add self.fig.canvas.draw()
at the end of the run
function.
The point is slow to appear because an update isn't forced before you leave the button.
Вопрос
In my code, I have a draggablepoint class which defines a point that can be dragged interactively. So the interface basically selects one draggablepoint, clears the existing points and draws it on the figure. I expect the point to be shown on the figure right after I click the button, however, it takes time to show the point. Are there any faster ways to write the matplotlib part code? Thank you!
import matplotlib.pyplot as plt
import matplotlib.patches as patches
from matplotlib.widgets import Button
from random import randint
import math
class Interface:
def __init__(self, points):
self.points = points
self.fig = plt.figure()
self.ax = self.fig.add_subplot(111)
self.run_button = Button(plt.axes([0.75, 0.6, 0.1, 0.04]), 'Draw', color='g', hovercolor='0.75')
self.circles = []
self.has_circle = False
self.draggables = []
def go(self):
self.run_button.on_clicked(self.run)
def run(self, event):
'''remove point from the figure first'''
if self.has_circle:
self.circle.remove()
did = randint(0, len(self.points)-1)
self.has_circle = True
self.circle = patches.Circle(self.points[did], 0.02, fc='b', alpha=0.5, picker=True)
self.ax.add_patch(self.circle)
dr = DraggablePoint(self.circle)
dr.connect()
self.draggables.append(dr)
class DraggablePoint:
lock = None #only one can be animated at a time
def __init__(self, point):
self.point = point
self.press = None
self.background = None
self.ax = self.point.figure.add_subplot(111)
def connect(self):
'connect to all the events we need'
self.cidpress = self.point.figure.canvas.mpl_connect('button_press_event', self.on_press)
self.cidrelease = self.point.figure.canvas.mpl_connect('button_release_event', self.on_release)
self.cidmotion = self.point.figure.canvas.mpl_connect('motion_notify_event', self.on_motion)
def on_press(self, event):
if event.inaxes != self.point.axes: return
if DraggablePoint.lock is not None: return
contains = self.point.contains(event)[0]
if not contains: return
self.press = (self.point.center), event.xdata, event.ydata
DraggablePoint.lock = self
# draw everything but the selected rectangle and store the pixel buffer
canvas = self.point.figure.canvas
axes = self.point.axes
self.point.set_animated(True)
canvas.draw()
self.background = canvas.copy_from_bbox(self.point.axes.bbox)
# now redraw just the rectangle
axes.draw_artist(self.point)
# and blit just the redrawn area
canvas.blit(axes.bbox)
def on_motion(self, event):
if DraggablePoint.lock is not self: return
if event.inaxes != self.point.axes: return
if event.xdata < event.ydata / math.sqrt(3): return
if event.xdata > (event.ydata - math.sqrt(3))/(-math.sqrt(3)): return
self.point.center, xpress, ypress = self.press
dx = event.xdata - xpress
dy = event.ydata - ypress
self.point.center = (self.point.center[0]+dx, self.point.center[1]+dy)
canvas = self.point.figure.canvas
axes = self.point.axes
# restore the background region
canvas.restore_region(self.background)
# redraw just the current rectangle
axes.draw_artist(self.point)
# blit just the redrawn area
canvas.blit(axes.bbox)
def on_release(self, event):
'on release we reset the press data'
if DraggablePoint.lock is not self:return
self.press = None
DraggablePoint.lock = None
# turn off the rect animation property and reset the background
self.point.set_animated(False)
self.background = None
# redraw the full figure
self.point.figure.canvas.draw()
def disconnect(self):
'disconnect all the stored connection ids'
self.point.figure.canvas.mpl_disconnect(self.cidpress)
self.point.figure.canvas.mpl_disconnect(self.cidrelease)
self.point.figure.canvas.mpl_disconnect(self.cidmotion)
if __name__ == '__main__':
points = [(0.5,0.4), (0.2, 0.3), (0.4, 0.8), (0.8, 0.9)]
interface = Interface(points)
interface.go()
plt.show()
Решение
add self.fig.canvas.draw()
at the end of the run
function.
The point is slow to appear because an update isn't forced before you leave the button.