A good tooltip briefly describes unlabeled controls or provides a bit of additional information about labeled controls, when this is useful. It can also help customers navigate the UI by offering additional—not redundant—information about control labels, icons, and links. A tooltip should always add valuable information; use sparingly.

There are two components you can use to display a tooltip:

• Tooltip: A styled tooltip that you can display on a chosen target.

• TooltipHost: A wrapper that automatically shows a tooltip when the wrapped element is hovered or focused.

For more details and examples visit the official docs. The R package can not handle each and every case, so for advanced use cases you need to work using the original docs to achieve the desired result.

TooltipHost(...)

## Arguments

className

string
Class name to apply to the tooltip itself, not the host. To apply a class to the host, use hostClassName or styles.root.

closeDelay

number
Number of milliseconds to delay closing the tooltip, so that the user has time to hover over the tooltip and interact with it. Hovering over the tooltip will count as hovering over the host, so that the tooltip will stay open if the user is actively interacting with it.

hostClassName

string
Class name to apply to tooltip host.

id

string
Optional ID to pass through to the tooltip (not used on the host itself). Auto-generated if not provided.

onTooltipToggle

onTooltipToggle?(isTooltipVisible: boolean): void;
Notifies when tooltip becomes visible or hidden, whatever the trigger was.

overflowMode

TooltipOverflowMode
If this is unset (the default), the tooltip is always shown even if there's no overflow.

If set, only show the tooltip if the specified element (Self or Parent) has overflow. When set to Parent, the parent element is also used as the tooltip's target element.

Note that even with Self mode, the TooltipHost does not check whether any children have overflow.

boolean
Whether or not to mark the TooltipHost root element as described by the tooltip. If not specified, the caller should pass an id to the TooltipHost (to be passed through to the Tooltip) and mark the appropriate element as aria-describedby the id.

tooltipProps

ITooltipProps
Additional properties to pass through for Tooltip.

calloutProps

ICalloutProps
Properties to pass through for Callout.

componentRef

IRefObject<ITooltip>
Optional callback to access the ITooltip interface. Use this instead of ref for accessing the public methods and properties of the component.

content

string | JSX.Element | JSX.Element[]
Content to be passed to the tooltip

delay

TooltipDelay
Length of delay. Set to TooltipDelay.zero if you do not want a delay.

directionalHint

DirectionalHint
How the tooltip should be anchored to its targetElement.

directionalHintForRTL

DirectionalHint
How the element should be positioned in RTL layouts. If not specified, a mirror of directionalHint will be used instead

maxWidth

string | null
Max width of tooltip

onRenderContent

IRenderFunction<ITooltipProps>
Render function to populate tooltip content.

styles

IStyleFunctionOrObject<ITooltipStyleProps, ITooltipStyles>
Call to provide customized styling that will layer on top of the variant rules.

targetElement

HTMLElement
Element to anchor the Tooltip to.

theme

ITheme
Theme provided by higher-order component.

## Best practices

### Content

• Don’t use a tooltip to restate a button name that’s already shown in the UI.

• When a control or UI element is unlabeled, use a simple, descriptive noun phrase. For example: “Highlighting pen”. Only capitalize the first word (unless a subsequent word is a proper noun), and don’t use a period.

• For a disabled control that could use an explanation, provide a brief description of the state in which the control will be enabled. For example: “This feature is available for line charts.”

• Only use periods for complete sentences.

For a UI label that needs some explanation:

• Briefly describe what you can do with the UI element.

• Use the imperative verb form. For example, "Find text in this file" (not "Finds text in this file").

• Don't include end punctuation unless there is at least one complete sentence.

For a truncated label or a label that’s likely to truncate in some languages:

• Provide the untruncated label in the tooltip.

• Don't provide a tooltip if the untruncated info is provided elsewhere on the page or flow.

• Optional: On another line, provide a clarifying description, but only if needed.

## Examples

library(shiny.fluent)

if (interactive()) {
shinyApp(
ui = TooltipHost(
content = "This is the tooltip content",
delay = 0,
Text("Hover over me")
),
server = function(input, output) {}
)
}