Chart Layouts
Selecting between the single-chart, Index + Call/Put, and Call + Put layouts.
Every chart mounted via the default NxtChartPage constructor can switch between three
layouts, chosen by the user at runtime from the chart's own Layout settings tab — there
is no separate constructor or route for this.
The three layouts
| Layout | Shows | Requires an option chain |
|---|---|---|
| Single Chart | One chart for the primary symbol | No |
| Index + Call/Put | The underlying chart plus its ATM CE/PE strikes side by side | Yes |
| Call + Put | ATM CE and PE strikes side by side, no underlying chart | Yes |
The right-panel ATM strikes come from the same atmSymbols and chartTopOptions your
ChartInterface implementation already provides — see
atmSymbols and
chartTopOptions. Nothing about that data
contract changed; only how a user reaches a two-panel layout did.
Availability
Index + Call/Put and Call + Put are only offered when the current symbol has an option
chain (i.e. optionSymbols resolves to a non-empty list for it). For a symbol with no
option chain, the Layout tab only shows Single Chart, and the chart always renders as a
single chart regardless of a previously-saved preference.
Persistence
The chosen layout is saved automatically and restored on the next launch — see
Chart Persistence. Unlike everything else on that page,
this one preference is not scoped to your storageKey: it's a single global setting
shared across every symbol and user on the same device/installation.
See NxtChartPage for how to mount the chart, and Trading for wire formats.