android - 如果在底部，ExpandableListView 不会滚动

Question

我有一个带有 Activity 的 Android 应用，里面有一个 ExpanableListView。

我想要的是 ExpandableListView 在我点击它时滚动所选组的标题，如果它不能(因为没有足够的垂直空间)，我想要它滚动到底部。

如果我在 ListView 底部有更多空间(即其他组)时点击一个组，则一切正常，并且 ListView 滚动以显示子项。(编辑:不，它没有；它只在第一次点击时正常工作，所有连续的尝试都不会导致滚动)

但是，如果 ListView 没有空间，则不会发生滚动，组会展开，然后我可以进一步向下滚动以查看子组。

我尝试了很多方法，例如覆盖“onGroupClick”和调用“smoothScrollToPosition”，但结果几乎相同。

任何帮助将不胜感激。

Answer 1

您可以尝试类似下面的操作。完美运行:

public static class LineupFragment extends Fragment {

View rootView;
ExpandableListView lv;
private String[] groups;
private String[][] children;


public LineupFragment() {

}

public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    groups = new String[] { "Test Header 1", "Test Header 2", "Test Header 3", "Test Header 4" };

    children = new String [][] {
        { "s simply dummy text of the printing and typesetting industry. Lorem Ipsum has been the industry's standard dummy text ever since the 1500s, when an unknown printer took a galley of type and scrambled it to make a type specimen book. It has survived not only five centuries, but also the leap into electronic typesetting, remaining essentially unchanged. It was popularised in the 1960s with the release of Letraset sheets containing Lorem Ipsum passages, and more recently with desktop publishing software like Aldus PageMaker including versions of Lorem Ipsum." },
        { "Contrary to popular belief, Lorem Ipsum is not simply random text. It has roots in a piece of classical Latin literature from 45 BC, making it over 2000 years old. Richard McClintock, a Latin professor at Hampden-Sydney College in Virginia, looked up one of the more obscure Latin words, consectetur, from a Lorem Ipsum passage, and going through the cites of the word in classical literature, discovered the undoubtable source. Lorem Ipsum comes from sections 1.10.32 and 1.10.33 of comes from a line in section 1.10.32." },
        { "It is a long established fact that a reader will be distracted by the readable content of a page when looking at its layout. The point of using Lorem Ipsum is that it has a more-or-less normal distribution of letters, as opposed to using 'Content here, content here', making it look like readable English. Many desktop publishing packages and web page editors now use Lorem Ipsum as their default model text, and a search for 'lorem ipsum' will uncover many web sites still in their infancy. Various versions have evolved over the years, sometimes by accident, sometimes on purpose (injected humour and the like)." },
        { "There are many variations of passages of Lorem Ipsum available, but the majority have suffered alteration in some form, by injected humour, or randomised words which don't look even slightly believable. If you are going to use a passage of Lorem Ipsum, you need to be sure there isn't anything embarrassing hidden in the middle of text. All the Lorem Ipsum generators on the Internet tend to repeat predefined chunks as necessary, making this the first true generator on the Internet. It uses a dictionary of over 200 Latin words, combined with a handful of model sentence structures, to generate Lorem Ipsum which looks reasonable. The generated Lorem Ipsum is therefore always free from repetition, injected humour, or non-characteristic words etc." }
    };
}

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    rootView = inflater.inflate(R.layout.fragment_lineup, container, false);  

return rootView;
}

@Override
public void onViewCreated(View view, Bundle savedInstanceState) {
    super.onViewCreated(view, savedInstanceState);

    lv = (ExpandableListView) view.findViewById(R.id.expListView);
    lv.setAdapter(new ExpandableListAdapter(groups, children));
    lv.setGroupIndicator(null);

}

public class ExpandableListAdapter extends BaseExpandableListAdapter {

    private final LayoutInflater inf;
    private String[] groups;
    private String[][] children;

    public ExpandableListAdapter(String[] groups, String[][] children) {
        this.groups = groups;
        this.children = children;
        inf = LayoutInflater.from(getActivity());
    }

    @Override
    public int getGroupCount() {
        return groups.length;
    }

    @Override
    public int getChildrenCount(int groupPosition) {
        return children[groupPosition].length;
    }

    @Override
    public Object getGroup(int groupPosition) {
        return groups[groupPosition];
    }

    @Override
    public Object getChild(int groupPosition, int childPosition) {
        return children[groupPosition][childPosition];
    }

    @Override
    public long getGroupId(int groupPosition) {
        return groupPosition;
    }

    @Override
    public long getChildId(int groupPosition, int childPosition) {
        return childPosition;
    }

    @Override
    public boolean hasStableIds() {
        return true;
    }

    @Override
    public View getChildView(int groupPosition, final int childPosition, boolean isLastChild, View convertView, ViewGroup parent) {

         ViewHolder holder;
            if (convertView == null) {
                convertView = inf.inflate(R.layout.list_item, parent, false);
                holder = new ViewHolder();

                holder.text = (TextView) convertView.findViewById(R.id.lblListItem);
                convertView.setTag(holder);
            } else {
                holder = (ViewHolder) convertView.getTag();
            }

            holder.text.setText(getChild(groupPosition, childPosition).toString());

            return convertView;
    }

    @Override
    public View getGroupView(int groupPosition, boolean isExpanded, View convertView, ViewGroup parent) {
        ViewHolder holder;

        if (convertView == null) {
            convertView = inf.inflate(R.layout.list_group, parent, false);

            holder = new ViewHolder();
            holder.text = (TextView) convertView.findViewById(R.id.lblListHeader);
            convertView.setTag(holder);
        } else {
            holder = (ViewHolder) convertView.getTag();
        }

        holder.text.setText(getGroup(groupPosition).toString());

        return convertView;
    }

    @Override
    public boolean isChildSelectable(int groupPosition, int childPosition) {
        return true;
    }

    private class ViewHolder {
        TextView text;
    }
}