checked listview bug ???

[Tariq Ahmad]

hi,

i have a listview that displays checkboxes.
FullRowSelect is set to true and HideSelection is false.

i only want to allow a maximum of 3 checkboxes
to be checked.

i have some code in the _ItemCheck event that
counts the number of items already checked and if this
number =3 then displays an error message and
executes "e.NewValue = CheckState.Unchecked".

now, suppose i have 3 checkboxes checked.

if i select a row in the listview so that the whole row is highlighted
and click the checkbox my code in _ItemCheck is exected but the
checkbox still gets checked!

if i click another checkbox (but dont select the row first) then
my code in _ItemCheck is exected but the checkbox does not gets checked.

is this a bug? or is my understanding incorrect?

thnx.

t.

ps. i can post some sample code if this will help.

[Lion Shi]

Hello Tariq,

That is known issue of the ListView control. It is because if multiple
items were selected, we were firing onItemCheck for each item. But, since
we were creating a temp variable for ItemCheckEventArgs inside the foreach
loop, any change to this variable made by the onItemCheck event handler
were being discarded. So, when the handler specifies

e.NewValue = CheckState.Unchecked

This is not respected.

To workaround it, you can subclass ListView and override OnItemCheck to do
what you want.

I hope this information is helpful.

Best regards,

Lion Shi [MS]
MCSE, MCSD
Microsoft Support Engineer

This posting is provided "AS IS" with no warranties, and confers no rights.
You assume all risk for your use. 2001 Microsoft Corporation. All rights
reserved.
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From: "Tariq Ahmad" <tariq...@hotmail.com>
Subject: checked listview bug ???
Date: Mon, 25 Nov 2002 17:15:10 -0000
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