1 import sys, sqlite3
 2 #from PyQt5.QtWidgets import (QWidget, QPushButton, QLabel, QLineEdit, QInputDialog, QApplication, QGridLayout)
 3 from PyQt5.QtWidgets import *
 4 from PyQt5 import QtSql
 5 from PyQt5.QtSql import *
 6 #from PyQt5.QtSql import QSqlDatabase, QSqlQuery
 7 
 8 class Example(QWidget):
 9     def __init__(self):
10         super().__init__()
11         self.initUI()
12 
13     def initUI(self):
14         self.btn = QPushButton('Start',self)#按钮
15         self.btn.clicked.connect(self.showDialog)
16 
17         self.le = QLineEdit(self)#单行编辑框
18 
19         text = QLabel('是')
20 
21         self.answer = QLineEdit(self)
22 
23         grid = QGridLayout()
24         grid.setSpacing(10)
25 
26         grid.addWidget(self.btn,1,0,1,3)#后两个参数可以设置行列跨度。这里的行列跨度是一行三列。
27         grid.addWidget(self.le,2,0)
28         grid.addWidget(text,2,1)
29         grid.addWidget(self.answer,2,2)
30 
31         self.setLayout(grid)
32 
33         self.setGeometry(300,300,350,350)
34         self.setWindowTitle('Input dialog')
35         self.show()
36 
37     def showDialog(self):
38         global text
39         text, ok = QInputDialog.getText(self, 'Input Dialog', 'Enter the rubbish:')
40         if ok:
41             self.le.setText(str(text))
42             self.showAnswer()
43 
44     def showAnswer(self):
45         db = QSqlDatabase.addDatabase('QSQLITE')
46         db.setDatabaseName('Rubbish.db')
47         db.open()
48         query = QSqlQuery()
49         query.prepare(f'select Rclassification from Rub_cl where Rname="{text}"')#双引号是关键
50         query.exec()
51         #query.next()
52         #print(query.value(0))
53         if not query.exec():
54             query.lastError()#返回最后一个报错信息
55         else:
56             query.next()
57             '''
58             QSqlQuery返回的数据集，record是停在第一条记录之前的。
59             所以，在获得数据集后，必须执行next()或first()到第一条记录，
60             这时候record才是有效的。
61             '''
62             answertoprint = query.value(0)
63             self.answer.setText(str(answertoprint))
64         
65         
66 
67 if __name__ == '__main__':
68 
69     app = QApplication(sys.argv)
70     ex = Example()
71     sys.exit(app.exec_())

cd blablablablabla
pyinstaller -D(-F) -i icon.ico rubbish_classification.py