Android 開源數據庫框架 - LitePal 的使用

簡介

LitePal是一款開源的Android數據庫框架，采用了關系映射的模式。LitePal在github上的項目地址： https://github.com/LitePalFramework/LitePal

配置LitePal

dependencies {
 ....
 compile 'org.litepal.android:core:1.5.1'
}

在app/src/main 目錄下新建目錄assets，在assets目錄下建litepal.xml 文件

<?xml version="1.0" encoding="utf-8"?>
<litepal>
    <dbname value="Person" ></dbname>


<version value="1" ></version>

<list>
    <mapping class="com.zhoujian.litepal.bean.Person"></mapping>
</list>

</litepal></code></pre> 
  
標簽用于指定數據庫名
 
  
標簽用于指定版本號
 
  
標簽用于指定所有的映射模型
 
  
在清單文件中配置LitePalApplication
 
  
<application
        android:name="org.litepal.LitePalApplication"
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
        <activity android:name=".activity.MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN"/>


            <category android:name="android.intent.category.LAUNCHER"/>
        </intent-filter>
    </activity>
</application></code></pre> 

實戰
 
  
創建JavaBean
 
  
Person.java
 
  
package com.zhoujian.litepal.bean;

import org.litepal.crud.DataSupport;
/**

Created by zhoujian on 2017/3/29.
*/

public class Person extends DataSupport
{
    private String name;

private int age;

private int id;

private String weight;

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;
}

public String getWeight() {
    return weight;
}

public void setWeight(String weight) {
    this.weight = weight;
}

public int getId() {
    return id;
}

public void setId(int id) {
    this.id = id;
}

}</code></pre> 
  
增刪改查數據庫
 
  
MainActivity.java
 
  
package com.zhoujian.litepal.activity;

import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.Toast;
import com.zhoujian.litepal.R;
import com.zhoujian.litepal.bean.Person;
import org.litepal.crud.DataSupport;
import org.litepal.tablemanager.Connector;
import java.util.List;
public class MainActivity extends AppCompatActivity
{

private Button mCreateDatabase;
private Button mAddData;
private Button mUpdateData;
private Button mDeleteButton;
private Button mQueryButton;

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

    clickEvents();
}


private void initViews()
{
    mCreateDatabase = (Button) findViewById(R.id.create_database);
    mAddData = (Button) findViewById(R.id.add_data);
    mUpdateData = (Button) findViewById(R.id.update_data);
    mDeleteButton = (Button) findViewById(R.id.delete_data);
    mQueryButton = (Button) findViewById(R.id.query_data);
}

private void clickEvents()
{
    mCreateDatabase.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            //創建數據庫
            Connector.getDatabase();
        }
    });


    mAddData.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {

            Person person = new Person();
            person.setId(1);
            person.setName("周潤發");
            person.setAge(62);
            person.setWeight("80kg");
            person.save();

            person.clearSavedState();
            person.setId(2);
            person.setName("周杰倫");
            person.setAge(45);
            person.setWeight("65kg");
            person.save();

            person.clearSavedState();
            person.setId(3);
            person.setName("周星馳");
            person.setAge(65);
            person.setWeight("70kg");
            person.save();

            Toast.makeText(MainActivity.this, "添加數據成功", Toast.LENGTH_SHORT).show();
        }
    });

    mUpdateData.setOnClickListener(new View.OnClickListener()
    {
        @Override
        public void onClick(View v) {
            Person person = new Person();

            //把id = 3 的那個人 姓名更改為周建  年齡改為28   體重改為62kg
            person.setName("周建");
            person.setAge(28);
            person.setWeight("62kg");
            person.updateAll("id = ?", "3");

            Toast.makeText(MainActivity.this, "更新數據成功", Toast.LENGTH_SHORT).show();

        }
    });

    mDeleteButton.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v)
        {
            //刪除年齡大于60的人
            DataSupport.deleteAll(Person.class, "age > ?", "60");
            Toast.makeText(MainActivity.this, "刪除數據成功", Toast.LENGTH_SHORT).show();
        }
    });



    mQueryButton.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v)
        {
            List<Person> persons = DataSupport.findAll(Person.class);
            for (Person person: persons) {
                Log.d("MainActivity", "person name is " + person.getName());
                Log.d("MainActivity", "person weight is " + person.getWeight());
                Log.d("MainActivity", "person age is " + person.getAge());
                Log.d("MainActivity", "person id is " + person.getId());
            }

            Toast.makeText(MainActivity.this, "查詢數據成功", Toast.LENGTH_SHORT).show();
        }
    });

}

}</code></pre> 
  
  
  
來自：https://juejin.im/post/58db82b35c497d00571308b8