怎样动态设置GridView的宽和高（Android）

1 LinearLayout.LayoutParams linearParams2 = (LinearLayout.LayoutParams)liveGrid.getLayoutParams();
2         linearParams2.width=(shipin_Adapter.getCount())*(cWidth+hSpacing);
3         linearParams2.height=cHight;
4         liveGrid.setLayoutParams(linearParams2);