Open dropdown(in a datagrid view) items on a single click

Question

How can i avoid the double click on a DropDownButton used within a DataGridView? Right now I am able to view the drop down items within the DataGridView by clicking two or more times. First time it selects the cell and second time when I click on the DropDownButton arrow, it shows the list. How can I achieve the same in a single click?

Answer 1

You can achieve this by subscribing for the EditingControlShowing event of the grid and there for control of type ComboBox

ComboBox ctl = e.Control as ComboBox;
ctl.Enter -= new EventHandler(ctl_Enter);
ctl.Enter += new EventHandler(ctl_Enter);

And in the Enter event, use the property

void ctl_Enter(object sender, EventArgs e)
{
    (sender as ComboBox).DroppedDown = true;
}

DroppedDown indicates as the name suggests whether the dropdown area is shown or not, so whenever the control is entered this will set it to true and display the items without the need of further clicks.

Answer 2

Set EditMode property of the DataGridView to EditOnEnter: link

DataGridView.EditMode - Gets or sets a value indicating how to begin editing a cell.

EditOnEnter - Editing begins when the cell receives focus.

Answer 3

The "set EditMode property of the DataGridView to EditOnEnter" worked for me, but I found another problem: user can't delete a row by just selecting and pressing DEL key. So, a google search gave me another way to do it. Just catch the event CellEnter and check if the cell is the appropriated type to perform appropriated action like this sample code:

private void Form_OnLoad(object sender, EventArgs e){
    dgvArmazem.CellEnter += new DataGridViewCellEventHandler(dgvArmazem_CellEnter);
}

void dgvArmazem_CellEnter(object sender, DataGridViewCellEventArgs e)
        {
            DataGridView dg = (DataGridView)sender;

            if (dg.CurrentCell.EditType == typeof(DataGridViewComboBoxEditingControl))
            {
                SendKeys.Send("{F4}");
            }
        }

Now the ComboBox drops down faster and the user still delete a row by selecting a row and pressing DEL key.

That's it.