I think that before jumping into what the input$ list is, it's a good idea to quickly define what reactivity is and show a small example. This could help make the rest of the concept a bit clearer to people who have never heard of this before.
I suggest making the first slide in lesson 5 as follows:
Reactivity 101
x <- 5
y <- x + 1
x <- 10
# What is y? 6 or 11?
Show this slide, talk about how in R we are used to thinking that in this code, when x changes y is unaffected. Then say that if x and y are reactive variables, then y reacts to x changing and gets updated as well, so in a reactive world, such as shiny, y would now be 11. This is what reactivity means in a very broad simplification.
If you don't like this idea, feel free to ignore :)
I think that before jumping into what the input$ list is, it's a good idea to quickly define what reactivity is and show a small example. This could help make the rest of the concept a bit clearer to people who have never heard of this before.
I suggest making the first slide in lesson 5 as follows:
Reactivity 101
When value of variable x changes, anything that relies on x is re-evaluated
Contrast with regular R:
Show this slide, talk about how in R we are used to thinking that in this code, when x changes y is unaffected. Then say that if x and y are reactive variables, then y reacts to x changing and gets updated as well, so in a reactive world, such as shiny, y would now be 11. This is what reactivity means in a very broad simplification.
If you don't like this idea, feel free to ignore :)