Skip to content

BarChart

BarChart #

Bases: ConstrainedControl

Draws a bar chart.

Overview

animate_offset #

animate_offset: AnimationValue | None = None

Enables implicit animation of the offset property.

More information here.

animate_opacity #

animate_opacity: AnimationValue | None = None

Enables implicit animation of the opacity property.

More information here.

animate_position #

animate_position: AnimationValue | None = None

Enables implicit animation of the positioning properties (left, right, top and bottom).

More information here.

animate_rotation #

animate_rotation: AnimationValue | None = None

Enables implicit animation of the rotate property.

More information here.

animate_scale #

animate_scale: AnimationValue | None = None

Enables implicit animation of the scale property.

More information here.

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: Number | None = None

TBD

badge #

badge: BadgeValue | None = None

A badge to show on top of this control.

baseline_y #

baseline_y: Number | None = None

Baseline value for Y axis.

bgcolor #

bgcolor: ColorValue | None = None

Background color of the chart.

border #

border: Border | None = None

The border around the chart.

bottom #

bottom: Number | None = None

The distance that the child's bottom edge is inset from the bottom of the stack.

Note

Effective only if this control is a descendant of one of the following: Stack control, Page.overlay list.

bottom_axis #

bottom_axis: ChartAxis = field(
    default_factory=lambda: ChartAxis(label_size=30)
)

The appearance of the bottom axis, its title and labels.

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.

/// details | Dimensions type: info | 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.

/// details | Example type: 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()
    ]
)
///

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.

groups #

groups: list[BarChartGroup] = field(default_factory=list)

The list of BarChartGroups to draw.

height #

height: Number | None = None

Imposed Control height in virtual pixels.

horizontal_grid_lines #

horizontal_grid_lines: ChartGridLines | None = None

Controls drawing of chart's horizontal lines.

interactive #

interactive: bool = True

Enables automatic tooltips when hovering chart bars.

key #

key: KeyValue | None = None

left #

left: Number | None = None

The distance that the child's left edge is inset from the left of the stack.

Note

Effective only if this control is a descendant of one of the following: Stack control, Page.overlay list.

left_axis #

left_axis: ChartAxis = field(
    default_factory=lambda: ChartAxis(label_size=44)
)

The appearance of the left axis, its title and labels.

max_y #

max_y: Number | None = None

The maximum displayed value for Y axis.

min_y #

min_y: Number | None = None

The minimum displayed value for Y axis.

offset #

offset: OffsetValue | None = None

Applies a translation transformation before painting the control.

The translation is expressed as an Offset scaled to the control's size. So, Offset(x=0.25, y=0), for example, will result in a horizontal translation of one quarter the width of this control.

/// details | Example type: example The following example displays container at 0, 0 top left corner of a stack as transform applies -1 * 100, -1 * 100 (offset * control's size) horizontal and vertical translations to the control:

import flet as ft

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

ft.run(main)
///

on_animation_end #

on_animation_end: (
    ControlEventHandler[ConstrainedControl] | None
) = None

Called when animation completes.

Can be used to chain multiple animations.

The data property of the event handler argument contains the name of the animation.

More information here.

on_event #

on_event: EventHandler[BarChartEvent] | None = None

Fires when a bar 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).

page #

page: Page | BasePage | None

The page 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: Number | None = None

The distance that the child's right edge is inset from the right of the stack.

Note

Effective only if this control is a descendant of one of the following: Stack control, Page.overlay list.

right_axis #

right_axis: ChartAxis = field(
    default_factory=lambda: ChartAxis(label_size=44)
)

The appearance of the right axis, its title and labels.

rotate #

rotate: RotateValue | None = None

Transforms this control using a rotation around its 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.
  • Rotate - allows to specify rotation angle as well as alignment - the location of rotation center.

/// details | Example type: example 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

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

scale #

scale: ScaleValue | None = None

Scales this control along the 2D plane. Default scale factor is 1.0, meaning no-scale.

Setting this property to 0.5, for example, makes this control twice smaller, while 2.0 makes it twice larger.

Different scale multipliers can be specified for x and y axis, by setting Control.scale property to an instance of Scale class. Either scale or scale_x and scale_y could be specified, but not all of them.

/// details | Example type: example 

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

spacing #

spacing: Number | None = None

A amount of space between bar groups.

tooltip #

tooltip: BarChartTooltip | None = None

The tooltip configuration for the chart.

top #

top: Number | None = None

The distance that the child's top edge is inset from the top of the stack.

Note

Effective only if this control is a descendant of one of the following: Stack control, Page.overlay list.

top_axis #

top_axis: ChartAxis = field(
    default_factory=lambda: ChartAxis(label_size=30)
)

The appearance of the top axis, its title and labels.

vertical_grid_lines #

vertical_grid_lines: ChartGridLines | None = None

Controls drawing of chart's vertical lines.

