ALV gris control

Hi all,

I am using 2 subscreens. In the 1st subscreen I have place 1 field say customer num. in the 2nd subscreen I placed alv grid control.

step1: I entered customer number.

step 2: I placed cursor on the grid control and pressed enter button, in the debugging mode customer number is empty. Customer number what I enterd was not read.

Plz help