一、配置：
1.在build.gradle（Project）中添加依赖
dependencies {
classpath 'org.greenrobot:greendao-gradle-plugin:3.2.1'
}
2.在build.gradle（Module）中添加依赖
apply plugin: 'org.greenrobot.greendao'
android{
//greendao配置
greendao {
//版本号，升级时可配置
schemaVersion 1
//dao创建的目录
daoPackage 'com.mcp1993.greendaodemo.dao'
targetGenDir 'src/main/java'
}
}
dependencies {
//greendao依赖
compile 'org.greenrobot:greendao:3.2.0'
}
二、使用
1.创建bean。
@Entity
public class Challenge_horData implements Serializable{
private static final long serialVersionUID =1L;
private String uniquekey;
private String title;
private String date;
private String category;
private String author_name;
private String url;
private String thumbnail_pic_s;
private String thumbnail_pic_s02;
private String thumbnail_pic_s03;
@Generated(hash = 134817119)
public Challenge_horData(String uniquekey, String title, String date, String category, String author_name, String url,
String thumbnail_pic_s, String thumbnail_pic_s02, String thumbnail_pic_s03) {
this.uniquekey = uniquekey;
this.title = title;
this.date = date;
this.category = category;
this.author_name = author_name;
this.url = url;
this.thumbnail_pic_s = thumbnail_pic_s;
this.thumbnail_pic_s02 = thumbnail_pic_s02;
this.thumbnail_pic_s03 = thumbnail_pic_s03;
}
@Generated(hash = 255457321)
public Challenge_horData() {
}
public String getUniquekey() {
return uniquekey;
}
public void setUniquekey(String uniquekey) {
this.uniquekey = uniquekey;
}
public String getTitle() {
return title;
}
public void setTitle(String title) {
this.title = title;
}
public String getDate() {
return date;
}
public void setDate(String date) {
this.date = date;
}
public String getCategory() {
return category;
}
public void setCategory(String category) {
this.category = category;
}
public String getAuthor_name() {
return author_name;
}
public void setAuthor_name(String author_name) {
this.author_name = author_name;
}
public String getUrl() {
return url;
}
public void setUrl(String url) {
this.url = url;
}
public String getThumbnail_pic_s() {
return thumbnail_pic_s;
}
public void setThumbnail_pic_s(String thumbnail_pic_s) {
this.thumbnail_pic_s = thumbnail_pic_s;
}
public String getThumbnail_pic_s02() {
return thumbnail_pic_s02;
}
public void setThumbnail_pic_s02(String thumbnail_pic_s02) {
this.thumbnail_pic_s02 = thumbnail_pic_s02;
}
public String getThumbnail_pic_s03() {
return thumbnail_pic_s03;
}
public void setThumbnail_pic_s03(String thumbnail_pic_s03) {
this.thumbnail_pic_s03 = thumbnail_pic_s03;
}
}
然后rebuild project,就会自动生成：
![YFP2O]2O}VBCDV24)9IK$DP.png](http://upload-images.jianshu.io/upload_images/2261176-a2539a7b24340e08.png?imageMogr2/auto-orient/strip%7CimageView2/2/w/1240)]
这里记录一下注解：
@Entity：告诉GreenDao该对象为实体，只有被@Entity注释的Bean类才能被dao类操作
@Id：对象的Id，必须使用Long类型作为EntityId，否则会报错。(autoincrement = true)表示主键会自增，如果false就会使用旧值
@Property：可以自定义字段名，注意外键不能使用该属性
@NotNull：属性不能为空
@Transient：使用该注释的属性不会被存入数据库的字段中
@Unique：该属性值必须在数据库中是唯一值
@Generated：编译后自动生成的构造函数、方法等的注释，提示构造函数、方法等不能被修改
2.在Application初始化greendao数据库。
public class APP extends Application{
public static DaoSession mDaoSession;
@Override
public void onCreate() {
super.onCreate();
initGreenDao();//初始化greendao数据库
}
private void initGreenDao() {
//DevOpenHelper每次数据库升级会清空数据，一般用于开发
DaoMaster.DevOpenHelper helper = new DaoMaster.DevOpenHelper(this,"geendao_db",null);
Database db = helper.getWritableDb();
mDaoSession = new DaoMaster(db).newSession();
}
public static DaoSession getDaoSession(){
return mDaoSession;
}
DevOpenHelper：创建SQLite数据库的SQLiteOpenHelper的具体实现
DaoMaster：GreenDao的顶级对象，作为数据库对象、用于创建表和删除表
DaoSession：管理所有的Dao对象，Dao对象中存在着增删改查等API
3.在activity中使用。
加载数据
//读缓存,判断数据库是否为空，网络状态
if (null != APP.getDaoSession().getChallenge_horDataDao().loadAll()
&& 0 <APP.getDaoSession().getChallenge_horDataDao().loadAll().size()
&& !NetworkUtil.isAvailable(MainActivity.this)){
datas.clear();//清空集合，为了保险起见
datas.addAll(APP.getDaoSession().getChallenge_horDataDao().loadAll());
mAdapter = new HorRecyclerAdapter(datas, MainActivity.this);
recy_clerview.setAdapter(mAdapter);
recy_clerview.addOnItemTouchListener(new RecyclerView.SimpleOnItemTouchListener(){
@Override
public void onTouchEvent(RecyclerView rv, MotionEvent e) {
super.onTouchEvent(rv, e);
}
});
mAdapter.setOnItemClickListener(this);
}else {
//加载网络数据
loadData();
}
数据获取成功后添加到数据库
//将数据插入数据库，插入数据的时候用到Lambda表达式
Observable.from(datas).subscribeOn(Schedulers.io()).subscribe(challenge_horData -> {
//避免插入重复数据的逻辑
count = APP.getDaoSession().getChallenge_horDataDao().queryBuilder().where(Challenge_horDataDao.Properties.Uniquekey.eq(challenge_horData.getUniquekey())).count();
if (count == 0){
APP.getDaoSession().getChallenge_horDataDao().insertOrReplaceInTx(challenge_horData);
}else {
//刷新操作，清除bean，插入数据
APP.getDaoSession().getChallenge_horDataDao().deleteAll();
APP.getDaoSession().getChallenge_horDataDao().insertOrReplaceInTx(challenge_horData);
}
});
demo代码
an example
