Selection of charts in Shiny - r

Question

I am trying to create a simple Shiny app. My goal is to select one of the charts from the drop-down menu and visualization of the selected chart. Below you will see my script.
---
title: "Test App"
output:
flexdashboard::flex_dashboard:
orientation: columns
vertical_layout: fill
runtime: shiny
---
```{r setup, include=FALSE}
# Libraries ----
# App
library(flexdashboard)
library(shiny)
library(shinyjs)
library(shinyWidgets)
# Core
library(tidyverse)
library(tidyquant)
# Visualizations
library(ggplot2)
# Data
data=mtcars
data$cyl <- as.factor(data$cyl)
```
Column {.sidebar}
-----------------------------------------------------------------------
```{r}
useShinyjs(rmd = TRUE)
selectInput("clusterNum", label = h4("Charts"),
choices = list("Chart1" = "Chart1", "Chart2" = "Chart2"),
selected = "Chart1")
```
Column {data-width=650}
-----------------------------------------------------------------------
### Chart
```{r}
Chart1<-qplot(x = data$wt, y = data$mpg)
Chart2<-qplot(data$cyl, geom = "bar")
num <- reactive(input$clusterNum)
renderPlot(num())
```
When I run this script, I can change the names of the Charts (e.g., Chart1 or Chart2) from the drop-down menu, but I can't see a visualization of the selected chart. So can anybody help me how to solve this problem and to have a visualization as in the pic below?

Answer 1

You could use switch or an ìf-else inside your renderPlot to display the chosen chart.
Note: qplot was depcrecated in ggplot2 3.4.0 and will probably removed in the future. To take account of this I switched to ggplot().
---
title: "Test App"
output:
flexdashboard::flex_dashboard:
orientation: columns
vertical_layout: fill
runtime: shiny
---
```{r setup, include=FALSE}
library(flexdashboard)
library(shiny)
library(tidyverse)
# Data
data <- mtcars
data$cyl <- as.factor(data$cyl)
```
Column {.sidebar}
-----------------------------------------------------------------------
```{r}
selectInput("clusterNum",
label = h4("Charts"),
choices = list("Chart1" = "Chart1", "Chart2" = "Chart2"),
selected = "Chart1"
)
```
Column {data-width=650}
-----------------------------------------------------------------------
### Chart
```{r}
Chart1 <- ggplot(data, aes(x = wt, y = mpg)) +
geom_point()
Chart2 <- ggplot(data, aes(cyl)) +
geom_bar()
renderPlot({
switch(input$clusterNum,
"Chart1" = Chart1,
"Chart2" = Chart2
)
})
```