实例讲解Androidapp开发中ListView的基本使用及优化

情景模式1
情景模式2 
情景模式3

listview = (ListView) findViewById(R.id.listView1);
 ArrayAdapter adapter = ArrayAdapter.createFromResource(this,R.array.ctype, android.R.layout.simple_list_item_checked);
    listview.setAdapter(adapter);

public class ActivityMain extends ListActivity {
  @Override
  protected void onCreate(Bundle savedInstanceState) {

    super.onCreate(savedInstanceState);
    String[] ctype ={"1","2","3"}; 
    ArrayAdapter adapter = new ArrayAdapter(this,android.R.layout.simple_list_item_1,ctype);
    setListAdapter(adapter);

  }

  @Override
  protected void onListItemClick(ListView l, View v, int position, long id) {

    super.onListItemClick(l, v, position, id);
  }


}

<&＃63;xml version="1.0" encoding="utf-8"&＃63;>

 
    

public class MainActivity extends Activity {
  @Override
  public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);
    ListView listview = (ListView) findViewById(R.id.listView1); // 获取列表视图
    int[] imageId = new int[] { R.drawable.img01, R.drawable.img02,
        R.drawable.img03, R.drawable.img04, R.drawable.img05,
        R.drawable.img06, R.drawable.img07, R.drawable.img08 }; // 定义并初始化保存图片id的数组
    String[] title = new String[] { "保密设置", "安全", "系统设置", "上网", "我的文档",
        "GPS导航", "我的音乐", "E-mail" }; // 定义并初始化保存列表项文字的数组
    List> listItems = new ArrayList>(); // 创建一个list集合
    // 通过for循环将图片id和列表项文字放到Map中，并添加到list集合中
    for (int i = 0; i  map = new HashMap(); // 实例化Map对象
      map.put("image", imageId[i]);
      map.put("title", title[i]);
      listItems.add(map); // 将map对象添加到List集合中
    }

    SimpleAdapter adapter = new SimpleAdapter(this, listItems,
        R.layout.items, new String[] { "title", "image" }, new int[] {
            R.id.title, R.id.image }); // 创建SimpleAdapter
    listview.setAdapter(adapter); // 将适配器与ListView关联

  }
}

<&＃63;xml version="1.0" encoding="utf-8"&＃63;>


  

  

  

public class MainActivity extends Activity {
  private ListView lv;
  private List infos;
  private Random random;

  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    lv = (ListView) findViewById(R.id.listView1);
    infos = new ArrayList();
//通过for循环将name和number添加到List集合中
    for (int i = 0; i <100; i++) {
      MyInfo userInfo = new MyInfo();
      userInfo.setName("name"+i);
      userInfo.setNumber("number"+i);
      infos.add(userInfo);
      System.out.println(userInfo.toString());  
    }

    lv.setAdapter(new MyAdapter());
  }

  private class MyAdapter extends BaseAdapter{

    @Override
    public int getCount() {
      return infos.size();//返回listview的长度
    }
    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
      MyInfo userInfo = infos.get(position);
      View view;
      ViewHolder holder;
      //减少内存中view对象创建的次数
      if (convertView != null && convertView instanceof RelativeLayout) {
        view = convertView;//复用已经回收掉的view对象
        holder = (ViewHolder) view.getTag();//得到他们的引用
      } else {
        view = View.inflate(getApplicationContext(),
            R.layout.item_layout, null);//把布局文件转化成View对象
        holder = new ViewHolder();
        //把ID存到存到holder对象中
        //注意是在view下findViewById
        holder.iv = (ImageView) view.findViewById(R.id.imageView1);
        holder.tv1 = (TextView) view.findViewById(R.id.textView1);
        holder.tv2 = (TextView) view.findViewById(R.id.textView2);
        view.setTag(holder);//对象创建出来时找到他们的引用存到holder中
      }
      holder.tv1.setText(infos.get(position).getName());
      holder.tv2.setText(infos.get(position).getNumber());
      return view;
    }
    @Override
    public Object getItem(int position) {      
      return null;
    }

    @Override
    public long getItemId(int position) {      
      return 0;
    }    

  }
  /*
   * view对象的容器记录View对象的内存地址相当于一个记事本
   */
  static class ViewHolder{
    TextView tv1;
    TextView tv2;
    ImageView iv;
  }

}
public class MyInfo {
  private String name; 
  private String number;//也可以添加Bitmap

  @Override
  public String toString() {
    return "MyInfo [name=" + name + ", number=" + number + "]";
  }
  public String getName() {
    return name;
  }
  public void setName(String name) {
    this.name = name;
  }
  public String getNumber() {
    return number;
  }
  public void setNumber(String number) {
    this.number = number;
  }


}

holder.iv = (ImageView) view.findViewById(R.id.imageView1);