CupertinoAppBar

Examples

Live example

Basic Example

import flet as ft


def main(page: ft.Page):
    page.theme_mode = ft.ThemeMode.LIGHT

    page.appbar = ft.CupertinoAppBar(
        leading=ft.Icon(ft.Icons.PALETTE, color=ft.Colors.ON_SECONDARY),
        title=ft.Text("CupertinoAppBar Example"),
        trailing=ft.Icon(ft.Icons.WB_SUNNY_OUTLINED, color=ft.Colors.ON_SECONDARY),
        automatic_background_visibility=False,
        bgcolor=ft.Colors.SECONDARY,
        brightness=ft.Brightness.LIGHT,
    )

    page.add(ft.Text("Body!"))


ft.run(main)

App bar with theme mode toggle

import flet as ft


def main(page: ft.Page):
    page.theme_mode = ft.ThemeMode.LIGHT

    def handle_theme_mode_toggle(e: ft.Event[ft.IconButton]):
        page.theme_mode = (
            ft.ThemeMode.DARK
            if page.theme_mode == ft.ThemeMode.LIGHT
            else ft.ThemeMode.LIGHT
        )
        theme_mode_button.icon = (
            ft.Icons.WB_SUNNY_OUTLINED
            if page.theme_mode == ft.ThemeMode.LIGHT
            else ft.Icons.WB_SUNNY
        )
        page.update()

    theme_mode_button = ft.IconButton(
        icon=(
            ft.Icons.WB_SUNNY_OUTLINED
            if page.theme_mode == ft.ThemeMode.LIGHT
            else ft.Icons.WB_SUNNY
        ),
        icon_color=ft.Colors.ON_INVERSE_SURFACE,
        on_click=handle_theme_mode_toggle,
    )

    page.appbar = ft.CupertinoAppBar(
        automatic_background_visibility=False,
        leading=ft.Icon(ft.Icons.PALETTE, color=ft.Colors.ON_INVERSE_SURFACE),
        bgcolor=ft.Colors.INVERSE_SURFACE,
        trailing=theme_mode_button,
        title=ft.Text("CupertinoAppBar Example", color=ft.Colors.ON_INVERSE_SURFACE),
    )

    page.add(ft.Text("Body!"))


ft.run(main)

CupertinoAppBar

Bases: Control

An iOS-styled app bar.

Note

The alignment of the title depends on whether this app bar is large or not. If it is True, the title is left-aligned and if it is False (the default), the title is centered.

automatic_background_visibility

automatic_background_visibility: bool | None = None

Whether the navigation bar should appear transparent when content is scrolled under it.

If False, the navigation bar will display its bgcolor.

automatically_imply_leading

automatically_imply_leading: bool | None = None

Whether we should try to imply the leading control if None.

• If True and leading is None, the app bar will automatically determine an appropriate leading control.
• If False and leading is None, the space is allocated to the title.
• If a leading control is provided, this parameter has no effect.

automatically_imply_title

automatically_imply_title: bool | None = None

Whether we should try to imply the title control if None.

• If True and title is None, a Text control containing the current route's title will be automatically filled in.
• If the title is not None, this parameter has no effect.

badge

badge: BadgeValue | None = None

A badge to show on top of this control.

bgcolor

bgcolor: ColorValue | None = None

The fill color to use for this app bar.

Default color is defined by current theme.

border

border: Border | None = None

The border of the app bar. By default, a single pixel bottom border side is rendered.

brightness

brightness: Brightness | None = None

The brightness of the specified bgcolor.

Setting this value changes the style of the system status bar. It is typically used to increase the contrast ratio of the system status bar over bgcolor.

If None (the default), its value will be inferred from the relative luminance of the bgcolor.

col

col: ResponsiveNumber = 12

If a parent of this control is a ResponsiveRow, this property is used to determine how many virtual columns of a screen this control will span.

Can be a number or a dictionary configured to have a different value for specific breakpoints, for example col={"sm": 6}.

This control spans the 12 virtual columns by default.

