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* - Convert all example apps to single file app.R file - Make relevant updates to Readmes to match up with app.R structure - Add color to plots (RStudio blue) - In 04_mpg example: Show outliers by default, as opposed to hide, since this is more routine - In 06_tabsets and 08_html examples: Don't name random data vector "data" - Add extensive comments to app.R files and use consistent formatting of comments across examples - In 09_upload example: Use req() to check for NULL entry * add news entry summarizing changes * use true RStudio blue, #75AADB * Conver shinyApp calls at the end to drop argument name in examples 3-11, except for the custom HTML example. Kept them in for examples 1&2 for completeness in first exporuse to function. * Pull news items that got added before this PR was merged * Update comment for shinyApp function -- it creates an app object, doesn't run the app
This example demonstrates a core feature of Shiny: reactivity. In the server function, a reactive called datasetInput is declared.
Notice that the reactive expression depends on the input expression input$dataset, and that it's used by two output expressions: output$summary and output$view. Try changing the dataset (using Choose a dataset) while looking at the reactive and then at the outputs; you will see first the reactive and then its dependencies flash.
Notice also that the reactive expression doesn't just update whenever anything changes--only the inputs it depends on will trigger an update. Change the "Caption" field and notice how only the output$caption expression is re-evaluated; the reactive and its dependents are left alone.