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PieChart

PieChart #

Bases: ConstrainedControl

A pie chart control displaying multiple sections as slices of a circle.

Overview

animate_offset #

animate_offset: AnimationValue | None = None

Setting control's animate_offset to either True, number or an instance of animation.Animation class enables implicit animation of Control.offset property.

offset property is an instance of transform.Offset class which specifies horizontal x and vertical y offset of a control scaled to control's size. For example, an offset transform.Offset(-0.25, 0) will result in a horizontal translation of one quarter the width of the control.

Offset animation is used for various sliding effects:

import flet as ft

def main(page: ft.Page):

    c = ft.Container(
        width=150,
        height=150,
        bgcolor="blue",
        border_radius=10,
        offset=ft.transform.Offset(-2, 0),
        animate_offset=ft.animation.Animation(1000),
    )

    def animate(e):
        c.offset = ft.transform.Offset(0, 0)
        c.update()

    page.add(
        c,
        ft.ElevatedButton("Reveal!", on_click=animate),
    )

ft.run(main)

animate_opacity #

animate_opacity: AnimationValue | None = None

Setting control's animate_opacity to either True, number or an instance of animation.Animation class enables implicit animation of Control.opacity property.

import flet as ft

def main(page: ft.Page):

    c = ft.Container(
        width=150,
        height=150,
        bgcolor="blue",
        border_radius=10,
        animate_opacity=300,
    )

    def animate_opacity(e):
        c.opacity = 0 if c.opacity == 1 else 1
        c.update()

    page.add(
        c,
        ft.ElevatedButton(
            "Animate opacity",
            on_click=animate_opacity,
        ),
    )

ft.app(main)

animate_position #

animate_position: AnimationValue | None = None

Setting control's animate_position to either True, number or an instance of animation.Animation class (see above) enables implicit animation of Control's left, top, right and bottom properties.

Please note Control position works inside Stack control only.

import flet as ft

def main(page: ft.Page):

    c1 = ft.Container(width=50, height=50, bgcolor="red", animate_position=1000)

    c2 = ft.Container(
        width=50, height=50, bgcolor="green", top=60, left=0, animate_position=500
    )

    c3 = ft.Container(
        width=50, height=50, bgcolor="blue", top=120, left=0, animate_position=1000
    )

    def animate_container(e):
        c1.top = 20
        c1.left = 200
        c2.top = 100
        c2.left = 40
        c3.top = 180
        c3.left = 100
        page.update()

    page.add(
        ft.Stack([c1, c2, c3], height=250),
        ft.ElevatedButton("Animate!", on_click=animate_container),
    )

ft.run(main)

animate_rotation #

animate_rotation: AnimationValue | None = None

Setting control's animate_rotation to either True, number or an instance of animation.Animation class enables implicit animation of Control.rotate property.

from math import pi
import flet as ft

def main(page: ft.Page):

    c = ft.Container(
        width=100,
        height=70,
        bgcolor="blue",
        border_radius=5,
        rotate=ft.transform.Rotate(0, alignment=ft.Alignment.CENTER),
        animate_rotation=ft.animation.Animation(300, ft.AnimationCurve.BOUNCE_OUT),
    )

    def animate(e):
        c.rotate.angle += pi / 2
        page.update()

    page.vertical_alignment = ft.MainAxisAlignment.CENTER
    page.horizontal_alignment = ft.CrossAxisAlignment.CENTER
    page.spacing = 30
    page.add(
        c,
        ft.ElevatedButton("Animate!", on_click=animate),
    )

ft.run(main)

animate_scale #

animate_scale: AnimationValue | None = None

Setting control's animate_scale to either True, number or an instance of animation.Animation class enables implicit animation of Control.scale property.

import flet as ft

def main(page: ft.Page):

    c = ft.Container(
        width=100,
        height=100,
        bgcolor="blue",
        border_radius=5,
        scale=ft.transform.Scale(scale=1),
        animate_scale=ft.animation.Animation(600, ft.AnimationCurve.BOUNCE_OUT),
    )

    def animate(e):
        c.scale = 2
        page.update()

    page.vertical_alignment = ft.MainAxisAlignment.CENTER
    page.horizontal_alignment = ft.CrossAxisAlignment.CENTER
    page.spacing = 30
    page.add(
        c,
        ft.ElevatedButton("Animate!", on_click=animate),
    )

ft.run(main)

animate_size #

animate_size: AnimationValue | None = None

TBD

animation #

animation: AnimationValue = field(
    default_factory=lambda: Animation(
        duration=Duration(milliseconds=150), curve=LINEAR
    )
)

Controls chart implicit animation.

