android - 如何创建仅包含某些可扩展项目的列表？

Question

我正在尝试编写一个列表，其中包含一些可扩展的项目和一些单个项目。我希望拥有它，以便在单击单个项目或可扩展列表子项时，我可以根据项目的文本调用 Intent 。

我想可扩展列表会起作用，但有没有办法在可扩展列表中设置项目，使它们没有可扩展列表图标？我应该使用字符串数组以外的东西吗？

执行此操作的最佳方法是什么？

谢谢

下面是我的不完整代码，我想在项目“Atlanta”和“Boston”之间或作为亚特兰大的子集插入项目“Zone 1”、“Zone 2”、“Zone 3”:

package test.lists.special;

import android.app.ListActivity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;

public class SpecialList extends ListActivity{
TextView toptext;
String[] items={"Atlanta", "Boston", "Chicago", "Dallas"};

@Override

 public void onCreate(Bundle icicle) {
  super.onCreate(icicle);
  setContentView(R.layout.main);
  setListAdapter(new ArrayAdapter<String>(this,
  android.R.layout.simple_list_item_1,
  items));
  toptext=(TextView)findViewById(R.id.toptext);
 }

public void onListItemClick(ListView parent, View v, int position,
 long id) {
     Intent intent = new Intent();

     if (parent.getItemAtPosition(position)=="Atlanta")
     {
           //THIS IS WHERE I WISH TO INSERT "ZONE 1", "ZONE 2", "ZONE 3" 
                  //between Atlanta and Boston in the list
     }
     else if (parent.getItemAtPosition(position)=="Boston")
     {
          intent.setClass(this, test.lists.special.Boston.class);
           startActivity(intent); 
     }
     else if (parent.getItemAtPosition(position)=="Chicago")
     {
             intent.setClass(this, test.lists.special.Chicago.class);
              startActivity(intent); 
     }
     else if (parent.getItemAtPosition(position)=="Dallas")
     {
            intent.setClass(this, test.lists.special.Dallas.class);
             startActivity(intent); 
     }
     else if (parent.getItemAtPosition(position)=="Zone 1")
     {
            intent.setClass(this, test.lists.special.Atlanta.Zone1.class);
             startActivity(intent); 
     }
     else if (parent.getItemAtPosition(position)=="Zone 2")
     {
            intent.setClass(this, test.lists.special.Atlanta.Zone2.class);
             startActivity(intent); 
     }
     else if (parent.getItemAtPosition(position)=="Zone 3")
     {
            intent.setClass(this, test.lists.special.Atlanta.Zone3.class);
             startActivity(intent); 
     }
    }

}

Answer 1

下面的工作和测试代码:

import android.app.ListActivity; 
import android.content.Intent; 
import android.os.Bundle; 
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View; 
import android.view.ViewGroup;
import android.widget.ArrayAdapter; 
import android.widget.Button;
import android.widget.ImageView;
import android.widget.ListView; 
import android.widget.TextView; 
import android.widget.Toast; 

public class SpecialList extends ListActivity{ 

    TextView toptext; 
    String[] items={"Atlanta", "Boston", "Chicago", "Dallas"};
    private CityListAdapter mListOfCities;

    boolean mAtlantaListExpanded;

    @Override 
    public void onCreate(Bundle icicle) { 
        super.onCreate(icicle); 
        setContentView(R.layout.main); 

        mAtlantaListExpanded = false;
        mListOfCities = new CityListAdapter();
        setListAdapter(mListOfCities);

        for (int n=0; n < items.length; n++)
        {
            mListOfCities.add(items[n]);
        }
    } 

    public void onListItemClick(ListView parent, View v, int position, long id) 
    { 
         Intent intent = new Intent(); 

         if (parent.getItemAtPosition(position)=="Atlanta") 
         { 
             mAtlantaListExpanded = !mAtlantaListExpanded;
             mListOfCities.clear();
             for (int n=0; n < items.length; n++)
             {
                mListOfCities.add(items[n]);
             }           
             Log.i("SpecialList", "Atlanta");            
         } 
         else if (parent.getItemAtPosition(position)=="Boston") 
         { 
             Log.i("SpecialList", "Boston");
         } 
         else if (parent.getItemAtPosition(position)=="Chicago") 
         { 
             Log.i("SpecialList", "Chicago");
         } 
         else if (parent.getItemAtPosition(position)=="Dallas") 
         { 
             Log.i("SpecialList", "Dallas");
         } 
    }

    class CityListAdapter extends ArrayAdapter<String> {    

        CityListAdapter() {         
            super(SpecialList.this, R.layout.one_city_row);
        }

        @Override
        public View getView(int position, View convertView, ViewGroup parent) 
        {
            View row = null;
            LayoutInflater inflater = getLayoutInflater();

            if ((position == 0) && (!mAtlantaListExpanded))
            {
                row = inflater.inflate(R.layout.expandable_city_row, parent, false);
                TextView city = (TextView) row.findViewById(R.id.Expandable_TextView01);
                city.setText(items[position]);

                TextView cityZone1 = (TextView) row.findViewById(R.id.Zone_TextView01);
                cityZone1.setText("Zone 1");

                TextView cityZone2 = (TextView) row.findViewById(R.id.Zone_TextView02);
                cityZone2.setText("Zone 2");

                TextView cityZone3 = (TextView) row.findViewById(R.id.Zone_TextView03);
                cityZone3.setText("Zone 3");

                cityZone1.setOnClickListener(
                    new Button.OnClickListener() {
                        @Override
                        public void onClick(View v) {
                             Log.i("SpecialList", "Zone 1");
                        }
                    }
                );

                cityZone2.setOnClickListener(
                    new Button.OnClickListener() {
                        @Override
                        public void onClick(View v) {
                             Log.i("SpecialList", "Zone 2");
                        }
                    }
                );

                cityZone3.setOnClickListener(
                    new Button.OnClickListener() {
                        @Override
                        public void onClick(View v) {
                             Log.i("SpecialList", "Zone 3");
                        }
                    }
                );              
            }
            else
            {
                row = inflater.inflate(R.layout.one_city_row, parent, false);
                TextView city = (TextView) row.findViewById(R.id.City_TextView01);
                city.setText(items[position]);
            }                   

            return(row);
        }
    }
} 

点击“亚特兰大”会导致列表重绘，在仅显示“亚特兰大”或展开列表之间切换。 R.layout.one_city_row.xml 是一个 TextView 的简单布局，R.layout.Expandable_city_row.xml 有额外的子选项作为 TextView 元素，可以从附加的代码中得出结论 fragment 。

使用这种方法，您可以根据需要完全自定义列表。在我放置 Log.i() 的地方，您应该放置您的 Intent 。