function[obj] = askForBaseline(obj)

bl_types = {'None',...
            'Average', ...
            'Min', ...
            'Lowest n% average', ...
            'Offset (fitted line)',...
            'Fixed point'};

np_types = [10 15 20 25 50];        
np_labels= {'10%',...
            '15%', ...
            '20%', ...
            '25%', ...
            '50%',...
            'Other'};
                                          
[s,OkClicked] = listdlg('PromptString','Select a baseline correction:',...
                      'SelectionMode','single',...
                      'ListString',bl_types, 'ListSize', [150 75]);
 
if OkClicked             
    if (s == 4)
        [s2,OkClicked] = listdlg('PromptString','Select a percentile:',...
                                'SelectionMode','single',...
                                'ListString',np_labels, 'ListSize', [150 75]);
        
        if (s2 == 6)
            wrong_answer =1;
            while wrong_answer
                line = inputdlg({'Other percentile :'}, 'Percentile', 1, {'25'});
                answer = str2num(line{1});
                wrong_answer = ~((answer > 0) && (answer < 100));
            end
            percentile = answer;
        else
            percentile = np_types(s2);
        end
        
        obj.settings.BaselineCorrection = [s-1 percentile];
    else
        obj.settings.BaselineCorrection = [s-1];
    end
end