greendao的基本操作

1.先配置项目的builder.gradle

// Top-level build file where you can add configuration options common to all sub-projects/modules.

buildscript {

    repositories {

        google()

        jcenter()

    }

    dependencies {

        classpath 'com.android.tools.build:gradle:3.0.0'

        classpath 'org.greenrobot:greendao-gradle-plugin:3.0.0'

        // NOTE: Do not place your application dependencies here; they belong

        // in the individual module build.gradle files

    }

}

allprojects {

    repositories {

        google()

        jcenter()

    }

}

task clean(type: Delete) {

    delete rootProject.buildDir

}

2.配置module.app的builder.gradle

apply plugin: 'com.android.application'

apply plugin: 'org.greenrobot.greendao'

android {

    compileSdkVersion

    defaultConfig {

        applicationId "com.lingdangmao.demo_zidingyi_textview"

        minSdkVersion

        targetSdkVersion

        versionCode

        versionName "1.0"

        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"

    }

    buildTypes {

        release {

            minifyEnabled false

            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'

        }

    }

}

dependencies {

    implementation fileTree(dir: 'libs', include: ['*.jar'])

    implementation 'com.android.support:appcompat-v7:26.1.0'

    implementation 'com.android.support.constraint:constraint-layout:1.0.2'

    testImplementation 'junit:junit:4.12'

    androidTestImplementation 'com.android.support.test:runner:1.0.1'

    androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.1'

    //greendao

    api 'org.greenrobot:greendao:3.0.1'

    api 'org.greenrobot:greendao-generator:3.0.0'

}

greendao {

    schemaVersion

    daoPackage 'com.anye.greendao.gen'

    targetGenDir 'src/main/java'

}

3.创建一个用户的实例类,创建完之后，编译一下，会自动生成文件

@Entity

public class User {

    @Id

    private Long id;

    private String name;

}

4.编写myapplication类继承application

public class MyApplication extends Application {

    private DaoMaster.DevOpenHelper mHelper;

    private SQLiteDatabase db;

    private DaoMaster mDaoMaster;

    private DaoSession mDaoSession;

    public static MyApplication instance;

    public static MyApplication getInstance(){

        return instance;

    }

    @Override

    public void onCreate() {

        super.onCreate();

        instance =this;

        setDataBase();

    }

    private void setDataBase(){

        mHelper = new DaoMaster.DevOpenHelper(this, "notes-db", null);

        db = mHelper.getWritableDatabase();

        // 注意：该数据库连接属于 DaoMaster，所以多个 Session 指的是相同的数据库连接。

        mDaoMaster = new DaoMaster(db);

        mDaoSession = mDaoMaster.newSession();

    }

    public DaoSession getmDaoSession() {

        return mDaoSession;

    }

    public SQLiteDatabase getDb() {

        return db;

    }

}

5.在activity中操作

//根据条件查询

        UserDao mUserdao = MyApplication.getInstance().getmDaoSession().getUserDao();

        Query<User> query =  mUserdao.queryBuilder().where(UserDao.Properties.Id.eq()).build();

        User u= query.unique();  //没有就是null

        Log.d(TAG, "onCreate11: "+u);

        Log.d(TAG, "onCreate11: "+u.getId());

        Log.d(TAG, "onCreate11: "+u.getName());

        //添加

        User mUser=new User((long),"mike");

        //mUserdao.insert(mUser);

        //删除

        //long id= 2;

        //mUserdao.deleteByKey(id);

        //改

        mUser = new User((long),"anye0803");

        mUserdao.update(mUser);

        //查询

        List<User> users = mUserdao.loadAll();

        for(int i=;i<users.size();i++){

            Log.d(TAG, "onCreate: "+users.get(i).getId());

            Log.d(TAG, "onCreate: 1"+users.get(i).getName());

        }

完成，上面是最基本的，实际开发中用到再看