Tutorial by Examples: le

A collection of commonly used function buttons represented in compact visual form. <ul role="toolbar"> <li><img alt="New" src="new.png"></li> <li><img alt="Open" src="open.png"></li> <li><i...

A contextual popup that displays a description for an element. <span aria-describedby="slopedesc">Slope</span> <div role="tooltip" id="slopedesc">y=mx+b</div> Typically, the tooltip would be hidden. Using JavaScript, the tooltip would be dis...

A type of list that may contain sub-level nested groups that can be collapsed and expanded. <ul role="tree"> <li role="treeitem"> Part 1 <ul> <li role="treeitem">Chapter 1</li> <li role="treeitem"&gt...

A grid whose rows can be expanded and collapsed in the same manner as for a tree.

An option item of a tree. This is an element within a tree that may be expanded or collapsed if it contains a sub-level group of treeitems. <ul role="tree"> <li role="treeitem"> Part 1 <ul> <li role="treeitem">Chapter 1</l...

import java.io.BufferedReader; import java.io.BufferedWriter; import java.io.IOException; import java.nio.charset.StandardCharsets; import java.nio.file.Files; import java.nio.file.Paths; public class ReadingUTF8TextFile { public static void main(String[] args) throws IOException { ...

import java.io.BufferedWriter; import java.io.IOException; import java.nio.charset.StandardCharsets; import java.nio.file.Files; import java.nio.file.Paths; public class WritingUTF8TextFile { public static void main(String[] args) throws IOException { //StandardCharsets is avail...

If you want to see the schema information of your table, you can use one of the following: SHOW CREATE TABLE child; -- Option 1 CREATE TABLE `child` ( `id` int(11) NOT NULL AUTO_INCREMENT, `fullName` varchar(100) NOT NULL, `myParent` int(11) NOT NULL, PRIMARY KEY (`id`), KEY `momm...

Query to create table on db CREATE TABLE `user` ( `id` smallint(5) unsigned NOT NULL AUTO_INCREMENT, `name` varchar(30) NOT NULL, `course` smallint(5) unsigned DEFAULT NULL, PRIMARY KEY (`id`) ) ENGINE=InnoDB; CREATE TABLE `course` ( `id` smallint(5) unsigned NOT NULL AUTO_INCREMENT, `nam...

Unlike other middleware functions error-handling middleware functions have four arguments instead of three: (err, req, res, next). Sample: app.use(function(err, req, res, next) { console.error(err.stack); res.status(500).send('Error found!'); });

Given a file sample: hello world ahello here hello_there A normal grep for "hello" returns: $ grep hello sample hello world ahello here hello_there Using -w allows to select those lines containing matches that form whole words: $ grep -w hello sample hello world

A module is an importable file containing definitions and statements. A module can be created by creating a .py file. # hello.py def say_hello(): print("Hello!") Functions in a module can be used by importing the module. For modules that you have made, they will need to be in t...

Suppose you have many changes in one or more files but from each file you only want to commit some of the changes, you can select the desired changes using: git add -p or git add -p [file] Each of your changes will be displayed individually, and for each change you will be prompted to choose...

A word of caution: AsyncTask has many gotcha's apart from the memory leak described here. So be careful with this API, or avoid it altogether if you don't fully understand the implications. There are many alternatives (Thread, EventBus, RxAndroid, etc). One common mistake with AsyncTask is to c...

when the object is deleted, delete all the objects in the association.

when the object is deleted, delete all the objects in the association. In addition to that, when an object is removed from the association and not associated with another object (orphaned), also delete it.

when an object is save/update/delete, check the associations and save/update/delete all the objects found. In additional to that, when an object is removed from the association and not associated with another object (orphaned), also delete it.

Directives, as the name suggests, are direction or instructions for the container to follow when translating a JSP to a servlet. There are 3 directives namely page, include and taglib which you can use in your JSP. Below is a simple example of using page directive: <%@ page isErrorPage="tr...

NOTE: In most cases, it is better to use a UIButton instead of making a UILabel you can tap on. Only use this example, if you are sure, that you don't want to use a UIButton for some reason. Create label Enable user interaction Add UITapGestureRecognizer The key to create a clickable UIL...

Leaflet is an open-source JavaScript library for making dynamic maps for the web. RStudio wrote R bindings for Leaflet, available through its leaflet package, built with htmlwidgets. Leaflet maps integrate well with the RMarkdown and Shiny ecosystems. The interface is piped, using a leaflet() funct...