python3+PyQt5实现柱状图

yipeiwu_com6年前Python基础

本文通过Python3+pyqt5实现了python Qt GUI 快速编程的16章的excise例子。

#!/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_()

运行结果:

以上就是本文的全部内容,希望对大家的学习有所帮助,也希望大家多多支持【听图阁-专注于Python设计】。

相关文章

python 将json数据提取转化为txt的方法

如下所示: #-*- coding: UTF-8 -*- import json import pymysql import os import sys # 数据类型 # { #...

Python 删除连续出现的指定字符的实例

源起 我本想删写一小段代码用于删除一串字符串中的连续重复的指定字符,可能也是长时间不写代码,而且有的时候写代码只途快,很多基础知识都忘光了。我用Python写时一切都没有问题,就差一点,...

PyTorch中permute的用法详解

permute(dims) 将tensor的维度换位。 参数:参数是一系列的整数,代表原来张量的维度。比如三维就有0,1,2这些dimension。 例: import tor...

Python类的动态修改的实例方法

Python类的动态修改的实例方法 相信很多朋友在编程的时候都会想修改一下已经写好的程序行为代码,而最常见的方式就是通过子类来重写父类的一些不满足需求的方法。比如说下面这个例子。 c...

Python 使用with上下文实现计时功能

引言 with 语句是从 Python 2.5 开始引入的一种与异常处理相关的功能(2.5 版本中要通过 from __future__ import with_statement 导...