android 中listview添加数据,以及listview优化

1.先看一个listview添加string数据:新建一个项目,ListViewDemo，MainActivity.java代码如下:

public class MainActivity extends Activity {
    String[]  nameList ={"banbana","apple","orange","Watermelon","Pear","Grape"};
     private ListView listview;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        listview =(ListView)findViewById(R.id.listview);
        addString();
    }
    private void addString(){
        ArrayAdapter adapter =new ArrayAdapter(this,android.R.layout.simple_list_item_1,nameList);
        listview.setAdapter(adapter);
    }
}

，这里面对listview添加的设配器是用系统的,ArrayAdapter (Context context, int resource, T[] objects)，三个参数,第一个是context，第二个就是资源文件的id,三单个就是object数组. 再看一下xml文件:

只有一个listview,运行程序,如下: ,如果想去掉listview的横线:

        listview.setDividerHeight(0);//屏蔽掉listview的横线
        listview.setDivider(null);

  2.listview添加一张图片和文字

     修改MainActivity.java代码如下:

public class MainActivity extends Activity {
     private ListView listview;
    String [] lefttitles={"个人信息","健康周报","跑步","设备管理","设置","关于"};
    int [] leftImageList={R.mipmap.sliding_personal_info,R.mipmap.sliding_health_news,R.mipmap.sliding_run,
            R.mipmap.sliding_device_manage,R.mipmap.sliding_setting,R.mipmap.sliding_about};
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        listview =(ListView)findViewById(R.id.listview);
       addImage();
    }
    private void addImage(){
        listview.setAdapter(new SlidingListviewAdapter(this,lefttitles,leftImageList));
    }

其中leftImageList的文件就是自己存放在mipmap下的资源文件,看下这个SlidingListciewAdapter代码:

public class SlidingListviewAdapter extends BaseAdapter {
    View [] itemViews;
    LayoutInflater la;
    public SlidingListviewAdapter(Context c, String [] itemTitles, int [] itemImageRes){
        itemViews = new View[itemTitles.length];
        la=LayoutInflater.from(c);
        for (int i=0; i

 getCount()方法(在此适配器中所代表的数据集中的条目数),getItem(int position) (获取数据集中与指定索引对应的数据项),

getItemId(int position)(取在列表中与指定索引对应的行id),每个子项被滚动到屏幕内的时候会调用getView()方法,效果如下:

源码(ListviewDemo)