Pyqt5 简明教程

PyQt5 - Hello World

使用 PyQt 创建简单的 GUI 应用程序涉及以下步骤 −

Creating a simple GUI application using PyQt involves the following steps −

  1. Import QtCore, QtGui and QtWidgets modules from PyQt5 package.

  2. Create an application object of QApplication class.

  3. A QWidget object creates top level window. Add QLabel object in it.

  4. Set the caption of label as "hello world".

  5. Define the size and position of window by setGeometry() method.

  6. Enter the mainloop of application by app.exec_() method.

以下是 PyQt 中执行 Hello World 程序的代码：

Following is the code to execute Hello World program in PyQt −

import sys
from PyQt5.QtCore import *
from PyQt5.QtGui import *
from PyQt5.QtWidgets import *
def window():
   app = QApplication(sys.argv)
   w = QWidget()
   b = QLabel(w)
   b.setText("Hello World!")
   w.setGeometry(100,100,200,50)
   b.move(50,20)
   w.setWindowTitle("PyQt5")
   w.show()
   sys.exit(app.exec_())
if __name__ == '__main__':
   window()

上述代码生成以下输出 -

The above code produces the following output −

hello world

还可以为上述代码开发面向对象的解决方案。

It is also possible to develop an object oriented solution of the above code.

  1. Import QtCore, QtGui and QtWidgets modules from PyQt5 package.

  2. Create an application object of QApplication class.

  3. Declare window class based on QWidget class

  4. Add a QLabel object and set the caption of label as "hello world".

  5. Define the size and position of window by setGeometry() method.

  6. Enter the mainloop of application by app.exec_() method.

以下是面向对象解决方案的完整代码：

Following is the complete code of the object oriented solution −

import sys
from PyQt5.QtCore import *
from PyQt5.QtGui import *
from PyQt5.QtWidgets import *
class window(QWidget):
   def __init__(self, parent = None):
      super(window, self).__init__(parent)
      self.resize(200,50)
      self.setWindowTitle("PyQt5")
      self.label = QLabel(self)
      self.label.setText("Hello World")
      font = QFont()
      font.setFamily("Arial")
      font.setPointSize(16)
      self.label.setFont(font)
      self.label.move(50,20)
def main():
   app = QApplication(sys.argv)
   ex = window()
   ex.show()
   sys.exit(app.exec_())
if __name__ == '__main__':
   main()
hello worlds