android：kotlin语言使用greendao3.0简解

先看效果

步骤一、在自己的build.gradle中加入这些配置

• 在app的build.gradle中

apply plugin: 'org.greenrobot.greendao'greendao {    //数据库的schema版本，也可以理解为数据库版本号    schemaVersion 1    //设置DaoMaster、DaoSession、Dao包名，也就是要放置这些类的包的全路径。    daoPackage 'tsou.com.simple.greendaoforkotlin.greendao'    //设置DaoMaster、DaoSession、Dao目录    targetGenDir 'src/main/java'}dependencies     compile 'org.greenrobot:greendao:3.2.0'}

• 在项目的build.gradle中

buildscript {    ext.kotlin_version = '1.1.50'    repositories {        mavenCentral()        google()        jcenter()    }    dependencies {        classpath 'com.android.tools.build:gradle:3.0.0-beta7'        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"        classpath 'org.greenrobot:greendao-gradle-plugin:3.2.0'        // NOTE: Do not place your application dependencies here; they belong        // in the individual module build.gradle files    }}

步骤二、创建Student实体类

package tsou.com.simple.greendaoforkotlin.bean;import android.support.annotation.Keep;import org.greenrobot.greendao.annotation.Entity;import org.greenrobot.greendao.annotation.Id;import org.greenrobot.greendao.annotation.Generated;@Entity(generateConstructors = false)    public class Student {          @Id        private Long id;          private String name;        private int age;          public Student() {          }          @Keep        public Student(String name, int age) {              this.name = name;              this.age = age;          }          public Student(Long id, String name, int age) {              this.id = id;              this.name = name;              this.age = age;          }          @Keep          public Long getId() {              return id;          }          @Keep          public void setId(Long id) {              this.id = id;          }          @Keep          public String getName() {              return name;          }          @Keep          public void setName(String name) {              this.name = name;          }          @Keep          public int getAge() {              return age;          }          @Keep          public void setAge(int age) {              this.age = age;          }          @Keep          @Override          public boolean equals(Object o) {              if (this == o) return true;              if (!(o instanceof Student)) return false;              Student student = (Student) o;              return name.equals(student.name);          }          @Keep          @Override          public int hashCode() {              return (int) (id ^ (id >>> 32));          }          @Keep          @Override          public String toString() {              return "Student{" +                      "id=" + id +                      ", name='" + name + '\'' +                      ", age=" + age +                      '}';          }      }

步骤三、修复一下工程，自动生成greendao包下的类（就是点击一下小锤子），你会自动生成greendao包中的类。

步骤四、开始使用，创建管理类

package tsou.com.simple.greendaoforkotlin.managerimport android.content.Contextimport android.database.sqlite.SQLiteDatabaseimport tsou.com.simple.greendaoforkotlin.greendao.DaoMasterimport tsou.com.simple.greendaoforkotlin.greendao.DaoSessionclass DbManager private constructor(mContext: Context) {    private val DB_NAME = "test.db"    private var mDevOpenHelper: DaoMaster.DevOpenHelper? = null    private var mDaoMaster: DaoMaster? = null    private var mDaoSession: DaoSession? = null    init {        // 初始化数据库信息        mDevOpenHelper = DaoMaster.DevOpenHelper(mContext, DB_NAME)        getDaoMaster(mContext)        getDaoSession(mContext)    }    companion object {        @Volatile        var instance: DbManager? = null        fun getInstance(mContext: Context): DbManager? {            if (instance == null) {                synchronized(DbManager::class) {                    if (instance == null) {                        instance = DbManager(mContext)                    }                }            }            return instance        }    }    /**     * 获取可读数据库     *     * @param context     * @return     */    fun getReadableDatabase(context: Context): SQLiteDatabase? {        if (null == mDevOpenHelper) {            getInstance(context)        }        return mDevOpenHelper?.getReadableDatabase()    }    /**     * 获取可写数据库     *     * @param context     * @return     */    fun getWritableDatabase(context: Context): SQLiteDatabase? {        if (null == mDevOpenHelper) {            getInstance(context)        }        return mDevOpenHelper?.getWritableDatabase()    }    /**     * 获取DaoMaster     *     * @param context     * @return     */    fun getDaoMaster(context: Context): DaoMaster? {        if (null == mDaoMaster) {            synchronized(DbManager::class.java) {                if (null == mDaoMaster) {                    mDaoMaster = DaoMaster(getWritableDatabase(context))                }            }        }        return mDaoMaster    }    /**     * 获取DaoSession     *     * @param context     * @return     */    fun getDaoSession(context: Context): DaoSession? {        if (null == mDaoSession) {            synchronized(DbManager::class.java) {                mDaoSession = getDaoMaster(context)?.newSession()            }        }        return mDaoSession    }}