aspect_ratio #

aspect_ratio: OptionalNumber = None

TBD

badge #

badge: BadgeValue | None = None

The badge property supports both strings and Badge objects.

bottom #

bottom: OptionalNumber = None

Effective inside Stack only. The distance that the child's bottom edge is inset from the bottom of the stack.

center_space_color #

center_space_color: ColorValue | None = None

Free space color in the middle of a chart.

center_space_radius #

center_space_radius: Number | None = None

Free space radius in the middle of a chart.

col #

col: ResponsiveNumber = 12

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

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

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

If col property is not specified, it spans the maximum number of columns (12).

data #

data: Any = skip_field()

Arbitrary data of any type that can be attached to a control.

disabled #

disabled: bool = False

Every control has disabled property which is False by default - control and all its children are enabled. disabled property is mostly used with data entry controls like TextField, Dropdown, Checkbox, buttons. However, disabled could be set to a parent control and its value will be propagated down to all children recursively.

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

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

expand #

expand: bool | int | None = None

When a child Control is placed into a Column or a Row you can "expand" it to fill the available space. expand property could be a boolean value (True - expand control to fill all available space) or an integer - an "expand factor" specifying how to divide a free space with other expanded child controls.

For more information and examples about expand property see "Expanding children" sections in Column or Row.

Here is an example of expand being used in action for both Column and Row:

import flet as ft

def main(page: ft.Page):
    page.spacing = 0
    page.padding = 0
    page.add(
        ft.Column(
            controls=[
                ft.Row(
                    [
                        ft.Card(
                            content=ft.Text("Card_1"),
                            color=ft.Colors.ORANGE_300,
                            expand=True,
                            height=page.height,
                            margin=0,
                        ),
                        ft.Card(
                            content=ft.Text("Card_2"),
                            color=ft.Colors.GREEN_100,
                            expand=True,
                            height=page.height,
                            margin=0,
                        ),
                    ],
                    expand=True,
                    spacing=0,
                ),
            ],
            expand=True,
            spacing=0,
        ),
    )

ft.app(main)

expand_loose #

expand_loose: bool | None = None

Effective only if expand is True.

If expand_loose is True, the child control of a Column or a Row will be given the flexibility to expand to fill the available space in the main axis (e.g., horizontally for a Row or vertically for a Column), but will not be required to fill the available space.

The default value is False.

Here is the example of Containers placed in Rows with expand_loose = True: 

import flet as ft


class Message(ft.Container):
    def __init__(self, author, body):
        super().__init__()
        self.content = ft.Column(
            controls=[
                ft.Text(author, weight=ft.FontWeight.BOLD),
                ft.Text(body),
            ],
        )
        self.border = ft.border.all(1, ft.Colors.BLACK)
        self.border_radius = ft.border_radius.all(10)
        self.bgcolor = ft.Colors.GREEN_200
        self.padding = 10
        self.expand = True
        self.expand_loose = True


def main(page: ft.Page):
    chat = ft.ListView(
        padding=10,
        spacing=10,
        controls=[
            ft.Row(
                alignment=ft.MainAxisAlignment.START,
                controls=[
                    Message(
                        author="John",
                        body="Hi, how are you?",
                    ),
                ],
            ),
            ft.Row(
                alignment=ft.MainAxisAlignment.END,
                controls=[
                    Message(
                        author="Jake",
                        body="Hi I am good thanks, how about you?",
                    ),
                ],
            ),
            ft.Row(
                alignment=ft.MainAxisAlignment.START,
                controls=[
                    Message(
                        author="John",
                        body="Lorem Ipsum is simply dummy text of the printing and 
                        typesetting industry. Lorem Ipsum has been the industry's 
                        standard dummy text ever since the 1500s, when an unknown 
                        printer took a galley of type and scrambled it to make a 
                        type specimen book.",
                    ),
                ],
            ),
            ft.Row(
                alignment=ft.MainAxisAlignment.END,
                controls=[
                    Message(
                        author="Jake",
                        body="Thank you!",
                    ),
                ],
            ),
        ],
    )

    page.window.width = 393
    page.window.height = 600
    page.window.always_on_top = False

    page.add(chat)


ft.run(main)

height #

height: OptionalNumber = None

Imposed Control height in virtual pixels.

key #

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

left #

left: OptionalNumber = None

Effective inside Stack only. The distance that the child's left edge is inset from the left of the stack.

offset #

offset: OffsetValue | None = None

Applies a translation transformation before painting the control.

The translation is expressed as a transform.Offset scaled to the control's size. For example, an Offset with a x of 0.25 will result in a horizontal translation of one quarter the width of the control.

