import sys
import random

import matplotlib
matplotlib.use("Qt5Agg")

from PyQt5 import QtCore
from PyQt5.QtWidgets import QApplication, QMainWindow, QMenu, QVBoxLayout, QSizePolicy, QMessageBox, QWidget

from numpy import arange, sin, pi
from matplotlib.backends.backend_qt5agg import FigureCanvasQTAgg as FigureCanvas
from matplotlib.figure import Figure


class MyMplCanvas(FigureCanvas):
    """这是一个窗口部件，即QWidget（当然也是FigureCanvasAgg）"""
    def __init__(self, parent=None, width=5, height=4, dpi=100):
        fig = Figure(figsize=(width, height), dpi=dpi)
        self.axes = fig.add_subplot(111)
        # 每次plot()调用的时候，我们希望原来的坐标轴被清除(所以False)
        # self.axes.hold(False)

        self.compute_initial_figure()

        #
        FigureCanvas.__init__(self, fig)
        self.setParent(parent)

        FigureCanvas.setSizePolicy(self,
                                   QSizePolicy.Expanding,
                                   QSizePolicy.Expanding)
        FigureCanvas.updateGeometry(self)

    def compute_initial_figure(self):
        pass

class MyStaticMplCanvas(MyMplCanvas):
    """静态画布：一条正弦线"""
    def compute_initial_figure(self):
        t = arange(0.0, 3.0, 0.01)
        s = sin(2*pi*t)
        self.axes.plot(t, s)


class MyDynamicMplCanvas(MyMplCanvas):
    """动态画布：每秒自动更新，更换一条折线。"""
    def __init__(self, *args, **kwargs):
        MyMplCanvas.__init__(self, *args, **kwargs)
        timer = QtCore.QTimer(self)
        timer.timeout.connect(self.update_figure)
        timer.start(1000)

    def compute_initial_figure(self):
        self.axes.plot([0, 1, 2, 3], [1, 2, 0, 4], 'r')

    def update_figure(self):
        # 构建4个随机整数，位于闭区间[0, 10]
        l = [random.randint(0, 10) for i in range(4)]

        self.axes.plot([0, 1, 2, 3], l, 'r')
        self.draw()

class ApplicationWindow(QMainWindow):
    def __init__(self):
        QMainWindow.__init__(self)
        self.setAttribute(QtCore.Qt.WA_DeleteOnClose)
        self.setWindowTitle("程序主窗口")

        self.file_menu = QMenu('&File', self)
        self.file_menu.addAction('&Quit', self.fileQuit,
                                 QtCore.Qt.CTRL + QtCore.Qt.Key_Q)
        self.menuBar().addMenu(self.file_menu)

        self.help_menu = QMenu('&Help', self)
        self.menuBar().addSeparator()
        self.menuBar().addMenu(self.help_menu)

        self.help_menu.addAction('&About', self.about)

        self.main_widget = QWidget(self)

        l = QVBoxLayout(self.main_widget)
        sc = MyStaticMplCanvas(self.main_widget, width=5, height=4, dpi=100)
        dc = MyDynamicMplCanvas(self.main_widget, width=5, height=4, dpi=100)
        l.addWidget(sc)
        l.addWidget(dc)

        self.main_widget.setFocus()
        self.setCentralWidget(self.main_widget)
        # 状态条显示2秒
        self.statusBar().showMessage("matplotlib 万岁!", 2000)

    def fileQuit(self):
        self.close()

    def closeEvent(self, ce):
        self.fileQuit()

    def about(self):
        QMessageBox.about(self, "About",
        """embedding_in_qt5.py example
        Copyright 2015 BoxControL

        This program is a simple example of a Qt5 application embedding matplotlib
        canvases. It is base on example from matplolib documentation, and initially was
        developed from Florent Rougon and Darren Dale.

        http://matplotlib.org/examples/user_interfaces/embedding_in_qt4.html

        It may be used and modified with no restriction; raw copies as well as
        modified versions may be distributed without limitation.
        """
        )

if __name__ == '__main__':
    app = QApplication(sys.argv)

    aw = ApplicationWindow()
    aw.setWindowTitle("PyQt5 与 Matplotlib 例子")
    aw.show()
    #sys.exit(qApp.exec_())
    app.exec_()