关于GridView的内容高度的问题

public View getView(final int position, View view, ViewGroup parent) {
if (view == null) {
view = getLayoutInflater().inflate(
R.layout.activity_tab_gviewpager_grid_item, null);
}
int pHight = mGridView.getHeight();
GridView.LayoutParams params = new GridView.LayoutParams(
LayoutParams.MATCH_PARENT, (pHight - 5) / 3);
view.setLayoutParams(params);