private static TextParam getFunctionDisplayString(final FormulaFunction f) {
        //find the shortest abbrevation
        String fAbbr = f.getMainName();
        for (String name : f.getNames()) {
            if (name.length() < fAbbr.length()) {
                fAbbr = name;
            }
        }
        return TextParam.text(f.getUserDisplayableString() + " (" + fAbbr + ")");
    }
Shows a function selection dialog, and upon user selection pastes the function into the formula field given by 'formulaView'
main/src/main/java/cgeo/geocaching/utils/formulas/FormulaUtils.java