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Exercise

Add a continent selector: select input

When there are many options to let the user choose from, radio buttons can take up a lot of space and may not be ideal. Select inputs—also called 'dropdown lists'—can also be used to ask the user to choose an option from a list of choices, but in a more compact way. With a select input, all the options appear in a scrollable list, so it can be used even if you have many choices.

Similar to radio buttons, select inputs also have choices and selected parameters. Additionally, select inputs have a multiple argument, which, when set to TRUE, allows the user to select more than one value.

The code for the Shiny app from the last exercise is provided with slight modifications.

Instructions

100 XP
  • Add a selectInput() to the UI with ID "continents" and a label of "Continents", with the default continent set to "Europe".
    • The choices in the list should be all the different continents that exist in the gapminder dataset.
    • Allow the user to select multiple continents simultaneously.
  • Add code to the server such that only data for the selected continent is shown, by subsetting the gapminder dataset (line 23).