2

我一直在实现自定义列表适配器和自定义过滤器。我已经到了可以通过键入过滤掉我的列表的地步，但是当我删除我的约束时，列表不会重新填充。我已经使用这两个来源来了解我的位置。http://www.google.com/codesearch/p?hl=it#uX1GffpyOZk/core/java/android/widget/ArrayAdapter.java&q=android%20arrayadapter&sa=N&cd=1&ct=rc

和使用 ArrayAdapter 在 Android 中进行自定义过滤

我迷失了下一步该做什么。这是我的代码：

private class stationAdapter extends ArrayAdapter<Station>
{

    //======================================
    public ArrayList<Station> stations;
    public ArrayList<Station> filtered;
    private Filter filter;
    //=====================

    public stationAdapter(Context context, int textViewResourceId, ArrayList<Station> stations)
    {
        super(context, textViewResourceId, stations);
        this.filtered = stations;
        this.stations = filtered;
        this.filter = new StationFilter();
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent)
    {
        View v = convertView;
        if (v == null)
        {
            LayoutInflater vi = (LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            v = vi.inflate(R.layout.row, null);
        }
        Station temp = stations.get(position);

        if (temp != null)
        {
            TextView stationName = (TextView) v.findViewById(R.id.stationname);
            TextView serviced = (TextView) v.findViewById(R.id.inservice);

            try
            {
                if (temp.isRedLine())
                {
                    // v.setBackgroundResource(R.color.red);
                    ImageView imageView = (ImageView) v.findViewById(R.id.icon);
                    imageView.setImageResource(R.drawable.redstation);
                    v.setBackgroundResource(temp.getAreaColour());
                }
                else
                {
                    ImageView imageView = (ImageView) v.findViewById(R.id.icon);
                    imageView.setImageResource(R.drawable.greenstation);

                    v.setBackgroundResource(temp.getAreaColour());
                }
            }
            catch (Exception e)
            {
                Log.d(TAG, "Null pointer");
            }
            if (stationName != null)
            {
                stationName.setText(temp.getName());
            }
            if (serviced != null)
            {
                serviced.setText(temp.getIrishName());
            }
        }
        return v;
    }

    //=====================================

    @Override
    public Filter getFilter()
    {
        if(filter == null)
            filter = new StationFilter();
        return filter;
    }

    private class StationFilter extends Filter
    {

        @Override
        protected FilterResults performFiltering(CharSequence constraint) {
            // NOTE: this function is *always* called from a background thread, and
            // not the UI thread.
            constraint = constraint.toString().toLowerCase();
            FilterResults result = new FilterResults();

            if(constraint != null && constraint.toString().length() > 0)
            {
                ArrayList<Station> filt = new ArrayList<Station>();
                ArrayList<Station> lItems = new ArrayList<Station>();
                synchronized (this)
                {
                    lItems.addAll(stations);
                }
                for(int i = 0, l = lItems.size(); i < l; i++)
                {
                    Station m = lItems.get(i);
                    if(m.getName().toLowerCase().startsWith((String) constraint))
                    {
                        filt.add(m);
                    }
                }
                result.count = filt.size();
                result.values = filt;
            }
            else
            {
                synchronized(this)
                {
                    result.values = stations;
                    result.count = stations.size();
                }
            }
            return result;
        }

        @SuppressWarnings("unchecked")
        @Override
        protected void publishResults(CharSequence constraint, FilterResults results) {
            // NOTE: this function is *always* called from the UI thread.
            filtered = (ArrayList<Station>)results.values;
            notifyDataSetChanged();
            clear();
            for(int i = 0, l = filtered.size(); i < l; i++){
                add(filtered.get(i));
            }
            notifyDataSetInvalidated();
        }

    }
    //===================================================

}

我是否需要从 Filterable 覆盖更多方法，或者我需要对我的视图做些什么？

任何帮助将不胜感激，谢谢。

4

2 回答 2

2 
        protected void cloneItems(ArrayList<Station> items) {
        for (Iterator<Station> iterator = items.iterator(); iterator
        .hasNext();) {
            Station s = (Station) iterator.next();
            originalItems.add(s);
        }
    }

这是过滤器工作的关键。使用传入的列表在构造函数中调用 clone 并且过滤器工作。

归功于这篇文章中的第一个答案：How to write a custom filter for ListView with ArrayAdapter

于 2011-06-28T13:57:14.270 回答
0

基本上你应该在所有更改之后调用 notifyDataSetChanged。而您正在调用无效。这个线程似乎有很好的解释。Android ListView 适配器 notifyDataSetInvalidated() 与 notifyDataSetChanged()

另外，我认为您不需要 notifyDataSetChanged before clear。

于 2011-06-23T15:24:30.110 回答