Android studio，使用greenDao第三方数据库框架操作数据库

因项目有需求，需建一个数据库来存储数据，数据库选型就选了当前比较流行，性能也比较好的greenDao，目前使用的版本是3.2.0，简单易用，下面具体说下使用的步骤：

1.在build.gradle文件导入配置文件，导入包

//greenDao----start//
apply plugin: 'org.greenrobot.greendao'
buildscript {
repositories {
mavenCentral()
}
dependencies {
classpath 'org.greenrobot:greendao-gradle-plugin:3.2.0'
}
}
greendao {
schemaVersion 1    //<--数据库的版本，用于升级时候进行更改
daoPackage 'com.example.pc.teste6.dao'     //存放自动生成代码的包
targetGenDir 'src/main/java'                  //...
}
//greenDao----end//

//greeDao所需要的支持
compile 'org.greenrobot:greendao:3.2.0'
compile 'org.greenrobot:greendao-generator:3.2.0'

2.greenDao非常智能化，接着只需写你的数据库实体类，就能生成对应的表了，例如

public class UserObject {

//这个注解就表明下面那个id是个主键，必须用Long，否则会报错，autoincrement=true自增
@Id(autoincrement = true)
Long id;
@NotNull
String name;
//不为空
@NotNull
Integer age;

}

接着按Ctrl+F9,就会生成get和set方法，并且在你的dao包下生成数据库文件和dao类

@Entity
public class UserObject {

//这个注解就表明下面那个id是个主键，必须用Long，否则会报错，autoincrement=true自增
@Id(autoincrement = true)
Long id;
@NotNull
String name;
//不为空
@NotNull
Integer age;
@Generated(hash = 824938356)
public UserObject(Long id, @NotNull String name, @NotNull Integer age) {
this.id = id;
this.name = name;
this.age = age;
}
@Generated(hash = 1300257024)
public UserObject() {
}
public Long getId() {
return this.id;
}
public void setId(Long id) {
this.id = id;
}
public String getName() {
return this.name;
}
public void setName(String name) {
this.name = name;
}
public Integer getAge() {
return this.age;
}
public void setAge(Integer age) {
this.age = age;
}

3.写一个DBDaoUtil类，操作数据库

public class DBDaoUtil {

private static DaoSession daoSession;
private static DaoSession getDaoSession(Context context) {
if (daoSession==null) {
DaoMaster.OpenHelper openHelper = new DaoMaster.OpenHelper(context, "student"){
@Override
public void onUpgrade(Database db, int oldVersion, int newVersion) {
switch (oldVersion) {
case 1:
db.beginTransaction();
db.execSQL("...");
db.setTransactionSuccessful();
db.endTransaction();
break;
}
}
};
SQLiteDatabase db = openHelper.getWritableDatabase();
DaoMaster daoMaster = new DaoMaster(db);
daoSession = daoMaster.newSession();
}
return daoSession;
}

public static UserObjectDao getUserDao(Context context) {
return getDaoSession(context).getUserObjectDao();
}
}

4.通过mainActivity,操作数据库

activity_main.xml文件

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/activity_main"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context="com.example.pc.teste6.MainActivity">

<LinearLayout
android:id="@+id/dataLL"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal">
<Button
android:id=<
ff37
strong>"@+id/add"
[/b]android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@+id/network"
android:text="增"/>
<Button
android:id="@+id/delete"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@+id/add"
android:text="删"/>
<Button
android:id="@+id/update"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@+id/delete"
android:text="改"/>
<Button
android:id="@+id/select"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@+id/update"
android:text="查"/>

</LinearLayout>

<ListView
android:id="@+id/dataLV"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_below="@+id/dataLL">

</ListView>
</RelativeLayout>

Mainactivity

importandroid.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
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.Button;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;

import com.example.pc.teste6.bean.UserObject;
import com.example.pc.teste6.dao.UserObjectDao;
import com.example.pc.teste6.receiver.BatteryReceiver;
import com.example.pc.teste6.util.DBDaoUtil;
import com.example.pc.teste6.util.NetUtil;

import java.util.ArrayList;
import java.util.List;

public class MainActivity extends AppCompatActivity implements View.OnClickListener{

private Context context;
private Button addBtn,deleteBtn,updateBtn,selectBtn;//增删改查
private ListView dataLV;
private DataAdapter adapter;
private UserObjectDao userDao;
private int i=1;

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

initView();
initData();

}

/**
* 初始化控件
*/
private void initView(){
addBtn= (Button) findViewById(R.id.add);
deleteBtn= (Button) findViewById(R.id.delete);
updateBtn= (Button) findViewById(R.id.update);
selectBtn= (Button) findViewById(R.id.select);
dataLV= (ListView) findViewById(R.id.dataLV);

addBtn.setOnClickListener(this);
deleteBtn.setOnClickListener(this);
updateBtn.setOnClickListener(this);
selectBtn.setOnClickListener(this);

}

/**
* 初始化数据
*/
private void initData(){

userDao = DBDaoUtil.getUserDao(context);//初始化dao

adapter=new DataAdapter(context);
dataLV.setAdapter(adapter);

}

@Override
public void onClick(View view) {
switch (view.getId()){

case R.id.add:
UserObject ub1=new UserObject();
ub1.setName("小小英"+i);
ub1.setAge(100);
userDao.insert(ub1);
List<UserObject> list1=userDao.loadAll();
adapter.addData(list1);
i++;
break;
case R.id.delete:
userDao.deleteByKey(Long.parseLong(i+""));
List<UserObject> list2=userDao.loadAll();
adapter.addData(list2);
break;
case R.id.update:
UserObject ub3=new UserObject();
ub3.setId(Long.parseLong(i+""));
userDao.update(ub3);
List<UserObject> list3=userDao.loadAll();
adapter.addData(list3);
break;
case R.id.select://查询数据
List<UserObject> list4=userDao.loadAll();
adapter.addData(list4);
Toast.makeText(context,""+list4.size(),Toast.LENGTH_SHORT).show();
break;
default:
break;

}
}

class DataAdapter extends BaseAdapter{

private Context context;
private List<UserObject> mList;

public DataAdapter(Context context) {
this.context = context;
}

public void addData(List<UserObject> mList){
this.mList=mList;
notifyDataSetChanged();
}

@Override
public int getCount() {
return (mList!=null)?mList.size():1;
}

@Override
public Object getItem(int i) {
return mList.get(i);
}

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

@Override
public View getView(int i, View view, ViewGroup viewGroup) {

view = LayoutInflater.from(context).inflate(R.layout.lv_item,null);
if(mList!=null&&mList.size()!=0){
TextView idTV= (TextView) view.findViewById(R.id.idTV);
idTV.setText(mList.get(i).getId()+"");
TextView nameTV= (TextView) view.findViewById(R.id.nameTv);
nameTV.setText(mList.get(i).getName());
TextView ageTV= (TextView) view.findViewById(R.id.ageTv);
ageTV.setText(mList.get(i).getAge()+"");
}
return view;
}
}

}

这样就可以操作数据库了

我的心愿是世界和平。。。