PyQtDay04--对象的父子关系+信号的操作
作者：互联网
1.对象的父子关系
（1）API及内存管理机制
实际操作：
1 from PyQt5.Qt import *
2
3 class Window(QWidget):
4 def __init__(self):
5 super().__init__()
6 self.setWindowTitle("QObject的学习")
7 self.resize(500, 500)
8 self.setup_ui()
9
10 def setup_ui(self):
11 #self.QObject_ceshi()
12 self.QObject_对象的父子关系操作()
13
14 def QObject_对象的父子关系操作(self):
15 # **********测试API************开始
16 # obj1=QObject()
17 # obj2=QObject()
18 # obj3=QObject()
19 #
20 # print('obj1',obj1) # 0x0000028ED85CF1F8
21 # print('obj2', obj2) # 0x0000028ED85CF0D8
22 # print('obj3',obj3) # 0x0000013E9DE6F168
23 #
24 # obj1.setParent(obj2)
25 # obj3.setParent(obj2)
26 # print(obj1.parent()) # 0x0000028ED85CF0D8
27 # print(obj2.children()) # 两个
28 # **********测试API************结束
29
30 # ********内存管理机制**********开始
31 obj1=QObject()
32 obj2=QObject()
33
34 obj2.setParent(obj1)
35
36 # 开始监听obj2对象被释放
37 obj2.destroyed.connect(lambda:print('obj2对象被释放了')) # obj2对象被释放了
38
39 # *********内存管理机制*********结束
40
41
42 if __name__ == '__main__':
43 import sys
44
45 app=QApplication(sys.argv)
46 window=Window()
47 window.show()
48 sys.exit(app.exec_())
（2）应用场景
（3）【案例】
1 from PyQt5.Qt import *
2
3 class Window(QWidget):
4 def __init__(self):
5 super().__init__()
6 self.setWindowTitle("QObject的学习")
7 self.resize(500, 500)
8 self.setup_ui()
9
10 def setup_ui(self):
11 #self.QObject_ceshi()
12 self.QObject_对象的父子关系操作()
13
14 def QObject_对象的父子关系操作(self):
15 # **********测试API************开始
16 # obj1=QObject()
17 # obj2=QObject()
18 # obj3=QObject()
19 #
20 # print('obj1',obj1) # 0x0000028ED85CF1F8
21 # print('obj2', obj2) # 0x0000028ED85CF0D8
22 # print('obj3',obj3) # 0x0000013E9DE6F168
23 #
24 # obj1.setParent(obj2)
25 # obj3.setParent(obj2)
26 # print(obj1.parent()) # 0x0000028ED85CF0D8
27 # print(obj2.children()) # 两个
28 # **********测试API************结束
29
30 # ********内存管理机制**********开始
31 obj1=QObject()
32 obj2=QObject()
33
34 obj2.setParent(obj1)
35
36 # 开始监听obj2对象被释放
37 obj2.destroyed.connect(lambda:print('obj2对象被释放了')) # obj2对象被释放了
38
39 # *********内存管理机制*********结束
40
41
42 if __name__ == '__main__':
43 import sys
44
45 app=QApplication(sys.argv)
46 # window=Window()
47 # window.show()
48
49 # win1=QWidget()
50 # win1.setWindowTitle("红色")
51 # win1.setStyleSheet("background-color:red")
52 # win1.show()
53 #
54 # win2=QWidget()
55 # win2.setWindowTitle("绿色")
56 # win2.setStyleSheet("background-color:green")
57 # # win2.setParent(win1)
58 # win2.resize(200,200)
59 # win2.move(220,120)
60 # win2.show()
61
62 win_root=QWidget()
63
64 label1=QLabel()
65 label1.setText('label1')
66 label1.setParent(win_root)
67 label2 = QLabel()
68 label2.move(50,50)
69 label2.setText('label2')
70 label2.setParent(win_root)
71
72 btn=QPushButton(win_root)
73 btn.move(100,100)
74 btn.setText('btn')
75
76 win_root.show()
77
78 for sub_widget in win_root.findChildren(QLabel):
79 print(sub_widget)
80 sub_widget.setStyleSheet("background-color:green")
81
82 sys.exit(app.exec_())
View Code
2、信号的操作
（1）API操作
1 from PyQt5.Qt import *
2
3 class Window(QWidget):
4 def __init__(self):
5 super().__init__()
6 self.setWindowTitle("QObject的学习")
7 self.resize(500, 500)
8 self.setup_ui()
9
10 def setup_ui(self):
11 self.QObject_信号的操作()
12
13 def QObject_信号的操作(self):
14 self.obj=QObject()
15 **********测试API************开始
16 obj=QObject()
17 # obj.destroyed
18 # obj.objNameChanged
19 def destroy_cao():
20 print("对象被释放了")
21 obj.destroyed.connect(destroy_cao)
22
23 def obj_name_cao(name):
24 print("对象名称发生了改变",name)
25 self.obj.objectNameChanged.connect(obj_name_cao)
26 self.obj.setObjectName('XXX')
27 print(self.obj.signalsBlocked(),'1')
28
29 self.obj.blockSignals(True) # 临时中断连接
30 # self.obj.objectNameChanged.disconnect()
31 self.obj.setObjectName('ooo')
32 print(self.obj.signalsBlocked(), '2')
33
34 self.obj.blockSignals(False) # 恢复连接
35 self.obj.setObjectName('hhhh')
36 print(self.obj.signalsBlocked(), '3')
37 **********测试API************结束
38
39 ***********信号与槽按钮****************开始
40 btn=QPushButton(self)
41 btn.setText('点击我')
42
43 def cao():
44 print("点我做啥？")
45
46 btn.clicked.connect(cao)
47
48 ***********信号与槽按钮****************结束
49
50
51 if __name__ == '__main__':
52 import sys
53 window=Window()
54 window.show()
55 sys.exit(app.exec_())
（2）应用场景
（3）案例
1 from PyQt5.Qt import *
2
3 if __name__ == '__main__':
4 import sys
5
6 app=QApplication(sys.argv)
7 window=QWidget()
8 # 连接窗口标题变化的信号 与 槽
9 def cao(title):
10 print('窗口标题变化了',title)
11 # window.windowTitleChanged.disconnect()
12 window.blockSignals(True)
13 window.setWindowTitle('撩课-'+title)
14 window.blockSignals(False)
15 #window.windowTitleChanged.connect(cao)
16
17 window.windowTitleChanged.connect(cao)
18 window.setWindowTitle("Hello Sz")
19 window.setWindowTitle("Hello Sz2")
20
21 window.show()
22 sys.exit(app.exec_())
View Code
时间：2020-03-02 20:55:52
作者：931935931（QQ）
标签：__,obj2,obj,self,QObject,父子关系,信号,print,PyQtDay04 来源： https://www.cnblogs.com/fengxb1213/p/12397967.html