBox3.Items)
{
if (item.Text.Contains("---"))
{
item.Enabled = false;
item.ToolTipText = null;

}
}

void comboBox3_KeyDown(object sender, KeyEventArgs e)
{
if (e.KeyValue == 38 || e.KeyValue == 40)
{
RadItem selectedItem = comboBox3.SelectedItem as RadItem;
if (selectedItem != null)
{
if (selectedItem.Text.Contains("---"))
{
int currentIndex = comboBox3.SelectedIndex;
int itemsCount = comboBox3.Items.Count - 1;

if (e.KeyValue == 40) //KeyDown
{
if (currentIndex != itemsCount)
currentIndex += 1;
else
currentIndex -= 1;
}
else if (e.KeyValue == 38)//KeyUp
currentIndex -= 1;

if (currentIndex != 0)
{
comboBox3.SelectedIndex = currentIndex;
selectedItem.ForceReApplyStyle();
}

}
}
}
}

This may help!!!!!

Note : Above solution addresses the problem in Version 8.2.0.0

Best Regards
Vinod

answered on 16 Jan 2014, 06:43 AM

Amended the solution for consecutive item separators.

void comboBox3_KeyDown(object sender, KeyEventArgs e)
{
this.SetNextOrPreviousElements(e);
}

void SetNextOrPreviousElements(KeyEventArgs e)
{
if (e.KeyValue == 38 || e.KeyValue == 40)
{
RadItem selectedItem = comboBox3.SelectedItem as RadItem;
if (selectedItem != null)
{
selectedItem.ForceReApplyStyle();

if (selectedItem.Text.Contains("----"))
{
int nextOrPrevious = 0;
int currentIndex = comboBox3.SelectedIndex;
int itemsCount = comboBox3.Items.Count - 1;

while (true) // For consecutive Item separators
{
if (e.KeyValue == 40) //KeyDown
{
if (currentIndex < itemsCount)
{
if ((comboBox3.Items[currentIndex] as RadItem).Text.Contains("----"))
{
currentIndex += 1;
nextOrPrevious++;
}
else
break;
}
else
{
currentIndex -= nextOrPrevious + 1;
break;
}
}

else if (e.KeyValue == 38)//KeyUp
{
if (currentIndex > -1)
{
if ((comboBox3.Items[currentIndex] as RadItem).Text.Contains("----"))
{
currentIndex -= 1;
nextOrPrevious++;
}
else
break;
}
else
{
currentIndex += nextOrPrevious + 1;
break;
}
}
}
comboBox3.SelectedIndex = currentIndex;
selectedItem.ForceReApplyStyle();
}
}
}
}

void comboBox3_DropDownOpened(object sender, EventArgs e)
{
foreach (var item in comboBox3.Items)
{
if (item.Text.Contains("----"))
{
item.Enabled = false;
item.ToolTipText = null;

}
}
}

Thanks!!!!!