def new_timer(self, *args, **kwargs):
"""
Creates a new backend-specific subclass of :class:`backend_bases.Timer`.
This is useful for getting periodic events through the backend's native
event loop. Implemented only for backends with GUIs.
optional arguments:
*interval*
Timer interval in milliseconds
*callbacks*
Sequence of (func, args, kwargs) where func(*args, **kwargs) will
be executed by the timer every *interval*.
"""
return TimerTk(self._tkcanvas, *args, **kwargs)
python类backend_bases()的实例源码
def new_timer(self, *args, **kwargs):
"""
Creates a new backend-specific subclass of :class:`backend_bases.Timer`.
This is useful for getting periodic events through the backend's native
event loop. Implemented only for backends with GUIs.
optional arguments:
*interval*
Timer interval in milliseconds
*callbacks*
Sequence of (func, args, kwargs) where func(*args, **kwargs) will
be executed by the timer every *interval*.
"""
return TimerTk(self._tkcanvas, *args, **kwargs)
def _update_pointer_position(self, guiEvent=None):
"""
Figure out if we are inside the canvas or not and update the
canvas enter/leave events
"""
# if the pointer if over the canvas, set the lastx and lasty
# attrs of the canvas so it can process event w/o mouse click
# or move
# the window's upper, left coords in screen coords
xw = self._tkcanvas.winfo_rootx()
yw = self._tkcanvas.winfo_rooty()
# the pointer's location in screen coords
xp, yp = self._tkcanvas.winfo_pointerxy()
# not figure out the canvas coordinates of the pointer
xc = xp - xw
yc = yp - yw
# flip top/bottom
yc = self.figure.bbox.height - yc
# JDH: this method was written originally to get the pointer
# location to the backend lastx and lasty attrs so that events
# like KeyEvent can be handled without mouse events. e.g., if
# the cursor is already above the axes, then key presses like
# 'g' should toggle the grid. In order for this to work in
# backend_bases, the canvas needs to know _lastx and _lasty.
# There are three ways to get this info the canvas:
#
# 1) set it explicity
#
# 2) call enter/leave events explicity. The downside of this
# in the impl below is that enter could be repeatedly
# triggered if thes mouse is over the axes and one is
# resizing with the keyboard. This is not entirely bad,
# because the mouse position relative to the canvas is
# changing, but it may be surprising to get repeated entries
# without leaves
#
# 3) process it as a motion notify event. This also has pros
# and cons. The mouse is moving relative to the window, but
# this may surpise an event handler writer who is getting
# motion_notify_events even if the mouse has not moved
# here are the three scenarios
if 1:
# just manually set it
self._lastx, self._lasty = xc, yc
elif 0:
# alternate implementation: process it as a motion
FigureCanvasBase.motion_notify_event(self, xc, yc, guiEvent)
elif 0:
# alternate implementation -- process enter/leave events
# instead of motion/notify
if self.figure.bbox.contains(xc, yc):
self.enter_notify_event(guiEvent, xy=(xc,yc))
else:
self.leave_notify_event(guiEvent)
def _update_pointer_position(self, guiEvent=None):
"""
Figure out if we are inside the canvas or not and update the
canvas enter/leave events
"""
# if the pointer if over the canvas, set the lastx and lasty
# attrs of the canvas so it can process event w/o mouse click
# or move
# the window's upper, left coords in screen coords
xw = self._tkcanvas.winfo_rootx()
yw = self._tkcanvas.winfo_rooty()
# the pointer's location in screen coords
xp, yp = self._tkcanvas.winfo_pointerxy()
# not figure out the canvas coordinates of the pointer
xc = xp - xw
yc = yp - yw
# flip top/bottom
yc = self.figure.bbox.height - yc
# JDH: this method was written originally to get the pointer
# location to the backend lastx and lasty attrs so that events
# like KeyEvent can be handled without mouse events. e.g., if
# the cursor is already above the axes, then key presses like
# 'g' should toggle the grid. In order for this to work in
# backend_bases, the canvas needs to know _lastx and _lasty.
# There are three ways to get this info the canvas:
#
# 1) set it explicity
#
# 2) call enter/leave events explicity. The downside of this
# in the impl below is that enter could be repeatedly
# triggered if thes mouse is over the axes and one is
# resizing with the keyboard. This is not entirely bad,
# because the mouse position relative to the canvas is
# changing, but it may be surprising to get repeated entries
# without leaves
#
# 3) process it as a motion notify event. This also has pros
# and cons. The mouse is moving relative to the window, but
# this may surpise an event handler writer who is getting
# motion_notify_events even if the mouse has not moved
# here are the three scenarios
if 1:
# just manually set it
self._lastx, self._lasty = xc, yc
elif 0:
# alternate implementation: process it as a motion
FigureCanvasBase.motion_notify_event(self, xc, yc, guiEvent)
elif 0:
# alternate implementation -- process enter/leave events
# instead of motion/notify
if self.figure.bbox.contains(xc, yc):
self.enter_notify_event(guiEvent, xy=(xc,yc))
else:
self.leave_notify_event(guiEvent)
