Flash on Update signals that chart data has changed by briefly overlaying a flash animation, drawing the user's attention to the chart whenever data is updated, added or removed.
Enabling Flash On Update Copy Link
Flash on Update is disabled by default. To enable it, set flashOnUpdate.enabled to true.
{
flashOnUpdate: {
enabled: true,
},
}
Category Flash Copy Link
Flashing just the category band makes it easier to identify which categories have changed. Set item to 'category' to enable this.
{
flashOnUpdate: {
enabled: true,
item: 'category',
},
}
In this example:
- Click 'Start Updates' to begin a simulated data feed that updates 1–3 bars every 2 seconds.
- Only the changed bars flash.
- Click Stop Updates to pause the feed.
- Category Flash is only available on Category, Grouped Category, Unit Time and Ordinal Time axes.
Adding and Removing Data Copy Link
Category flash is also triggered when a category is added to the chart. Removing a category does not trigger a flash.
In this example:
- Click 'Add Sector' to add a new sector to the chart — the new category flashes on arrival.
- Click 'Remove Sector' to remove the last sector — no flash occurs on removal.
- Click 'Update' to update values for one or two sectors and observe the category flash.
Customisation Copy Link
The appearance and timing of the flash effect can be customised.
{
flashOnUpdate: {
enabled: true,
fill: '#ffd6a5',
flashDuration: 300,
fadeOutDuration: 700,
},
}
In this example:
- Use the 'Fill', 'Flash' and 'Fade' controls to adjust the flash appearance.
fill— the fill colour of the flash overlay.flashDuration— how long (in milliseconds) the flash remains at full opacity before fading.fadeOutDuration— how long (in milliseconds) the fade-out takes.
- Click 'Start Updates' to begin a simulated live price feed and observe the flash with the current settings.
- Click 'Stop Updates' to pause the feed.
Animation Copy Link
Flash on Update disables Animation by default, as the two are rarely used together. If you do need both, explicitly set animation: { enabled: true }.
When both are enabled, the flashDuration and fadeOutDuration values are scaled to fit within the data update animation phases, so the actual timing may differ from the configured values. Their ratio still controls how the duration is split between the hold and fade stages.