Marker 继承自： ft.BaseControl

A marker displayed on the Map at the specified location through the MarkerLayer.

属性

名称	类型	默认值	说明
content	ft.Control	required	The content to be displayed at coordinates. Raises: ValueError: If it is not visible.
coordinates	MapLatitudeLongitude	required	The coordinates of the marker. This will be the center of the marker, if alignment is CENTER.
rotate	Optional[bool]	None	Whether to counter rotate this marker to the map's rotation, to keep a fixed orientation. So, when True, this marker will always appear upright and vertical from the user's perspective. If None, defaults to the value of the parent rotate. Note: This is not used to apply a custom rotation in degrees to this marker.
height	ft.Number	30.0	The height of the content Control. Raises: ValueError: If it is less than 0.0.
width	ft.Number	30.0	The width of the content Control. Raises: ValueError: If it is less than 0.0.
alignment	Optional[ft.Alignment]	None	Alignment of the marker relative to the normal center at coordinates. Defaults to the value of the parent alignment.
visible	bool	True	Whether this marker is rendered on the map.
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。

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。