Thank you for your sample code.

I find out that set the HeaderPlacement property to "OncePerGroupedRowIsland", so header check box does not work.

I'd like to make the grid have below functions that

 1) check and uncheck all rows when I click column header check box even after grouping

 2) check and uncheck all rows just in a group when I click group header check box

Hi,

Thank you for the reply.

The code was updating the cell values in the GroupByRowCheckBoxClicked (it also fires if the state of the checkbox was altered through code) event and it was doing it even when the state of the checkbox was Indeterminate. I have added a check so that it will set all checkboxes to false only if the state is Unchecked.

The header checkbox is in Indeterminate state because one of the cell should be checked (this was fixed in point 1). So when some cells but not all are checked the group by row checkbox should go to state Indeterminate. This is at least how the header checkbox behaves and I decided to implement it so both checkboxes work the same way. Let me know if you want to change this.

I have attached the modified sample. Feel free to modify it based on your custom needs.

Please let me know if you have any additional questions.

Can you solve the problem that I found out?

I don't know why the check boxes suddenly disappeared.

Hello,

Thank you for the feedback.

I tried to reproduce this in the sample and I didn’t notice such thing. Can you be more specific with the steps to reproduce this? Can this be reproduced in my sample or you noticed it in your project? Does the amount of group by columns matter (does it happen when there is only one group by column, or you need more)? Does the speed with which you expand/collapse the groups matter? It would be really helpful, if you are able to make a small video demonstrating how to reproduce the issue.

I am looking forward to your reply.

I found out the problems in your sample code.

I can't exactly tell you the way to reproduce the problem because it is occurred randomly.

However, I tried to reproduce it, it's always occurred.

In your sample code, there are four groups.

I randomly expand and collapse four groups such as 1 expand, 2 expand, 1 collapse, 3 expand, 1 expand, 4 expand, 4 collapse, 2 collapse....

When I do these works repeatedly, suddenly the check box of 3 or 4 groups disappear and I can't recreate the check box in that groups.

I think that if you repeatedly do it 3~40 times, you can find out the problem.

p.s In this forum, I can not paste picture, which I captured, from the clipboard.

     Because of the secret policy, I can't upload files, such as .png or .jpg, from the computer.