How to change the alpha value of the first table in grouped table in iphone?

I am new to iphone development. I am displaying my content in grouped table view. I want to change the alpha value of the first group of my table only. How can 开发者_如何学Pythoni achieve that. Please help me out. Thanks.

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What do you mean with "first table"?

Changing the alpha value of a table is done by

table.alpha = new_value

where new_value ranges from 0 to 1.

Marco