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Dropdown

A material design button for selecting from a list of items.

A dropdown lets the user select from a number of items. The dropdown shows the currently selected item as well as an arrow that opens a menu for selecting another item.

Examples​

Live example

Basic dropdown​

import flet as ft

def main(page: ft.Page):
    def button_clicked(e):
        t.value = f"Dropdown value is:  {dd.value}"
        page.update()

    t = ft.Text()
    b = ft.ElevatedButton(text="Submit", on_click=button_clicked)
    dd = ft.Dropdown(
        width=100,
        options=[
            ft.dropdown.Option("Red"),
            ft.dropdown.Option("Green"),
            ft.dropdown.Option("Blue"),
        ],
    )
    page.add(dd, b, t)

ft.app(target=main)
import flet as ft

def main(page: ft.Page):
    page.add(
        ft.Dropdown(
            label="Color",
            hint_text="Choose your favourite color?",
            options=[
                ft.dropdown.Option("Red"),
                ft.dropdown.Option("Green"),
                ft.dropdown.Option("Blue"),
            ],
            autofocus=True,
        )
    )

ft.app(target=main)
import flet as ft

def main(page: ft.Page):
    def dropdown_changed(e):
        t.value = f"Dropdown changed to {dd.value}"
        page.update()

    t = ft.Text()
    dd = ft.Dropdown(
        on_change=dropdown_changed,
        options=[
            ft.dropdown.Option("Red"),
            ft.dropdown.Option("Green"),
            ft.dropdown.Option("Blue"),
        ],
        width=200,
    )
    page.add(dd, t)

ft.app(target=main)

Change items in dropdown options​

import flet as ft

def main(page: ft.Page):
    def find_option(option_name):
        for option in d.options:
            if option_name == option.key:
                return option
        return None

    def add_clicked(e):
        d.options.append(ft.dropdown.Option(option_textbox.value))
        d.value = option_textbox.value
        option_textbox.value = ""
        page.update()

    def delete_clicked(e):
        option = find_option(d.value)
        if option != None:
            d.options.remove(option)
            # d.value = None
            page.update()

    d = ft.Dropdown()
    option_textbox = ft.TextField(hint_text="Enter item name")
    add = ft.ElevatedButton("Add", on_click=add_clicked)
    delete = ft.OutlinedButton("Delete selected", on_click=delete_clicked)
    page.add(d, ft.Row(controls=[option_textbox, add, delete]))

ft.app(target=main)

alignment​

Defines how the hint or the selected item is positioned within the dropdown.

See Container.alignment property for possible values.

autofocus​

True if the control will be selected as the initial focus. If there is more than one control on a page with autofocus set, then the first one added to the page will get focus.

bgcolor​

Dropdown background color.

border​

Border around input - InputBorder enum with one of the values: OUTLINE (default), UNDERLINE, NONE.

border_color​

Border color. Could be transparent to hide the border.

border_radius​

See [Container.border_radius] property docs for more information about border radius.

border_width​

The width of the border in virtual pixels. Default is 1. Set to 0 to completely remove border.

color​

Text color.

content_padding​

The padding for the input decoration's container.

counter_style​

The style to use for counter_text.

counter_text​

Optional text to place below the line as a character count.

If null or an empty string and counter isn't specified, then nothing will appear in the counter's location.

dense​

Whether the TextField is part of a dense form (ie, uses less vertical space).

error_style​

The style to use for error_text.

error_text​

Text that appears below the input border.

If non-null, the border's color animates to red and the helper_text is not shown.

filled​

If True the decoration's container is filled with theme fillColor.

focused_bgcolor​

Background color of dropdown in focused state.

focused_border_color​

Border color in focused state.

focused_border_width​

Border width in focused state.

focused_color​

Text color when Dropdown is focused.

helper_style​

The style to use for helper_text.

helper_text​

Text that provides context about the input's value, such as how the value will be used.

If non-null, the text is displayed below the input decorator, in the same location as error_text. If a non-null error_text value is specified then the helper text is not shown.

hint_style​

The style to use for hint_text.

hint_text​

Text that suggests what sort of input the field accepts.

Displayed on top of the input when it's empty and either (a) label is null or (b) the input has the focus.

icon​

The name of the icon to show before the input field and outside of the decoration's container.

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

label​

Optional text that describes the input field.

When the input field is empty and unfocused, the label is displayed on top of the input field (i.e., at the same location on the screen where text may be entered in the input field). When the input field receives focus (or if the field is non-empty) the label moves above, either vertically adjacent to, or to the center of the input field.

label_style​

The style to use for label.

options​

A list of Option controls representing items in the dropdown.

prefix​

Optional Control to place on the line before the input.

This can be used, for example, to add some padding to text that would otherwise be specified using prefix_text, or to add a custom control in front of the input. The control's baseline is lined up with the input baseline.

Only one of prefix and prefix_text can be specified.

The prefix appears after the prefix_icon, if both are specified.

prefix_icon​

An icon that appears before the prefix or prefix_text and before the editable part of the text field, within the decoration's container.

prefix_style​

The style to use for prefix_text.

prefix_text​

Optional text prefix to place on the line before the input.

suffix​

Optional Control to place on the line after the input.

This can be used, for example, to add some padding to the text that would otherwise be specified using suffix_text, or to add a custom control after the input. The control's baseline is lined up with the input baseline.

Only one of suffix and suffix_text can be specified.

The suffix appears before the suffix_icon, if both are specified.

suffix_icon​

An icon that appears after the editable part of the text field and after the suffix or suffix_text, within the decoration's container.

suffix_style​

The style to use for suffix_text.

suffix_text​

Optional text suffix to place on the line after the input.

text_size​

Text size in virtual pixels.

text_style​

The text style to use for text in the dropdown button and the dropdown menu that appears when you tap the button.

value​

key value of the selected option.

focus()​

Moves focus to a Dropdown.

on_blur​

Fires when the control has lost focus.

on_change​

Fires when the selected item of the Dropdown has changed.

on_focus​

Fires when the control has received focus.

Option properties​

key​

Option's key. text value will be used instead if key is not specified.

text​

Option's display text. key value will be used instead if text is not specified.