Should be called by implementers of renderXXX
functions in order to mark
their return values as Shiny render functions, and to provide a hint to Shiny
regarding what UI function is most commonly used with this type of render
function. This can be used in R Markdown documents to create complete output
widgets out of just the render function.
markRenderFunction(
uiFunc,
renderFunc,
outputArgs = list(),
cacheHint = "auto",
cacheWriteHook = NULL,
cacheReadHook = NULL
)
Arguments
uiFunc |
A function that renders Shiny UI. Must take a single argument:
an output ID. |
renderFunc |
A function that is suitable for assigning to a Shiny output
slot. |
outputArgs |
A list of arguments to pass to the uiFunc . Render
functions should include outputArgs = list() in their own parameter list,
and pass through the value to markRenderFunction , to allow app authors to
customize outputs. (Currently, this is only supported for dynamically
generated UIs, such as those created by Shiny code snippets embedded in R
Markdown documents). |
cacheHint |
One of "auto" , FALSE , or some other information to
identify this instance for caching using bindCache() . If "auto" , it
will try to automatically infer caching information. If FALSE , do not
allow caching for the object. Some render functions (such as renderPlot)
contain internal state that makes them unsuitable for caching. |
cacheWriteHook |
Used if the render function is passed to bindCache() .
This is an optional callback function to invoke before saving the value
from the render function to the cache. This function must accept one
argument, the value returned from renderFunc , and should return the value
to store in the cache. |
cacheReadHook |
Used if the render function is passed to bindCache() .
This is an optional callback function to invoke after reading a value from
the cache (if there is a cache hit). The function will be passed one
argument, the value retrieved from the cache. This can be useful when some
side effect needs to occur for a render function to behave correctly. For
example, some render functions call createWebDependency() so that Shiny
is able to serve JS and CSS resources. |
Value
The renderFunc
function, with annotations.
See also