增删改查

package com.example.lwj;

import java.awt.Cursor;
import java.awt.List;

import android.R;
import android.os.Bundle;
import android.app.Activity;
import android.database.sqlite.SQLiteDatabase;
import android.view.Menu;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ListAdapter;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;

public class MainActivity extends Activity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_list_item);
    }
     public void add(View v) {
            StuOpenHelper helper = new StuOpenHelper(this);
            SQLiteDatabase db = helper.getWritableDatabase();
            String name = ((EditText) findViewById(R.id.et_name)).getText()
                    .toString();
            int age = Integer.parseInt(((EditText) findViewById(R.id.et_age))
                    .getText().toString());
            db.execSQL("insert into stuinfo (name,age) values(?,?)", new Object[] {
                    name, age });
            Toast.makeText(this, "ok", 0).show();
        }
     
        public void delete(View view) {
            StuOpenHelper helper = new StuOpenHelper(this);
            SQLiteDatabase db = helper.getWritableDatabase();
            db.execSQL("delete from stuinfo where _id=?", new Object[] { 2 });
            Toast.makeText(this, "ɾ���ɹ�", 0).show();
     
        }
     
        public void update(View view) {
            StuOpenHelper helper = new StuOpenHelper(this);
            SQLiteDatabase db = helper.getWritableDatabase();
            db.execSQL("update stuinfo set name=? where _id=?", new Object[] {
                    "micky", 3 });
            Toast.makeText(this, "�޸ijɹ�", 0).show();
     
        }
        List<Student> list=new ArrayList<Student>();
     
        public void search(View view) {
            System.out.println(list.size()+"��search��");
            StuOpenHelper helper = new StuOpenHelper(this);
            SQLiteDatabase db = helper.getWritableDatabase();
            Cursor cursor = db.rawQuery("select * from stuinfo", null);
            if (((AdapterView<ListAdapter>) cursor).getCount() != 0) {
                while (cursor.moveToNext()) {
                    stu s1=new stu();
                    s1.setId(cursor.getInt(0));
                    s1.setName(cursor.getString(1));
                    s1.setAge(cursor.getInt(2));
                    list.add(s1);
                     
                }
            }
            ListView lv=(ListView) findViewById(R.id.lv1);
            lv.setAdapter(new myadapter());
        }
        private class myadapter extends BaseAdapter{
     
            @Override
            public int getCount() {
                // TODO Auto-generated method stub
                return list.size();
            }
            @Override
            public View getView(int position, View convertView, ViewGroup arg2) {
         
                // TODO Auto-generated method stub
                View view=View.inflate(MainActivity.this, R.layout.list_item, null);
                TextView tvid=(TextView)view.findViewById(R.id.tv_id);
                TextView tvname=(TextView)view.findViewById(R.id.tv_name);
                TextView tvage=(TextView) view.findViewById(R.id.background);
         
                Bundle list;
                System.out.println(list.get(position).getId());        
                tvid.setText(list.get(position).getId()+"");
                tvname.setText(List.get(position).getName());
                tvage.setText(list.get(position).getAge()+"");     
                return view;
            }
     
     
     
            public Object getItem(int arg0) {
                // TODO Auto-generated method stub
                return null;
            }
     
     
     
            public long getItemId(int arg0) {
                // TODO Auto-generated method stub
                return 0;
            }
             
        }
     
    }

import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;


public class StuOpenHelper extends SQLiteOpenHelper{
     public StuOpenHelper(Context context) {
            super(context, "stu.db", null, 1);
            // TODO Auto-generated constructor stu
        }
     @Override
        public void onCreate(SQLiteDatabase db) {
            // TODO Auto-generated method stub
            db.execSQL("create table stuinfo(_id integer primary key autoincrement,name varchar(20),age integer)");
     
        }
     
        @Override
        public void onUpgrade(SQLiteDatabase arg0, int arg1, int arg2) {
            // TODO Auto-generated method stub
     
        }
     
    }
           

public class stu {
     private int id;
        private String name;
        private int age;
        public int getId() {
            return id;
        }
        public void setId(int id) {
            this.id = id;
        }
        public String getName() {
            return name;
        }
        public void setName(String name) {
            this.name = name;
        }
        public int getAge() {
            return age;
        }
        public void setAge(int age) {
            this.age = age;
        }
     
    }

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@drawable/bg"
    android:orientation="vertical"
    android:padding="16dp" >
 
    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="130dp" >
 
        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="姓  名 ："
            android:textSize="18sp" />
 
        <EditText
            android:id="@+id/et_name"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:hint="请输入姓名"
            android:textSize="16sp" />
    </LinearLayout>
 
    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginBottom="10dp" >
 
        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="年  龄："
            android:textSize="18sp" />
 
        <EditText
            android:id="@+id/et_age"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:hint="输入年龄"
            android:textSize="16sp" />
    </LinearLayout>
 
    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content" >
 
        <Button
            android:id="@+id/btn_add"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_marginRight="2dp"
            android:layout_weight="1"
            android:background="#B9B9FF"
            android:onClick="add"
            android:text="添加"
            android:textSize="18sp" />
 
        <Button
            android:id="@+id/btn_query"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_marginRight="2dp"
            android:layout_weight="1"
            android:background="#DCB5FF"
            android:onClick="search"
            android:text="查询"
            android:textSize="18sp" />
 
        <Button
            android:id="@+id/btn_update"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_marginRight="2dp"
            android:layout_weight="1"
            android:background="#E6CAFF"
            android:onClick="update"
            android:text="修改"
            android:textSize="18sp" />
 
        <Button
            android:id="@+id/btn_delete"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:background="#ACD6FF"
            android:onClick="delete"
            android:text="删除"
            android:textSize="18sp" />
    </LinearLayout>
 
    
 
        <ListView
            android:id="@+id/lv1"
            android:layout_width="fill_parent"
            android:layout_height="fill_parent"
            android:layout_marginTop="25dp"
            android:textSize="20sp" />
    
</LinearLayout>

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="horizontal" >
 
    <TextView
        android:id="@+id/tv_id"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_weight="1"
        android:text="1" />
 
    <TextView
        android:id="@+id/tv_name"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_weight="1"
        android:text="2" />
 
    <TextView
        android:id="@+id/tv_age"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_weight="1"
        android:text="3" />
 
</LinearLayout>