Flexdashboard in R

Flexdashboard is a package for building dashboards with R using the flexbox layout. It is built on top of the R Markdown and Shiny frameworks, which allows for the integration of code, visualizations, and user input.

Installation

To install the flexdashboard package, use the following command:

install.packages("flexdashboard")

Building a Dashboard

Flexdashboard allows for the creation of simple to complex dashboards. To get started, create a new R Markdown file using the "Flex Dashboard" document type:

---
title: "My Dashboard"
output: 
  flexdashboard::flex_dashboard:
    orientation: rows
---

The orientation parameter determines whether the dashboard should be arranged in rows or columns.

In the body of the document, flexdashboard uses a combination of markdown, html and R code chunks to build the dashboard.

The markdown syntax is used to create static text and headings. For example:

## My Dashboard

Welcome to my dashboard. This dashboard will provide insight into my data analysis.

The html syntax is used to create interactive elements such as plots and tables. For example:

```{r}
library(ggplot2)

ggplot(mtcars, aes(x = disp, y = hp)) +
  geom_point()

The `R code chunk` syntax is used to execute R code and display the results. For example:

library(dplyr)

# Counting the number of observations in a dataset
nrow(mtcars)

## Layout and Appearance

Flexdashboard provides several built-in layout templates that can be customized. Additionally, it allows for full customization of the layout using CSS.

Templates can be set in the YAML header of the R Markdown file. For example:

title: "My Dashboard" output: flexdashboard::flex_dashboard: orientation: rows theme: flatly

The `theme` parameter specifies the style of the dashboard. 

Custom CSS can be added in a separate CSS file and linked to the R Markdown file. For example:

title: "My Dashboard" output: flexdashboard::flex_dashboard: orientation: rows css: styles.css

## Dashboards with Shiny

Flexdashboard can also be used in conjunction with Shiny to create dashboards that allow for user input and reactive output.

To include Shiny elements in a flexdashboard, add a `runtime: shiny` parameter to the YAML header. For example:

title: "My Dashboard" output: flexdashboard::flex_dashboard: orientation: rows runtime: shiny

Then, add Shiny code to create input elements and reactive output. For example:

library(shiny)

selectInput(inputId = "variable",
            label = "Select a variable:",
            choices = names(mtcars))
            
renderPlot({
  ggplot(mtcars, aes_string(x = input$variable, y = "hp")) +
    geom_point()
})

Overall, flexdashboard provides a powerful tool for creating dynamic and interactive dashboards in R. With easy-to-use templates and the ability to fully customize layouts, it is a great option for data visualization and reporting.