using total row count in title band "Print When Expression"

[syalman]

hi to all
i have several "Detail" bar. And there is a table in each "Detail" band which gets data from own "Data Source". When report runs (all have own datasource ) returns total row count to the master dataset.

l want that "total row count" value to use in title band

i fixed a "Text Field"  to that Title Band. 

and i have set "Print When Expression" of that "Text Field" 

$V{v_row_count_main} !=null  

Yes my plan is total row count will be shown when table which is in "Detail" band returns rows.

i mean more than zero row. such as 1, 2, 3 or more row.

but when table returns zero row or null value that "Text Field" will be disappear..

but this is not working because "Print When Expression" always using $V{v_row_count_main} value in calculating as null.

thanks to all

[syalman]

yes i am expecting any answer