我试图在Kivy中将matplotlib与折线图一起使用，当鼠标悬停在图表的各个点上时，该折线图会弹出交互式数据标签。我知道可以根据以下示例在matplotlib中完成此操作：Possible to make labels appear when hovering over a point in matplotlib?
将Kivy与matplotlib一起使用时，尝试使用此事件时出现错误：
self.fig.canvas.mpl_connect（“ motion_notify_event”，悬停）
错误：“ NameError：未定义名称悬停”
import kivy
import matplotlib
matplotlib.use('module://kivy.garden.matplotlib.backend_kivy')
import matplotlib.pyplot as plt
from kivy.garden.matplotlib import FigureCanvasKivyAgg
from matplotlib.ticker import (MultipleLocator, FormatStrFormatter,
AutoMinorLocator)
from kivy.app import App
from kivy.uix.boxlayout import BoxLayout
from kivy.uix.floatlayout import FloatLayout
from kivy.uix.button import Button
from kivy.uix.label import Label
from kivy.properties import BooleanProperty, ListProperty, StringProperty,
ObjectProperty
from kivy.lang import Builder
class testApp(App):
def __init__(self, **kwargs):
super(testApp, self).__init__(**kwargs)
def hover(event):
# code to track the mouse position within the matplotlib chart and
figure out what point in the chart it is hovering over, then display
the popup_label defined below
pass
def build(self):
mylayout = FloatLayout()
# create the matplot lib chart and add it to the kivy float layout
self.fig,self.ax = plt.subplots(1)
self.plt_canvas = self.fig.canvas
mylayout.add_widget(self.plt_canvas)
# load x and y axis data into variables and use in chart
year = [1960, 1970, 1980, 1990, 2000, 2010]
pop_pakistan = [44.91, 58.09, 78.07, 107.7, 138.5, 170.6]
pop_india = [449.48, 553.57, 696.783, 870.133, 1000.4, 1309.1]
# set line colors
plt.plot(year, pop_pakistan, color='g')
plt.plot(year, pop_india, color='orange')
# set x and y axis labels and chart title
plt.xlabel('Countries')
plt.ylabel('Population in million')
plt.title('Pakistan India Population till 2010')
# set minor ticks as a multiple of 2
minorLocator = MultipleLocator(2)
self.ax.xaxis.set_minor_locator(minorLocator)
# create a test popup matplotlib chart label
popup_label = self.ax.annotate("(1970, 45)", xy=(1970,70))
popup_label.set_visible(True) #popup label works on the chart as an
example. this would be triggered in the def(hover) event above when
mouse hovers over a point..
self.fig.canvas.mpl_connect("motion_notify_event", hover) #CODE
ERRORS HERE - CAN'T RECOGNIZED HOVER
return mylayout
if __name__ == '__main__':
testApp().run()
答案 0 :(得分：0)
我想出了如何在将鼠标移到图表的各个点上时显示弹出标签。这是对我有用的东西：
import kivy
import time
import matplotlib
matplotlib.use('module://kivy.garden.matplotlib.backend_kivy')
import matplotlib.pyplot as plt
from kivy.garden.matplotlib import FigureCanvasKivyAgg
from matplotlib.ticker import (MultipleLocator, FormatStrFormatter, AutoMinorLocator)
from kivy.app import App
from kivy.uix.boxlayout import BoxLayout
from kivy.uix.floatlayout import FloatLayout
from kivy.uix.button import Button
from kivy.uix.label import Label
from kivy.properties import BooleanProperty, ListProperty, StringProperty,
ObjectProperty
from kivy.core.window import Window
class testyApp(App):
def __init__(self, **kwargs):
super(testyApp, self).__init__(**kwargs)
def build(self):
global line1
global x
global y
global popup_label
# create the matplotlib chart and add it to the kivy float layout
mylayout = FloatLayout()
self.fig = plt.figure()
self.ax = plt.axes()
self.plt_canvas = self.fig.canvas
mylayout.add_widget(self.plt_canvas)
# load x and y axis data into variables and plot the points in the
chart
xv = 0
yv = 0
x = []
y = []
for i in range(0, 31):
xv = xv + 1
yv = yv + 10
x.append(xv)
y.append(yv)
line1, = plt.plot(x, y)
# set x and y axis labels and chart title
plt.xlabel('Countries')
plt.ylabel('Population in million')
plt.title('Pakistan Population till 2010')
# enable mouse hover event
self.fig.canvas.mpl_connect("motion_notify_event", self.mouse_hover)
# create starting label and make it invisible
popup_label = self.ax.annotate("", xy=(0, 0), xytext=(0, 0))
popup_label.set_visible(False)
return mylayout
def show_popup_label(self):
# changes the coordinates and text of the popup label and makes it
# visible when the mouse hovers over a point on the line..
text = "(" + str(found_x) + ", " + str(found_y) + ")"
popup_label.set_text(text)
popup_label.set_position((found_x, found_y))
popup_label.set_visible(True)
self.fig.canvas.draw()
def hide_popup_label(self):
# hides the popup label when the mouse is NOT on a point on the line
popup_label.set_visible(False)
self.fig.canvas.draw()
def mouse_hover(self, event):
# mouse hover event to track position of mouse on matplotlib chart
# and trigger show/hide popup label tasks
global found_x
global found_y
xd, yd = event.xdata, event.ydata
active, ind = line1.contains(event) # check to see if the mouse is
# hovering over any of the points on the line..
if active: # if the mouse is hovering over a point on the line
# then..
pos = str([ind["ind"][0]]) # fetch the array position of the
# point..
pos = pos.replace("[", "")
pos = pos.replace("]", "")
found_x = x[int(pos)] # use the array position to figure out its
# x and y cordinates that we stored in the x and y lists above..
found_y = y[int(pos)]
self.show_popup_label()
else: # if the mouse is NOT hovering over a point on the line then..
self.hide_popup_label()
if __name__ == '__main__':
testyApp().run()