我正在PYQT5中创建一个GUI，该GUI应该从多个相关的SQLite表中提供多个视图。我已经实现了这些视图将通过qstackedwidget显示。
现在，其中一些视图用于概述目的，而另一些视图则是在概述中显示的数据子集上进行更多删除的视图。我想通过RightClick从概述中访问概述。
我提供了一个最小的例子，其中有以下汽车。(抱歉，这有点长，但是需要提供一个完整的工作示例。我尽可能地减少了它。(目标是向概述中选择的公司的汽车展示Detaillview。p>这已经提供了从RightClick上的DETAILLVIEW概述的访问权限，但是公司的信息未传递。因此，即使从"大众"访问detaillview时，self.mycompany也会更新，但car_widget却没有，因此detaillview显示了有关"本田"汽车的信息(默认值(。
。有没有办法与合适的公司更新CAR_WIDGIT？还是我需要在运行时创建detaillview？(这甚至有效吗？
如何根据另一个视图中选择的内容在qstackedwidget中更新一个视图的qtableModel？
这是代码：
#!/usr/bin/python3
from PyQt5 import QtSql
from PyQt5.QtWidgets import (QMainWindow, QWidget, QApplication, QGridLayout,
QStackedWidget, QTableView, QMenu)
from PyQt5.QtCore import Qt, QModelIndex
import sys
class MainGUI(QMainWindow):
def __init__(self):
super().__init__()
self.mycompany = "Honda"
self.create_connection()
self.fill_tables()
self.init_UI()
def create_connection(self):
self.db = QtSql.QSqlDatabase.addDatabase("QSQLITE")
self.db.setDatabaseName("test.db")
if not self.db.open():
print("Cannot establish a database connection to {}!".format(self.db_file))
return False
def fill_tables(self):
self.db.transaction()
q = QtSql.QSqlQuery()
q.exec_("DROP TABLE IF EXISTS Manufacturers;")
q.exec_("CREATE TABLE Manufacturers (CompanyId INT PRIMARY KEY, Name TEXT, Country TEXT);")
q.exec_("INSERT INTO Manufacturers VALUES (1, 'VW', 'Germany');")
q.exec_("INSERT INTO Manufacturers VALUES (2, 'Honda' , 'Japan');")
q.exec_("DROP TABLE IF EXISTS Cars;")
q.exec_("CREATE TABLE Cars (Model TEXT, Year INT, Company INT);")
q.exec_("INSERT INTO Cars VALUES ('Civic', 2009, 'Honda');")
q.exec_("INSERT INTO Cars VALUES ('Golf', 2013, 'VW');")
q.exec_("INSERT INTO Cars VALUES ('Polo', 1999, 'VW');")
self.db.commit()
def init_UI(self):
self.central_widget = QWidget()
self.setCentralWidget(self.central_widget)
self.grid = QGridLayout()
self.central_widget.setLayout(self.grid)
self.setLayout(self.grid)
self.make_stack()
self.show()
def make_stack(self):
self.Stack = QStackedWidget(self)
company_view = QWidget()
layout = QGridLayout()
company_view.setLayout(layout)
self.company_widget = Overview()
layout.addWidget(self.company_widget, 0, 0)
self.company_widget.table.customContextMenuRequested.connect(self.open_menu)
self.Stack.addWidget(company_view)
car_view = QWidget()
layout2 = QGridLayout()
car_view.setLayout(layout2)
car_widget = DetailedView(self.mycompany)
layout2.addWidget(car_widget, 0, 0)
self.Stack.addWidget(car_view)
self.grid.addWidget(self.Stack, 0,1)
def open_menu(self, pos):
menu = QMenu()
show_act = menu.addAction("Show cars")
action = menu.exec_(self.company_widget.table.mapToGlobal(pos))
if action == show_act:
row = self.company_widget.table.indexAt(pos).row()
myindex = self.company_widget.model.index(row, 1, QModelIndex())
company = self.company_widget.model.data(myindex)
self.mycompany = company
self.Stack.setCurrentIndex(1)
class MyTable(QWidget):
def __init__(self):
super().__init__()
self.create_connection()
self.create_model()
self.init_UI()
def create_connection(self):
self.db = QtSql.QSqlDatabase.addDatabase("QSQLITE")
self.db.setDatabaseName("test.db")
if not self.db.open():
print("Cannot establish a database connection to {}!".format(self.db_file))
return False
def create_model(self):
self.model = None
def init_UI(self):
self.grid = QGridLayout()
self.setLayout(self.grid)
self.table = QTableView()
self.table.setModel(self.model)
self.table.setContextMenuPolicy(Qt.CustomContextMenu)
self.grid.addWidget(self.table, 0, 0)
def closeEvent(self, e):
if (self.db.open()):
self.db.close()
def check_error(self, q):
lasterr = q.lastError()
if lasterr.isValid():
print(lasterr.text())
self.db.close()
exit(1)
class Overview(MyTable):
def __init__(self):
super().__init__()
def create_model(self):
self.model = QtSql.QSqlTableModel()
q = QtSql.QSqlQuery()
query = "SELECT * from Manufacturers"
q.exec_(query)
self.model.setQuery(q)
class DetailedView(MyTable):
def __init__(self, company):
