PyQtGraph - 从图形项生成图片
在本文中,我们将看到如何在 PyQTGaph 中生成图形项的图片。 PyQtGraph 是一个用于Python的图形和用户界面库,它提供了设计和科学应用程序中通常需要的功能。它的主要目标是提供用于显示数据(绘图、视频等)的快速交互式图形。图是由节点和边组成的非线性数据结构。节点有时也称为顶点,边是连接图中任意两个节点的线或弧。图由一组有限的顶点(或节点)和一组连接一对节点的边组成。生成图片是指将图项的节点和边生成为图片。
我们可以在下面给出的命令的帮助下创建一个图形布局小部件和图形项
# creating graphics layout widget
win = pg.GraphicsLayoutWidget()
# creating a graph item
graph_item = pg.GraphItem()
In order to do this we use generatePicturemethod with the graph item object
Syntax : imv.generatePicture()
Argument : It takes no argument
Return : It returns None
下面是实现
Python3
# importing Qt widgets
from PyQt5.QtWidgets import *
# importing system
import sys
# importing numpy as np
import numpy as np
# importing pyqtgraph as pg
import pyqtgraph as pg
from PyQt5.QtGui import *
from PyQt5.QtCore import *
import pyqtgraph.ptime as ptime
# Image View class
class ImageView(pg.ImageView):
# constructor which inherit original
# ImageView
def __init__(self, *args, **kwargs):
pg.ImageView.__init__(self, *args, **kwargs)
class Window(QMainWindow):
def __init__(self):
super().__init__()
# setting title
self.setWindowTitle("PyQtGraph")
# setting geometry
self.setGeometry(100, 100, 600, 500)
# icon
icon = QIcon("skin.png")
# setting icon to the window
self.setWindowIcon(icon)
# calling method
self.UiComponents()
# showing all the widgets
self.show()
# method for components
def UiComponents(self):
# creating a widget object
widget = QWidget()
# creating a label
label = QLabel("Geeksforgeeks Graph Item")
# setting minimum width
label.setMinimumWidth(130)
# making label do word wrap
label.setWordWrap(True)
# setting configuration options
pg.setConfigOptions(antialias=True)
# creating graphics layout widget
win = pg.GraphicsLayoutWidget()
# adding view box to the graphic layout widget
view = win.addViewBox()
# lock the aspect ratio
view.setAspectLocked()
# creating a graph item
graph_item = pg.GraphItem()
# adding graph item to the view box
view.addItem(graph_item)
# Define positions of nodes
pos = np.array([
[0, 0],
[10, 0],
[0, 10],
[10, 10],
[5, 5],
[15, 5]
])
# Define the set of connections in the graph
adj = np.array([
[0, 1],
[1, 3],
[3, 2],
[2, 0],
[1, 5],
[3, 5],
])
# Define the symbol to use for each node (this is optional)
symbols = ['o', 'x', 'o', 'o', 't', '+']
# Define the line style for each connection (this is optional)
lines = np.array([
(255, 0, 0, 255, 1),
(255, 0, 255, 255, 2),
(255, 0, 255, 255, 3),
(255, 255, 0, 255, 2),
(255, 0, 0, 255, 1),
(255, 255, 255, 255, 4),
], dtype=[('red', np.ubyte), ('green', np.ubyte), ('blue', np.ubyte), ('alpha', np.ubyte), ('width', float)])
# Update the graph
graph_item.setData(pos=pos, adj=adj, pen=lines, size=1, symbol=symbols, pxMode=False)
# Creating a grid layout
layout = QGridLayout()
# minimum width value of the label
label.setMinimumWidth(130)
# setting this layout to the widget
widget.setLayout(layout)
# adding label in the layout
layout.addWidget(label, 1, 0)
# plot window goes on right side, spanning 3 rows
layout.addWidget(win, 0, 1, 3, 1)
# setting this widget as central widget of the main widow
self.setCentralWidget(widget)
# generating the picture of graph item
graph_item.generatePicture()
# create pyqt5 app
App = QApplication(sys.argv)
# create the instance of our Window
window = Window()
# start the app
sys.exit(App.exec())
输出 :