怎么得到listview的item的view

for(int i=0;i<mHomeworkFeedbackRangeListView.getChildCount();i++){    LinearLayout item= (LinearLayout) mHomeworkFeedbackRangeListView.getChildAt(i);    TextView tv = (TextView) item.findViewById(R.id.text_homework_feedback_range_item);    tv.setText("0");}