android读取sqlite数据库的数据并用listview显示

【实例截图】

【核心代码】

package kaoqin.xxf.com.kaoqin;

import android.database.sqlite.SQLiteDatabase;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ListView;
import android.database.Cursor;
import android.widget.TextView;

import org.w3c.dom.Text;

import java.util.ArrayList;

public class MainActivity extends AppCompatActivity {

    //private SQLiteDatabase sd;
    //private MyOpenHelper moh;
    private ListView lv;
    private ArrayList<Student> studentlist;


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

        studentlist = new ArrayList<>();
        SQLdm s = new SQLdm();
        SQLiteDatabase db = s.openDatabase(getApplicationContext());
        Cursor cursor = db.rawQuery("select * from yidong",null);
        while(cursor.moveToNext()){
            String name = cursor.getString(cursor.getColumnIndex("name"));
            String xuehao = cursor.getString(cursor.getColumnIndex("xuehao"));
            String Class = cursor.getString(cursor.getColumnIndex("Class"));
            Student st = new Student(name,Class,xuehao);
            studentlist.add(st);
        }
        lv = (ListView)findViewById(R.id.student_lv);
        lv.setAdapter(new BaseAdapter() {
            /*
             * 为ListView设置一个适配器
             * getCount()返回数据个数
             * getView()为每一行设置一个条目
             * */
            @Override
            public int getCount() {
                return studentlist.size();
            }

            @Override
            public Object getItem(int position) {
               // return studentlist.get(position);
                return null;
            }

            @Override
            public long getItemId(int position) {

               // return position;
                return 0;
            }

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


                View view ;
                /**对ListView的优化，convertView为空时，创建一个新视图；
                 * convertView不为空时，代表它是滚出,
                 * 放入Recycler中的视图,若需要用到其他layout，
                 * 则用inflate(),同一视图，用fiindViewBy()
                 * **/
                if(convertView == null )
                {
                    LayoutInflater inflater = MainActivity.this.getLayoutInflater();
                    view = inflater.inflate(R.layout.item,null);
                   //view = View.inflate(getBaseContext(),R.layout.item,null);
                }
                else
                {
                     view = convertView;
                }
                //从studentlist中取出一行数据，position相当于数组下标,可以实现逐行取数据
                Student st = studentlist.get(position);
                //TextView name = (TextView) LayoutInflater.from(MainActivity.this).inflate(R.layout.item, null).findViewById(R.id.stu_name);
                //TextView xuehao = (TextView) LayoutInflater.from(MainActivity.this).inflate(R.layout.item, null).findViewById(R.id.stu_number);
                //TextView Class = (TextView) LayoutInflater.from(MainActivity.this).inflate(R.layout.item, null).findViewById(R.id.stu_age);
                TextView name = (TextView)view.findViewById(R.id.stu_name);
                TextView xuehao  = (TextView)view.findViewById(R.id.stu_number);
                TextView Class = (TextView)view.findViewById(R.id.stu_age);

                xuehao.setText(st.getXuehao());
                name.setText(st.getName());
                Class.setText(st.getclass());

                return view;
            }
        });

    }



}