filtering chart on higher hierarchy node only

Hi,

I have a crosstab that is based on hierarchy and when I select a specific line, I want the chart to display data for this line. To achieve this, I simply use this line of code :

DS_CHART.setFilter("0MATERIAL", CROSSTAB_2.getSelectedMember("0MATERIAL"));

This is working fine as long as I'm displaying the lowest level of the hierarchy.

For instance, if my table contains something like

Frozen Food

     Vanilla Ice cream

      Chocolate Ice cream

When I click on Vanilla ice cream, the chart is displayed with one line for the Vanilla ice cream  data, I'm happy.

When I click on Frozen food, a line is displayed for frozen food but 2 other lines are displayed as well for Vanilla / Chocolate ice cream.

I would like to display ONLY the frozen food line.

Is there a way to do this ?

Thanks,

Dany