Question

我在android中创建了一个简单的应用程序列表视图，因为我想在选择项目时做一个祝酒词，我尝试过如下但是它不起作用..

我的代码如下：

main.java

    package com.example.listview;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;

import android.os.Bundle;
import android.app.Activity;
import android.app.ListActivity;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.SimpleAdapter;
import android.widget.Toast;
import android.support.v4.app.NavUtils;

public class ListViewActivity extends Activity {


    String items[]={"Car","Bird","Bike","Flower"};
    String category[]={"Sports","Birds","Sports","Nature"};
    int icons[]={R.drawable.car,R.drawable.bird,R.drawable.bike,R.drawable.flower};

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_list_view);
        List <HashMap<String,String>> aList=new ArrayList<HashMap<String,String>>();
        for(int i=0;i<4;i++)
        {
            HashMap<String,String> hm=new HashMap<String, String>();
            hm.put("txt","Item : "+items[i]);
            hm.put("category","Category : "+category[i]);
            hm.put("icon",Integer.toString(icons[i]));
            aList.add(hm);
        }
        String []from={"icon","txt","category"};
        int []to={R.id.image,R.id.text,R.id.category};
        SimpleAdapter adapter=new SimpleAdapter(getBaseContext(),aList,R.layout.list,from,to);
        final ListView lv=(ListView)findViewById(R.id.listView);
        lv.setAdapter(adapter);
        lv.setOnItemClickListener(new OnItemClickListener() {

            public void onItemClick(AdapterView<?> arg0, View arg1, int position,
                    long arg3) {
                // TODO Auto-generated method stub
                String selectedValue =(String) (lv.getItemAtPosition(position));
                Toast.makeText(getApplicationContext(),selectedValue , Toast.LENGTH_LONG).show();
            }
    });
    }


}

请提前帮助我...

Answer 1

我希望通过这种方式获得所选项目

      lv.setOnItemClickListener(new OnItemClickListener() {

                    public void onItemClick(AdapterView<?> arg0, View arg1, int position,
                            long arg3) {
                        // TODO Auto-generated method stub
                     //  Toast.makeText(getApplicationContext(),"Position is: "+ position, Toast.LENGTH_LONG).show();
                       String selectedFromList = lv.getItemAtPosition(position).toString();
                        Toast.makeText(getApplicationContext(),selectedFromList , Toast.LENGTH_LONG).show();
                    }
            });

Answer 2

HashMap<String, String> selectedValue = (HashMap<String, String>) (lv.getItemAtPosition(position));         
ArrayList<String> list = new ArrayList<String>(selectedValue.keySet());             
Toast.makeText(getApplicationContext(), selectedValue.get("txt"), Toast.LENGTH_LONG).show();

该hashmap具有list中存在的密钥。该列表实际上是您给出的from数组。只需给出相应的键即可显示相应的文本。

它的工作。：）

Answer 3

尝试

String selectedValue = from[position];

Answer 4

您可以使用适配器并从中获取值。

public void onItemClick(AdapterView<?> arg0, View arg1, int position, long arg3) 
            String selectedValue =(String) (lv.getAdapter().getItem(position));
            Toast.makeText(getApplicationContext(),Toast.LENGTH_LONG).show();
        }

Answer 5

我对你在做什么很困惑，你为什么不这样做：

String selectedValue = items[position];

而不是：

String selectedValue =(String) (lv.getItemAtPosition(position));

Toast不从列表中的选定项生成文本

5 个答案: