How many fields can MySQL have

Today, in the technical discussion group, "Everything goes as it happens" students have a question when reading, how many fields can there be in a MySQL table?With this question in mind, we explored, and then went on to discuss the issue of single field length. 1. Official Document Description The content of the official document is a ...

Posted on Wed, 01 Apr 2020 22:54:26 -0400 by bftwofreak

On the response of two click events when checkboxes are nested in ListView

On the response of two click events when checkboxes are nested in ListView In the near future, the company's project needs to add the select all / deselect all function, and the project used the ListView+CheckBox scheme before, and kept the click event of ListView's item and the click event of CheckBox at the same time ...

Posted on Wed, 01 Apr 2020 21:23:56 -0400 by kristy7

Logback different business logs write different files

In real development, we often need to distinguish business logs and system logs for different collection. If logback is used as the log component, how can different logs be written to different files? logback.xml <?xml version="1.0" encoding="UTF-8"?> <configuration> <property name="LOG_HOME" value="${catalina.base}/logs"/&gt ...

Posted on Wed, 01 Apr 2020 19:57:57 -0400 by rudy.siregar

Android animation foundation transform animation case (2)

I've talked about blending transform Animation before. What I'm going to say here is to write an Animation set (we know that there is a set container in JAVA, and the characteristics of the set container are: 1. Disorder; 2. No repetitive elements. Set in Mathematics) is used to store multiple Animation objects. This is ...

Posted on Wed, 01 Apr 2020 18:33:23 -0400 by izy

Conquer python3 file operation

1. How to open the file w: the file is opened in write only mode, and the file is emptied. If the file is not modified, it is created directly. r: the file is also read-only and cannot be written. w +: the file is opened in write read mode, and the file is empty, writable and readable r +: the file is opened in read-write mode, readable and wri ...

Posted on Wed, 01 Apr 2020 15:29:22 -0400 by gigabyt3r

Practical application of filters (encoding, sensitive words, compression filters)

Article Directory Preface Coding filter Develop filters Enhance request object Sensitive Word Filter Compressed Resource Filter Enhanced response object Filter test Summary Preface The definition of filters and the simple use of filters have been preliminarily introduced in the previous chap ...

Posted on Wed, 01 Apr 2020 12:52:51 -0400 by newjsguy

android hands on to teach you how to develop launcher (I) (android studio version)

Android skips the boot interface, directly launches the software itself, Android makes its own desktop instead of the native desktop, Android develops its own desktop launcher, which is android's desktop application. Next, we will develop our own launcher to replace the default launcher of the system.How can we make ou ...

Posted on Wed, 01 Apr 2020 10:47:57 -0400 by Headwaters

On snake bar

SnackBar is a newly added control in Android Support Library 22.2.1. We can simply understand it as an enhanced version of Toast or a lightweight Dialog.   Characteristic: 1. The purpose of snackBar is the same as that of Toast, which is used to prompt the user for the results after operation. 2. When the snackBar is displayed, the position i ...

Posted on Wed, 01 Apr 2020 09:02:59 -0400 by napier_matt

Android animation foundation transform animation case (4)

   today I'll talk about activity switching animation. Activity switching animation refers to the animation of activity jump, which is divided into: one animation of activity exit and the other animation of activity entry. After Android 2.0, there is a way to achieve this effect - override pending transition ...

Posted on Wed, 01 Apr 2020 07:20:08 -0400 by sargus

The most detailed dynamic Toolbar development practice summary of the whole network, 99% of programmers are watching!

A comprehensive introduction to the use of Toolbar.Speaking of Toolbar, there may be a lot of developed children's shoes that are still unfamiliar. That's OK. Please look down. Initial knowledge of Toolbar Toolbar is a Material Design ing style navigation control that has been introduced since Android 5.0. Google highly recommends that you u ...

Posted on Wed, 01 Apr 2020 01:33:08 -0400 by ruiner17