elevation property Null safety

The z-coordinate of this BottomNavigationBar.

If null, defaults to 8.0.

The z-coordinate at which to place this material relative to its parent.

This controls the size of the shadow below the material and the opacity of the elevation overlay color if it is applied.

If this is non-zero, the contents of the material are clipped, because the widget conceptually defines an independent printed piece of material.

Defaults to 0. Changing this value will cause the shadow and the elevation overlay or surface tint to animate over Material.animationDuration.

The value is non-negative.

See also:

• ThemeData.useMaterial3 which defines whether a surface tint or elevation overlay is used to indicate elevation.
• ThemeData.applyElevationOverlayColor which controls the whether an overlay color will be applied to indicate elevation.
• Material.color which may have an elevation overlay applied.
• Material.shadowColor which will be used for the color of a drop shadow.
• Material.surfaceTintColor which will be used as the overlay tint to show elevation.