Android review 09 [content provider, music player]

catalog PersonCp PersonCp.java insert() ContentObserver music player 1. Add read-write permission 1.1. Dynamic permission granting (calling encapsulated methods) 2. Get music files( MainActivity.java ) 2, Music.java (entity class) Apply for access to SD card Set adapter Drop down refresh PersonCp PersonCp.java package cn.wang ...

Posted by jack_indigo on Sun, 31 May 2020 06:46:28 +0200

C ා data operation series - 17 Dapper ADO.NET ORM of the same race

0. Preface The previous four articles introduced an excellent framework SqlSugar developed by domestic developers, which gave us a bright feeling in front of our eyes. In this article, we will try another ORM framework, Dapper, which has a relatively high audience rating. Dapper is a lightweight ORM framework, which is characterized by high spe ...

Posted by hip_hop_x on Wed, 27 May 2020 05:53:48 +0200

Using SQLAlchemy in flask

In flask, many people prefer to operate the database through SQLAlchemy. In this case, it is recommended to use package instead of module to split the data model into a separate module. Such an approach is not necessary, but more reasonable. Flask-SQLAlchemy Extension Because SQLAlchemy is a general database abstracti ...

Posted by rahulephp on Fri, 01 May 2020 09:57:19 +0200

Common skills of Python Django REST framework

Conditional filtering Common filtration Example Interface usage Multilevel list get find default non ID Different api versions are not used Browse times Filter current user Multi parameter use Conditional filtering Common filtration _exact equals like 'aaa' __iexact is exactly the same as ig ...

Posted by cmccomas on Thu, 02 Apr 2020 06:27:41 +0200

FMDB database upgrade - add table fields

Reprinted from: https://www.jianshu.com/p/124a2e4e8c42 Preface Upgrading the database is a very tedious and seemingly troublesome thing. In an interview, the interviewer asked about adding fields to update the database and upgrading it. I replied that I could make a database migration copyEvery time I judge the updat ...

Posted by kalinkap on Mon, 30 Mar 2020 22:49:24 +0200

Android's local data store (SQLite database)

Article directory I. concept 1, understand 2. Application scenario 2, Database operations 1. Create database 2. Data operation (add, delete, modify and query) 2.1 add statement Method 1: Method 2: 2.2 delete statement 2.3 UPDATE statement 2.4 query statement 3. Import of mobile database file ...

Posted by flash gordon on Tue, 25 Feb 2020 12:51:55 +0100

Code generator

Talk about the code generator, some technical solutions, details Interface Overview Checklist Code structure Generic code target In order to simplify the code and generate template code, we have code generator. premise The premise of code generator is that there are already some templated and standardized code. Such as general DAO layer, S ...

Posted by cfemocha on Tue, 07 Jan 2020 02:41:56 +0100

Content provider of four Android application components

understand First, let's talk about why there is a ContentProvider? When an application wants to access the database of another application, because each application's database file is private and cannot be accessed directly, the accessed application needs an external database content provider, that is, content provider. &l ...

Posted by xxxxxx on Sat, 21 Dec 2019 22:30:36 +0100

Detailed usage of SQLite

Strongly Recommend Articles: Welcome to CollectionAndroid Dry Goods Sharing Read for five minutes, ten o'clock a day, and study with you for life. Here's Android, a programmer. This article mainly introduces some knowledge points in Android development. By reading this article, you will gain the following contents: Inheriting SQLiteOpenHelp ...

Posted by lillyapps on Tue, 06 Aug 2019 11:27:59 +0200

PyQt5 Quick Start PyQt5 Database Operation

Quick Start for PyQt5 (8) PyQt5 database operations 1. SQLite database 1. Introduction to SQLite SQLite is a lightweight database that implements a self-contained, server-free, zero-configuration, transactional SQL database engine, mainly used as a database for mobile applications and small desktop applications.Official website:https://www.sql ...

Posted by dubrubru on Mon, 29 Jul 2019 01:11:47 +0200