Introduction Here's a simple example of working with a reactive R6 in a shiny app. It is inspired by a post to RStudio Community (https://community.rstudio.com/t/good-way-to-create-a-reactive-aware-r6-class/84890) and uses the code provided by Winston Chang to create an R6 class that is reactive. The example code is …

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This is an initial concept of a framework for multiwindow shiny apps. Shiny is a great R package for building an interactive, web-based, graphical UI using R. It does, however, suffer from some limitations. One of these is the fact that a Shiny app runs in a single browser window. To make a more complex interface we …

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Generally there is no issue in sending a list of parameters (reactive and non-reactive) to a shiny module. Here's an example where a shiny module would be called multiple times, programatically, where the reactive nature of the parameters may be variable (reactive in one instance but not in another). One way to deal …

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Examples of passing a list of reactives, reactiveValues list and reactiveValues to a shiny module. This helps explain reactivity when passing values to a shiny module. In each case we pass a value A which triggers mod A and value B which triggers mod B. The code below and output demonstrates which outputs in the shiny …

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Here's a short shiny app along with some css that allows a font-awesome icon to behave as a checkbox. The font-weight setting in the css file determines if the icon should be solid (font-weight = 900 for TRUE) or regular (font-weight = 400 for FALSE). checkbox.css 1.fancy-checkbox input[type="checkbox"] { 2 …

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I work with a single server and hence cannot set up a dev, test, prod environment. We also cannot use CI/CD and so I've developed a particular way of working under these constraints. All code is stored under a codes folder, residing under the home folder. The folder structure of the app is shown below and subfolders …

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The sendSweetAlert function from the shinyWidgets package is a great way to communicate behavior to an end-user. As of version 0.4.9 shinyWidgets now uses SweetAlert2 which is no longer compatible with Internet Explorer thus breaking historical apps which use this feature. This is due to the fact that IE does not …

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Using parseQueryString in conjunction with session$clientData$url_search can be used to pass variables to a shiny app from the url address. It can also be used with Sys.getenv('SHINY_PORT') to follow programming paths based on variable values and execution environment. In the example below, the code points to different …

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Sometimes it's useful to mimic a button press in a shiny app when the Enter key is pressed, for example when entering a password. This has been documented before and works well for most situations but fails when the button widget is housed within renderUI. Here's an alternative that works wherever the password input …

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I have to post this for my own sanity. I tend to create shiny apps in a specific folder and link to them using symbolic links from the ShinyApp folder. This allows multiple versions (prod and dev) and keeps code clean. I don't know how many times I've wrestled with an app pointing to an earlier version when updates …

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