CupertinoAlertDialog

An iOS-style alert dialog that informs the user about situations that require acknowledgement.

import flet as ft

dialog = ft.CupertinoAlertDialog(
    title=ft.Text("Delete Item?"),
    content=ft.Text("This action cannot be undone."),
    actions=[
        ft.CupertinoDialogAction(
            content="Cancel",
            on_click=lambda e: print("Cancelled")
        ),
        ft.CupertinoDialogAction(
            content="Delete",
            destructive=True,
            on_click=lambda e: print("Deleted")
        )
    ]
)

Class signature

class CupertinoAlertDialog(DialogControl)

Properties

Whether this dialog cannot be dismissed by clicking the area outside of it.

title

str | Control

The title of this dialog, displayed in a large font at the top of this dialog.Typically a Text control.

content

Control

The content of this dialog, displayed in a light font at the center of this dialog.Typically a Column that contains the dialog’s Text message.

actions

list[Control]

A set of actions that are displayed at the bottom of the dialog.Typically this is a list of CupertinoDialogAction controls.

inset_animation

Animation

The animation style to be used when the system keyboard intrudes into the space that the dialog is placed in.

barrier_color

str

The color of the modal barrier below this dialog.If None, then DialogTheme.barrier_color is used. If that is also None, the default is Colors.BLACK_54.

Validation

The dialog requires at least one of the following to be visible:

title (as a string or visible Control)
content (as a visible Control)
At least one visible action in actions

If none of these conditions are met, a ValueError is raised.

iOS-specific behavior

Actions are arranged horizontally when there are two or fewer actions, vertically when there are more
The dialog has rounded corners matching iOS design guidelines
Backdrop blur effect is applied behind the dialog (platform-dependent)
Keyboard animation uses iOS-standard decelerate curve with 100ms duration

Comparison with Material

ft.CupertinoAlertDialog(
    title=ft.Text("Alert"),
    content=ft.Text("This is an iOS-style alert"),
    actions=[
        ft.CupertinoDialogAction(
            content="Cancel"
        ),
        ft.CupertinoDialogAction(
            content="OK",
            default=True
        )
    ]
)

Key differences:

CupertinoAlertDialog uses CupertinoDialogAction for actions, Material uses regular buttons
CupertinoAlertDialog has iOS-specific styling with rounded corners and blur effects
CupertinoAlertDialog automatically arranges actions based on count
CupertinoDialogAction supports default and destructive styling

Examples

Simple confirmation dialog

import flet as ft

def main(page: ft.Page):
    def close_dialog(e):
        dialog.open = False
        page.update()
    
    def show_dialog(e):
        dialog.open = True
        page.update()
    
    dialog = ft.CupertinoAlertDialog(
        title=ft.Text("Confirmation"),
        content=ft.Text("Are you sure you want to continue?"),
        actions=[
            ft.CupertinoDialogAction(
                content="No",
                on_click=close_dialog
            ),
            ft.CupertinoDialogAction(
                content="Yes",
                default=True,
                on_click=close_dialog
            )
        ]
    )
    
    page.overlay.append(dialog)
    page.add(
        ft.CupertinoButton(
            content="Show Dialog",
            on_click=show_dialog
        )
    )

ft.app(target=main)

Destructive action dialog

import flet as ft

def main(page: ft.Page):
    def delete_item(e):
        dialog.open = False
        print("Item deleted")
        page.update()
    
    def cancel(e):
        dialog.open = False
        page.update()
    
    def show_delete_dialog(e):
        dialog.open = True
        page.update()
    
    dialog = ft.CupertinoAlertDialog(
        title=ft.Text("Delete Item"),
        content=ft.Text(
            "This action cannot be undone. The item will be permanently deleted."
        ),
        actions=[
            ft.CupertinoDialogAction(
                content="Cancel",
                on_click=cancel
            ),
            ft.CupertinoDialogAction(
                content="Delete",
                destructive=True,
                on_click=delete_item
            )
        ]
    )
    
    page.overlay.append(dialog)
    page.add(
        ft.CupertinoButton(
            content="Delete Item",
            on_click=show_delete_dialog
        )
    )

ft.app(target=main)

Multi-option dialog

import flet as ft

def main(page: ft.Page):
    def handle_action(action_name):
        def handler(e):
            dialog.open = False
            print(f"Selected: {action_name}")
            page.update()
        return handler
    
    def show_options(e):
        dialog.open = True
        page.update()
    
    dialog = ft.CupertinoAlertDialog(
        title=ft.Text("Choose an option"),
        content=ft.Text("Select one of the following actions:"),
        actions=[
            ft.CupertinoDialogAction(
                content="Option 1",
                on_click=handle_action("Option 1")
            ),
            ft.CupertinoDialogAction(
                content="Option 2",
                on_click=handle_action("Option 2")
            ),
            ft.CupertinoDialogAction(
                content="Option 3",
                on_click=handle_action("Option 3")
            ),
            ft.CupertinoDialogAction(
                content="Cancel",
                default=True,
                on_click=handle_action("Cancel")
            )
        ]
    )
    
    page.overlay.append(dialog)
    page.add(
        ft.CupertinoButton(
            content="Show Options",
            on_click=show_options
        )
    )

ft.app(target=main)

CupertinoDialogAction

A button used in Cupertino-style dialogs.

import flet as ft

ft.CupertinoDialogAction(
    content="OK",
    default=True,
    on_click=lambda e: print("OK clicked")
)

Class signature

class CupertinoDialogAction(Control)

Properties

content

str | Control

required

The content of this action button.Must be either a string or a visible Control.

default

bool

default:"False"

Whether this action is a default action. In this case, the button will have bold text.Multiple actions can have this property set to True in a CupertinoAlertDialog.

destructive

bool

default:"False"

If set to True, this button’s text color will be red.Typically used for actions that destroy objects, such as a delete action that deletes an email.

text_style

TextStyle

The text style to use for text in this button.Can be useful when content is a string.

Events

on_click

ControlEventHandler

Called when a user clicks this button.

Validation

The content must be either a string or a visible Control. A ValueError is raised if this condition is not met.

Usage notes

Typically used as a child of CupertinoAlertDialog.actions or CupertinoActionSheet.actions
The default property adds bold text styling to emphasize the recommended action
The destructive property adds red text color to warn about dangerous actions
Both default and destructive can be used on different actions in the same dialog

Core

Material Controls

Cupertino Controls

Layout Controls

Services

Utilities

CupertinoAlertDialog