The following example displays container at 0, 0 top left corner of a stack as transform applies -1 * 100, -1 * 100 (offset * control_size) horizontal and vertical translations to the control:

import flet as ft

def main(page: ft.Page):

    page.add(
        ft.Stack(
            [
                ft.Container(
                    bgcolor="red",
                    width=100,
                    height=100,
                    left=100,
                    top=100,
                    offset=ft.transform.Offset(-1, -1),
                )
            ],
            width=1000,
            height=1000,
        )
    )

ft.run(main)

on_animation_end #

on_animation_end: OptionalControlEventHandler[
    ConstrainedControl
] = None

All controls with animate_* properties have on_animation_end event handler which is called when animation complete and can be used to chain multiple animations.

Event's object data field contains the name of animation:

  • opacity
  • rotation
  • scale
  • offset
  • position
  • container

For example:

c = ft.Container(
        ft.Text("Animate me!"),
        # ...
        animate=ft.animation.Animation(1000, "bounceOut"),
        on_animation_end=lambda e: print("Container animation end:", e.data)
    )

on_event #

on_event: EventHandler[PieChartEvent] | None = None

Fires when a chart section is hovered or clicked.

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) and defaults to 1.0.

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.

right #

right: OptionalNumber = None

Effective inside Stack only. The distance that the child's right edge is inset from the right of the stack.

rotate #

rotate: RotateValue | None = None

Transforms control using a rotation around the center.

The value of rotate property could be one of the following types:

  • number - a rotation in clockwise radians. Full circle 360° is math.pi * 2 radians, 90° is pi / 2, 45° is pi / 4, etc.
  • transform.Rotate - allows to specify rotation angle as well as alignment - the location of rotation center.

For example:

ft.Image(
    src="https://picsum.photos/100/100",
    width=100,
    height=100,
    border_radius=5,
    rotate=Rotate(angle=0.25 * pi, alignment=ft.Alignment.CENTER_LEFT)
)

rtl #

rtl: bool = False

True to set text direction to right-to-left.

scale #

scale: ScaleValue | None = None

Scale control along the 2D plane. Default scale factor is 1.0 - control is not scaled. 0.5 - the control is twice smaller, 2.0 - the control is twice larger.

Different scale multipliers can be specified for x and y axis, but setting Control.scale property to an instance of transform.Scale class.

Either scale or scale_x and scale_y could be specified, but not all of them, for example:

ft.Image(
    src="https://picsum.photos/100/100",
    width=100,
    height=100,
    border_radius=5,
    scale=Scale(scale_x=2, scale_y=0.5)
)

sections #

sections: list[PieChartSection] = field(
    default_factory=list
)

A list of PieChartSection controls drawn in a circle.

sections_space #

sections_space: Number | None = None

A gap between sections.

start_degree_offset #

start_degree_offset: Number | None = None

By default, sections are drawn from zero degree (right side of the circle) clockwise. You can change the starting point by setting start_degree_offset (in degrees).

tooltip #

tooltip: TooltipValue | None = None

The tooltip property supports both strings and Tooltip objects.

top #

top: OptionalNumber = None

Effective inside Stack only. The distance that the child's top edge is inset from the top of the stack.

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.

width #

width: OptionalNumber = None

Imposed Control width in virtual pixels.

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()

Examples#

Example 1#

PieChart example 1

import flet as ft

import flet_charts as fch


def main(page: ft.Page):
    normal_border = ft.BorderSide(0, ft.Colors.with_opacity(0, ft.Colors.WHITE))
    hovered_border = ft.BorderSide(6, ft.Colors.SECONDARY)

    def on_chart_event(e: fch.PieChartEvent):
        for idx, section in enumerate(chart.sections):
            section.border_side = (
                hovered_border if idx == e.section_index else normal_border
            )
        chart.update()

    chart = fch.PieChart(
        sections_space=1,
        center_space_radius=0,
        on_event=on_chart_event,
        expand=True,
        sections=[
            fch.PieChartSection(
                value=25,
                color=ft.Colors.BLUE,
                radius=80,
                border_side=normal_border,
            ),
            fch.PieChartSection(
                value=25,
                color=ft.Colors.YELLOW,
                radius=65,
                border_side=normal_border,
            ),
            fch.PieChartSection(
                value=25,
                color=ft.Colors.PINK,
                radius=60,
                border_side=normal_border,
            ),
            fch.PieChartSection(
                value=25,
                color=ft.Colors.GREEN,
                radius=70,
                border_side=normal_border,
            ),
        ],
    )

    page.add(chart)


ft.run(main)

