BasePage

Inherits: AdaptiveControl

A visual container representing a top-level view in a Flet application.

BasePage serves as the base class for Page and MultiView, and provides a unified surface for rendering application content, app bars, navigation elements, dialogs, overlays, and more. It manages one or more View instances and exposes high-level layout, scrolling, and theming properties.

Unlike lower-level layout controls (e.g., Column, Container), BasePage represents an entire logical view or screen of the app. It provides direct access to view-level controls such as AppBar, NavigationBar, FloatingActionButton, and supports system-level events like window resizing and media changes.

This class is not intended to be used directly in most apps; instead, use Page or MultiView, which extend this base functionality.

Properties

• appbar(AppBar | CupertinoAppBar | None) –

  Gets or sets the top application bar (AppBar or CupertinoAppBar) for the view.

• auto_scroll(bool) –

  Whether root view should auto-scroll to the end on content changes.

• bgcolor(ColorValue | None) –

  Background color of the root view.

• bottom_appbar(BottomAppBar | None) –

  Bottom app bar displayed in the root view.

• controls(list[BaseControl]) –

  Root view content controls displayed by this page.

• dark_theme(Theme | None) –

  Customizes the theme of the application when in dark theme mode.

• decoration(BoxDecoration | None) –

  Background decoration of the root view container.

• drawer(NavigationDrawer | None) –

  Navigation drawer opened from the leading edge.

• enable_screenshots(bool) –

  Enable taking screenshots of the entire page with take_screenshot method.

• end_drawer(NavigationDrawer | None) –

  Navigation drawer opened from the trailing edge.

• floating_action_button(FloatingActionButton | None) –

  Floating action button shown for the root view.

• floating_action_button_location(FloatingActionButtonLocation | OffsetValue | None) –

  Placement of the floating action button in the root view.

• foreground_decoration(BoxDecoration | None) –

  Foreground decoration painted above root view content.

• height(Number | None) –

  Page height in logical pixels.

• horizontal_alignment(CrossAxisAlignment) –

  Horizontal alignment of root view child controls.

• locale_configuration(LocaleConfiguration | None) –

  Configures supported locales and the current locale.

• media(PageMediaData) –

  The current environmental metrics of the page or window.

• navigation_bar(NavigationBar | CupertinoNavigationBar | None) –

  Bottom navigation bar for the root view.

• overlay(list[BaseControl]) –

  The list of overlay controls rendered above page content.

• padding(PaddingValue | None) –

  Inner padding for the root view content.

• scroll(ScrollMode | None) –

  Scroll behavior mode for root view content.

• services(list[Service]) –

  Service instances attached to the root view lifecycle.

• show_semantics_debugger(bool | None) –

  Whether to turn on an overlay that shows the accessibility information reported by the framework.

• spacing(Number) –

  Default spacing between root view child controls.

• theme(Theme | None) –

  Customizes the theme of the application when in light theme mode. Currently, a theme can only be automatically generated from a "seed" color. For example, to generate light theme from a green color.

• theme_mode(ThemeMode | None) –

  The page's theme mode.

• title(str | None) –

  Page or window title.

• vertical_alignment(MainAxisAlignment) –

  Vertical alignment of root view child controls.

• views(list[View]) –

  A list of views managed by the page.

• width(Number | None) –

  Page width in logical pixels.

Events

• on_media_change(EventHandler[PageMediaData] | None) –

  Called when media has changed.

• on_resize(EventHandler[PageResizeEvent] | None) –

  Called when a user resizes a browser or native OS window containing Flet app

Methods

• add –

  Adds controls to the page.

• clean –

  Remove all root view controls and send update to the client.

• close_drawer –

  Close the drawer.

• close_end_drawer –

  Close the end drawer.

• insert –

  Inserts controls at specific index of page.controls list.

• pop_dialog –

  Closes the most recently opened dialog.

• remove –

  Removes specific controls from page.controls list.

• remove_at –

  Remove controls from page.controls list at specific index.

