Tabs communication

[therealjag]

hey there, i have created 4 tabs in my program but they dont seem to communicate with each other by this i mean like i have this method in my third tab:

int DesignTab::tariffReturn()
{
	return tariff1->currentIndex();
}

int DesignTab::tariffReturn()
{
	return tariff1->currentIndex();
}

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but when i try calling it from my 4th tab using DesignTab.tariffReturn( ) it gives an error when compiling saying the following:

"expected primary expression before '.' token"

does anyone know how i can call this method? or pass the value into my last tab?