Show/Hide controls

[Madhavi Balusu]

Hi,
You probably answered this million times, but I don''t have the time to look around, so...

What is a good place(s) for me to Show/Hide my custom control in a grid? Right now I am doing it in Renderer''s OnDraw and that is giving me a lot of problems..

1) When the user "enters" the cell ( click/tab/Setting Focus in the code etc), I need to show the control with the right size ( cell''s size).

2) Conversely, commit and hide the above shown control when the user "leaves" the cell...

Short deadline, please advise.

[Administrator]

Hi Monica,
Renderer.OnDraw is the correct method to set the controls size / visibility. Try calling the base class only when the cell is in focus to see if that serves your purpose.

Here is the code I tried in the Windows\Grid.Windows\samples\CellTypes\CalendarCells sample.

protected override void OnDraw(Graphics g, Rectangle clientRectangle, int rowIndex, int colIndex, GridStyleInfo style)
{
clientRectangle.Size = GridUtil.Max(clientRectangle.Size, CalendarCellModel.CalendarControlSize);
if (this.ShouldDrawFocused(rowIndex, colIndex))
{
style.Control = editCalendar;
base.OnDraw (g, clientRectangle, rowIndex, colIndex, style);
}

Best regards,
Jay N

[Madhavi Balusu]

OnDraw is not working for me. It is a very busy call.

Would OnBeginEdit/OnEndEdit work?

[Administrator]

Hi Monica,
When the grid needs to calculate CellLayout in the OnDraw, it gets the clientrectangle from Renderer.OnLayout.
So you could try this, instead of setting the size in OnDraw, return the desired size by overriding OnLayout to see if that helps.

protected override Rectangle OnLayout(int rowIndex, int colIndex, GridStyleInfo style, Rectangle innerBounds, Rectangle[] buttonsBounds)
{
Rectangle r = base.OnLayout (rowIndex, colIndex, style, innerBounds, buttonsBounds);

 // Onlayout for other cells
if (!this.ShouldDrawFocused(rowIndex, colIndex))
  return new Rectangle(r.X, r.Y, 0, 0);
else
 //for CurrentCell
  return r;
}

Best regards,
Jay N

[Madhavi Balusu]

Thanks Jay. That is exactly what I am doing. So my control sizes fine, but what about init/commit my control from/to the grid? For this purpose would OnBeginEdit/OnEndEdit do?

There seem to be a lot of calls that could be used during committing the values *from* the customcontrol *to* the grid: OnSaveChanges/OnValidating/OnDeactivating etc..But the question is what is the "right" call to commit the values?

[Administrator]

Hi Monica,
Please try initializing your control in OnInitialize override and save the changes from control to the Grid in OnSaveChanges override.

protected override void OnInitialize(int rowIndex, int colIndex)
{

}

protected override bool OnSaveChanges()
{

}

Windows\Grid.Windows\samples\CellTypes\SliderCells is a good sample to see the implementation.

Best regards,
Jay N

[Madhavi Balusu]

Weird Behaviors:

My grid is wired to GridTextBoxCellRenderer. What does it mean when:

1) the Renderer''s OnInitialize is called with CurrentCell.IsEditing = true;? Should''nt it be false? This is happening with only 1 grid, other grids it is set to false.

2) For some reason in the renderer call, the current cell is getting unwired with the renderer, i.e. this.CurrentCell.Renderer = null; Looking at your code, I figured I had to do:
SetPositionNoActivate ( in Onlayout)
But the question is why did my currentcell''s renderer become null in the first place.

Thanks.

[Administrator]

Hi Monica,
Is it possible to post a sample showing the problem? It would help us to analyze the issue better.

Thanks,
Jay N

[Madhavi Balusu]

No, don''t have that kind of time.

I worked around the IsEditing problem using CancelEdit().
My only concern is if I am masking a bigger problem by these working around with above mentioned calls.