步骤五、增删改查，

package tsou.com.simple.greendaoforkotlin.daoimport android.content.Contextimport tsou.com.simple.greendaoforkotlin.bean.Studentimport tsou.com.simple.greendaoforkotlin.greendao.StudentDaoimport tsou.com.simple.greendaoforkotlin.manager.DbManagerclass StudentDaoOpe private constructor() {    private object mHolder {        val instance = StudentDaoOpe()    }    companion object {        fun getInstance(): StudentDaoOpe {            return mHolder.instance        }    }    /**     * 添加数据至数据库     * @param context     * *     * @param stu     */    fun insertData(context: Context?, stu: Student) {        DbManager.getInstance(context!!)?.getDaoSession(context)?.getStudentDao()?.insert(stu)    }    /**     * 将数据实体通过事务添加至数据库     * @param context     * *     * @param list     */    fun insertData(context: Context?, list: List<Student>?) {        if (null == list || list.size <= 0) {            return        }        DbManager.getInstance(context!!)?.getDaoSession(context)?.getStudentDao()?.insertInTx(list)    }    /**     * 添加数据至数据库，如果存在，将原来的数据覆盖     * 内部代码判断了如果存在就update(entity);不存在就insert(entity)；     * @param context     * *     * @param student     */    fun saveData(context: Context?, student: Student) {        DbManager.getInstance(context!!)?.getDaoSession(context)?.getStudentDao()?.save(student)    }    /**     * 删除数据至数据库     * @param context     * *     * @param student 删除具体内容     */    fun deleteData(context: Context?, student: Student) {        DbManager.getInstance(context!!)?.getDaoSession(context)?.getStudentDao()?.delete(student)    }    /**     * 根据id删除数据至数据库     * @param context     * *     * @param id      删除具体内容     */    fun deleteByKeyData(context: Context?, id: Long) {        DbManager.getInstance(context!!)?.getDaoSession(context)?.getStudentDao()?.deleteByKey(id)    }    /**     * 删除全部数据     * @param context     */    fun deleteAllData(context: Context?) {        DbManager.getInstance(context!!)?.getDaoSession(context)?.getStudentDao()?.deleteAll()    }    /**     * 更新数据库     * @param context     * *     * @param student     */    fun updateData(context: Context?, student: Student) {        DbManager.getInstance(context!!)?.getDaoSession(context)?.getStudentDao()?.update(student)    }    /**     * 查询所有数据     * @param context     * *     * @return     */    fun queryAll(context: Context?): MutableList<Student>? {        val builder = DbManager.getInstance(context!!)?.getDaoSession(context)?.getStudentDao()?.queryBuilder()        return builder?.build()?.list()    }    /**     * 根据id，其他的字段类似     * @param context     * *     * @param id     * *     * @return     */    fun queryForId(context: Context?, id: Long): MutableList<Student>? {        val builder = DbManager.getInstance(context!!)?.getDaoSession(context)?.getStudentDao()?.queryBuilder()        /**         * 返回当前id的数据集合,当然where(这里面可以有多组，做为条件);         * 这里build.list()；与where(StudentDao.Properties.Id.eq(id)).list()结果是一样的；         * 在QueryBuilder类中list()方法return build().list();         */        // Query<Student> build = builder.where(StudentDao.Properties.Id.eq(id)).build();        // List<Student> list = build.list();        return builder?.where(StudentDao.Properties.Id.eq(id))?.list()    }}