• scroll_to –

  Moves scroll position to either absolute offset, relative delta or jump to the control with specified scroll_key.

• show_dialog –

  Displays a dialog and manages its dismissal lifecycle.

• show_drawer –

  Show the drawer.

• show_end_drawer –

  Show the end drawer.

• take_screenshot –

  Captures a screenshot of the entire page with overlays.

• update –

  Push pending updates to the connected client.

Properties

appbar property writable

appbar: AppBar | CupertinoAppBar | None

Gets or sets the top application bar (AppBar or CupertinoAppBar) for the view.

The app bar typically displays the page title and optional actions such as navigation icons, menus, or other interactive elements.

auto_scroll property writable

auto_scroll: bool

Whether root view should auto-scroll to the end on content changes.

bgcolor property writable

bgcolor: ColorValue | None

Background color of the root view.

bottom_appbar property writable

bottom_appbar: BottomAppBar | None

Bottom app bar displayed in the root view.

controls property writable

controls: list[BaseControl]

Root view content controls displayed by this page.

dark_theme class-attribute instance-attribute

dark_theme: Theme | None = None

Customizes the theme of the application when in dark theme mode.

decoration property writable

decoration: BoxDecoration | None

Background decoration of the root view container.

drawer property writable

drawer: NavigationDrawer | None

Navigation drawer opened from the leading edge.

enable_screenshots class-attribute instance-attribute

enable_screenshots: bool = False

Enable taking screenshots of the entire page with take_screenshot method.

end_drawer property writable

end_drawer: NavigationDrawer | None

Navigation drawer opened from the trailing edge.

floating_action_button property writable

floating_action_button: FloatingActionButton | None

Floating action button shown for the root view.

floating_action_button_location property writable

floating_action_button_location: (
    FloatingActionButtonLocation | OffsetValue | None
)

Placement of the floating action button in the root view.

foreground_decoration property writable

foreground_decoration: BoxDecoration | None

Foreground decoration painted above root view content.

height class-attribute instance-attribute

height: Number | None = None

Page height in logical pixels.

Note

• This property is read-only.
• To get or set the full window height including window chrome (e.g., title bar and borders) when running a Flet app on desktop, use the height property of Page.window instead.

horizontal_alignment property writable

horizontal_alignment: CrossAxisAlignment

Horizontal alignment of root view child controls.

locale_configuration class-attribute instance-attribute

locale_configuration: LocaleConfiguration | None = None

Configures supported locales and the current locale.

media class-attribute instance-attribute

media: PageMediaData = field(
    default_factory=lambda: PageMediaData(
        padding=zero(),
        view_padding=zero(),
        view_insets=zero(),
        device_pixel_ratio=0,
        orientation=PORTRAIT,
        always_use_24_hour_format=False,
    )
)

The current environmental metrics of the page or window.

This data is updated whenever the platform window or layout changes, such as when rotating a device, resizing a browser window, or adjusting system UI elements like the keyboard or safe areas.

navigation_bar property writable

navigation_bar: (
    NavigationBar | CupertinoNavigationBar | None
)

Bottom navigation bar for the root view.

overlay property

overlay: list[BaseControl]

The list of overlay controls rendered above page content.

padding property writable

padding: PaddingValue | None

Inner padding for the root view content.

scroll property writable

scroll: ScrollMode | None

Scroll behavior mode for root view content.

services property writable

services: list[Service]

Service instances attached to the root view lifecycle.

show_semantics_debugger class-attribute instance-attribute

show_semantics_debugger: bool | None = None

Whether to turn on an overlay that shows the accessibility information reported by the framework.

spacing property writable

spacing: Number

Default spacing between root view child controls.

theme class-attribute instance-attribute

theme: Theme | None = None

Customizes the theme of the application when in light theme mode. Currently, a theme can only be automatically generated from a "seed" color. For example, to generate light theme from a green color.

theme_mode class-attribute instance-attribute

theme_mode: ThemeMode | None = SYSTEM

The page's theme mode.

title class-attribute instance-attribute

title: str | None = None

Page or window title.

vertical_alignment property writable

vertical_alignment: MainAxisAlignment

Vertical alignment of root view child controls.

views class-attribute instance-attribute

views: list[View] = field(default_factory=lambda: [View()])

A list of views managed by the page.

