python3+PyQt5實現柱狀圖

這篇文章主要為大家詳細介紹了python3+PyQt5實現柱狀圖的方法，具有一定的參考價值，感興趣的小夥伴們可以參考一下

本文通過Python3+pyqt5實現了python Qt GUI 快速編程的16章的excise例子。

#!/usr/bin/env python3import randomimport sysfrom PyQt5.QtCore import (QAbstractListModel, QAbstractTableModel,  QModelIndex, QSize, QTimer, QVariant, Qt,pyqtSignal)from PyQt5.QtWidgets import (QApplication, QDialog, QHBoxLayout,  QListView, QSpinBox, QStyledItemDelegate,QStyleOptionViewItem, QWidget)from PyQt5.QtGui import QColor,QPainter,QPixmapclass BarGraphModel(QAbstractListModel): dataChanged=pyqtSignal(QModelIndex,QModelIndex) def __init__(self):  super(BarGraphModel, self).__init__()  self.__data = []  self.__colors = {}  self.minValue = 0  self.maxValue = 0 def rowCount(self, index=QModelIndex()):  return len(self.__data) def insertRows(self, row, count):  extra = row + count  if extra >= len(self.__data):   self.beginInsertRows(QModelIndex(), row, row + count - 1)   self.__data.extend([0] * (extra - len(self.__data) + 1))   self.endInsertRows()   return True  return False def flags(self, index):  #return (QAbstractTableModel.flags(self, index)|Qt.ItemIsEditable)  return (QAbstractListModel.flags(self, index)|Qt.ItemIsEditable) def setData(self, index, value, role=Qt.DisplayRole):  row = index.row()  if not index.isValid() or 0 > row >= len(self.__data):   return False  changed = False  if role == Qt.DisplayRole:   value = value   self.__data[row] = value   if self.minValue > value:    self.minValue = value   if self.maxValue < value:    self.maxValue = value   changed = True  elif role == Qt.UserRole:   self.__colors[row] = value   #self.emit(SIGNAL("dataChanged(QModelIndex,QModelIndex)"),   #   index, index)   self.dataChanged[QModelIndex,QModelIndex].emit(index, index)   changed = True  if changed:   #self.emit(SIGNAL("dataChanged(QModelIndex,QModelIndex)"),    #   index, index)   self.dataChanged[QModelIndex,QModelIndex].emit(index, index)  return changed def data(self, index, role=Qt.DisplayRole):  row = index.row()  if not index.isValid() or 0 > row >= len(self.__data):   return QVariant()  if role == Qt.DisplayRole:   return self.__data[row]  if role == Qt.UserRole:   return QVariant(self.__colors.get(row,     QColor(Qt.red)))  if role == Qt.DecorationRole:   color = QColor(self.__colors.get(row,     QColor(Qt.red)))   pixmap = QPixmap(20, 20)   pixmap.fill(color)   return QVariant(pixmap)  return QVariant()class BarGraphDelegate(QStyledItemDelegate): def __init__(self, minimum=0, maximum=100, parent=None):  super(BarGraphDelegate, self).__init__(parent)  self.minimum = minimum  self.maximum = maximum def paint(self, painter, option, index):  myoption = QStyleOptionViewItem(option)  myoption.displayAlignment |= (Qt.AlignRight|Qt.AlignVCenter)  QStyledItemDelegate.paint(self, painter, myoption, index) def createEditor(self, parent, option, index):  spinbox = QSpinBox(parent)  spinbox.setRange(self.minimum, self.maximum)  spinbox.setAlignment(Qt.AlignRight|Qt.AlignVCenter)  return spinbox def setEditorData(self, editor, index):  value = index.model().data(index, Qt.DisplayRole)  editor.setValue(value) def setModelData(self, editor, model, index):  editor.interpretText()  model.setData(index, editor.value())class BarGraphView(QWidget): WIDTH = 20 def __init__(self, parent=None):  super(BarGraphView, self).__init__(parent)  self.model = None def setModel(self, model):  self.model = model  #self.connect(self.model,  #  SIGNAL("dataChanged(QModelIndex,QModelIndex)"),  #  self.update)  self.model.dataChanged[QModelIndex,QModelIndex].connect(self.update)  #self.connect(self.model, SIGNAL("modelReset()"), self.update)  self.model.modelReset.connect(self.update) def sizeHint(self):  return self.minimumSizeHint() def minimumSizeHint(self):  if self.model is None:   return QSize(BarGraphView.WIDTH * 10, 100)  return QSize(BarGraphView.WIDTH * self.model.rowCount(), 100) def paintEvent(self, event):  if self.model is None:   return  painter = QPainter(self)  painter.setRenderHint(QPainter.Antialiasing)  span = self.model.maxValue - self.model.minValue  painter.setWindow(0, 0, BarGraphView.WIDTH * self.model.rowCount(),       span)  for row in range(self.model.rowCount()):   x = row * BarGraphView.WIDTH   index = self.model.index(row)   color = QColor(self.model.data(index, Qt.UserRole))   y = self.model.data(index)   painter.fillRect(x, span - y, BarGraphView.WIDTH, y, color)class MainForm(QDialog): def __init__(self, parent=None):  super(MainForm, self).__init__(parent)  self.model = BarGraphModel()  self.barGraphView = BarGraphView()  self.barGraphView.setModel(self.model)  self.listView = QListView()  self.listView.setModel(self.model)  self.listView.setItemDelegate(BarGraphDelegate(0, 1000, self))  self.listView.setMaximumWidth(100)  self.listView.setEditTriggers(QListView.DoubleClicked|          QListView.EditKeyPressed)  layout = QHBoxLayout()  layout.addWidget(self.listView)  layout.addWidget(self.barGraphView, 1)  self.setLayout(layout)  self.setWindowTitle("Bar Grapher")  QTimer.singleShot(0, self.initialLoad) def initialLoad(self):  # Generate fake data  count = 20  self.model.insertRows(0, count - 1)  for row in range(count):   value = random.randint(1, 150)   color = QColor(random.randint(0, 255), random.randint(0, 255),       random.randint(0, 255))   index = self.model.index(row)   self.model.setData(index, value)   self.model.setData(index, QVariant(color), Qt.UserRole)app = QApplication(sys.argv)form = MainForm()form.resize(600, 400)form.show()app.exec_()

運行結果：