NoCoffee

NoCoffee插件简介

NoCoffee插件描述

Vision problems are me pervasive than most of us realize. Upwards of 285 million people wldwide are visually impaired. Many me have low  moderate visual difficulties. The number in the U.S. is expected to double by 2020, due to the aging of the baby boomer generation.

NoCoffee can be helpful f understing the problems faced by people with slight to extreme vision problems, such as:

* Low Acuity: Some web pages use very small text  click targets. While it’s true that users use builtin browser zoom  screen magnifiers like ZoomText (http://www.aisquared.com/zoomtext/), many nontechnical users do not know how.
* Low Contrast Sensitivity: Many designers use text with very low contrast, e.g. light gray text on white. Incidentally, here are some great tools f analyzing contrast on the web,  my favite is the Snook Colour Contrast Check at http://snook.ca/technical/colour_contrast/colour.html.
* Colblindness: Although col use in design is definitely a good thing, it’s imptant to remember the maxim “do not rely on col alone”, as 710% of males have some fm of colblindness. Chris Campbell has a great article describing colrelated design problems  solutions. See http://www.particletree.com/features/interfacescolblindness/.
* Visual snow, glare, ghosting  cataracts.
* Nystagmus (rapid, involuntary, oscillaty movement of the eyes).
* Obstructed visual field: floaters, obstruction to one side (retinal detachment  hemanopia), obstructed central vision (glaucoma), spotty vision (diabetic retinopathy)  obstructed peripheral vision (retinitis pigmentosa  macular degeneration). Note: the simulations of partial visual fields cannot follow your eye gaze as they would in the real wld.

As always, feedback appreciated!
                                

NoCoffee插件离线安装方法

1.首先用户点击谷歌浏览器右上角的自定义及控制按钮，在下拉框中选择设置。

2.在打开的谷歌浏览器的扩展管理器最左侧选择扩展程序或直接输入：chrome://extensions/

3.找到自己已经下载好的Chrome离线安装文件xxx.crx，然后将其从资源管理器中拖动到Chrome的扩展管理界面中，这时候用户会发现在扩展管理器的中央部分中会多出一个”拖动以安装“的插件按钮。

4.下载 NoCoffeeChrome插件v0.4.9版本到本地。

5.勾选开发者模式，点击加载已解压的扩展程序，将文件夹选择即可安装插件。

注意：最新版本的chrome浏览器直接拖放安装时会出现“程序包无效CRX-HEADER-INVALID”的报错信息，参照这篇文章即可解决