Triggering a checkbox value changed event in DataG

Question

I have a grid view that has a check box column, and I want to trigger a drawing event as soon as the value of the cell is toggled. I tried the ValueChaged and the CellEndEdit and BeginEdit, and chose the selection mode as CellSelect. As for the the first 2 events, the event was triggered upon the finishing of the edit mode, like moving out of the current cell, or going back and forth. It's just a weird behavior.

Is there anything that triggers the event on the grid view as soon as the cell value is changed?

Answer 1

"EditingControlShowing" event doesn't fire on checkbox value change. Because display style of the checkbox cell doesn't not change.

The workaround i have used is as below. (I have used CellContentClick event)

    private void gGridView1_CellContentClick(object sender, DataGridViewCellEventArgs e)
    {
        if (string.Compare(gGridView1.CurrentCell.OwningColumn.Name, "CheckBoxColumn") == 0)
        {
            bool checkBoxStatus = Convert.ToBoolean(gGridView1.CurrentCell.EditedFormattedValue);
            //checkBoxStatus gives you whether checkbox cell value of selected row for the
            //"CheckBoxColumn" column value is checked or not. 
            if(checkBoxStatus)
            {
                //write your code
            }
            else
            {
               //write your code
            }
        }
    }

The above has worked for me. Please let me know if need more help.

Answer 2

I found a combination of the first two answers gave me what I needed. I used the CurrentCellDirtyStateChanged event and inspected the EditedFormattedValue.

private void dgv_CurrentCellDirtyStateChanged(object sender, EventArgs e)
{
   DataGridView dgv = (DataGridView)sender;
   DataGridViewCell cell = dgv.CurrentCell;
   if (cell.RowIndex >= 0 && cell.ColumnIndex == 3) // My checkbox column
     {
        // If checkbox checked, copy value from col 1 to col 2
        if (dgv.Rows[cell.RowIndex].Cells[cell.ColumnIndex].EditedFormattedValue != null && dgv.Rows[cell.RowIndex].Cells[cell.ColumnIndex].EditedFormattedValue.Equals(true))
        {
           dgv.Rows[cell.RowIndex].Cells[1].Value = dgv.Rows[cell.RowIndex].Cells[2].Value;
        }
     }
}

Answer 3

Working with an unbound control (ie I manage the content programmatically), without the EndEdit() it only called the CurrentCellDirtyStateChanged once and then never again; but I found that with the EndEdit() CurrentCellDirtyStateChanged was called twice (the second probably caused by the EndEdit() but I didn't check), so I did the following, which worked best for me:

    bool myGridView_DoCheck = false;
    private void myGridView_CurrentCellDirtyStateChanged(object sender, EventArgs e)
    {
        if (!myGridView_DoCheck)
        {
            myGridView_DoCheck = true;
            myGridView.EndEdit();
            // do something here
        }
        else
            myGridView_DoCheck = false;
    }

Answer 4

I use the CellContentClick event, which makes sure the user clicked the checkbox. It DOES fire multiple times even if the user stays in the same cell. The one issue is that the Value does not get updated, and always returns "false" for unchecked. The trick is to use the .EditedFormattedValue property of the cell instead of the Value property. The EditedFormattedValue will track with the check mark and is what one wishes the Value had in it when the CellContentClick is fired.

No need for a timer, no need for any fancy stuff, just use CellContentClick event and inspect the EditedFormattedValue to tell what state the checkbox is going into / just went into. If EditedFormattedValue = true, the checkbox is getting checked.

Answer 5

I had the same issue, but came up with a different solution:

If you make the column or the whole grid "Read Only" so that when the user clicks the checkbox it doesn't change value.

Fortunately, the DataGridView.CellClick event is still fired. In my case I do the following in the cellClick event:

if (jM_jobTasksDataGridView.Columns[e.ColumnIndex].CellType.Name == "DataGridViewCheckBoxCell")

But you could check the column name if you have more than one checkbox column.

I then do all the modification / saving of the dataset myself.

Answer 6

I found a simple solution.

Just change the cell focus after click on cell.

private void DGV_CellContentClick(object sender, DataGridViewCellEventArgs e)
{
    if (e.ColumnIndex == "Here checkbox column id or name") {
        DGV.Item(e.ColumnIndex, e.RowIndex + 1).Selected = true;
        //Here your code

    }
}

Don't forget to check if the column of your (ckeckbox + 1) index exist.