View
View
#
Bases: ScrollableControl
, ConstrainedControl
View is the top most container for all other controls.
A root view is automatically created when a new user session started. From layout
perspective the View represents a Column
control, so it has a similar behavior and shares same properties.
animate_offset
#
animate_offset: AnimationValue | None = None
animate_opacity
#
animate_opacity: AnimationValue | None = None
animate_position
#
animate_position: AnimationValue | None = None
animate_rotation
#
animate_rotation: AnimationValue | None = None
animate_scale
#
animate_scale: AnimationValue | None = None
appbar
#
appbar: AppBar | CupertinoAppBar | None = None
An AppBar
control to display at the top of
the Page
.
auto_scroll
#
auto_scroll: bool = False
True
if scrollbar should automatically move its position to the end when children
updated. Must be False
for scroll_to()
method to work.
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_appbar
#
bottom_appbar: BottomAppBar | None = None
A BottomAppBar
control to display at the bottom of
the Page
.
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.
Dimensions
Breakpoint | Dimension |
---|---|
xs | <576px |
sm | ≥576px |
md | ≥768px |
lg | ≥992px |
xl | ≥1200px |
xxl | ≥1400px |
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.
drawer
#
drawer: NavigationDrawer | None = None
A NavigationDrawer
control to
display as a panel sliding from the start edge of the view.
end_drawer
#
end_drawer: NavigationDrawer | None = None
A NavigationDrawer
control to
display as a panel sliding from the end edge of the view.
expand
#
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.
floating_action_button
#
floating_action_button: FloatingActionButton | None = None
A FloatingActionButton
control to display on top of Page
content.
floating_action_button_location
#
floating_action_button_location: (
FloatingActionButtonLocation | OffsetValue | None
) = None
Describes position of floating_action_button
foreground_decoration
#
foreground_decoration: BoxDecoration | None = None
The foreground decoration.
horizontal_alignment
#
horizontal_alignment: CrossAxisAlignment = START
How the child Controls should be placed horizontally.
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.
navigation_bar
#
navigation_bar: (
NavigationBar | CupertinoNavigationBar | None
) = None
A navigation bar (NavigationBar
or
CupertinoNavigationBar
) control to display
at the bottom of the Page
.
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.
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:
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_scroll
#
on_scroll: EventHandler[OnScrollEvent] | None = None
Called when scroll position is changed by a user. class.
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).
padding
#
padding: PaddingValue | None = field(
default_factory=lambda: all(10)
)
A space between page contents and its edges.
page
#
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: 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.
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 circle360°
ismath.pi * 2
radians,90°
ispi / 2
,45°
ispi / 4
, etc.Rotate
- allows to specify rotationangle
as well asalignment
- the location of rotation center.
route
#
route: str | None = None
View's route - not currently used by Flet framework, but can be used in a user
program to update Page.route
when a view popped.
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.
scroll
#
scroll: ScrollMode | None = None
Enables a vertical scrolling for the Column to prevent its content overflow.
Defaults to ScrollMode.None
.
spacing
#
spacing: Number = 10
The vertical spacing between controls
on the Page
.
Note
Has effect only when vertical_alignment
is set to
MainAxisAlignment.START
,
MainAxisAlignment.END
,
or MainAxisAlignment.CENTER
.
tooltip
#
tooltip: TooltipValue | None = None
The tooltip ot show when this control is hovered over.
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.
vertical_alignment
#
vertical_alignment: MainAxisAlignment = START
Defines how the child controls
should be placed vertically.
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.
scroll_to
#
scroll_to(
offset: Number | None = None,
delta: Number | None = None,
scroll_key: str
| int
| float
| bool
| ScrollKey
| None = None,
duration: DurationValue | None = None,
curve: AnimationCurve | None = None,
)
Moves scroll position to either absolute offset
, relative delta
or jump to
the control with specified key
.
offset
is an absolute value between minimum and maximum extents of a
scrollable control, for example:
offset
could be a negative to scroll from the end of a scrollable. For
example, to scroll to the very end:
delta
allows moving scroll relatively to the current position. Use positive
delta
to scroll forward and negative delta
to scroll backward. For example,
to move scroll on 50 pixels forward:
key
allows moving scroll position to a control with specified key
. Most of
Flet controls have key
property which is translated to Flutter as
"global key". key
must be unique for the entire page/view. For example:
import flet as ft
def main(page: ft.Page):
cl = ft.Column(
spacing=10,
height=200,
width=200,
scroll=ft.ScrollMode.ALWAYS,
)
for i in range(0, 50):
cl.controls.append(ft.Text(f"Text line {i}", key=str(i)))
def scroll_to_key(e):
cl.scroll_to(key="20", duration=1000)
page.add(
ft.Container(cl, border=ft.border.all(1)),
ft.ElevatedButton("Scroll to key '20'", on_click=scroll_to_key),
)
ft.run(main)
Note
scroll_to()
method won't work with ListView
and GridView
controls
building their items dynamically.
duration
is scrolling animation duration in milliseconds. Defaults to 0
-
no animation.
curve
configures animation curve. Property value is AnimationCurve
enum.
Defaults to AnimationCurve.EASE
.
scroll_to_async
#
scroll_to_async(
offset: float | None = None,
delta: float | None = None,
scroll_key: str
| int
| float
| bool
| ScrollKey
| None = None,
duration: DurationValue | None = None,
curve: AnimationCurve | None = None,
)
Moves scroll position to either absolute offset
, relative delta
or jump to
the control with specified key
.
offset
is an absolute value between minimum and maximum extents of a
scrollable control, for example:
offset
could be a negative to scroll from the end of a scrollable. For
example, to scroll to the very end:
delta
allows moving scroll relatively to the current position. Use positive
delta
to scroll forward and negative delta
to scroll backward. For example,
to move scroll on 50 pixels forward:
key
allows moving scroll position to a control with specified key
. Most of
Flet controls have key
property which is translated to Flutter as
"global key". key
must be unique for the entire page/view. For example:
import flet as ft
def main(page: ft.Page):
cl = ft.Column(
spacing=10,
height=200,
width=200,
scroll=ft.ScrollMode.ALWAYS,
)
for i in range(0, 50):
cl.controls.append(ft.Text(f"Text line {i}", key=str(i)))
def scroll_to_key(e):
cl.scroll_to(key="20", duration=1000)
page.add(
ft.Container(cl, border=ft.border.all(1)),
ft.ElevatedButton("Scroll to key '20'", on_click=scroll_to_key),
)
ft.run(main)
Note
scroll_to()
method won't work with ListView
and GridView
controls
building their items dynamically.
duration
is scrolling animation duration in milliseconds. Defaults to 0
-
no animation.
curve
configures animation curve. Property value is AnimationCurve
enum.
Defaults to AnimationCurve.EASE
.