Android 开源数据库框架 - LitePal 的使用
<h2>简介</h2> <p>LitePal是一款开源的Android数据库框架,采用了关系映射的模式。LitePal在github上的项目地址: <a href="/misc/goto?guid=4959746370674825430" rel="nofollow,noindex">https://github.com/LitePalFramework/LitePal</a></p> <h2>配置LitePal</h2> <pre> <code class="language-xml">dependencies { .... compile 'org.litepal.android:core:1.5.1' }</code></pre> <p>在app/src/main 目录下新建目录assets,在assets目录下建litepal.xml 文件</p> <pre> <code class="language-xml"><?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> <p>标签用于指定数据库名</p> <p>标签用于指定版本号</p> <p>标签用于指定所有的映射模型</p> <p>在清单文件中配置LitePalApplication</p> <pre> <code class="language-xml"><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> <h2>实战</h2> <p>创建JavaBean</p> <p>Person.java</p> <pre> <code class="language-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> <p>增删改查数据库</p> <p>MainActivity.java</p> <pre> <code class="language-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) { //创建数据库 Connector.getDatabase(); } }); mAddData.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { Person person = new Person(); person.setId(1); person.setName("周润发"); person.setAge(62); person.setWeight("80kg"); person.save(); person.clearSavedState(); person.setId(2); person.setName("周杰伦"); person.setAge(45); person.setWeight("65kg"); person.save(); person.clearSavedState(); person.setId(3); person.setName("周星驰"); person.setAge(65); person.setWeight("70kg"); person.save(); Toast.makeText(MainActivity.this, "添加数据成功", Toast.LENGTH_SHORT).show(); } }); mUpdateData.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { Person person = new Person(); //把id = 3 的那个人 姓名更改为周建 年龄改为28 体重改为62kg person.setName("周建"); person.setAge(28); person.setWeight("62kg"); person.updateAll("id = ?", "3"); Toast.makeText(MainActivity.this, "更新数据成功", Toast.LENGTH_SHORT).show(); } }); mDeleteButton.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { //删除年龄大于60的人 DataSupport.deleteAll(Person.class, "age > ?", "60"); Toast.makeText(MainActivity.this, "删除数据成功", 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, "查询数据成功", Toast.LENGTH_SHORT).show(); } }); } }</code></pre> <p> </p> <p>来自:https://juejin.im/post/58db82b35c497d00571308b8</p> <p></p> <p> </p>
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