Using a dynamic UI to draw a 3d plot in shiny - r

Question

I have a dataframe:
df1<-data.frame(a=rnorm(100),b=rnorm(100),c=rnorm(100),ID1=c("A","B"),ID2=(c("A","B","C","D")))
I am drawing a 3d plot with plotly by adding add_trace in a loop, like:
library(shiny)
library(plotly)
library(tidyverse)
df1<-data.frame(a=rnorm(100),b=rnorm(100),c=rnorm(100),ID1=c("A","B"),ID2=(c("A","B","C","D")))
test<-unique(df1$ID2)
tempt.col<-c("red","blue","green","yellow")
p<-plot_ly()
for(i in 1:length(test)){
df2<-df1[df1$ID2==test[i],] %>%
select(a,b,c)
p<-add_trace(p=p,
data = df2,
x=~a,y=~b,z=~c,
type="scatter3d",
marker = list(size=5,color=tempt.col[i]),
mode="markers"
)
}
p
It works very well like:
Now I want to achieve this in shiny, I would like to generate colourInput based on the length of the selected ID, the ui:
ui<-fluidPage(
fluidRow(
sidebarPanel(
selectInput("select1","Select the ID",choices = colnames(df1[,4:5]),multiple = FALSE),
actionButton("act1","Go"),
uiOutput("ui1"),
),
mainPanel(
tableOutput("table1"),
plotlyOutput("plot.3d",height = "1000px")
)
)
)
server:
server<-function(input,output){
tempt.group<-reactive({
unique(df1[,input$select1])
})
observeEvent(input$act1,{
tempt.vector<-list()
tempt.col.name<-isolate(
vector(mode = "list",length = 2)
)
for(i in 1:length(tempt.group())){
tempt.vector[[i]]<-colourpicker::colourInput(
inputId = paste0("ColorID",i),
label = tempt.group()[i])
tempt.col.name[[1]][i]<-paste0("ColorID",i)
tempt.col.name[[2]][i]<-tempt.group()[i]
}
output$ui1<-renderUI({
tempt.vector
})
names(tempt.col.name)<-c("inputId","label")
col.name<-reactive({
data.frame(sapply(tempt.col.name,cbind))
})
col.df<-reactive({
tempt.col.df<-reactiveValuesToList(input)
data.frame(
names = names(tempt.col.df[grepl("ColorID", names(tempt.col.df))]),
values = unlist(tempt.col.df[grepl("ColorID", names(tempt.col.df))], use.names = FALSE)
)
})
group.col.df<-reactive({
merge(col.df(),col.name(),by.x="names",by.y="inputId")
})
output$table1<-renderTable(
group.col.df()
)
pp<-reactive({
p<-plot_ly()
for(i in 1:length(tempt.group())){
# col<-group.col.df()[group.col.df()[,"label"]==tempt.group()[i],"values"] ####it should be something wrong with here
df2<-df1[df1$ID==tempt.group()[i],] %>%
select(a,b,c)
p<-add_trace(p=p,
data = df2,
x=~a,y=~b,z=~c,
type="scatter3d",
# marker = list(size=5,color=col[i]), ####it should be something wrong with here
mode="markers"
)
}
p
})
output$plot.3d<-renderPlotly({
pp()
})
})
}
shinyApp(ui=ui,server=server)
The app is like:
I want to fetch the colourInput and pass to the color of the 3d scatter plot, but nothing works. The page either keeps refreshing or frozen,
That must be something wrong with col<-group.col.df()[group.col.df()[,"label"]==tempt.group()[i],"values"] and marker = list(size=5,color=col[i]),
please help.

Answer 1

The below works as intended.
library(shiny)
library(plotly)
df1<-data.frame(a=rnorm(100),b=rnorm(100),c=rnorm(100),ID1=c("A","B"),ID2=(c("A","B","C","D")))
# Define UI
ui<-fluidPage(
fluidRow(
sidebarPanel(
selectInput("select1","Select the ID",choices = colnames(df1[,4:5]),multiple = FALSE),
# actionButton("act1","Go"),
uiOutput("myui"),
# keep track of the last selection on all selectInput created dynamically
),
mainPanel(
#tableOutput("table1"),
plotlyOutput("plot.3d",height = "1000px")
)
)
)
# Define server logic required to draw a histogram
server<-function(input,output){
rv <- reactiveValues(mygroup=0, uitaglist = list(), uilabels = list(), input_subset = list(), plotly=NULL)
observeEvent(input$select1, {
newgroup <- unique(df1[,input$select1])
rv$mygroup <- newgroup
# ui tags
rv$uitaglist <- list()
for(i in 1:length(rv$mygroup)){
rv$uitaglist[[i]]<-colourpicker::colourInput(
inputId = paste0("ColorID",i),
label = rv$mygroup[i])
rv$uilabels[[i]] <- paste0("ColorID",i)
}
})
output$myui <- renderUI({
rv$input_subset <- rv$uitaglist
})
observe({
rv$input_subset <- lapply(rv$uilabels, function(x) input[[x]])
p<-plot_ly()
for(i in 1:length(rv$mygroup)) {
df2<-df1[df1$ID2 == rv$mygroup[i],] %>% select(a,b,c)
p<-add_trace(p=p,
data = df2,
x=~a,y=~b,z=~c,
type="scatter3d",
marker = list(size=5,color=rv$input_subset[[i]]),
mode="markers"
)
}
rv$plotly <- p
})
output$plot.3d<-renderPlotly({
rv$plotly
})
} # end server
# Run the application
shinyApp(ui = ui, server = server)
The main difficulty was to observe all your dynamically-generated UI inputs at once. Turns out it could be done using observe and lapply.
Observing several inputs is problematic because the error Must use single string to index into reactivevalues is returned by trying to index input by a vector or list.
Now, Why this can't be done out-of-the-box is a good question.