步骤六、mainactivity布局

<?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"    tools:context=".MainActivity">    <LinearLayout        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:orientation="horizontal">        <Button            android:id="@+id/add"            android:layout_width="0dp"            android:layout_height="wrap_content"            android:layout_weight="1"            android:text="增" />        <Button            android:id="@+id/delete"            android:layout_width="0dp"            android:layout_height="wrap_content"            android:layout_weight="1"            android:text="删" />        <Button            android:id="@+id/updata"            android:layout_width="0dp"            android:layout_height="wrap_content"            android:layout_weight="1"            android:text="改" />        <Button            android:id="@+id/check"            android:layout_width="0dp"            android:layout_height="wrap_content"            android:layout_weight="1"            android:text="查" />    </LinearLayout>    <Button        android:id="@+id/deleteAll"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:layout_centerInParent="true"        android:layout_weight="1"        android:text="删除全部" />    <Button        android:id="@+id/check_id"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:layout_above="@id/deleteAll"        android:layout_centerInParent="true"        android:text="根据id查" /></RelativeLayout>

步骤七、mainActivity

package tsou.com.simple.greendaoforkotlinimport android.content.Contextimport android.os.Bundleimport android.support.v7.app.AppCompatActivityimport android.util.Logimport kotlinx.android.synthetic.main.activity_main.*import tsou.com.simple.greendaoforkotlin.bean.Studentimport tsou.com.simple.greendaoforkotlin.dao.StudentDaoOpeclass MainActivity : AppCompatActivity() {    private var mContext: Context? = null    private var student: Student? = null    override fun onCreate(savedInstanceState: Bundle?) {        super.onCreate(savedInstanceState)        setContentView(R.layout.activity_main)        mContext = this        initData()        initListener()    }    private var studentList = mutableListOf<Student>()    /**     * 初始化数据     */    private fun initData() {        for (i in 0..99) {            student = Student(i.toLong(), "huang" + i, 25)            studentList.add(student!!)//不为null        }    }    private fun initListener() {        /**         * 增         */        add.setOnClickListener {            StudentDaoOpe.getInstance().insertData(mContext, studentList)        }        /**         * 删         */        delete.setOnClickListener {            val student = Student(5.toLong(), "haung" + 5, 25)            /**             * 根据特定的对象删除             */            StudentDaoOpe.getInstance().deleteData(mContext, student)            /**             * 根据主键删除             */            StudentDaoOpe.getInstance().deleteByKeyData(mContext, 7)        }        /**         * 删除所有         */        deleteAll.setOnClickListener {            StudentDaoOpe.getInstance().deleteAllData(mContext)        }        /**         * 更新         */        updata.setOnClickListener {            val student = Student(2.toLong(), "haungxiaoguo", 16516)            StudentDaoOpe.getInstance().updateData(mContext, student)        }        /**         * 查询全部         */        check.setOnClickListener {            val students = StudentDaoOpe.getInstance().queryAll(mContext)            for (i in students!!.indices) {                Log.i("Log", students[i].name)            }        }        /**         * 根据id查询         */        check_id.setOnClickListener {            val students = StudentDaoOpe.getInstance().queryForId(mContext, 50)            for (i in students!!.indices) {                Log.i("Log", students[i].name)            }        }    }}

其他详细的步骤请看：greendao3.0以上使用步骤（一）：基础使用

Demo地址：http://download.csdn.net/download/huangxiaoguo1/10008298