主题
CupertinoDatePicker 继承自: LayoutControl, Control, BaseControl
An iOS-styled date picker.
示例
python
from datetime import datetime
import flet as ft
def main(page: ft.Page):
page.horizontal_alignment = ft.CrossAxisAlignment.CENTER
message = ft.Text("Chosen Time:")
def handle_date_change(e: ft.Event[ft.CupertinoDatePicker]):
message.value = f"Chosen Date: {e.control.value.strftime('%Y-%m-%d %H:%M %p')}"
cupertino_date_picker = ft.CupertinoDatePicker(
value=datetime.now(),
date_picker_mode=ft.CupertinoDatePickerMode.DATE_AND_TIME,
on_change=handle_date_change,
)
page.add(
ft.SafeArea(
content=ft.Column(
horizontal_alignment=ft.CrossAxisAlignment.CENTER,
controls=[
ft.CupertinoFilledButton(
on_click=lambda _: page.show_dialog(
ft.CupertinoBottomSheet(
height=216,
padding=ft.Padding.only(top=6),
content=cupertino_date_picker,
)
),
content="Open CupertinoDatePicker",
),
message,
],
),
)
)
if __name__ == "__main__":
ft.run(main)
属性
| 名称 | 类型 | 默认值 | 说明 |
|---|---|---|---|
value | DateTimeValue | datetime.now(() | The initial date and/or time of the picker. Defaults to the present date and time. Raises: ValueError: If it is not greater than or equal to first_date, when first_date is set. ValueError: If it is not less than or equal to last_date, when last_date is set. ValueError: If its year is not greater than or equal to minimum_year, when date_picker_mode is DATE or MONTH_YEAR. ValueError: If its year is not less than or equal to maximum_year, when maximum_year is set. ValueError: If its minute is not a multiple of minute_interval. |
locale | Optional[Locale] | None | The locale for this date picker. It is intended for rare cases where this control should be localized differently from the rest of the page. Notes: - The locale must be supported by Flutter's global localization delegates; otherwise the override is ignored and the control uses the page or system locale. - If None (the default), the page or system locale is used. |
first_date | Optional[DateTimeValue] | None | The earliest allowable date that the user can select. - If set to None (the default), there is no lower date limit. - When not None, one can still scroll the picker to dates earlier than first_date, with the exception that the on_change will not be called. Once let go, the picker will scroll back to first_date. Note: In TIME mode, a time becomes unselectable if the datetime produced by combining that particular time and the date part of value is earlier than last_date. So typically, first_date needs to be set to a datetime that is on the same date as value. |
last_date | Optional[DateTimeValue] | None | The latest allowable date that the user can select. - If set to None (the default), there is no upper date limit. - When not None, one can still scroll the picker to dates later than last_date, with the exception that the on_change will not be called. Once let go, the picker will scroll back to last_date. Note: In TIME mode, a time becomes unselectable if the datetime produced by combining that particular time and the date part of value is later than last_date. So typically, last_date needs to be set to a datetime that is on the same date as value. |
bgcolor | Optional[ColorValue] | None | The background color of this date picker. |
minute_interval | Annotated[int, V.gt(0), V.factor_of(60)] | 1 | The granularity of the minutes spinner, if it is shown in the current date_picker_mode. Raises: ValueError: If it is not strictly greater than 0. ValueError: If it is not a factor of 60. |
minimum_year | int | 1 | Minimum year to which the picker can be scrolled when in DATE mode. Raises: ValueError: If it is greater than value year. |