Example 2#

PieChart example 2

import flet as ft

import flet_charts as fch


NORMAL_RADIUS = 50
HOVER_RADIUS = 60
NORMAL_TITLE_STYLE = ft.TextStyle(
    size=16, color=ft.Colors.WHITE, weight=ft.FontWeight.BOLD
)
HOVER_TITLE_STYLE = ft.TextStyle(
    size=22,
    color=ft.Colors.WHITE,
    weight=ft.FontWeight.BOLD,
    shadow=ft.BoxShadow(blur_radius=2, color=ft.Colors.BLACK54),
)


def main(page: ft.Page):
    def on_chart_event(e: fch.PieChartEvent):
        for idx, section in enumerate(chart.sections):
            if idx == e.section_index:
                section.radius = HOVER_RADIUS
                section.title_style = HOVER_TITLE_STYLE
            else:
                section.radius = NORMAL_RADIUS
                section.title_style = NORMAL_TITLE_STYLE
        chart.update()

    chart = fch.PieChart(
        expand=True,
        sections_space=0,
        center_space_radius=40,
        on_event=on_chart_event,
        sections=[
            fch.PieChartSection(
                value=40,
                title="40%",
                title_style=NORMAL_TITLE_STYLE,
                color=ft.Colors.BLUE,
                radius=NORMAL_RADIUS,
            ),
            fch.PieChartSection(
                value=30,
                title="30%",
                title_style=NORMAL_TITLE_STYLE,
                color=ft.Colors.YELLOW,
                radius=NORMAL_RADIUS,
            ),
            fch.PieChartSection(
                value=15,
                title="15%",
                title_style=NORMAL_TITLE_STYLE,
                color=ft.Colors.PURPLE,
                radius=NORMAL_RADIUS,
            ),
            fch.PieChartSection(
                value=15,
                title="15%",
                title_style=NORMAL_TITLE_STYLE,
                color=ft.Colors.GREEN,
                radius=NORMAL_RADIUS,
            ),
        ],
    )

    page.add(chart)


ft.run(main)

Example 3#

PieChart example 3

import flet_charts as fch

import flet as ft

NORMAL_RADIUS = 100
HOVER_RADIUS = 110
NORMAL_TITLE_STYLE = ft.TextStyle(
    size=12, color=ft.Colors.WHITE, weight=ft.FontWeight.BOLD
)
HOVER_TITLE_STYLE = ft.TextStyle(
    size=16,
    color=ft.Colors.WHITE,
    weight=ft.FontWeight.BOLD,
    shadow=ft.BoxShadow(blur_radius=2, color=ft.Colors.BLACK54),
)
NORMAL_BADGE_SIZE = 40
HOVER_BADGE_SIZE = 50


class SectionBadge(ft.Container):
    def __init__(self, icon: ft.IconValue, size: int = NORMAL_BADGE_SIZE):
        super().__init__(
            content=ft.Icon(icon),
            width=size,
            height=size,
            border=ft.Border.all(1, ft.Colors.BROWN),
            border_radius=size / 2,
            bgcolor=ft.Colors.WHITE,
        )


def main(page: ft.Page):
    def on_chart_event(e: fch.PieChartEvent):
        for idx, section in enumerate(chart.sections):
            if idx == e.section_index:
                section.radius = HOVER_RADIUS
                section.title_style = HOVER_TITLE_STYLE
            else:
                section.radius = NORMAL_RADIUS
                section.title_style = NORMAL_TITLE_STYLE
        chart.update()

    chart = fch.PieChart(
        sections_space=0,
        center_space_radius=0,
        on_event=on_chart_event,
        expand=True,
        sections=[
            fch.PieChartSection(
                value=40,
                title="40%",
                title_style=NORMAL_TITLE_STYLE,
                color=ft.Colors.BLUE,
                radius=NORMAL_RADIUS,
                badge=SectionBadge(ft.Icons.AC_UNIT),
                badge_position=0.98,
            ),
            fch.PieChartSection(
                value=30,
                title="30%",
                title_style=NORMAL_TITLE_STYLE,
                color=ft.Colors.YELLOW,
                radius=NORMAL_RADIUS,
                badge=SectionBadge(ft.Icons.ACCESS_ALARM),
                badge_position=0.98,
            ),
            fch.PieChartSection(
                value=15,
                title="15%",
                title_style=NORMAL_TITLE_STYLE,
                color=ft.Colors.PURPLE,
                radius=NORMAL_RADIUS,
                badge=SectionBadge(ft.Icons.APPLE),
                badge_position=0.98,
            ),
            fch.PieChartSection(
                value=15,
                title="15%",
                title_style=NORMAL_TITLE_STYLE,
                color=ft.Colors.GREEN,
                radius=NORMAL_RADIUS,
                badge=SectionBadge(ft.Icons.PEDAL_BIKE),
                badge_position=0.98,
            ),
        ],
    )

    page.add(chart)


ft.run(main)