listView arrayAdapter 错误

Question

我在尝试将我的 arrayAdapter 的构造函数用于 listView 时遇到错误。当我这样称呼它时：

ListArrayAdapter adapters = new ListArrayAdapter(this, R.layout.list_view_row_item,     foodList);

我得到错误（在 Eclipse 中）：

the constructor ListArrayAdapter(Context, int, ArrayList<ListItem>) is undefined.

这是arrayAdapter的代码：

import java.util.ArrayList;
import java.util.Calendar;
import java.util.Date;

import android.app.Activity;
import android.app.LauncherActivity.ListItem;
import android.content.Context;
import android.os.Handler;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.ProgressBar;
import android.widget.TextView;


public class ListArrayAdapter extends ArrayAdapter<ListItem> {

Context mContext;
int layoutResourceId;
ListItem data[] = null;
private ProgressBar progressBar;
private int progressStatus = 0;
private TextView textView;
private Handler handler = new Handler();
ArrayList<ListItem> foodList = new ArrayList<ListItem>();


public ListArrayAdapter(Context mContext, int layoutResourceId, ArrayList<ListItem> foodList) {

    super(mContext, layoutResourceId, foodList);

    this.layoutResourceId = layoutResourceId;
    this.mContext = mContext;
    this.foodList = foodList;
}



@Override
public View getView(int position, View convertView, ViewGroup parent) {


    if(convertView==null){
        // inflate the layout
        LayoutInflater inflater = ((Activity) mContext).getLayoutInflater();
        convertView = inflater.inflate(layoutResourceId, parent, false);
    }           



    return convertView;

}

我的程序的主要部分：

import java.util.ArrayList;
import java.util.Calendar;
import java.util.Date;

import android.app.Activity;
import android.app.Fragment;
import android.content.Context;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.ListView;
import android.widget.Toast;

import com.app.fridgelist.*;


public class MainScreen extends Activity {

    private static Calendar d = Calendar.getInstance();
    private static Date kurrentTime = d.getTime();

    public int listItems;

    public static Context mainScreen;

    public ArrayList<ListItem> foodList = new ArrayList<ListItem>(); 
    private static ListItem newFood1 = new ListItem(0, "Pasta", 99, (int) (kurrentTime.getTime()));


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main_screen);

        if (savedInstanceState == null) {
            //getFragmentManager().beginTransaction()
                    //.add(R.id.container, new PlaceholderFragment())
                    //.commit();
        }

        mainScreen = this;


        foodList.add(newFood1);

        listItems = 1;

        ListArrayAdapter adapters = new ListArrayAdapter(getBaseContext(), R.layout.list_view_row_item, foodList);

        ListView yourListView = (ListView) findViewById(R.id.listOne);

        //yourListView.setAdapter(adapters);

        //yourListView.setOnItemClickListener(new OnItemClickListener() {


    }


    @Override
    public boolean onCreateOptionsMenu(Menu menu) {

        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main_screen, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();
        if (id == R.id.action_settings) {
            return true;
        }
        return super.onOptionsItemSelected(item);
    }

    /**
     * A placeholder fragment containing a simple view.
     */
    public static class PlaceholderFragment extends Fragment {

        public PlaceholderFragment() {
        }

        @Override
        public View onCreateView(LayoutInflater inflater, ViewGroup container,
                Bundle savedInstanceState) {
            View rootView = inflater.inflate(R.layout.fragment_main_screen, container, false);
            return rootView;
        }
    }

}

Answer 1

// try this way,hope this will help you...

activity_main.xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent" >

    <ListView
        android:id="@+id/lstFood"
        android:layout_width="match_parent"
        android:layout_height="match_parent"/>
</LinearLayout>

list_item.xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:padding="5dp">

    <TextView
        android:id="@+id/txtFood"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textSize="20sp"/>

</LinearLayout>

MainActivity.java
public class MainActivity extends Activity {

    private ListView lstFood;
    ArrayList<HashMap<String,String>> foodList;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        lstFood = (ListView) findViewById(R.id.lstFood);

        foodList = new ArrayList<HashMap<String, String>>();
        HashMap<String,String> food1 = new HashMap<String,String>();
        food1.put("id","1");
        food1.put("name","pasta");
        food1.put("prize","99");
        food1.put("time",String.valueOf(Calendar.getInstance().getTime()));

        HashMap<String,String> food2 = new HashMap<String,String>();
        food2.put("id","2");
        food2.put("name","pizza");
        food2.put("prize","199");
        food2.put("time",String.valueOf(Calendar.getInstance().getTime()));

        foodList.add(food1);
        foodList.add(food2);

        CustomAdapter adapters = new CustomAdapter(this,foodList);
        lstFood.setAdapter(adapters);
        lstFood.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
                HashMap<String,String> food = foodList.get(position);
                System.out.println("Food Id : "+food.get("id"));
                System.out.println("Food Name : "+food.get("name"));
                System.out.println("Food Prize : "+food.get("prize"));
                System.out.println("Food Time : "+food.get("time"));
            }
        });

    }



    class CustomAdapter extends BaseAdapter {

        private Context mContext;
        private ArrayList<HashMap<String,String>> foodList;

        public CustomAdapter(Context mContext,ArrayList<HashMap<String,String>> foodList) {
            this.mContext = mContext;
            this.foodList = foodList;
        }

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

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

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

        @Override
        public View getView(int position, View convertView, ViewGroup parent) {
            ViewHolder holder;
            if (convertView == null) {
                holder = new ViewHolder();
                convertView = LayoutInflater.from(mContext).inflate(R.layout.list_item, parent, false);
                holder.txtFood = (TextView) convertView.findViewById(R.id.txtFood);
                convertView.setTag(holder);
            }else{
                holder = (ViewHolder) convertView.getTag();
            }

            holder.txtFood.setText(foodList.get(position).get("name"));

            return convertView;

        }

        class ViewHolder{
            TextView txtFood;
        }
    }

}

Answer 2

从这里改变

ListArrayAdapter adapters = new ListArrayAdapter(getBaseContext(), R.layout.list_view_row_item, foodList);

到

ListArrayAdapter adapters = new ListArrayAdapter(YourActivityName.this, R.layout.list_view_row_item, foodList);
yourListView.setAdapter(adapters);