maximum_year | Optional[int] | None | Maximum year to which the picker can be scrolled when in DATE mode. Defaults to None - no limit. Raises: ValueError: If it is less than value year. |
item_extent | Number | 32.0 | The uniform height of all children. Raises: ValueError: If it is not strictly greater than 0. |
use_24h_format | bool | False | Whether to use the 24-hour time format. If False, the 12-hour time format is used. |
show_day_of_week | bool | False | Whether to show day of week alongside day. Raises: ValueError: If it is set when date_picker_mode is not DATE. |
date_picker_mode | CupertinoDatePickerMode | CupertinoDatePickerMode.DATE_AND_TIME | The mode of the date picker. |
date_order | Optional[CupertinoDatePickerDateOrder] | None | The order in which the columns inside this picker are displayed. Note: The final order in which the columns are displayed is also influenced by the date_picker_mode. For example, if date_picker_mode is MONTH_YEAR both DAY_MONTH_YEAR and MONTH_DAY_YEAR will result in the `month\ |
width | Optional[Number] | None | Imposed Control width in virtual pixels. |
height | Optional[Number] | None | Imposed Control height in virtual pixels. |
left | Optional[Number] | 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, overlay list. |
top | Optional[Number] | 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, overlay list. |
right | Optional[Number] | 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, overlay list. |
bottom | Optional[Number] | 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, overlay list. |
align | Optional[Alignment] | None | Alignment of the control within its parent. |
margin | Optional[MarginValue] | None | Sets the margin of the control. |
rotate | Optional[RotateValue] | 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. Example: python 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) ) |
scale | Optional[ScaleValue] | 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. Example: python 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) ) |
offset | Optional[OffsetValue] | 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: python import flet as ft def main(page: ft.Page): page.add( ft.Stack( width=1000, height=1000, controls=[ ft.Container( bgcolor=ft.Colors.RED, width=100, height=100, left=100, top=100, offset=ft.Offset(-1, -1), ) ], ) ) ft.run(main) |
flip | Optional[Flip] | None | Flips this control horizontally and/or vertically. Set to an instance of Flip to mirror across x-axis, y-axis, or both. |
transform | Optional[Transform] | None | Applies a generic matrix transform to this control. Set to an instance of Transform with a recorded Matrix4 to describe arbitrary transform sequences. |
aspect_ratio | Optional[Number] | None | The aspect ratio of the control. It is defined as the ratio of width to height. Note: In current implementation, if aspect_ratio is set, width and height on the same control are ignored for final rendered size. |
animate_opacity | Optional[AnimationValue] | None | 启用 opacity 属性的隐式动画。 详见 此处. |
animate_size | Optional[AnimationValue] | None | 启用此控件尺寸的隐式动画。 If width or height is set, changes to those dimensions are animated. If neither dimension is set, changes to the control's natural size are animated instead. 详见 此处. |
animate_position | Optional[AnimationValue] | None | 启用定位属性(left、right、top、bottom)的隐式动画。 详见 此处. |
animate_align | Optional[AnimationValue] | None | 启用 align 属性的隐式动画。 详见 此处. |
animate_margin | Optional[AnimationValue] | None | 启用 margin 属性的隐式动画。 详见 此处. |
animate_rotation | Optional[AnimationValue] | None | 启用 rotate 属性的隐式动画。 详见 此处. |
animate_scale | Optional[AnimationValue] | None | 启用 scale 属性的隐式动画。 详见 此处. |
animate_offset | Optional[AnimationValue] | None | 启用 offset 属性的隐式动画。 详见 此处. |