Each View represents a distinct navigation state or screen in the application.

The first view in the list is considered the active one by default.

width class-attribute instance-attribute

width: Number | None = None

Page width in logical pixels.

Note

• This property is read-only.
• To get or set the full window height including window chrome (e.g., title bar and borders) when running a Flet app on desktop, use the width property of Page.window instead.

Events

on_media_change class-attribute instance-attribute

on_media_change: EventHandler[PageMediaData] | None = None

Called when media has changed.

on_resize class-attribute instance-attribute

on_resize: EventHandler[PageResizeEvent] | None = None

Called when a user resizes a browser or native OS window containing Flet app

Example

def main(page: ft.Page):
    def handle_page_size(e):
        print("New page size:", page.window.width, page.window_height)

    page.on_resize = handle_page_size

Methods

add

add(*controls: Control) -> None

Adds controls to the page.

Example:

page.add(ft.Text("Hello!"), ft.FilledButton("Button"))

clean

clean() -> None

Remove all root view controls and send update to the client.

close_drawer async

close_drawer()

Close the drawer.

close_end_drawer async

close_end_drawer()

Close the end drawer.

insert

insert(at: int, *controls: Control) -> None

Inserts controls at specific index of page.controls list.

pop_dialog

pop_dialog() -> DialogControl | None

Closes the most recently opened dialog.

This method searches the active dialog stack for the topmost dialog that is currently open, marks it as closed, updates its state, and returns the closed dialog.

Returns:

• DialogControl | None –

  The closed dialog instance if one was found, otherwise None.

remove

remove(*controls: Control) -> None

Removes specific controls from page.controls list.

remove_at

remove_at(index: int) -> None

Remove controls from page.controls list at specific index.

scroll_to async

scroll_to(
    offset: Number | None = None,
    delta: Number | None = None,
    scroll_key: ScrollKey
    | str
    | int
    | float
    | bool
    | None = None,
    duration: DurationValue | None = None,
    curve: AnimationCurve | None = None,
) -> None

Moves scroll position to either absolute offset, relative delta or jump to the control with specified scroll_key.

See Column.scroll_to() for method details and examples.

show_dialog

show_dialog(dialog: DialogControl) -> None

Displays a dialog and manages its dismissal lifecycle.

This method adds the specified dialog to the active dialog stack and renders it on the page. The on_dismiss handler of the dialog is temporarily wrapped to ensure the dialog is removed from the stack and its dismissal event is triggered appropriately.

Parameters:

• dialog (DialogControl) –

  The dialog instance to display. Must not yet be open.

Raises:

• RuntimeError –

  If the specified dialog is already open.

show_drawer async

show_drawer()

Show the drawer.

Raises:

• ValueError –

  If no drawer is defined.

show_end_drawer async

show_end_drawer()

Show the end drawer.

Raises:

• ValueError –

  If no end_drawer is defined.

take_screenshot async

take_screenshot(
    pixel_ratio: Number | None = None,
    delay: DurationValue | None = None,
) -> bytes

Captures a screenshot of the entire page with overlays.

Parameters:

• pixel_ratio (Number | None, default: None ) –

  A pixel ratio of the captured screenshot. If None, device-specific pixel ratio will be used.

• delay (DurationValue | None, default: None ) –

  A delay before taking a screenshot. The delay will be 20 milliseconds if not specified.

Returns:

• bytes –

  Screenshot in PNG format.

update

update(*controls: Control) -> None

Push pending updates to the connected client.

Parameters:

• *controls (Control, default: () ) –

  Specific controls to update. When omitted, updates this page object.