Calculating sum in Shiny - r

Question

I'm trying to create a shiny app as a practice planner where users can select which drills they are going to do and how long they will do each drill and the app then shows them the total meters covered for the whole practice. Now I'm trying to calculate the total values of meters covered during a session based on the drills selected and the number of minutes selected for each drill. However my total is always equal to 0 even though it works for calculating each drill separately. Could someone help me figure out what I'm doing wrong please. Below is my code with sample data.
library(shiny)
library(dplyr)
# MyData <- read.csv("/Users/sonamoravcikova/Desktop/ShinyTest/ForShiny1.csv")
MyData <- structure(list(Drill = c("GP Warm Up", "5v2 Rondo", "11v11", "10v6 Drop
Behind Ball"), PlayerLoadPerMinute = c(7.72949670665213, 6.49382926701571,
9.67483408668731, 5.86770863636364), MetersPerMinute = c(69.9524820610687,
45.823744973822, 95.9405092879257, 58.185375), class = "data.frame", row.names
= c(NA, -4L)))
# Define UI ----
ui <- fluidPage(
titlePanel("Practice Planner"),
sidebarLayout(
sidebarPanel(
#Select number of drills
numericInput("num", h3("Number of Drills"), value = 1),
textOutput("MpM_Total")
),
mainPanel(
#Show boxes for the number of drill selected and select drill type
selectInput("DrillName1",
label = "Choose a Drill:",
choices = unique(MyData$Drill),
selected = NULL,
multiple = FALSE),
sliderInput("slider1",
label = h3("Slider"),
min = 0,
max = 60,
value = 0),
textOutput("MpM1"),
br(),
conditionalPanel(
condition = "input.num > '1'",
selectInput("DrillName2",
label = "Choose a Drill:",
choices = unique(MyData$Drill),
selected = NULL,
multiple = FALSE),
sliderInput("slider2",
label = h3("Slider"),
min = 0,
max = 60,
value = 0),
textOutput("MpM2")),
br(),
conditionalPanel(
condition = "input.num > '2'",
selectInput("DrillName3",
label = "Choose a Drill:",
choices = unique(MyData$Drill),
selected = NULL,
multiple = FALSE),
sliderInput("slider3",
label = h3("Slider"),
min = 0,
max = 60,
value = 0),
textOutput("MpM3"))
)
)
)
# Define server logic ----
server <- function(input, output, session) {
#Calculate number of meters covered
lapply(1:10, function(x) {
MetersPerMin <- reactive({
chosendrill <- input[[paste0("DrillName",x)]]
MpM <- MyData %>%
distinct(MetersPerMinute, .keep_all = T)
MpM_text <- (MpM$MetersPerMinute[MpM$Drill == chosendrill]) * (input[[paste0("slider",x)]])
})
output[[paste0("MpM", x)]] <- renderText({
paste0("Meters covered: ", MetersPerMin())
})
MpM_Sum <- reactive({
sum(MetersPerMin())
})
output$MpM_Total <- renderText({
paste("Total Meters Covered", MpM_Sum())
})
})
}
# Create Shiny app ----
shinyApp(ui = ui, server = server)

Answer 1

library(shiny)
library(dplyr)
MyData <- data.frame(Drill = c('GP Warm Up', '5v2 Rondo', '11v11', '10v6 Drop Behind Ball'),
PlayerLoadPerMinute = c(7.72949670665213, 6.49382926701571, 9.67483408668731, 5.86770863636364),
MetersPerMinute = c(69.9524820610687, 45.823744973822, 95.9405092879257, 58.185375))
MpM <- MyData %>%
distinct(MetersPerMinute, .keep_all = T)
# Define UI ----
ui <- fluidPage(
titlePanel('Practice Planner'),
sidebarLayout(
sidebarPanel(
#Select number of drills
numericInput('num', h3('Number of Drills'), value = 1),
textOutput('MpM_Total')
),
mainPanel(
#Show boxes for the number of drill selected and select drill type
selectInput('DrillName1',
label = 'Choose a Drill:',
choices = unique(MyData$Drill),
selected = NULL,
multiple = FALSE),
sliderInput('slider1',
label = h3('Slider'),
min = 0,
max = 60,
value = 0),
textOutput('MpM1'),
br(),
conditionalPanel(
condition = 'input.num > "1"',
selectInput('DrillName2',
label = 'Choose a Drill:',
choices = unique(MyData$Drill),
selected = NULL,
multiple = FALSE),
sliderInput('slider2',
label = h3('Slider'),
min = 0,
max = 60,
value = 0),
textOutput('MpM2')
),
br(),
conditionalPanel(
condition = 'input.num > "2"',
selectInput('DrillName3',
label = 'Choose a Drill:',
choices = unique(MyData$Drill),
selected = NULL,
multiple = FALSE),
sliderInput('slider3',
label = h3('Slider'),
min = 0,
max = 60,
value = 0),
textOutput('MpM3')
)
)
)
)
# Define server logic ----
server <- function(input, output, session) {
MetersPerMin <- reactive({
idx <- input$num
if (idx < 1) {
idx <- 1
} else if (idx > 3) {
idx <- 3
}
mpms <- sapply(1:idx, function(x) {
chosendrill <- input[[ paste0('DrillName', x) ]]
mpm <- (MpM$MetersPerMinute[ MpM$Drill == chosendrill ]) * (input[[ paste0('slider', x) ]])
output[[ paste0('MpM', x) ]] <- renderText(paste0('Meters covered: ', mpm))
mpm
})
mpms
})
output$MpM_Total <- renderText({
paste('Total Meters Covered', sum(MetersPerMin()))
})
}
# Create Shiny app ----
shinyApp(ui = ui, server = server)