GreenDao集成与使用

GreenDao源码分析

GreenDao升级数据库原有数据

1. 整个项目添加依赖：

buildscript {
    repositories {
        google()
        jcenter()
        mavenCentral() // add repository
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:3.3.2'
        classpath 'org.greenrobot:greendao-gradle-plugin:3.2.2' // add plugin
        // NOTE: Do not place your application dependencies here; they belong
        // in the individual module build.gradle files
    }
}

2. app 模块添加依赖

apply plugin: 'org.greenrobot.greendao' // apply plugin
android {
	greendao {
    	schemaVersion 1//数据库版本
	}
}
dependencies {
	implementation 'org.greenrobot:greendao:3.2.2' // add library
}

3. 写数据库实体类

//class名字Note为表名
@Entity
public class Note {
    @Id
    private Long id;
    @NotNull
    private String text;
    @Generated(hash = 990389247)//自动生成的，下一步的时候会自动生成
    public Note(Long id, @NotNull String text) {
        this.id = id;
        this.text = text;
    }
    @Generated(hash = 1272611929)//自动生成的，下一步的时候会自动生成
    public Note() {
    }
    ...get/set...
}

4. Build->Make Project:
   
5. 配置application（注意在清单配置中替换）

public class App extends Application {
    private DaoSession daoSession;
    @Override
    public void onCreate() {
        super.onCreate();
        //设置数据库名
        DaoMaster.DevOpenHelper helper = new DaoMaster.DevOpenHelper(this,"test1");
        Database db = helper.getWritableDb();
        daoSession = new DaoMaster(db).newSession();
    }
    public DaoSession getDaoSession() {
        return daoSession;
    }
}

6. 向数据库添加数据

public class MainActivity extends AppCompatActivity {
   DaoSession daoSession;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        DaoSession daoSession =((App)getApplication()).getDaoSession();
        new Thread(new Runnable() {
            @Override
            public void run() {
                Note note = new Note();
                note.setText("aaa");
                daoSession.insert(note);
                handler.sendEmptyMessage(0);
            }
        }).start();

    }
    @SuppressLint("HandlerLeak")
    Handler handler = new Handler(){
        @Override
        public void handleMessage(Message msg) {
            switch (msg.what){
                case 0:
                    List<Note> list = daoSession.loadAll(Note.class);
                    for(Note note:list)Log.w("打印",note.getText());
                    break;
            }
        }
    };
}

打印结果：

2019-04-17 18:13:23.831 24612-24612/yang.shuai.mydagger W/打印: aaa