PyQT5之窗口

窗口类型：
QMainWindow：可以包含菜单栏、工具栏、状态栏、标题栏
QWidget：不确定窗口的用途，就使用QWidget
QDialog: 是对话窗口的基类，没有菜单栏、工具栏、状态栏

from PyQt5.QtWidgets import QWidget, QDesktopWidget, QMainWindow, QApplication, QPushButton, QHBoxLayout
from PyQt5 import QtCore, QtGui
from PyQt5.QtGui import QIcon
import sys
import cv2


class FirstMainWin(QMainWindow):
    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        # 设置主窗口的标题
        self.setWindowTitle('第一个主窗口应用，并居中')
        # 设置窗口的尺寸
        self.resize(400, 300)

        self.status = self.statusBar()   # 设置状态栏
        self.status.showMessage("只存在5秒的消息", 5000)

        self.btn1 = QPushButton("退出应用程序")
        # 将信号与槽关联
        self.btn1.clicked.connect(self.on_click_button)

        layout = QHBoxLayout()
        layout.addWidget(self.btn1)

        main_frame = QWidget()
        main_frame.resize(300, 240)
        self.print_size(main_frame)
        main_frame.setLayout(layout)

        self.setCentralWidget(main_frame)

    def print_size(self, main_frame):
        print(main_frame.x(), main_frame.y(), main_frame.width(), main_frame.height())
        print(main_frame.geometry().x(), main_frame.geometry().y(),
              main_frame.geometry().width(), main_frame.geometry().height())
        print(main_frame.frameGeometry().x(), main_frame.frameGeometry().y(),
              main_frame.frameGeometry().width(), main_frame.frameGeometry().height())

    def on_click_button(self):
        sender = self.sender()
        print(sender.text() + "按钮被按下")
        app = QApplication.instance()
        # 对出应用程序
        app.quit()

    def center(self):
        # 获取屏幕坐标系
        screen = QDesktopWidget().screenGemotry()
        # 获取窗口坐标系
        size = self.geometry()
        new_left = (screen.width() - size.width()) / 2
        new_top = (screen.height() - size.height()) / 2
        self.move(new_left, new_top)


if __name__ == '__main__':

    app = QApplication(sys.argv)
    app.setWindowIcon(QIcon('./image/icon/特性.png'))
    main_win = FirstMainWin()
    main_win.show()
    sys.exit(app.exec_())