Dimensions

Breakpoint	Dimension
xs	<576px
sm	≥576px
md	≥768px
lg	≥992px
xl	≥1200px
xxl	≥1400px

data

data: Any = skip_field()

Arbitrary data of any type.

disabled

disabled: bool = False

Every control has disabled property which is False by default - control and all its children are enabled.

Note

The value of this property will be propagated down to all children controls recursively.

Example

For example, if you have a form with multiple entry controls you can disable them all together by disabling container:

ft.Column(
    disabled = True,
    controls=[
        ft.TextField(),
        ft.TextField()
    ]
)

enable_background_filter_blur

enable_background_filter_blur: bool | None = None

Whether to have a blur effect when a non-opaque bgcolor is used.

This will only be respected when automatic_background_visibility is False or until content scrolls under the navigation bar.

expand

expand: bool | int | None = None

Specifies whether/how this control should expand to fill available space in its parent layout.

More information here.

Note

Has effect only if the direct parent of this control is one of the following controls, or their subclasses: Column, Row, View, Page.

expand_loose

expand_loose: bool = False

Allows the control to expand along the main axis if space is available, but does not require it to fill all available space.

More information here.

Note

If expand_loose is True, it will have effect only if:

• expand is not None and
• the direct parent of this control is one of the following controls, or their subclasses: Column, Row, View, Page.

key

key: (
    str | int | float | bool | ValueKey | ScrollKey | None
) = None

large

large: bool = False

Whether to use a large app bar layout.

If True, the title will be left-aligned and if it is False, the title will be centered.

leading

leading: Control | None = None

A control to display at the start of this app bar.

Typically the leading control is an Icon or an IconButton.

If it is None and automatically_imply_leading = True, an appropriate button will be automatically created.

opacity

opacity: Number = 1.0

Defines the transparency of the control.

Value ranges from 0.0 (completely transparent) to 1.0 (completely opaque without any transparency).

padding

padding: PaddingValue | None = None

Defines the padding for the contents of the app bar.

If None, the app bar will adopt the following defaults:

• vertically, contents will be sized to the same height as the app bar itself minus the status bar.
• horizontally, padding will be 16 pixels according to iOS specifications unless the leading widget is an automatically inserted back button, in which case the padding will be 0.

Note

Vertical padding (top and bottom) won't change the height of this app bar.

page

page: Page | PageView | None

The page (of type Page or PageView) to which this control belongs to.

parent

parent: BaseControl | None

The direct ancestor(parent) of this control.

It defaults to None and will only have a value when this control is mounted (added to the page tree).

The Page control (which is the root of the tree) is an exception - it always has parent=None.

previous_page_title

previous_page_title: str | None = None

Manually specify the previous route's title when automatically implying the leading back button.

Overrides the text shown with the back chevron instead of automatically showing the previous route's title when automatically_imply_leading is True.

Note

Has no effect if leading is not None or if automatically_imply_leading is False.

rtl

rtl: bool = False

Whether the text direction of the control should be right-to-left (RTL).

title

title: StrOrControl | None = None

A string or a control to display in the middle of this app bar.

Typically a Text.

tooltip

tooltip: TooltipValue | None = None

The tooltip ot show when this control is hovered over.

trailing

trailing: Control | None = None

A Control to place at the end of the app bar.

Typically used for actions such as searching or editing.

transition_between_routes

transition_between_routes: bool = True

Determines whether the app bar transitions between routes.

If True, this app bar will animate on top of route transitions when the destination route also contains a CupertinoAppBar or CupertinoSliverAppBar with transition_between_routes set to True.

This transition also occurs during edge back swipe gestures, mimicking native iOS behavior.

Note

When enabled, only one app bar can be present per route unless a hero_tag is specified.

visible

visible: bool = True

Every control has visible property which is True by default - control is rendered on the page. Setting visible to False completely prevents control (and all its children if any) from rendering on a page canvas. Hidden controls cannot be focused or selected with a keyboard or mouse and they do not emit any events.

before_event

before_event(e: ControlEvent)

before_update

before_update()

clean

clean() -> None

did_mount

did_mount()

init

init()

is_isolated

is_isolated()

update

update() -> None

will_unmount

will_unmount()