GreenDao数据库

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使用步骤:
  • 1 配置gradle相关
Project(根目录)的build.gradle下:缺什么补什么不知道怎么加的自己琢磨吧...

    buildscript {    repositories {        jcenter()        mavenCentral()    }    dependencies {        classpath 'com.android.tools.build:gradle:2.3.3'        classpath 'org.greenrobot:greendao-gradle-plugin:3.2.1'        // NOTE: Do not place your application dependencies here; they belong        // in the individual module build.gradle files    }}


实体类存在自身Module的build.gradle下:


apply plugin: 'org.greenrobot.greendao'// 添加应用依赖插件android {    /*针对greenDao的一些配置*/    greendao {        schemaVersion 1 //数据库版本号        daoPackage 'com.usher.greendao_demo.greendao.gen' //自动生成的工具类的包名        targetGenDir 'src/main/java' //路径    }}dependencies {   。。。。其他依赖    /*greenDao框架*/    compile 'org.greenrobot:greendao:3.2.0'}


先写好实体类User

public class User {    @Id    private long id;    private String name;    @Generated(hash = 586692638)    public User() {    }    @Generated(hash = 1144922831)    public User(long id, String name) {        this.id = id;        this.name = name;    }    public long getId() {        return id;    }    public void setId(long id) {        this.id = id;    }    public String getName() {        return name;    }    public void setName(String name) {        this.name = name;    }}


greenDao多使用注解,如果你要将某一实体存储到数据库中,需要先对实体进行编写。
@Entity表明该类是持久化的类【持久化含义,存入数据库文件中,作本地化处理】
@Id选择一个long或Long类型的属性作为该实体所对应数据库中数据表的主键【类型要是long】
@Generated写在构造方法前
将以上注解写好后,点击AS上的Make Project即可
然后可以发现,你的Module中多了个包,点开可以看到如下



然后接下来就可以对数据库进行操作了
先上布局文件:

<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    android:layout_width="match_parent"    android:layout_height="match_parent"    android:orientation="vertical">    <TextView        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:layout_gravity="center_horizontal"        android:layout_margin="10dp"        android:text="greenDao lib test"        android:textColor="@android:color/black" />    <EditText        android:id="@+id/etId"        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:hint="请输入用户id"        android:inputType="number"        android:textSize="15sp" />    <EditText        android:id="@+id/etName"        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:hint="请输入用户名"        android:textSize="15sp" />    <Button        android:id="@+id/btnAdd"        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:text="新增" />    <Button        android:id="@+id/btnDelete"        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:text="删除" />    <Button        android:id="@+id/btnQuery"        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:text="查询" />    <TextView        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:layout_gravity="center_horizontal"        android:layout_margin="10dp"        android:text="查询结果"        android:textColor="@android:color/black" />    <TextView        android:id="@+id/tvQuery"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:layout_gravity="center_horizontal"        android:layout_margin="10dp"        android:textColor="@android:color/black" /></LinearLayout>



然后是MainActivity:

public class MainActivity extends AppCompatActivity {    UserDao userDao;    private EditText etId;    private EditText etName;    private Button btnAdd;    private Button btnDelete;    private Button btnQuery;    private TextView tvQuery;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        initView();        initDbHelp();        /*新增一条数据*/        btnAdd.setOnClickListener(new View.OnClickListener() {            @Override            public void onClick(View view) {                String id = etId.getText().toString();                String name = etName.getText().toString();                if (isNotEmpty(id) && isNotEmpty(name)) {                    QueryBuilder qb = userDao.queryBuilder();                    ArrayList<User> list = (ArrayList<User>) qb.where(UserDao.Properties.Id.eq(id)).list();                    if (list.size() > 0) {                        Toast.makeText(MainActivity.this, "主键重复", Toast.LENGTH_SHORT).show();                    } else {                        userDao.insert(new User(Long.valueOf(id), name));                        Toast.makeText(MainActivity.this, "插入数据成功", Toast.LENGTH_SHORT).show();                    }                } else {                    if (isEmpty(id) && isNotEmpty(name)) {                        Toast.makeText(MainActivity.this, "id为空", Toast.LENGTH_SHORT).show();                    }                    if (isEmpty(name) && isNotEmpty(id)) {                        Toast.makeText(MainActivity.this, "姓名为空", Toast.LENGTH_SHORT).show();                    }                    if (isEmpty(id) && isEmpty(name)) {                        Toast.makeText(MainActivity.this, "请填写信息", Toast.LENGTH_SHORT).show();                    }                }                etId.setText("");                etName.setText("");            }        });        /*删除指定数据*/        btnDelete.setOnClickListener(new View.OnClickListener() {            @Override            public void onClick(View view) {                String id = etId.getText().toString();                if (isNotEmpty(id)) {                    userDao.deleteByKey(Long.valueOf(id));                    QueryBuilder qb = userDao.queryBuilder();                    ArrayList<User> list = (ArrayList<User>) qb.where(UserDao.Properties.Id.eq(id)).list();                    if (list.size() < 1) {                        Toast.makeText(MainActivity.this, "删除数据成功", Toast.LENGTH_SHORT).show();                        etId.setText("");                        etName.setText("");                    }                } else {                    Toast.makeText(MainActivity.this, "id为空", Toast.LENGTH_SHORT).show();                }            }        });        /*查询数据*/        btnQuery.setOnClickListener(new View.OnClickListener() {            @Override            public void onClick(View view) {                String id = etId.getText().toString();                if (isNotEmpty(id)) {                    QueryBuilder qb = userDao.queryBuilder();                    ArrayList<User> list = (ArrayList<User>) qb.where(UserDao.Properties.Id.eq(id)).list();                    if (list.size() > 0) {                        String text = "";                        for (User user : list) {                            text = text + "\r\n" + user.getName();                        }                        tvQuery.setText(text);                    } else {                        tvQuery.setText("");                        Toast.makeText(MainActivity.this, "不存在该数据", Toast.LENGTH_SHORT).show();                    }                    etId.setText("");                    etName.setText("");                } else {                    Toast.makeText(MainActivity.this, "id为空", Toast.LENGTH_SHORT).show();                }            }        });    }    /*初始化数据库相关*/    private void initDbHelp() {        DaoMaster.DevOpenHelper helper = new DaoMaster.DevOpenHelper(this, "recluse-db", null);        SQLiteDatabase db = helper.getWritableDatabase();        DaoMaster daoMaster = new DaoMaster(db);        DaoSession daoSession = daoMaster.newSession();        userDao = daoSession.getUserDao();    }    private void initView() {        etId = (EditText) findViewById(R.id.etId);        etName = (EditText) findViewById(R.id.etName);        btnAdd = (Button) findViewById(R.id.btnAdd);        btnDelete = (Button) findViewById(R.id.btnDelete);        btnQuery = (Button) findViewById(R.id.btnQuery);        tvQuery = (TextView) findViewById(R.id.tvQuery);    }    private boolean isNotEmpty(String s) {        if (s != null && !s.equals("") || s.length() > 0) {            return true;        } else {            return false;        }    }    private boolean isEmpty(String s) {        if (isNotEmpty(s)) {            return false;        } else {            return true;        }    }}


以上有一些判断是否成功的操作,因为greenDao并没有提供操作后的回调,所以我这里就只是手动判断一下
依次存入1/usher 、2/tom、3/harry 三组数据,然后提取数据库文件如下:

OK大功告成!
想要更深入的了解呢,请访问以下网址
http://www.apkbus.com/blog-904057-67980.html
http://www.jianshu.com/p/00d93c2d511f
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