4

I have a DataGridView that loads data from a DataTable, along with an unbound column of DataGridViewCheckBoxCells. The rows in the DataGridView are compared with a separate DataTable with values the user has saved, and if there is a match, the checkbox for that row should check.

Here is the code that compares the values and sets the checkbox value to 'true':

foreach (int j in selectedObjectives)
{
    foreach (DataGridViewRow r in dgvObjectives.Rows)
    {
        if (j == Convert.ToInt32(r.Cells["ObjectiveID"].Value))
        {
            dgvObjectives.CurrentCell = r.Cells["Select"];      
            ((DataGridViewCheckBoxCell)r.Cells["Select"]).Value = true;
            //dgvObjectives.InvalidateCell(r.Cells["Select"]);
            //dgvObjectives.EndEdit();
            //dgvObjectives.CommitEdit(DataGridViewDataErrorContexts.Commit);

        }
        if (Convert.ToInt32(r.Cells["ObjectiveID"].Value) == selectedIndex)
        {
            r.Selected = true;
        }
    }
}

When I call the method to perform this action during the form load private void WQMDrill_Load(object sender, EventArgs e), the values are set correctly, but the checkboxes do not check. However, when called after the form is finished loading, the code works perfectly. Unfortunately for me, I absolutely need for these to check during the load process.

I hope I was clear with my issue, any help on this matter would be greatly appreciated. As you can see, I have tried to invalidate the cell alone, as well as the entire DataGridView control. I also have

private void dgvObjectives_CurrentCellDirtyStateChanged(object sender, EventArgs e)
{
    if (this.dgvObjectives.CurrentCell.ColumnIndex == 0)
    {
        this.dgvObjectives.CommitEdit(DataGridViewDataErrorContexts.Commit);
    }
}

That doesn't fire during this time. Thank you.

abatishchev
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Megan
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  • The first snippet provided - is that exactly the code called in the form's `Load` event? Have you stepped through it to assure the values are getting set correctly during load? – AJ. Jun 30 '11 at 17:12
  • The form's `Load` event calls the method in which this code resides. I've stepped through the code, and the value for the checkbox is set properly, but the checkboxes fail to show themselves as checked. However, this method is also called when the user checks a box manually, and there it works perfectly. – Megan Jun 30 '11 at 17:26

3 Answers3

1

You can put your checkbox selection and update logic in the DataBindingComplete eventhandler, this fires after the FormLoad but before anything is displayed to the user.

David Hall
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  • Thank you for your response. I actually do set the cell's value as true, `((DataGridViewCheckBoxCell)r.Cells["Select"]).Value = true;` Maybe the line you were looking at was where I set the selected row as true. I'm going to try your suggestion with the DataBindingComplete. Thank you. – Megan Jun 30 '11 at 17:34
  • @Megan sorry about my first reply, actually read you code properly as I was editing my answer to provide code. So now I've just left the bit about DataBindingComplete, which should solve your problem. – David Hall Jun 30 '11 at 17:35
0

I'm not certain that calling CommitEdit will actually fire the Paint on the cell. Try handling the CellMouseUp event and firing EndEdit if the column is a checkbox column.

private void dgvObjectives_CellMouseUp(object sender, DataGridViewCellMouseEventArgs e)
{
    if (dgvObjectives.Columns[e.ColumnIndex] is DataGridViewCheckBoxColumn)
    {
        dgvObjectives.EndEdit();
    }
}
AJ.
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  • I'm not running into any issues when I click the check boxes manually, it's when I set the values programatically during the load method. If the user checks the boxes themselves, everything fires correctly and the checkbox changes state. However, when I load the program I need the checkboxes to automatically check, and that's where I'm running into the issue. But thank you for your response. – Megan Jun 30 '11 at 16:46
-1

I had the same problem, and tried a lot of different ways to deal with it, most failed, except when I tried this.BeginInvoke(new CDelegate()).

Scott
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shuke
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