SEARCH KEYWORD -- EVENT MECHANISM



  JavaScript finite state machine

Finite state machine is a very useful design model, it can be used to simulate many events in the world. In short, finite state machine has three features: Number of states is finite At any moment, one object can only be in one state In some condition, it will transfer from one state to another state In JavaScript, finite state machine can be applied in many places. For example, one menu element on a webpage. When the mouse hovers on the menu, the menu will show up, while the mouse moves away...

   JavaScript,Finite state machine,State     2013-09-02 11:00:57

  Loading images progressively using Gaussian blur

The popular online publishing platform Medium has adopted an impressive image loading mechanism -- pure color - blur image loading - real image loading. Since images on Medium usually have high definition, it takes much time to load an image and hence brings a bad user experience if rendering the image after it's completely downloaded. The solution Medium comes out is to preload an small image when the real image is being loaded.  On Medium, the HTML code will have below pattern ...

   JAVASCRIPT,ALGORITHM,GAUSSIAN BLUR,MEDIUM,BLUR IMAGE     2016-09-25 03:33:00

  Extension context menu is missing in Firefox after restart

If you have experience of writing Chrome extension, you may be familiar with how you can add a context menu for your extension. The code would be similar to below: chrome.runtime.onInstalled.addListener(function() { chrome.contextMenus.removeAll(); chrome.contextMenus.create({ "id": "your_id", "title": "Your Title", "contexts": ["all"] }); }); You need to add a listener listening to the extension install event. Once the extension is installed, create a contex...

   CHROME,FIREFOX,EXTENSION,CONTEXT MENU     2018-11-16 20:58:20

  Understand this in JavaScript

In JavaScript, this is always pointing to the owner of a function or a method. Function Let's check out function first. function introduce() {      alert("Hello, I am Laruence\r\n"); } For this function, what does this point to? In JavaScript, a global function's owner is the current page, i.e, the window object. Because its a method of the window object if we define a global function. Now you should know the this will point to the window object in the above function. ...

   JavaScript,this,event,call     2013-04-03 04:10:03

  How to make select in WinSock exceed the 64-socket limit

When doing cross-platform network programming, the only API available on Windows that corresponds to the epoll/kevent style reactor event model is select. However, it has a limitation: the number of sockets passed into select cannot exceed FD_SETSIZE, which is set to 64. Therefore, select in Java’s NIO on Windows also has the same limit. Many services ported to Windows that use the reactor model face this constraint, which often gives the impression that server programs on Windows hav...

   EXCEED,SELECT,JAVA,WINDOWS     2024-10-31 23:47:50

  How to play with cross domain request

What is cross domain request In simple, cross domain request is to request resource from other domain in one domain. Note, the "other domain" doesn't just mean domain name only, it includes much more. If the protocol, domain name, port is not the same, two domains will be considered different.  Below example describes what is considered as different domain. http://www.a.com/a.jshttp://www.a.com/b.js               # Same domainhttp://www.a.com/lab/a.js &nb...

   FRONT END,JSONP,CROSS DOMAIN,CROSS ORIGIN,CORS,DOCUMENT.DOMAIN,WINDOW.NAME     2016-11-06 00:48:54

  Content based HTTP Cache

Browsers may cache the webpages we visited, when user types a URL on the address bar, the browser may cache the webpage returned from server while displaying it. If there is no update on the webpage, then next time when the browser requests the same page, it will not download the page again, instead it will load the cached page. If the website explicitly specify that the page is updated, then the browser will download the page again from the server. What's HTTP Cache? You may be familiar with th...

   HTTP Cache,Web crawler     2013-05-24 05:12:59

  Windows 8 launch event data

Today on Microsoft Windows 8 launch event, Microsoft CEO Steve Ballmer and Windows manager Steven Sinofsky shared with us some data. Let's see what's happening to Windows. Since launch, Windows 7 system gains a total of 670 million upgrade and 400 million new PC installed with Windows 7.Microsoft's cloud storage service Skydrive, 200 million users share 11 billion photos and 550 million documents. new 2PB file uploaded monthly.(1PB = 1024TB)Windows 8 has been tested in 190 countries for 1.24 bil...

   Windows 8,Microsoft data     2012-10-25 13:16:30

  Google open sources Leak Finder for JavaScript

Google recently open sourced a tools for finding memory leaks in JavaScript programs. In JavaScript you cannot have "memory leaks" in the traditional sense, but you can have objects which are unintentionally kept alive and which in turn keep alive other objects, e.g., large parts of DOM. Leak Finder for JavaScript works against the Developer tools remote inspecting protocol of Chrome, retrieves heap snapshots, and detects objects which are "memory leaks" according to a given leak definition. The...

   Google,Open source,JavaScript     2012-08-15 13:45:34

  JavaScript efficiency catch up

JavaScript is a very flexible language, we can write JavaScript code freely with various styles, different kinds of codes will have different execution efficiency. Here we summarize some tips we get from our development. Efficiency of JavaScript itself JavaScript has execution context chain, closures, prototype inheritance, eval etc. It brings us some magic features, but it also introduces the performance issue, if we don't use them properly, it will affect the codes execution efficiency. 1. Glo...

   JavaScript,efficiency,event delegation,eval     2013-04-02 04:08:46