android - Achartengine graph displaying too much space between values -

i trying plot graph using achartengine. can see image, looks quite ugly.i want , 1. reduce space between values. cannot have space since need add more series it. 2. not plotting negative values, why it's showing lines @ bottom. values displayed @ bottom -1.i want eliminate lines @ bottom. 3. if possible, want change background color of graph black other color. thanks. code included working.

string see = pull.trim();            string str = '"' + see + '"';             int[] intarray = new int[str.length()];            for(int i=0; < str.length(); i++){                 intarray[i] = character.digit(str.charat(i), 10);             }           categoryseries series = new categoryseries("my graph");         for(int = 0; <intarray.length; i++){            series.add("bar ", intarray[i]);         }          xymultipleseriesdataset dataset = new xymultipleseriesdataset();         dataset.addseries(series.toxyseries());          xyseriesrenderer renderer = new xyseriesrenderer();         renderer.setdisplaychartvalues(true);         renderer.setchartvaluesspacing((float) 0.1);         renderer.setcolor(getresources().getcolor(r.color.fuchsia));            xymultipleseriesrenderer mrenderer = new xymultipleseriesrenderer();         mrenderer.addseriesrenderer(renderer);         mrenderer.setcharttitle("my graph");         mrenderer.setytitle("values");         mrenderer.setzoombuttonsvisible(true);             linearlayout chart_container=(linearlayout)findviewbyid(r.id.chart_layout);          mchart=(graphicalview)chartfactory.getbarchartview(getbasecontext(), dataset, mrenderer, type.default);         chart_container.addview(mchart); 

i found out bottom negative values showing because there spaces in string plotting graph.so wrote way, helps in future.

string see = pull.replaceall("\\s+","");     int[] intarray = new int[see.length()];            for(int k=0; k < see.length(); k++){                 intarray[k] = character.digit(see.charat(k), 10);             }