panzoombar=new SuperMap.Control.PanZoomBar();
panzoombar.forceFixedZoomLevel=true;
panzoombar.showSlider=true;
panzoombar.slideRatio=0.5;
panzoombar.sliderBarHeight=180;
panzoombar.sliderBarWidth=17;
panzoombar.levelsDesc = {levels:[ ???? ],imageSources:[ ???? ]};
map.addControl(panzoombar);
问号具体怎么写