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Change Focus from one datagridview to another while pressing down arrow key from first grid view cell

I have one datagridview and when I started typing on the first cell of gridview a new gridview will be shown as suggestion popup. I want to move focus to the popup gridview when pressing down an arrow key (the first gridview is in edit mode). Is there any Solution?

My issue get resolved.
The Arrow key is detected in PreviewKeyDown event.
Up, Down, Left and Right arrow keys do not trigger KeyDown event
private void PreviewKeyDown(object sender, PreviewKeyDownEventArgs e)
{
try
{
if (e.KeyCode == Keys.Down)
{
if (dgv_search.Visible == true)
{
dgv_search.Focus();
}
}
}
catch { }
}

Why the arrow keys don't work on vertical menuStrip?

I have a form with a menuStrip control (the layout VerticalStackWithOverflow). How could I enable the arrow keys to navigate this menu? Also how could I get the event of pressing Enter on the selected item?

I dont particularly know about that control, but the arrows and Enter dont work with TextBox either. The default key form moving between controls is Tab. You have to override the keypress event and add that feature by invoking SelectNextControl method something like this(in this case Enter)
private void keypressed(Object sender, KeyPressEventArgs e)
{
if (e.KeyChar == (char)Keys.Return)
{
this.SelectNextControl((Control) sender, true, true, true, true);
}
}

C#.NET Winform keypress event can't be cancelled

I have a (.NET 3.5) winform with a datagridview on which I added an event on checkboxes in the gridview like this. That post doesn't take into account that people can also use spacebar to toggle the checkbox, and because there is no CellKeyUp event like there is a CellMouseUp event, I enabled KeyPreview on the form and added this code to prevent toggling with the spacebar:
private void BulkOrderAddressDifferencesForm_KeyDown(object sender, KeyEventArgs e)
{
if (e.KeyCode == Keys.Space)
{
e.Handled = true;
e.SuppressKeyPress = true;
}
}
That works mostly, but there is a scenario in which the event is still handled, even though the debugger shows e.Handled is set to true.
If I click on a checkbox, then 1, then 2, I can toggle the checkbox with the space bar again. I have no idea why this happens, nor do I know how to fix it.

You can override Form's ProcessCmdKey method:
protected override bool ProcessCmdKey(ref Message msg, Keys keyData)
{
if (keyData == Keys.Space && checkBox1.Focused)
{
//instead of checkBox1.Focused condition, you check if your DataGridView contains focus and active cell is of checkBox type
return true;
}
return base.ProcessCmdKey(ref msg, keyData);
}

If the goal is to always react immediately when the check is changed, rather than preventing the use of the spacebar (Unless I'm mistaken, the problem is that the cellmouseup approach doesn't include (un)checking with space, rather than the goal is that space shouldn't be used at all? ), you could use the celldirtychanged approach instead of cellmouseup to catch both
//grid.CurrentCellDirtyStateChanged += grid_CurrentCellDirtyStateChanged;
void grid_CurrentCellDirtyStateChanged(object sender, EventArgs e)
{
if (grid.IsCurrentCellDirty)
{
var cell = grid.CurrentCell;
if (cell is DataGridViewCheckBoxCell)
{
grid.EndEdit();
//you could catch the cellvaluechanged event (or a bound listchanged event), or handle the change immediately here, e.g.:
//Console.WriteLine("{0} value changed to {1}", cell.OwningColumn.HeaderText, cell.Value);
}
}
}

How about the DataGridView.EditMode Property which
Gets or sets a value indicating how to begin editing a cell.
where
The default is EditOnKeystrokeOrF2.
and
All DataGridViewEditMode values except for EditProgrammatically allow a user to double-click a cell to begin editing it.
You have several options to choose from the DataGridViewEditMode Enumeration
EditOnEnter - Editing begins when the cell receives focus. This mode is useful when pressing the TAB key to enter values across a row, or when pressing the ENTER key to enter values down a column.
EditOnF2 - Editing begins when F2 is pressed while the cell has focus. This mode places the selection point at the end of the cell contents.
EditOnKeystroke - Editing begins when any alphanumeric key is pressed while the cell has focus.
EditOnKeystrokeOrF2 - Editing begins when any alphanumeric key or F2 is pressed while the cell has focus.
EditProgrammatically - Editing begins only when the BeginEdit method is called.
Update for DataGridViewCheckBoxCell:
It turns out that the DataGridViewEditMode does not work for the DataGridViewCheckBoxColumn.
In this case you can create your own DataGridViewCheckBoxColumn & DataGridViewCheckBoxCell. This allows you to override the cell's OnKeyUp event handler and reset the EditingCellFormattedValue if Space was pressed.
public class MyCheckBoxColumn : DataGridViewCheckBoxColumn
{
public MyCheckBoxColumn()
{
CellTemplate = new MyCheckBoxCell();
}
}
public class MyCheckBoxCell : DataGridViewCheckBoxCell
{
protected override void OnKeyUp(KeyEventArgs e, int rowIndex)
{
if (e.KeyCode == Keys.Space)
{
e.Handled = true;
if (EditingCellValueChanged)
{
// Reset the value.
EditingCellFormattedValue = !(bool)EditingCellFormattedValue;
}
}
else
{
base.OnKeyUp(e, rowIndex);
}
}
}
After you rebuild your project the new column should appear in the designer:

