Fresh themes

{fresh} allow to create custom themes to use in {shiny} applications, currently you can create themes to use with:

Create a theme

Use function create_theme to create a new theme, this function accept variables to set specific parameters of the theme. There’s 3 type of variables depending on which framework you use:

bs_vars_* to create a shiny theme
adminlte_* to create a shinydashboard theme
bs4dash_* to create a bs4Dash theme

When using bs_vars_*, you can specify theme argument to use a Bootswatch template.

create_theme(
  theme = "default",
  bs_vars_button(
    default_color = "#FFF",
    default_bg = "#112446",
    default_border = "#112446",
    border_radius_base = "15px"
  ),
  bs_vars_wells(
    bg = "#FFF",
    border = "#112446"
  )
)

Here we modify shiny::actionButton appearance with bs_vars_button and appearance of shiny::sidebarPanel with bs_vars_wells.

Result looks like :

Use a theme

There’s two way to use a newly created theme :

inline in the UI (useful to quickly visualize your theme)
using a CSS file (recommended)

Inline

Don’t specify an output file and use result of create_theme() in use_theme() directly in your application :

mytheme <- create_theme(
  theme = "default",
  bs_vars_navbar(
    default_bg = "#75b8d1",
    default_color = "#FFFFFF",
    default_link_color = "#FFFFFF",
    default_link_active_color = "#75b8d1",
    default_link_active_bg = "#FFFFFF",
    default_link_hover_color = "firebrick"
  ),
  output_file = NULL
)

navbarPage(
  title = "Custom navbar",
  header = tagList(
    use_theme(mytheme) # <-- use your theme
  ),
  tabPanel("Tab 1"),
  tabPanel("Tab 2")
)

File

When you create a theme, you can specify an output file :

create_theme(
  theme = "default", 
  ...,
  output_file = "my-custom-theme.css"
)

Put the file my-custom-theme.css in the www/ folder of your application, and reference it like that in your UI’s fluidPage or navbarPage :

fluidPage(
  
  theme = "my-custom-theme.css",
  
  # ...
)

# or if using a navbar page
navbarPage(
  
  title = "My application",
  theme = "mytheme.css",
  
  # ...
)

In {shinydashboard} or {bs4Dash}, you can use use_theme() with a path inside dashboardBody or bs4DashBody :

dashboardBody(
  use_theme("path/to/theme.css")
)

bs4DashBody(
  use_theme("path/to/theme.css")
)

Note that the path must be in the www/ folder of your application.