size_change_interval | int | 10 | Sampling interval in milliseconds for on_size_change event. Setting to 0 calls on_size_change immediately on every change. |
expand | Annotated[Optional[Union[bool, int]], V.instance_of((bool, int))] | None | 指定此控件是否/如何扩展以填充父布局中的可用空间。 详见 此处. Note: Has effect only if the direct parent of this control is one of the following controls, or their subclasses: Column, Row, View, Page. Raises: ValueError: If it is not of type bool or int. |
expand_loose | bool | False | 允许控件在主轴方向上有可用空间时扩展,但不要求填满所有可用空间。 详见 此处. Note: 若 expand_loose 为 True,则仅当同时满足以下条件时生效: - expand 不为 None,且 - the direct parent of this control is one of the following controls, or their subclasses: Column, Row, View, Page. |
col | ResponsiveNumber | 12 | 若此控件的父控件是 ResponsiveRow,此属性用于决定该控件横跨多少个虚拟列。 可以是数字,也可以是为不同断点配置不同值的字典,例如 col={"sm": 6}。 0 表示在该断点下隐藏控件,不占用任何列。 默认横跨 12 个虚拟列。 \ |
opacity | Annotated[Number, V.between(0.0, 1.0)] | 1.0 | 定义控件的透明度,取值范围 0.0(完全透明)到 1.0(完全不透明)。 抛出异常:ValueError:若不在 0.0 到 1.0 的闭区间内。 |
tooltip | Optional[TooltipValue] | None | 鼠标悬停时显示的 tooltip。 |
badge | Optional[BadgeValue] | None | 显示在控件顶部的徽标。 |
visible | bool | True | Every control has visible property which is True by default - control is rendered on the page. Setting visible to False 完全阻止该控件(及其所有子控件)渲染到页面画布上. 隐藏的控件不能通过键盘或鼠标聚焦或选中,也不会触发任何事件。 |
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. Example: For example, if you have a form with multiple entry controls you can disable them all together by disabling container: python ft.Column( disabled = True, controls=[ ft.TextField(), ft.TextField() ] ) |
rtl | bool | False | 控件的文字方向是否为从右到左(RTL)。 |
data | Any | skip_ | 任意类型的自定义数据。 |
key | Optional['KeyValue'] | None | 用于在更新之间保持控件身份稳定的 key。 |
只读属性
| 名称 | 类型 | 默认值 | 说明 |
|---|---|---|---|
parent | Optional['BaseControl'] | — | 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). Page 控件(树的根)为例外 —— 它始终 parent=None。 |
page | 'Page' | — | 此控件所属的页面。 |
事件
| 名称 | 类型 | 默认值 | 说明 |
|---|---|---|---|
on_change | Optional[ControlEventHandler['CupertinoDatePicker']] | None | Called when the selected date and/or time changes. Will not be called if the new selected value is not valid, or is not in the range of first_date and last_date. |
on_size_change | Optional[EventHandler[LayoutSizeChangeEvent['LayoutControl']]] | None | Called when the size of this control changes. size_change_interval defines how often this event is called. |
on_animation_end | Optional[ControlEventHandler['LayoutControl']] | None | 动画结束时调用,可用于串联多个动画。 事件参数 data 属性包含动画的名称。 详见 此处. |
方法
| 名称 | 类型 | 默认值 | 说明 |
|---|---|---|---|
before_update | — | — | — |
is_isolated | — | — | Return whether this control is marked as isolated. 被隔离的控件不会参与父级驱动的更新遍历,需要自行管理更新边界。 |
init | — | — | Called after control instance initialization and before the first build / update cycle. 可重写此钩子执行依赖于已初始化字段的轻量设置。 不要在这里调用 update()。 |
build | — | — | 在控件初始化期间调用一次,用于定义其子控件。 page 属性在此方法中可用。 |
before_event | — | — | 在事件处理器执行前拦截事件。 返回 False 取消分发,返回 True 或 None 则继续正常的事件处理。 |
did_mount | — | — | 在控件挂载到页面树之后调用。 可重写以启动需要已挂载页面的资源,例如订阅、定时器或服务监听。 |
will_unmount | — | — | 在控件从页面树移除之前调用。 可重写以释放 did_mount() 中创建的资源,例如订阅、定时器或外部句柄。 |
get_data_channel | — | — | Resolve the [DataChannel] allocated on the Dart side for this widget. Pattern: on_data_channel_open: Optional[ft.EventHandler[DataChannelOpenEvent]] = None def init(self): self.on_data_channel_open = self._on_open def _on_open(self, e): self._channel = self.get_data_channel(e.channel_id) Idempotent — the underlying Connection caches DataChannels by id, so repeated calls return the same instance. No error path: the id always comes from a framework-fired event, so by the time this runs the channel exists on both sides. |
update | None | — | 请求更新该控件的 UI。 在修改控件状态或属性后调用。 控件必须已挂载到页面,并且未被冻结。 |