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NavigationRail

A material widget that is meant to be displayed at the left or right of an app to navigate between a small number of views, typically between three and five.

Examples​

Live example

import flet as ft

def main(page: ft.Page):

    rail = ft.NavigationRail(
        selected_index=0,
        label_type=ft.NavigationRailLabelType.ALL,
        # extended=True,
        min_width=100,
        min_extended_width=400,
        leading=ft.FloatingActionButton(icon=ft.icons.CREATE, text="Add"),
        group_alignment=-0.9,
        destinations=[
            ft.NavigationRailDestination(
                icon=ft.icons.FAVORITE_BORDER, selected_icon=ft.icons.FAVORITE, label="First"
            ),
            ft.NavigationRailDestination(
                icon_content=ft.Icon(ft.icons.BOOKMARK_BORDER),
                selected_icon_content=ft.Icon(ft.icons.BOOKMARK),
                label="Second",
            ),
            ft.NavigationRailDestination(
                icon=ft.icons.SETTINGS_OUTLINED,
                selected_icon_content=ft.Icon(ft.icons.SETTINGS),
                label_content=ft.Text("Settings"),
            ),
        ],
        on_change=lambda e: print("Selected destination:", e.control.selected_index),
    )

    page.add(
        ft.Row(
            [
                rail,
                ft.VerticalDivider(width=1),
                ft.Column([ ft.Text("Body!")], alignment=ft.MainAxisAlignment.START, expand=True),
            ],
            expand=True,
        )
    )

ft.app(target=main)

bgcolor​

Sets the color of the Container that holds all of the NavigationRail's contents.

destinations​

Defines the appearance of the button items that are arrayed within the navigation rail.

The value must be a list of two or more NavigationRailDestination instances.

extended​

Indicates that the NavigationRail should be in the extended state.

The extended state has a wider rail container, and the labels are positioned next to the icons. min_extended_width can be used to set the minimum width of the rail when it is in this state.

The rail will implicitly animate between the extended and normal state.

If the rail is going to be in the extended state, then the label_type must be set to none.

The default value is False.

group_alignment​

The vertical alignment for the group of destinations within the rail.

The NavigationRailDestinations are grouped together with the trailing widget, between the leading widget and the bottom of the rail.

The value must be between -1.0 and 1.0.

If group_alignment is -1.0, then the items are aligned to the top. If group_alignment is 0.0, then the items are aligned to the center. If group_alignment is 1.0, then the items are aligned to the bottom.

The default is -1.0.

label_type​

Defines the layout and behavior of the labels for the default, unextended NavigationRail.

When a navigation rail is extended, the labels are always shown.

Property value is NavigationRailLabelType enum with the following values: NONE (default), ALL, SELECTED.

leading​

An optional leading control in the rail that is placed above the destinations.

Its location is not affected by group_alignment.

This is commonly a FloatingActionButton, but may also be a non-button, such as a logo.

min_extended_width​

The final width when the animation is complete for setting extended to True.

The default value is 256.

min_width​

The smallest possible width for the rail regardless of the destination's icon or label size.

The default is 72.

This value also defines the min width and min height of the destinations.

To make a compact rail, set this to 56 and use label_type='none'.

selected_index​

The index into destinations for the current selected NavigationRailDestination or None if no destination is selected.

trailing​

An optional trailing control in the rail that is placed below the destinations.

Its location is affected by group_alignment.

This is commonly a list of additional options or destinations that is usually only rendered when extended is True.

on_change​

Fires when selected destination changed.

icon​

The name of the icon of the destination.

icon_content​

The icon Control of the destination. Typically the icon is an Icon control. Used instead of icon property.

If selected_icon_content is provided, this will only be displayed when the destination is not selected.

To make the NavigationRail more accessible, consider choosing an icon with a stroked and filled version, such as icons.CLOUD and icons.CLOUD_QUEUE. The icon should be set to the stroked version and selected_icon to the filled version.

label​

label_content​

The label Control for the destination.

The label must be provided when used with the NavigationRail. When label_type='none', the label is still used for semantics, and may still be used if extended is True.

padding​

The amount of space to inset the destination item.

See Container.padding for more information about padding and possible values.

selected_icon​

The name of alternative icon displayed when this destination is selected.

selected_icon_content​

An alternative icon Control displayed when this destination is selected.

If this icon is not provided, the NavigationRail will display icon_content in either state.