Question

我做了一个自动完成的简单演示，其中每个东西都运行良好。但是当我写第一个字符performFiltering（CharSequence约束）约束给出null值时有一个问题，但之后它给出了正确的值。例如，如果我写“p”它给出null。然后如果我写“pa”它给出约束“pa”..为什么它给第一次空值。其次如何获取自动完成列表的点击事件（我想获取所选项目的文本）这是我的代码..

public class CustomAutocompletAdapter extends BaseAdapter implements Filterable {

        private String stationNameAndCodeValue;
        ArrayList<String> autolistArray;
        ArrayList<String> objects;
        private Context context;

        public CustomAutocompletAdapter(Context context, String[] autolistArray) {
                this.autolistArray = new ArrayList<String>();
                for (int i = 0; i < autolistArray.length; i++) {
                        this.autolistArray.add(autolistArray[i]);

                }
                this.context = context;
        }

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

        @Override
        public Object getItem(int position) {
                return autolistArray.get(position);
        }

        @Override
        public long getItemId(int position) {
                return position;
        }

        @Override
        public View getView(int position, View convertView, ViewGroup parent) {
                View v = convertView;
                if (v == null) {
                        LayoutInflater mInflater = (LayoutInflater) context
                                        .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
                        v = mInflater.inflate(R.layout.custom_row_adapter, null);
                }

                final TextView stationNameAndCode = (TextView) v
                                .findViewById(R.id.item_selectStationName);

                stationNameAndCodeValue = autolistArray.get(position);

                stationNameAndCode.setText(stationNameAndCodeValue);

                return v;
        }

        Filter myFilter = new Filter() {

                @SuppressWarnings("unchecked")
                @Override
                protected void publishResults(CharSequence constraint,
                                FilterResults results) {

                        System.out.println("Constraint " + constraint);
                        Log.d("-----------", "publishResults");
                        if (results.count > 0 && results != null) {
                                autolistArray = (ArrayList<String>) results.values;
                                notifyDataSetChanged();
                        } else {
                                notifyDataSetInvalidated();
                        }

                }

                @Override
                protected FilterResults performFiltering(CharSequence constraint) {
                        Log.d("-----------", "performFiltering");
                        FilterResults results = new FilterResults();
                        List<String> filteredArrList = new ArrayList<String>();
                        if (objects == null) {
                                objects = new ArrayList<String>(autolistArray);
                        }
                        Locale locale = Locale.getDefault();
                        if (constraint == null || constraint.length() == 0) {
                                // set the Original result to return
                                results.count = objects.size();
                                results.values = objects;

                        } else {
                                constraint = (String) constraint.toString().toLowerCase(locale);
                                Pattern logEntry = Pattern.compile("-\\((.*?)\\)");
                                for (int i = 0; i < objects.size(); i++) {
                                        String name = objects.get(i);
                                        // System.out.println(name);

                                        Matcher matchPattern = logEntry.matcher(name);
                                        String subText = "";
                                        while (matchPattern.find()) {
                                                subText = matchPattern.group(1);
                                        }
                                        if (subText.toLowerCase(locale).contains(constraint)) {
                                                System.out
                                                                .println("CustomAutocompletAdapter.myFilter.new Filter() {...}.performFiltering()");
                                                filteredArrList.add(name);
                                        }
                                }
                                System.out.println(filteredArrList);
                                // set the Filtered result to return
                                results.count = filteredArrList.size();
                                results.values = filteredArrList;

                        }
                        return results;
                }

        };

        @Override
        public Filter getFilter() {
                return myFilter;
        }
}

主要活动：

protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.select_station);

         autocompleteView = (AutoCompleteTextView) findViewById(R.id.item_autoComplete);

         STATION_LIST = new String[GlobalList.stationList.length
                                            + GlobalExtendStationList.stationList.length];
                                    System.arraycopy(GlobalList.stationList, 0, STATION_LIST, 0,
                                            GlobalList.stationList.length);
                                    System.arraycopy(GlobalExtendStationList.stationList, 0,
                                            STATION_LIST, GlobalList.stationList.length,
                                            GlobalExtendStationList.stationList.length);
                                    autosuggestAdapter = new CustomAutocompletAdapter(this,STATION_LIST);
                                    autocompleteView.setAdapter(autosuggestAdapter);

有更新吗？

Answer 1

此行为是因为AutoCompleteTextView仅在字符数大于阈值时才执行过滤（请参阅source），并且您不能将此阈值分配给小于1.默认情况下，阈值为2.如果1个字符足够为你，致电

autocompleteView.setThreshold(1);

否则，您可以继承AutoCompleteTextView并覆盖setThreshold方法。

为什么第一次空值出现在自动完成中？

1 个答案: