Hover Event Data

Mix.install([
  {:plotly_ex, "~> 0.3"},
  {:kino, "~> 0.18"}
])

Section

plotly_hover fires when the cursor enters a data point's hover region. The event payload contains a "points" list — same structure as click events.

alias Plotly.{Figure, Scatter}
alias Plotly.Kino.PlotlyLive

chart =
  Figure.new()
  |> Figure.add_trace(Scatter.new(
    x: [1, 2, 3, 4, 5],
    y: [10, 15, 13, 17, 12],
    mode: "lines+markers",
    marker: %{size: 10}
  ))
  |> Figure.update_layout(title: "Hover over points")
  |> PlotlyLive.new()

PlotlyLive.subscribe(chart, :hover_data, :hover)
chart

# Hover over the chart above, then run this cell
receive do
  {:hover_data, event} ->
    IO.inspect(event, label: "hover event", pretty: true)
after
  10_000 -> "No hover within 10 s"
end