通过调用 notifyDataSetChange 未在运行时更新可扩展列表视图适配器子答案

【问题标题】：The expandablelistview adapter child not updated on runtime by calling notifyDataSetChange通过调用 notifyDataSetChange 未在运行时更新可扩展列表视图适配器子
【发布时间】：2018-06-20 10:06:57
【问题描述】：

在组视图的 BaseExpandableListAdapter 上有一个按钮，用于在其子项中添加 cmets。将项目添加到列表并在该适配器类中调用 notifyDataSetChanged() 时，它不会立即更改，而是在折叠和展开列表后更改。

  private List<String> ParentItem;

  private LinkedHashMap<String, List<JsonCase>> ChildItem;

  public View getChildView(final int listPosition, final int expandedListPosition,boolean isLastChild, View convertView, final ViewGroup parent) {
    final JsonCase expandedListText = (JsonCase) getChild(listPosition, expandedListPosition);
    if (convertView == null) {
        LayoutInflater layoutInflater = (LayoutInflater) this.context
                .getSystemService(Context.LAYOUT_INFLATER_SERVICE);

            convertView = layoutInflater.inflate(R.layout.hearing_detail,parent, false);

    }

        final EditText comment = (EditText) convertView.findViewById(R.id.comment);
        TextView commentorName = (TextView) convertView.findViewById(R.id.commentorName);
        TextView commentDate = (TextView) convertView.findViewById(R.id.commentDate);
        comment.setText("" + expandedListText.details);
        if(expandedListText.commentorName!=null &&expandedListText.commentorName.equals("")){
            commentorName.setEnabled(false);
        }else{
            commentorName.setText(expandedListText.commentorName);
        }

        commentDate.setText(expandedListText.date);

    return convertView;
}

public void addCaseHearingsToAdapter(int listPosition){

    String hearingId = this.ChildItem.get(this.ParentItem.get(listPosition)).get(0).hearingId;
    String userId = PreferenceData.getLoggedInUserId(context);
    JsonCase comment = new JsonCase();
    comment.commentId = "";
    comment.hearingId = hearingId;
    comment.commentedBy = userId;
    comment.details = "";
    comment.commentorName = "";
    comment.date =  new SimpleDateFormat("dd MMMM yyyy hh:mm:ss").format(Calendar.getInstance().getTime());

    this.ChildItem.get(this.ParentItem.get(listPosition)).add(comment);
    this.notifyDataSetChanged();

}

点击添加评论按钮子后未更新：

再次折叠和展开后子更新：

【问题讨论】：

标签： java android expandablelistview expandablelistadapter notifydatasetchanged

【解决方案1】：

你可以尝试刷新适配器吗

getActivity().runOnUiThread(new Runnable() {
    public void run() {
        this.notifyDataSetChanged();
    }
});

【讨论】：

它在 addCaseHearingsToAdapter 函数中的位置吗？
addCaseHearingsToAdapter() 函数在 expandableAdapterClass 中，所以这个 getActivity() 函数在这个可扩展适配器类中没有解析
我正在这样做 new Handler().post(new Runnable() { public void run() { notifyDataSetChanged(); } });但它不再工作了
我也检查了这个链接但是stackoverflow.com/questions/6374378/…但是什么也没找到

【解决方案2】：

实际上，在我的情况下，expandableListView 的高度没有更新，因此会导致运行时出现问题。在深入研究代码之后。我在 notifyDataSetChanged() 之后调用这个 setListViewHeight 函数，使我的消耗性列表视图在运行时更新。我将 expandablelistView 的高度设置为：

   public static void setListViewHeight(ExpandableListView listView, int group) {
    ExpandableListAdapter listAdapter = (ExpandableListAdapter) listView.getExpandableListAdapter();
    int totalHeight = 0;
    int desiredWidth = View.MeasureSpec.makeMeasureSpec(listView.getWidth(),
            View.MeasureSpec.EXACTLY);
    for (int i = 0; i < listAdapter.getGroupCount(); i++) {
        View groupItem = listAdapter.getGroupView(i, false, null, listView);
        groupItem.measure(desiredWidth, View.MeasureSpec.UNSPECIFIED);

        totalHeight += groupItem.getMeasuredHeight();

        if (((listView.isGroupExpanded(i)) && (i != group)) || ((!listView.isGroupExpanded(i)) && (i == group))) {
            for (int j = 0; j < listAdapter.getChildrenCount(i); j++) {
                View listItem = listAdapter.getChildView(i, j, false, null,
                        listView);
                listItem.measure(desiredWidth, View.MeasureSpec.UNSPECIFIED);

                totalHeight += listItem.getMeasuredHeight()+1;

            }
        }
    }

    ViewGroup.LayoutParams params = listView.getLayoutParams();
    int height = totalHeight
            + (listView.getDividerHeight() * (listAdapter.getGroupCount() - 1));
    if (height < 10)
        height = 200;
    params.height = height;
    listView.setLayoutParams(params);
    listView.requestLayout();

}

【讨论】：