bokeh.events#
Represent granular events that can be used to trigger callbacks.
Bokeh documents and applications are capable of supporting various kinds of interactions. These are often associated with events, such as mouse or touch events, interactive downsampling mode activation, widget or tool events, and others. The classes in this module represent these different events, so that callbacks can be attached and executed when they occur.
It is possible to respond to events with CustomJS
callbacks, which will
function with or without a Bokeh server. This can be accomplished by passing
and event class, and a CustomJS
model to the
js_on_event()
method. When the CustomJS
is
executed in the browser, its cb_obj
argument will contain the concrete
event object that triggered the callback.
from bokeh.events import ButtonClick
from bokeh.models import Button, CustomJS
button = Button()
button.js_on_event(ButtonClick, CustomJS(code='console.log("JS:Click")'))
Alternatively it is possible to trigger Python code to run when events
happen, in the context of a Bokeh application running on a Bokeh server.
This can be accomplished by passing an event class, and a callback function
to the on_event()
method. The callback should
accept a single argument event
, which will be passed the concrete
event object that triggered the callback.
from bokeh.events import ButtonClick
from bokeh.models import Button
button = Button()
def callback(event):
print('Python:Click')
button.on_event(ButtonClick, callback)
Note
There is no throttling of events. Some events such as MouseMove
may trigger at a very high rate.
- class ButtonClick(model: AbstractButton | None)[source]#
Announce a button click event on a Bokeh button widget.
- class ConnectionLost[source]#
Announce when a connection to the server/client was lost.
Note
To register a JS callback for this event in standalone embedding mode, one has to either use
curdoc()
or an explicitDocument
instance, e.g.:from bokeh.io import curdoc curdoc().js_on_event("document_ready", handler)
- class DocumentEvent[source]#
Base class for all Bokeh Document events.
This base class is not typically useful to instantiate on its own.
- class DocumentReady[source]#
Announce when a Document is fully idle.
Note
To register a JS callback for this event in standalone embedding mode, one has to either use
curdoc()
or an explicitDocument
instance, e.g.:from bokeh.io import curdoc curdoc().js_on_event("document_ready", handler)
- class DoubleTap(model: Plot | None, sx: float | None = None, sy: float | None = None, x: float | None = None, y: float | None = None, modifiers: KeyModifiers | None = None)[source]#
Announce a double-tap or double-click event on a Bokeh plot.
- class Event[source]#
Base class for all Bokeh events.
This base class is not typically useful to instantiate on its own.
- to_serializable(serializer: Serializer) BokehEventRep [source]#
Converts this object to a serializable representation.
- class LODEnd(model: Plot | None)[source]#
Announce the end of “interactive level-of-detail” mode on a plot.
During interactive actions such as panning or zooming, Bokeh can optionally, temporarily draw a reduced set of the data, in order to maintain high interactive rates. This is referred to as interactive Level-of-Detail (LOD) mode. This event fires whenever a LOD mode has just ended.
- class LODStart(model: Plot | None)[source]#
Announce the start of “interactive level-of-detail” mode on a plot.
During interactive actions such as panning or zooming, Bokeh can optionally, temporarily draw a reduced set of the data, in order to maintain high interactive rates. This is referred to as interactive Level-of-Detail (LOD) mode. This event fires whenever a LOD mode has just begun.
- class LegendItemClick(model: Legend, item: LegendItem)[source]#
Announce a click event on a Bokeh legend item.
- class MenuItemClick(model: Model, item: str | None = None)[source]#
Announce a button click event on a Bokeh menu item.
- class ModelEvent(model: Model | None)[source]#
Base class for all Bokeh Model events.
This base class is not typically useful to instantiate on its own.
- class MouseEnter(model: Plot | None, sx: float | None = None, sy: float | None = None, x: float | None = None, y: float | None = None, modifiers: KeyModifiers | None = None)[source]#
Announce a mouse enter event onto a Bokeh plot.
Note
The enter event is generated when the mouse leaves the entire Plot canvas, including any border padding and space for axes or legends.
- class MouseLeave(model: Plot | None, sx: float | None = None, sy: float | None = None, x: float | None = None, y: float | None = None, modifiers: KeyModifiers | None = None)[source]#
Announce a mouse leave event from a Bokeh plot.
Note
The leave event is generated when the mouse leaves the entire Plot canvas, including any border padding and space for axes or legends.
- class MouseMove(model: Plot | None, sx: float | None = None, sy: float | None = None, x: float | None = None, y: float | None = None, modifiers: KeyModifiers | None = None)[source]#
Announce a mouse movement event over a Bokeh plot.
