Question

我在操作栏中创建了一个搜索图标。我尝试使用Strings Array，效果很好。但是，当我试图从Web服务器获取数据时。搜索效果不佳。虽然我试图修复它。但是，它仍然无法奏效。这是我的班级：

public class MainActivity extends AppCompatActivity {

private String URL=
        "TTTTTTTTTT.php";
private String Contact_NAME[] ;

private JSONParser jsonParser = new JSONParser();
private ListView mListView;
private my_Adapter ContactViewAdapter;
private ArrayList<Contacts_ListView> ContactView;
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
     mListView = (ListView)findViewById(R.id.listViewCountry);

    new Get_Contacts().execute();

}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    MenuInflater inflater = getMenuInflater();
    inflater.inflate(R.menu.menu_search, menu);
    MenuItem item = menu.findItem(R.id.menuSearch);
    SearchView searchView = (SearchView)item.getActionView();

    searchView.setOnQueryTextListener(new SearchView.OnQueryTextListener() {
        @Override
        public boolean onQueryTextSubmit(String query) {
            return false;
        }

        @Override
        public boolean onQueryTextChange(String newText) {
            ContactViewAdapter.getFilter().filter(newText);

            return false;
        }
    });
    return super.onCreateOptionsMenu(menu);
}

这是我的AsyncTask。我在MainActivity中使用它作为私有类

private class Get_Contacts extends AsyncTask<Void, Void, Boolean>
{
    private ProgressDialog mProgressDialog;

    private JSONObject jsonObjectResult = null;
    private String error;
    private String THE_URL ;

    public Get_Contacts(){
        THE_URL = Contact_URL ;
        WITH_INPUT = false ;
    } ;
    @Override
    protected void onPreExecute()
    {
        super.onPreExecute();
        ContactView = new ArrayList<Contacts_ListView>();
    }
    @Override
    protected Boolean doInBackground(Void... params)
    {
        List<NameValuePair> pairs = new ArrayList<NameValuePair>();
            pairs = null;       
        jsonObjectResult = jsonParser.makeHttpRequest(THE_URL, pairs);

        if (jsonObjectResult == null)
        {
            error = "ERROR";
            return false;
        }

        try
        {
            if (jsonObjectResult.getInt("success") == 1)
            {
                JSONArray jsonArray = jsonObjectResult.getJSONArray("posts");
                saving_loop =  jsonArray.length() ;

                JSONObject news ;

                for (int i = 0; i < jsonArray.length(); i++)
                {
                    news = jsonArray.getJSONObject(i);
                    Contacts_ListView listviewcontacts  = new Contacts_ListView
                            (
                                    news.getString("Contact_Name")
                            );
                    ContactView.add(listviewcontacts);

                }
                return true;
            }
            else
                error = jsonObjectResult.getString("message");

        }
        catch (Exception ex)
        {

        }
        return false;
    }

    @Override
    protected void onPostExecute(Boolean aBoolean)
    {
        super.onPostExecute(aBoolean);
        if (aBoolean)
        {
            ContactViewAdapter = new Contacts_ListViewAdapter_No_Checkbox(MainActivity.this,
                    ContactView);
            mListView.setAdapter(ContactViewAdapter);
        }
        else
            Toast.makeText(MainActivity.this, error, Toast.LENGTH_LONG).show();
    }
 }

 }

该应用程序有效，并没有给我任何错误。当我尝试搜索时。它没有搜索

这是我的适配器

public class Contacts_ListViewAdapter_No_Checkbox extends BaseAdapter   {
private Context mContext;
private List<Contacts_ListView> mData;
private MyFilter filter ;
private ArrayList<Contacts_ListView> originalList ;


public Contacts_ListViewAdapter_No_Checkbox (Context mContext, ArrayList<Contacts_ListView> mData) {
    //super(mContext, R.layout.contacts_shape_nocheckbox, mData);
    this.mContext = mContext;
    this.mData = mData;

    this.originalList = new ArrayList<Contacts_ListView>();
    this.originalList.addAll(mData);
}

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

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

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


@Override
public View getView(final int position, View convertView, ViewGroup parent)
{
    if (convertView == null)
    {
        LayoutInflater mInflater = (LayoutInflater)
                mContext.getSystemService(Activity.LAYOUT_INFLATER_SERVICE);
        convertView = mInflater.inflate(R.layout.contacts_shape_nocheckbox, null);
    }

    TextView Contact_Name = (TextView) convertView.findViewById(R.id.Contact_Name_1);
    Contact_Name.setText(mData.get(position).getContactName());

    return convertView;
}

public Filter getFilter() {
    if (filter == null){
        filter  = new MyFilter();
    }
    return filter;
}
private class MyFilter extends Filter
{

    @Override
    protected FilterResults performFiltering(CharSequence constraint) {

        constraint = constraint.toString();
        FilterResults result = new FilterResults();
        if(constraint != null && constraint.toString().length() > 0)
        {
            ArrayList<Contacts_ListView> filteredItems = new ArrayList<Contacts_ListView>();

            for(int i = 0, l = originalList.size(); i < l; i++)
            {
                Contacts_ListView nameList = originalList.get(i);
                if(nameList.toString().contains(constraint))
                    filteredItems.add(nameList);
            }
            result.count = filteredItems.size();
            result.values = filteredItems;
        }
        else
        {
            synchronized(this)
            {
                result.values = originalList;
                result.count = originalList.size();
            }
        }
        return result;
    }

    @SuppressWarnings("unchecked")
    @Override
    protected void publishResults(CharSequence contraint, FilterResults results)  {
        mData = (ArrayList<Contacts_ListView>) results.values;
        if (results.count > 0) {
            notifyDataSetChanged();
        } else {
            notifyDataSetInvalidated();
        }
    }
}

}

Answer 1

过滤器无法正常工作，因为您使用的是自定义对象。如果将String或int值传递给数组适配器，则知道如何对其进行过滤。但是，如果你传递自定义对象默认过滤器实现不得不知道如何处理。使用自定义适配器而不是arrayadapter

您需要做什么

扩展了ArrayAdater的BaseAdapter

在适配器中制作自定义过滤器 3.返回过滤结果

Filter myFilter = new Filter() {
@Override
protected FilterResults performFiltering(CharSequence constraint) {
 FilterResults filterResults = new FilterResults();   
 ArrayList<Contacts_ListView> tempList=new ArrayList<Contacts_ListView>();
 //constraint is the result from text you want to filter against. 
 //objects is your data set you will filter from
 if(constraint != null && objects!=null) {
     int length=objects.size();
     int i=0;
        while(i<length){
            Contacts_ListView item=objects.get(i);
            //do whatever you wanna do here
            //adding result set output array     

            tempList.add(item);

            i++;
        }
        //following two lines is very important
        //as publish result can only take FilterResults objects
        filterResults.values = tempList;
        filterResults.count = tempList.size();
  }
  return filterResults;
  }

  @SuppressWarnings("unchecked")
  @Override
  protected void publishResults(CharSequence contraint, FilterResults results)  {
  objects = (ArrayList<Contacts_ListView>) results.values;
  if (results.count > 0) {
   notifyDataSetChanged();
  } else {
      notifyDataSetInvalidated();
  }  
  }
  };

覆盖方法

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

更新了您的代码更改为代码

Contacts_ListView nameList = originalList.get(i);
                if(nameList.getContactName().toString().contains(constraint))
                    filteredItems.add(nameList);

搜索操作栏无法使用AsyncTask类

1 个答案: