Exercise

Validate that a user made a selection

Recall from the video that though it is often good practice to select a default value for your selector inputs, if one should be excluded, you can throw a custom error message to your users that clues them in on what they need to do for the app to run successfully.

We saw in the last exercise that, without a default value for the pickerInput(), the plot is simply blank. Instead of a blank plot, in this exercise you'll show users a custom error message telling them to make the correct selection needed to get the app working.

Instructions

100 XP

Add a custom error message that will display by default letting users know they should select an input for mental versus physical health.