opening another window on press of enter button in datagridview

I have on large grid of data about 25000 rows. [Windows Application]
In that i am trying to implement functionality like, when i press enter key i can open new window. In that new window i am showing data for the record for which i pressed enter button in terms of text boxes and labels. But unfortunately i did not found any relative event for that. when i press enter button active selected row moves to the next record.
I also want to know if there is any functionality such that when i load the window[Grid] by default first record should get selected.
I have tried different events such as
private void gvTradeFile_RowEnter(object sender, DataGridViewCellEventArgs e)
{
splitPopUp objSplit = new splitPopUp();
objSplit.Show();
}
Not Worked.
private void gvTradeFile_Enter(object sender, EventArgs e)
{
splitPopUp objSplit = new splitPopUp();
objSplit.Show();
}
This also not worked.
I refered http://social.msdn.microsoft.com/Forums/en-US/csharpgeneral/thread/6a73013f-4440-4d45-a322-63c4cae1bb39/ this link but got nothing out of it.
Is there any idea related to implementing this functionality?

You need to handle grid's KeyDown event:
private void gvTradeFile_KeyDown(object sender, KeyEventArgs e)
{
if (e.KeyCode == Keys.Enter)
{
var row = dataGridView1.CurrentRow; // retreive the current row
// show the form
// ...
}
}
The Enter event occurs when keyboard focus enters into the grid, and RowEnter event occurs when a row receives input focus. These events have no relation to the Enter key.

Preventing double events in DataGridView

I have a problem that I am not sure how to solve. I have a DataGridView (EditMode = EditProgrammatically). This grid has one checkbox column and one or more textbox columns. The functionality is as following (or should be at least):
When you click on a checkbox, the checkbox should be toggled
When a row (or many rows) are selected, and you press space, the checkboxes should be toggled.
I have these two event handlers:
private void grid_CellClick(object sender, DataGridViewCellEventArgs e)
{
if (e.RowIndex >= 0 && e.ColumnIndex == useColumn.Index)
{
if (ModifierKeys != Keys.Shift && ModifierKeys != Keys.Control)
{
ToggleRows(grid.SelectedRows);
}
}
}
private void RowSelectorForm_KeyDown(object sender, KeyEventArgs e)
{
if (grid.Focused && e.KeyCode == Keys.Space)
{
ToggleRows(grid.SelectedRows);
e.Handled = true; // Not sure if this is needed or even does anything
e.SuppressKeyPress = true; // Or this for that matter...
}
}
This almost works. The problem is when you press space and a checkbox cell is active. When a textbox cell is active, it works like it should. The problem is that when you press space and a checkbox cell is active, both events gets fired. Which means it first selects and then deselects (or the reverse). So the checkboxes end up being like they was. How can I prevent this?
I have thought about using a flag, but not sure where I can put it, since I can't really know if it was a double event or if it was just the user using space and then clicking with the mouse. So that can't really be used I think. Is there a different event I should use? Is there a way to see if the cell was clicked by mouse or by space? Is there a way to disable the automatic checkbox toggling when space is pressed? What can I do?
Note: Reason for RowSelectorForm_KeyDown and not just grid_KeyDown was that I was trying to use KeyPreview and then suppress the keypress if it was space and the grid was focused. But that SuppressKeyPress doesn't really seem to do anything at all =/ Maybe I've just misunderstood it...

Well, I didn't want to do it, but I have now fixed it with a timer... but if anyone knows how to do it properly, please let me know!!
Current solution:
private DateTime lastClick = DateTime.MinValue;
and in both events:
if (DateTime.Now - lastClick > TimeSpan.FromMilliseconds(400))
{
lastClick = DateTime.Now;
ToggleRows(grid.SelectedRows);
}

It has been a time since I worked with C#, but I assume that you can disconnect the grid_CellClick event handler before calling ToggleGrid in RowSelectorForm_KeyDown.
After the call, you can reconnect the event handler.
Also, there might be some way to supress the event from being fired in the first place. In some API's certain methods are specially provided that don't trigger any events.

The frustrating problems are:
.Handled doesn't prevent the check box from changing
.SuppressKeyPress doesn't prevent the checkbox from changing
If you DoubleClick on the checkbox, the first click fires the Click() event (toggling the checkbox) and the second click fires the DoubleClick() event (toggling the checkbox yet again).
However, the KeyDown event fires before any of the grid events. Perhaps setting a flag to indicate the spacebar was pressed or if the row was already selected, reset the value of the checkbox.

I used the following and it seemed to work well:
private Keys _ClickSource = 0;
private void dgv_CellClick(object sender, System.Windows.Forms.DataGridViewCellEventArgs e)
{
if (_ClickSource == 0 || _ClickSource != Keys.Space)
{
dgv.Rows[e.RowIndex].Cells[e.ColumnIndex].Value = ! (System.Convert.ToBoolean(dgv.Rows[e.RowIndex].Cells[e.ColumnIndex].Value));
}
_ClickSource = null;
}
private void dgv_KeyDown(object sender, System.Windows.Forms.KeyEventArgs e)
{
_ClickSource = e.KeyCode;
}