popupwindow 无法按照坐标正确显示

[u010757798]

/**
* x_location, y_location 是相对于手机上的绝对坐标位置
*/
public void onClick(View v) {
//得到要显示的布局视图
View vw = getPopupWindows(index-1,0);
int width = DensityUtil.dip2px(context, 320);
int height = DensityUtil.dip2px(context, 160);
pw = new PopupWindow(vw, width, height);
if(pw!=null && !pw.isShowing()){
pw.showAtLocation(view, Gravity.NO_GRAVITY, x_location, y_location-160);
}
}