Binding data to the custom DataGridView

All,
I have a customized DataGridView where I have implemented extra functionality and bounded datasource in the same custom DataGridView (Using
C# and .NET). Now, I could able to use it properly by placing it on a panel control. I have added label as button on panel control to display
data from datasource on to datagrid and create a binding source. Another Label which act as a button is used to update data from grid to
databse.
Issue: I pressed show label to display data in a dsatagridview. Modified the grid cell value and immediately pressed update label which is on
same panel control. I observed that, the cursor is still in the grid cell when I press Save button. While saving, the cell value is null even
though I have entered something in the presentation layer. My expected behaviour is to get the modified value while saving.
 Special Case: After typing something in the grid cell, if I click on somewhere else like the row below where I entered something, before I
click on Save button, it is working fine. (Here, mainly I tried to remove the focus from the currently modified cell)
Is there any way to bind sources before I click on save button? Please suggest me.
Please feel free to ask me if you need any information.
I have also seen same kind of problem on this forum, but unfortunately the author got the answer and didnt post it back.
here is that URL:
http://social.msdn.microsoft.com/Forums/en/winformsdesigner/thread/54dcc87a-adc2-4965-b306-9aa9e79c2946
Please help me.