self.company = company
super().__init__()
def create_model(self):
self.model = QtSql.QSqlTableModel()
q = QtSql.QSqlQuery()
query = "SELECT * from cars where company = '{}'".format(self.company)
q.exec_(query)
self.model.setQuery(q)
def main():
app = QApplication(sys.argv)
ex = MainGUI()
ex.show()
result = app.exec_()
sys.exit(result)
if __name__ == '__main__':
main()
继承的目标之一是，班级实现了孩子可以做的常见任务，在您的情况下，您不观察到这些任务，例如创建模型必须在父亲中完成，因为所有的孩子都会做。
另一方面，使用QSQLTableModel的目标不是使用QSqlQuery，而是使用setTable()，select()和setFilter()等更友好的请求，但这只是浪费，因为您可以使用QSqlQueryModel。
另一方面，我认为您正在假设MainGui的self.mycompany与DetailedView的self.company相同，而您正在创建deletionView对象时所经历的内容，事实是它们不是相同的，在创建对象时，仅复制了该时刻的值，因此，如果更改MainGui的self.company，它将不会更改DetailView的self.company。
重组项目您将获得以下内容：
#!/usr/bin/python3
from PyQt5.QtSql import QSqlDatabase, QSqlQuery, QSqlTableModel
from PyQt5.QtWidgets import (QMainWindow, QWidget, QApplication, QVBoxLayout,
QStackedWidget, QTableView, QMenu)
from PyQt5.QtCore import Qt, QModelIndex, pyqtSignal
import sys
DB_PATH = "test.db"
def create_connection():
db = QSqlDatabase.addDatabase("QSQLITE")
db.setDatabaseName(DB_PATH)
if not db.open():
print("Cannot establish a database connection to {}!".format(DB_PATH))
return False
return True
def fill_tables():
q = QSqlQuery()
q.exec_("DROP TABLE IF EXISTS Manufacturers;")
q.exec_("CREATE TABLE Manufacturers (CompanyId INT PRIMARY KEY, Name TEXT, Country TEXT);")
q.exec_("INSERT INTO Manufacturers VALUES (1, 'VW', 'Germany');")
q.exec_("INSERT INTO Manufacturers VALUES (2, 'Honda' , 'Japan');")
q.exec_("DROP TABLE IF EXISTS Cars;")
q.exec_("CREATE TABLE Cars (Model TEXT, Year INT, Company INT);")
q.exec_("INSERT INTO Cars VALUES ('Civic', 2009, 'Honda');")
q.exec_("INSERT INTO Cars VALUES ('Golf', 2013, 'VW');")
q.exec_("INSERT INTO Cars VALUES ('Polo', 1999, 'VW');")
class MainGUI(QMainWindow):
def __init__(self):
super().__init__()
self.init_UI()
def init_UI(self):
self.central_widget = QWidget()
self.setCentralWidget(self.central_widget)
self.lay = QVBoxLayout(self.central_widget)
self.make_stack()
def make_stack(self):
self.stack = QStackedWidget()
self.lay.addWidget(self.stack)
self.company_widget = Overview()
self.car_widget = DetailedView()
self.stack.addWidget(self.company_widget)
self.stack.addWidget(self.car_widget)
self.company_widget.changedCompany.connect(self.changedCompany)
self.car_widget.backSignal.connect(lambda: self.stack.setCurrentIndex(0))
def changedCompany(self, company):
self.car_widget.filter(company)
self.stack.setCurrentIndex(1)
class SQLTable(QTableView):
def __init__(self, table):
super().__init__()
self.init_UI()
self.create_model(table)
def create_model(self, table):
self.model.setTable(table)
self.model.select()
def init_UI(self):
self.model = QSqlTableModel()
self.setModel(self.model)
self.setContextMenuPolicy(Qt.CustomContextMenu)
class Overview(SQLTable):
changedCompany = pyqtSignal(str)
def __init__(self):
SQLTable.__init__(self, "Manufacturers")
self.customContextMenuRequested.connect(self.open_menu)
def open_menu(self, pos):
menu = QMenu()
show_act = menu.addAction("Show cars")
action = menu.exec_(self.mapToGlobal(pos))
if action == show_act:
row = self.indexAt(pos).row()
ix = myindex = self.model.index(row, 1)
company = self.model.data(ix)
self.changedCompany.emit(company)
class DetailedView(SQLTable):
backSignal = pyqtSignal()
def __init__(self):
SQLTable.__init__(self, "cars")
self.customContextMenuRequested.connect(self.open_menu)
def open_menu(self, pos):
menu = QMenu()
back_act = menu.addAction("Show Manufacturers")
action = menu.exec_(self.mapToGlobal(pos))
if action == back_act:
self.backSignal.emit()
def filter(self, company):
self.model.setFilter("company='{}'".format(company))
def main():
app = QApplication(sys.argv)
if not create_connection():
sys.exit(-1)
fill_tables()
ex = MainGUI()
ex.show()
result = app.exec_()
sys.exit(result)
if __name__ == '__main__':
main()