AutoCompleteTextView 自定義篩選結果被忽略

Question

我為 AutoCompleteTextView 創建了一個自定義適配器。

package ...

import ...

public class CardSuggestionAdapter extends ArrayAdapter<String> implements Filterable {

    private final LayoutInflater mInflater;
    private Activity context;
    private int mFieldId, mResource;

    CardSuggestionAdapter(Activity context, String[] names) {
        super(context, R.layout.card_suggestion, R.id.name_label, names);
        this.context = context;
        this.mFieldId = R.id.name_label;
        this.mResource = R.layout.card_suggestion;
        this.mInflater = LayoutInflater.from(context);
    }

    @NonNull
    @Override
    public View getView(int position, @Nullable View convertView, @NonNull ViewGroup parent) {
        return createViewFromResource(mInflater, position, convertView, parent, mResource);
    }

    @NonNull
    @Override
    public Filter getFilter() {
        return new CardsFilter();
    }

    private View createViewFromResource(@NonNull LayoutInflater inflater, int position, @Nullable
            View convertView, @NonNull ViewGroup parent, int resource) {
        View view = convertView;
        final TextView text;

        ViewHolder viewHolder;
        if (convertView == null) {
            view = inflater.inflate(resource, parent, false);
            viewHolder = new ViewHolder(view);
            view.setTag(viewHolder);
        } else {
            viewHolder = (ViewHolder) view.getTag();
        }
        text = view.findViewById(mFieldId);
        if (text == null) {
            throw new RuntimeException("Failed to find view with ID "
                    + context.getResources().getResourceName(mFieldId)
                    + " in item layout");
        }

        final String item = getItem(position);
        viewHolder.name.setText(item);
        viewHolder.name.setTypeface(Typeface.createFromAsset(
                MarsPDA.assetManager, "fonts/prototype.ttf"));

        return view;
    }

    class ViewHolder {

        TextView name;

        ViewHolder(View v) {
            name = v.findViewById(R.id.name_label);
        }
    }

    private class CardsFilter extends Filter {

        @Override
        protected FilterResults performFiltering(CharSequence constraint) {
            if (constraint != null) {
                final List<String> suggestions = new ArrayList<>();
                final FilterResults fs = new FilterResults();
                return fs;
            } else {
                return new FilterResults();
            }
        }

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

performFiltering這種實現顯然使得不顯示任何建議。

我嘗試從原始ArrayAdapter類中復制performFiltering方法，並查看在此論壇上找到的其他一些Filter實現，但即使我實際上將任何內容添加到suggestions列表並設置fs.values = suggestions; 和fs.count = suggestions.size(); ，適配器顯示傳遞給構造函數的names數組的所有成員。 為什么會這樣？

Answer 1

我認為問題出在管理列表中，您可以嘗試以下更改聲明原始列表和過濾器，然后在構造函數中對其進行初始化。

覆蓋 get count 方法。

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

在過濾器類中進行如下更改：

private class CardsFilter extends Filter {

        @Override
        protected FilterResults performFiltering(CharSequence constraint) {

            FilterResults results = new FilterResults();        // Holds the results of a filtering operation in values
            List<String> FilteredArrList = new ArrayList<String>();
            if (constraint == null || constraint.length() == 0) {

                // set the Original result to return
                results.count = namesOriginal.size();
                results.values = namesOriginal;
            } else {
                constraint = constraint.toString().toLowerCase();
                for (int i = 0; i < namesOriginal.size(); i++) {
                    String data = namesOriginal.get(i);
                    if (data.toLowerCase().startsWith(constraint.toString())) {
                        FilteredArrList.add(data);
                    }
                }
                // set the Filtered result to return
                results.count = FilteredArrList.size();
                results.values = FilteredArrList;
            }
            return results;

        }

        @Override
        protected void publishResults(CharSequence constraint, FilterResults results) {
            if (results != null && results.count > 0) {
                names= (ArrayList<String>) results.values;
                notifyDataSetChanged();
            } else {
                names.addAll(namesOriginal);
                notifyDataSetInvalidated();
            }
        }
    }

希望這會有所幫助。