本篇文章为大家展示了怎么在python3中利用PyQt5实现一个柱状图，内容简明扼要并且容易理解，绝对能使你眼前一亮，通过这篇文章的详细介绍希望你能有所收获。
Python主要应用于：1、Web开发；2、数据科学研究；3、网络爬虫；4、嵌入式应用开发；5、游戏开发；6、桌面应用开发。
#!/usr/bin/env python3
import random
import sys
from 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,QPixmap
class 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_()上述内容就是怎么在python3中利用PyQt5实现一个柱状图，你们学到知识或技能了吗？如果还想学到更多技能或者丰富自己的知识储备，欢迎关注创新互联行业资讯频道。
