AutocompleteTextView 错误：IllegalStateException：适配器的内容已更改但 ListView 未收到通知

Question

在我的 AutocompleteTextView 上取消或快速键入时，我在此类中遇到 IllegalStateException 错误。我已经阅读了一些关于此的内容，但我无法解决这个问题。 任何人都可以更正我的代码吗？

感谢任何帮助！ （对不起我的英语不好）

这是完整的错误：

java.lang.IllegalStateException: The content of the adapter has changed but ListView did      not receive a notification. Make sure the content of your adapter is not modified from a background thread, but only from the UI thread. [in ListView(-1, class android.widget.ListPopupWindow$DropDownListView) with Adapter(class com.turkeys.planandgo.Activity.MapActivity$AutoComplete)]

这是我的课：

public class AutoComplete extends ArrayAdapter<String> implements Filterable {
    private static final String LOG_TAG = "carEgiri";

    private static final String PLACES_API_BASE = "https://maps.googleapis.com/maps/api/place";
    private static final String TYPE_AUTOCOMPLETE = "/autocomplete";
    private static final String OUT_JSON = "/json";

    private static final String API_KEY = "AIzaSyCDycjwe51YuMe7Sx8nHv9Z6C-kBGPEQ64";

    private ArrayList<String> resultList;

    private ArrayList<String> autocomplete(String input) {
            ArrayList<String> resultList = null;

            HttpURLConnection conn = null;
            StringBuilder jsonResults = new StringBuilder();
            try {
                StringBuilder sb = new StringBuilder(PLACES_API_BASE + TYPE_AUTOCOMPLETE + OUT_JSON);
                sb.append("?sensor=false&key=" + API_KEY);
                sb.append("&input=" + URLEncoder.encode(input, "utf8"));

                URL url = new URL(sb.toString());
                conn = (HttpURLConnection) url.openConnection();
                InputStreamReader in = new InputStreamReader(conn.getInputStream());
                Log.d("====", "Requesst send");
                // Load the results into a StringBuilder
                int read;
                char[] buff = new char[1024];
                while ((read = in.read(buff)) != -1) {
                    jsonResults.append(buff, 0, read);
                }
            } catch (MalformedURLException e) {
                Log.e(LOG_TAG, "Error processing Places API URL", e);
                return resultList;
            } catch (IOException e) {
                Log.e(LOG_TAG, "Error connecting to Places API", e);
                return resultList;
            } finally {
                if (conn != null) {
                    conn.disconnect();
                }
            }

            try {
                // Create a JSON object hierarchy from the results
                Log.d("JSON","Parsing resultant JSON :)");
                JSONObject jsonObj = new JSONObject(jsonResults.toString());
                JSONArray predsJsonArray = jsonObj.getJSONArray("predictions");

                // Extract the Place descriptions from the results
                resultList = new ArrayList<String>(predsJsonArray.length());
                Log.d("JSON","predsJsonArray has length " + predsJsonArray.length());
                for (int i = 0; i < predsJsonArray.length(); i++) {

                    resultList.add(predsJsonArray.getJSONObject(i).getString("description"));
                    Log.d("JSON",resultList.get(i));
                }
            } catch (JSONException e) {
                Log.e(LOG_TAG, "Cannot process JSON results", e);
            }

            return resultList;
        }

    public AutoComplete(Context context, int textViewResourceId) {
        super((Context) context, textViewResourceId);
    }

    @Override
    public int getCount() {
        if (resultList == null)
            return 0;
        return resultList.size();
    }

    @Override
    public String getItem(int index) {
        return resultList.get(index);
    }

    @Override
    public Filter getFilter() {
        Filter filter = new Filter() {
                @Override
                protected FilterResults performFiltering(CharSequence constraint) {
                    FilterResults filterResults = new FilterResults();
                    if (constraint != null) {
                        // Retrieve the autocomplete results.
                        resultList = autocomplete(constraint.toString());

                        // Assign the data to the FilterResults
                        filterResults.values = resultList;
                        filterResults.count = resultList.size();
                    }
                    return filterResults;
                }

                @Override
                protected void publishResults(CharSequence constraint,FilterResults results) {
                    if (results != null && results.count > 0) {
                        notifyDataSetChanged();
                    } else {
                        notifyDataSetInvalidated();
                    }
                }
        };
        return filter;
    }

}

Answer 1

请从performFiltering 方法中删除 resultList。 performFiltering 方法在后台线程中运行。 here信息更清晰！

Answer 2

我遇到了同样的问题，经过大量调试和研究后，我通过重写 notifyDataSetChanged() 并评估了建议列表的大小解决了我的问题。它可能会帮助某人。代码sn-p如下：

private int size = 0; 

@Override
public void notifyDataSetChanged() {
      size = suggestionList.size();
      super.notifyDataSetChanged();
}

并将 getCount() 中的大小返回为：

@Override
public int getCount() {

   return size; // Return the size of the suggestions list.
}

My Case(Application) 中的自定义过滤器如下：

private class CustomFilter extends Filter {
        @Override
        protected FilterResults performFiltering(CharSequence constraint) {
            suggestions.clear();
            FilterResults filterResults = new FilterResults();
            try {

                    if (originalList != null && constraint != null) { // Check if the Original List and Constraint aren't null.
                        try {
                            for (int i = 0; i < originalList.size(); i++) {
                                // if (originalList.get(i).toLowerCase().contains(constraint)) {
                                if (originalList.get(i).toLowerCase().contains(constraint.toString().toLowerCase())) {
                                    suggestionList.add(originalList.get(i)); // If TRUE add item in Suggestions.
                                }
                            }
                        } catch (Exception e) {
                            e.printStackTrace();
                        }
                    } else {
                        notifyDataSetChanged();
                    }

            } catch (Exception e) {
                e.printStackTrace();
            }
           // Create new Filter Results and return this to publishResults;
            filterResults.values = suggestionList;
            filterResults.count = suggestionList.size();

            return filterResults;
        }

        @Override
        protected void publishResults(CharSequence constraint, FilterResults results) {
           if (results != null && results.count > 0) {
                notifyDataSetChanged();
            } else {
                notifyDataSetInvalidated();
            }
        }
    }

Answer 3

遇到同样的问题 我做了一些改变来解决它： 1) 不要在 performFiltering(...) 方法中对数据集进行任何更改
2) 仅在 publishResults(...) 方法中进行更改

所以我们制作了类似的东西：

//suggestions dataset
ArrayList<Item> suggestions = new ArrayList<>();

在过滤器中

@Override
    protected void publishResults(CharSequence constraint, FilterResults results) {
       if (results != null && results.count > 0) {
            // rewrite array or clear it and fill new items in it
            suggestions = (ArrayList<Item>)results.values
            notifyDataSetChanged();
        }
    }

并且在 getCount() 方法中的适配器中返回建议大小：

@Override
public int getCount() {
    return suggestions.size();
}

Answer 4

在响应网络调用方法时添加 notifyDataSetChanged()