Getting started with the leancloud-data storage feature

Recently doing a simple mobile work scheduler, where the data section uses the data storage capabilities provided by Leancloud. Sort out some of the code and share it with you.

Avobject Add a record

Some of the code looks like this:

    Private StaticFinal String TABLENAME ="Project";//Create a new record with the database table named Project     Public Static void CreateProject(String name) {Final AvobjectObject=NewAvobject (TABLENAME);Object. put ("Name", name);Object. put ("CreateDate",NewDate (). GetTime ());Object. put ("CreateAccount", User.getusername ());Object. put ("Createname", User.getstring ("Name"));Object. put ("Membernum",0);Object. put ("Tasknum",0);Object. put ("State",1); Savecallback callback =NewSavecallback () {@Override Public void  Done(Avexception e) {PostInfo (Object, e);        }        }; Saveproject (Object, callback); }

• The record appears in the project table
• Savecallback is the asynchronous callback after a successful save, and when the E in the done (avexception e) is null, the Save succeeds

Query a record

    /***     * 根据id查询记录     */    privatestaticvoidgetProject(String id, GetCallback callback) {        new AVQuery<AVObject>(TABLENAME);        query.getInBackground(id, callback);    }

• Getcallback is an asynchronous callback after a successful query, the method to be implemented is done (Avobject Avobject, avexception e)

Querying more than one record

 /*** * get multiple records, sort by creation time */ public  static  void  getallproject         () {avquery<avobject> query = new  avquery<> (TABLENAME);        Query.orderbydescending ( "createat" ); Query.findinbackground (new  findcallback<avobject> () { @Override  public  void             Span class= "Hljs-title" >done  (list<avobject> list, avexception e) {postinfolist (list, E);    }        }); }

• Findcallback for asynchronous callbacks after successful query, the method to be implemented is done (list< avobject > List, avexception E)

Modify a single record

     Public Static void Addtasknum(String ID) {Getcallback Getcallback =NewGetcallback<avobject> () {@Override             Public void  Done(FinalAvobject Avobject, avexception e) {if(E = =NULL) {Avobject.put ("Tasknum", Avobject.getint ("Tasknum") +1); Savecallback Savecallback =NewSavecallback () {@Override                         Public void  Done(Avexception e) {if(E! =NULL) {//Exception handling}                        }                    };//Update to get the latest valueAvobject.setfetchwhensave (true);                Avobject.saveinbackground (Savecallback); }Else{//Exception handling}            }        };    Getproject (ID, getcallback); }

• Get a single Record object based on ID query first
• Updates a numeric value of the object, which is then saved, savecallback the asynchronous callback after the save succeeds
• Avobject.setfetchwhensave (true); indicates that when the update succeeds, the individual fields of the Avobject are the newest values

Avuser

In addition to the normal object Avobject, the Avuser object is provided to implement a simple user system, and the additional functionality is as follows

Registered

 /*** * Create a user account */ pu Blic  static  void  createuser  (final  string account, final  String Password, String Email, String name) {final  avuser user = new  Avuser (); User.setusername (account); User.setpassword (password); User.setemail (Email); User.put ( "name" , name); User.signupinbackground (new  signupcallback () {pub Lic  void  done  (avexception e) {  //Logic Processing }}); }

• Avuser supported information in addition to custom fields, there are username (account number), Password (password) and email (email)
• Signupcallback an asynchronous callback operation after a successful registration

Login

  /***     * 登录     */    publicstaticvoidLogin(String account, String password) {        new LogInCallback<AVUser>() {            @Override            publicvoiddone(AVUser user, AVException e) {                //逻辑处理            }        });    }

• Logincallback asynchronous callback for login success
• account, password, respectively, corresponding to the user's username and password

Gets the currently logged on user object

     /***     * 得到当前用户     *     * @return 当前用户     */    publicstaticgetCurrentUser() {        AVUser currentUser = AVUser.getCurrentUser();        return currentUser;    }

Cancellation

publicstaticvoidlogOut() {        AVUser.logOut(); }

Change Password

/***     * 修改密码     */    publicstaticvoidchangePwd(String old_password, String new_password) {        AVUser user = getCurrentUser();        ifnull) {            new UpdatePasswordCallback() {                @Override                publicvoiddone(AVException e) {                    //逻辑处理                }            });        }    }

Copyright NOTICE: This article for Bo Master original article, without Bo Master permission not reproduced.

Getting started with leancloud-data storage