How to set selected item of Spinner by value, not by position?

I have a update view, where I need to preselect the value stored in database for a Spinner.

I was having in mind something like this, but the Adapter has no indexOf method, so I am stuck.

void setSpinner(String value)
{
    int pos = getSpinnerField().getAdapter().indexOf(value);
    getSpinnerField().setSelection(pos);
}