iPhone implementation: ( the search bar is hidden by default ,if you scroll it ,it will display on the top)


If  you scroll down the screen , the top search bar will have a positive offset ,then it will enter the device screen so that the user will see it.

 



If you scroll up the screen ,then the top search bar will  have a negative offset ,then it will disappear again in the screen so that the use will not see it anymore.

 

In our project:

because when we search it and render the result page ,every search result includes not only text but also picture ,so every cell is very large .If search result has only 4 but by default one page has 6 cells ,then 6-4=2 cells must be empty .

We do not want the user to see the empty cells with border ,it may not have a good look-and-feel.

So we suggest that the empty cells without border ,so that it will be merged better with the background.