Note
This event can fire at a very high rate, potentially increasing network traffic or CPU load.
- class MouseWheel(model: Plot | None, *, delta: float | None = None, sx: float | None = None, sy: float | None = None, x: float | None = None, y: float | None = None, modifiers: KeyModifiers | None = None)[source]#
Announce a mouse wheel event on a Bokeh plot.
Note
By default, Bokeh plots do not prevent default scroll events unless a
WheelZoomTool
orWheelPanTool
is active. This may change in future releases.
- class Pan(model: Plot | None, *, delta_x: float | None = None, delta_y: float | None = None, direction: Literal[-1, -1] | None = None, sx: float | None = None, sy: float | None = None, x: float | None = None, y: float | None = None, modifiers: KeyModifiers | None = None)[source]#
Announce a pan event on a Bokeh plot.
- class PanEnd(model: Plot | None, sx: float | None = None, sy: float | None = None, x: float | None = None, y: float | None = None, modifiers: KeyModifiers | None = None)[source]#
Announce the end of a pan event on a Bokeh plot.
- class PanStart(model: Plot | None, sx: float | None = None, sy: float | None = None, x: float | None = None, y: float | None = None, modifiers: KeyModifiers | None = None)[source]#
Announce the start of a pan event on a Bokeh plot.
- class Pinch(model: Plot | None, *, scale: float | None = None, sx: float | None = None, sy: float | None = None, x: float | None = None, y: float | None = None, modifiers: KeyModifiers | None = None)[source]#
Announce a pinch event on a Bokeh plot.
Note
This event is only applicable for touch-enabled devices.
- class PinchEnd(model: Plot | None, sx: float | None = None, sy: float | None = None, x: float | None = None, y: float | None = None, modifiers: KeyModifiers | None = None)[source]#
Announce the end of a pinch event on a Bokeh plot.
Note
This event is only applicable for touch-enabled devices.
- class PinchStart(model: Plot | None, sx: float | None = None, sy: float | None = None, x: float | None = None, y: float | None = None, modifiers: KeyModifiers | None = None)[source]#
Announce the start of a pinch event on a Bokeh plot.
Note
This event is only applicable for touch-enabled devices.
- class PlotEvent(model: Plot | None)[source]#
The base class for all events applicable to Plot models.
- class PointEvent(model: Plot | None, sx: float | None = None, sy: float | None = None, x: float | None = None, y: float | None = None, modifiers: KeyModifiers | None = None)[source]#
Base class for UI events associated with a specific (x,y) point.
Note that data space coordinates are relative to the default range, not any extra ranges, and the screen space origin is at the top left of the HTML canvas.
- class Press(model: Plot | None, sx: float | None = None, sy: float | None = None, x: float | None = None, y: float | None = None, modifiers: KeyModifiers | None = None)[source]#
Announce a press event on a Bokeh plot.
- class PressUp(model: Plot | None, sx: float | None = None, sy: float | None = None, x: float | None = None, y: float | None = None, modifiers: KeyModifiers | None = None)[source]#
Announce a pressup event on a Bokeh plot.
- class RangesUpdate(model: Plot | None, *, x0: float | None = None, x1: float | None = None, y0: float | None = None, y1: float | None = None)[source]#
Announce combined range updates in a single event.
Callbacks may be added to range
start
andend
properties to respond to range changes, but this can result in multiple callbacks being invoked for a single logical operation (e.g. a pan or zoom). This event is emitted by supported tools when the entire range update is complete, in order to afford a single event that can be responded to.
- class Rotate(model: Plot | None, *, rotation: float | None = None, sx: float | None = None, sy: float | None = None, x: float | None = None, y: float | None = None, modifiers: KeyModifiers | None = None)[source]#
Announce a rotate event on a Bokeh plot.
Note
This event is only applicable for touch-enabled devices.
- class RotateEnd(model: Plot | None, sx: float | None = None, sy: float | None = None, x: float | None = None, y: float | None = None, modifiers: KeyModifiers | None = None)[source]#
Announce the end of a rotate event on a Bokeh plot.
Note
This event is only applicable for touch-enabled devices.
- class RotateStart(model: Plot | None, sx: float | None = None, sy: float | None = None, x: float | None = None, y: float | None = None, modifiers: KeyModifiers | None = None)[source]#
Announce the start of a rotate event on a Bokeh plot.
Note
This event is only applicable for touch-enabled devices.
- class SelectionGeometry(model: Plot | None, geometry: GeometryData | None = None, final: bool = True)[source]#
Announce the coordinates of a selection event on a plot.