>I am using a grid control to display values from a table.
>The grid has 5 columns. The first one contains a container class which has a checkbox control. The next three columns contain table data. The last one is used to display a string which appears only when the checkbox in the first column is selected.
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>The problem is that when I check a checkbox, the string does not always appear in the corresponding text field in the fifth column. I have tried setting the sparse property of the fifth column but this usually results in the string being displayed in all the textfields in the column when I select the checkbox. When I deselect the checkbox all the strings disappear in the column.

I guess the problem is ControlSource of the fifth column. It looks that it should be some expression depending on logical value of the first? field. This case it should work, the only thing that you should refresh grid, column or textbox5 in Checkbox.valid.