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: Number | None = None

Imposed Control width in virtual pixels.

before_event #

before_event(e: ControlEvent)

before_update #

before_update()

build #

build()

Called once during control initialization to define its child controls. self.page is available in this method.

clean #

clean() -> None

did_mount #

did_mount()

init #

init()

is_isolated #

is_isolated()

update #

update() -> None

will_unmount #

will_unmount()

Examples#

Example 1#

BarChart example 1

import flet as ft

import flet_charts as fch


def main(page: ft.Page):
    page.add(
        fch.BarChart(
            expand=True,
            interactive=True,
            max_y=110,
            border=ft.Border.all(1, ft.Colors.GREY_400),
            horizontal_grid_lines=fch.ChartGridLines(
                color=ft.Colors.GREY_300, width=1, dash_pattern=[3, 3]
            ),
            tooltip=fch.BarChartTooltip(
                bgcolor=ft.Colors.with_opacity(0.5, ft.Colors.GREY_300),
                border_radius=ft.BorderRadius.all(20),
            ),
            left_axis=fch.ChartAxis(
                label_size=40, title=ft.Text("Fruit supply"), title_size=40
            ),
            right_axis=fch.ChartAxis(show_labels=False),
            bottom_axis=fch.ChartAxis(
                label_size=40,
                labels=[
                    fch.ChartAxisLabel(
                        value=0, label=ft.Container(ft.Text("Apple"), padding=10)
                    ),
                    fch.ChartAxisLabel(
                        value=1, label=ft.Container(ft.Text("Blueberry"), padding=10)
                    ),
                    fch.ChartAxisLabel(
                        value=2, label=ft.Container(ft.Text("Cherry"), padding=10)
                    ),
                    fch.ChartAxisLabel(
                        value=3, label=ft.Container(ft.Text("Orange"), padding=10)
                    ),
                ],
            ),
            groups=[
                fch.BarChartGroup(
                    x=0,
                    rods=[
                        fch.BarChartRod(
                            from_y=0,
                            to_y=40,
                            width=40,
                            color=ft.Colors.GREEN,
                            border_radius=0,
                        ),
                    ],
                ),
                fch.BarChartGroup(
                    x=1,
                    rods=[
                        fch.BarChartRod(
                            from_y=0,
                            to_y=100,
                            width=40,
                            color=ft.Colors.BLUE,
                            tooltip=fch.BarChartRodTooltip("Blueberry"),
                            border_radius=0,
                        ),
                    ],
                ),
                fch.BarChartGroup(
                    x=2,
                    rods=[
                        fch.BarChartRod(
                            from_y=0,
                            to_y=30,
                            width=40,
                            color=ft.Colors.RED,
                            border_radius=0,
                        ),
                    ],
                ),
                fch.BarChartGroup(
                    x=3,
                    rods=[
                        fch.BarChartRod(
                            from_y=0,
                            to_y=60,
                            width=40,
                            color=ft.Colors.ORANGE,
                            tooltip=fch.BarChartRodTooltip("Orange"),
                            border_radius=0,
                        ),
                    ],
                ),
            ],
        )
    )


ft.run(main)

Example 2#

BarChart example 2

import flet as ft

import flet_charts as fch


class CustomRod(fch.BarChartRod):
    def __init__(self, y: float, hovered: bool = False):
        super().__init__()
        self.hovered = hovered
        self.y = y
        self.width = 22
        self.color = ft.Colors.WHITE
        self.bg_to_y = 20
        self.bg_color = ft.Colors.GREEN_300

    def before_update(self):
        super().before_update()
        self.to_y = self.y + 0.5 if self.hovered else self.y
        self.color = ft.Colors.YELLOW if self.hovered else ft.Colors.WHITE
        self.border_side = (
            ft.BorderSide(width=1, color=ft.Colors.RED)
            if self.hovered
            else ft.BorderSide(width=1, color=ft.Colors.BLUE)
        )


def main(page: ft.Page):
    def on_chart_event(e: fch.BarChartEvent):
        if e.type == fch.ChartEventType.POINTER_HOVER:
            for group_index, group in enumerate(chart.groups):
                for rod_index, rod in enumerate(group.rods):
                    rod.hovered = (
                        e.group_index == group_index and e.rod_index == rod_index
                    )
            chart.update()

    chart = fch.BarChart(
        on_event=on_chart_event,
        interactive=True,
        groups=[
            fch.BarChartGroup(x=0, rods=[CustomRod(5)]),
            fch.BarChartGroup(x=1, rods=[CustomRod(6.5)]),
            fch.BarChartGroup(x=2, rods=[CustomRod(15)]),
            fch.BarChartGroup(x=3, rods=[CustomRod(7.5)]),
            fch.BarChartGroup(x=4, rods=[CustomRod(9)]),
            fch.BarChartGroup(x=5, rods=[CustomRod(11.5)]),
            fch.BarChartGroup(x=6, rods=[CustomRod(6)]),
        ],
        bottom_axis=fch.ChartAxis(
            labels=[
                fch.ChartAxisLabel(value=0, label=ft.Text("M", color=ft.Colors.BLUE)),
                fch.ChartAxisLabel(value=1, label=ft.Text("T", color=ft.Colors.YELLOW)),
                fch.ChartAxisLabel(value=2, label=ft.Text("W", color=ft.Colors.BLUE)),
                fch.ChartAxisLabel(value=3, label=ft.Text("T", color=ft.Colors.YELLOW)),
                fch.ChartAxisLabel(value=4, label=ft.Text("F", color=ft.Colors.BLUE)),
                fch.ChartAxisLabel(value=5, label=ft.Text("S", color=ft.Colors.YELLOW)),
                fch.ChartAxisLabel(value=6, label=ft.Text("S", color=ft.Colors.BLUE)),
            ],
        ),
    )

    page.add(
        ft.Container(
            content=chart,
            bgcolor=ft.Colors.GREEN_200,
            padding=10,
            border_radius=5,
            expand=True,
        )
    )


ft.run(main)