使用自定义ArrayAdapter进行过滤

时间:2011-04-20 10:48:56

标签: android listview filter android-arrayadapter

我一直在努力解决这个问题,尽管找了一会儿但找不到答案。我有一个自定义arrayAdapter,它使用自定义对象POI填充我的列表视图。

package com.WasserSportLotse;

import java.util.ArrayList;

import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.Filter;
import android.widget.ImageView;
import android.widget.TextView;

class poiAdapter extends ArrayAdapter<POI>{


    private ArrayList<POI> items;
    private Context mContext;
    public ArrayList<POI> allItems;
    private Filter filter;
    public ArrayList<POI> filtered;

    public poiAdapter(Context context, int textViewResourceId, ArrayList<POI> items){
        super(context, textViewResourceId, items);
        mContext = context;
        this.items = items;


}

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
            View v = convertView;
            if (v == null) {
                LayoutInflater vi = (LayoutInflater)mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
                v = vi.inflate(R.layout.list_items, null);
            }
            POI poi = items.get(position);
            if (poi != null) {
                    TextView mDistanceTextView = (TextView) v.findViewById(R.id.listitems_distancetxt);
                    TextView mNameTextView = (TextView) v.findViewById(R.id.listitems_nametxt);
                    TextView mCategoryTextView = (TextView) v.findViewById(R.id.listitems_categorytxt);
                    if (mDistanceTextView != null) {
                        mDistanceTextView.setText(poi.getDistance()+"km");                            
                        }
                    if(mNameTextView != null){
                        mNameTextView.setText(poi.getName());
                    }
                    if(mCategoryTextView != null){
                        mCategoryTextView.setText(poi.getType());
                        setImage(poi.getType(), v);

                    }
            }
            return v;
    }

    private void setImage(String type, View v) {
        if ("shopping".equals(type)){
            ImageView mImage = (ImageView) v.findViewById(R.id.imageView1);
            mImage.setImageResource(R.drawable.shopping);
        }
        if ("liegestelle".equals(type)){
            ImageView mImage = (ImageView) v.findViewById(R.id.imageView1);
            mImage.setImageResource(R.drawable.liegestelle);
        }
        if ("restaurant".equals(type)){
            ImageView mImage = (ImageView) v.findViewById(R.id.imageView1);
            mImage.setImageResource(R.drawable.restaurant);
        }
        if ("schleuse".equals(type)){
            ImageView mImage = (ImageView) v.findViewById(R.id.imageView1);
            mImage.setImageResource(R.drawable.schleuse);
        }
        if ("verein".equals(type)){
            ImageView mImage = (ImageView) v.findViewById(R.id.imageView1);
            mImage.setImageResource(R.drawable.verein);
        }
        if ("tankstelle".equals(type)){
            ImageView mImage = (ImageView) v.findViewById(R.id.imageView1);
            mImage.setImageResource(R.drawable.tankstelle);
        }
        if ("faekalien".equals(type)){
            ImageView mImage = (ImageView) v.findViewById(R.id.imageView1);
            mImage.setImageResource(R.drawable.faekalien);
        }
        if ("werkstatt".equals(type)){
            ImageView mImage = (ImageView) v.findViewById(R.id.imageView1);
            mImage.setImageResource(R.drawable.werkstatt);
        }
        if ("uebernachtung".equals(type)){
            ImageView mImage = (ImageView) v.findViewById(R.id.imageView1);
            mImage.setImageResource(R.drawable.uebernachtung);
        }

    }



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

    private class POITypeFilter 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<POI> filt = new ArrayList<POI>();
                ArrayList<POI> lItems = new ArrayList<POI>();
                synchronized (this)
                {
                    lItems.addAll(items);
                }
                for(int i = 0, l = lItems.size(); i < l; i++)
                {
                    POI m = lItems.get(i);
                    if(m.getType().toLowerCase().contains(constraint))
                        filt.add(m);
                }
                result.count = filt.size();
                result.values = filt;
            }
            else
            {
                synchronized(this)
                {
                    result.values = items;
                    result.count = items.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<POI>)results.values;
            notifyDataSetChanged();
            clear();
            for(int i = 0, l = filtered.size(); i < l; i++)
                add(filtered.get(i));
            notifyDataSetInvalidated();
        }

    }


}

我正在尝试覆盖getFilter方法,以便我可以通过POI.type过滤每个POI并更新listView。我这样调用getFilter

    @Override
protected void onRestart() {
    super.onRestart();
    mAdapter.getFilter().filter(getFilterSettings());
    mAdapter.notifyDataSetChanged();
}

这只会返回一个黑屏,好像所有内容都已被过滤掉一样。我在getFilter上添加了断点,但应用程序确实进入了它,因此我不确定应用程序是否正在使用此代码。有什么明显的东西我不见了吗?

更新 - 中途停留

我在这里遇到了一些问题。看起来应用程序没有调用getFilter作为不停在那里的断点。事实上,Davlik虚拟机只能使用这么多的断点(记住它并不是很多)。它正好在我使用我想要分析的代码的时候停止使用断点。我觉得我很不走运。

然后代码中出现了一些问题。我改变了

 private ArrayList<POI> items; 

公开。因此可以将其读入新数组并过滤结果。现在只是想弄清楚如何使arrayAdapter再次过滤,但是在原始数组上。哇,这是一个漫长的过程。

1 个答案:

答案 0 :(得分:2)

如果要创建自定义过滤器,您只需在POI类上创建一个toString()方法,该方法返回您要过滤的值。