If you are a starter of shiny as me, this post may help your know some principle of shiny.

What is shiny?

• R based
• View as webpage hosted on servers
• give a request, show the result

Backgroud needed

• Almost R only

Why shiny?

• Entirely extensible
• Display your data in an interactive way

How shiny works?

• Reactive Programming

  When the input changes, the R code will run again to get a refresh. Shiny makes the connections among R, input and the the output on your screen by some communication tags. So you can just focused on R code and let shiny do the other things.

• server.R

  You need write your R code here to tell shiny run what when the inputs change. The R code need a input and output values.

• ui.R

  You need tell the app user where is the input/output box, which values of the input should be transfer to R code and which values of the output should be display on the webpage. You can also custome your UI of app here if you have writen some basic html pages.

• Render function in server.R

  Tell shiny the output values used in the app’s webpage. This function need to be re-ran when the input changes, so the render function must be assighed to a output values while contains the input values.

• RUN

  When you finish your server.R and ui.R, just runApp() and you will get the great webpage.

How to share your apps?

• Push your shiny code on the github or make a zip file, the user can run it locally use the runUrl,runGitHub or runGist in the shiny package.

• You can also build up a server with www connection and put your app there.

Learn more?

• Lessons
• Tutorial