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Create a streaming widget

Source: R/stream-viz.R
stream_viz.Rd

Creates a multi-channel signal viewer widget that fetches its data from the binary stream file produced by stream_to_js.

Usage

stream_viz(
  outputId,
  session = shiny::getDefaultReactiveDomain(),
  stream_id = NULL,
  width = NULL,
  height = NULL,
  refresh_rate = 33,
  show_controls = TRUE,
  streaming = FALSE,
  token = NULL
)

Arguments

outputId

Character scalar. The output ID matching the corresponding streamVizOutput call. Used to compute stream_id automatically when stream_id is NULL.

session

Shiny session object. Defaults to the active reactive domain. Together with outputId determines the token-qualified stream file identifier.

stream_id

Character scalar or NULL. When NULL (default) the stream identifier is computed as stream_file_id(outputId, session, token = token). Provide an explicit value to override for non-Shiny or advanced use.

width, height

Widget dimensions (passed to createWidget).

refresh_rate

Numeric scalar (milliseconds). Polling interval used when the viewer is in active streaming mode (play button pressed). Lower values give smoother animation but increase CPU/network load. Default 33 (approximately 30 Hz).

show_controls

Logical. Whether to display the hover toolbar (play/pause, zoom, reset, export). Default TRUE.

streaming

Logical. Whether to start active streaming immediately when the widget is rendered. Default FALSE; set to TRUE to begin polling for new data automatically. Can also be toggled later via updateStreamViz.

token

Character scalar or NULL. When NULL (default) the session's own token is used. Override with a parent session token when running inside a standalone viewer (pop-out window) so that the child session fetches the parent's binary stream file.

Value

An htmlwidgets object.

Details

The outputId together with session is used to auto-compute the token-qualified stream file identifier via stream_file_id. You can override this by passing an explicit stream_id.

Use updateStreamViz for in-place updates without recreating the widget.

See also

streamVizOutput, renderStreamViz, updateStreamViz, stream_file_id