问题描述
我想使用PyQt5为图制作动画,以便垂直线会随着时间在整个图形上滚动。 为了实现这一点,我开始修改this neat LearnPyQt tutorial中提供的代码示例。 到目前为止,我能够使用以下命令在用户定义的横坐标上绘制一条垂直线:
self.canvas.axes.axvline(x=5)
如果我使用的是for
循环,我只会基于索引更新x,但是在这种情况下,我无法确定如何根据计时器ID更新x。如何恢复该值并将其传递到我的update_plot
函数中?
到目前为止,这是我的代码:
import sys
import random
import matplotlib
matplotlib.use('Qt5Agg')
import pdb
from PyQt5 import QtCore,QtWidgets
from matplotlib.backends.backend_qt5agg import figureCanvasQTAgg as figureCanvas
from matplotlib.figure import figure
class MplCanvas(figureCanvas):
def __init__(self,parent=None,width=5,height=4,dpi=100):
fig = figure(figsize=(width,height),dpi=dpi)
self.axes = fig.add_subplot(111)
super(MplCanvas,self).__init__(fig)
class MainWindow(QtWidgets.QMainWindow):
def __init__(self,*args,**kwargs):
super(MainWindow,self).__init__(*args,**kwargs)
self.canvas = MplCanvas(self,dpi=100)
self.setCentralWidget(self.canvas)
self.timer_id = 0
n_data = 50
self.xdata = list(range(n_data))
self.ydata = [random.randint(0,10) for i in range(n_data)]
self.update_plot()
self.show()
self.timer = QtCore.QTimer()
self.timer.setInterval(100)
self.timer.timeout.connect(self.update_plot)
self.timer.start()
def update_plot(self):
self.canvas.axes.plot(self.xdata,self.ydata,'r')
self.canvas.axes.axvline(x=5)
self.canvas.draw()
app = QtWidgets.QApplication(sys.argv)
w = MainWindow()
app.exec_()
解决方法
如果保留对axvline(Line2D对象)的引用,则可以调用set_xdata
并在调用self.timer_id
时使update_plot
递增以沿图中的直线移动。
class MainWindow(QtWidgets.QMainWindow):
def __init__(self,*args,**kwargs):
super(MainWindow,self).__init__(*args,**kwargs)
self.canvas = MplCanvas(self,width=5,height=4,dpi=100)
self.setCentralWidget(self.canvas)
self.timer_id = 0
n_data = 50
self.xdata = list(range(n_data))
self.ydata = [random.randint(0,10) for i in range(n_data)]
self.update_plot()
self.show()
self.timer = QtCore.QTimer()
self.timer.setInterval(100)
self.timer.timeout.connect(self.update_plot)
self.timer.start()
def update_plot(self):
if not self.timer_id:
self.canvas.axes.plot(self.xdata,self.ydata,'r')
self.vline = self.canvas.axes.axvline(x=self.timer_id)
else:
self.vline.set_xdata(self.timer_id)
self.canvas.draw()
self.timer_id += 1