增删改查

<?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>

package cn.itcast.directory;

import java.util.ArrayList;
import java.util.List;
import android.os.Bundle;
import android.app.Activity;
import android.content.ContentValues;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.view.Menu;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.EditText;
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_main);
	}

	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 (cursor.getCount() != 0) {
			while (cursor.moveToNext()) {
				Student s1=new Student();
				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.tv_age);
	
			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;
		}



		@Override
		public Object getItem(int arg0) {
			// TODO Auto-generated method stub
			return null;
		}



		@Override
		public long getItemId(int arg0) {
			// TODO Auto-generated method stub
			return 0;
		}
		
	}

}

　

package cn.itcast.directory;

public class Student {
	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;
	}

}

　　

package cn.itcast.directory;

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

public class StuOpenHelper extends SQLiteOpenHelper {

	public StuOpenHelper(Context context) {
		super(context, "stu.db", null, 1);
		// TODO Auto-generated constructor stub
	}

	@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

	}

}