首先,ListView不能直接用,要自定义一个,然后重写onMeasure()方法:
public class ExpandableListView extends ListView {
public ExpandableListView(Context context) {
super(context);
}
public ExpandableListView(Context context, AttributeSet attrs) {
super(context, attrs);
}
public ExpandableListView(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
}
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
int expandSpec = MeasureSpec.makeMeasureSpec(Integer.MAX_VALUE >> 2,
MeasureSpec.AT_MOST);
super.onMeasure(widthMeasureSpec, expandSpec);
}
}
第二步:写个计算listView每个Item的方法:
public static void setListViewHeightBasedOnChildren(ListView listView) {
ListAdapter adapter = listView.getAdapter();
if (adapter == null) {
return;
}
int totalHeight = 0;
for (int i = 0, len = adapter.getCount(); i < len; i++) { //listAdapter.getCount()返回数据项的数目
View listItem = adapter.getView(i, null, listView);
listItem.measure(0, 0); //计算子项View 的宽高
totalHeight += listItem.getMeasuredHeight(); //统计所有子项的总高度
}
ViewGroup.LayoutParams params = listView.getLayoutParams();
params.height = totalHeight + (listView.getDividerHeight() * (adapter.getCount() - 1));
//listView.getDividerHeight()获取子项间分隔符占用的高度
//params.height最后得到整个ListView完整显示需要的高度
listView.setLayoutParams(params);
}
第三步:listview添加适配器后设置高度即可:
listView.setAdapter(adapter);
new ListViewUtil().setListViewHeightBasedOnChildren(listView);