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我在 https://doc.qt.io/qt-5/qtsql-relationaltablemodel-relationaltablemodel-cpp.html修改了关系表模型

我希望能够将我的更改保存到我的数据库中,但它只保存前两列,而不是主键查找行。另外,我无法删除行。我已经搜索过,但没有找到有关如何执行此操作的任何信息。我究竟做错了什么?

我使用的样本数据是:

CREATE TABLE `category` ( `Id` INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT, `DrinkType` TEXT NOT NULL);
INSERT INTO `category` VALUES (1,'Non-alcoholic');
INSERT INTO `category` VALUES (2,'Alcoholic');
CREATE TABLE "drinks" ( `Id` INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT, `Name` TEXT NOT NULL, `Type` INTEGER );
INSERT INTO `drinks` VALUES (1,'Coca Cola',1);
INSERT INTO `drinks` VALUES (2,'Pilsner',2);

我的代码:

def addRecord():
    model.insertRow(model.rowCount())

def delRecord():
    model.removeRow(view.currentIndex().row())
    model.select()

app = QtWidgets.QApplication(sys.argv)

window = QtWidgets.QWidget()
window.setWindowTitle("QRelationalSqlTableModel")

con = QtSql.QSqlDatabase.addDatabase('QSQLITE')
con.setDatabaseName('drinks.db')
con.open()

model = QtSql.QSqlRelationalTableModel(parent = window)
model.setEditStrategy(QtSql.QSqlTableModel.OnManualSubmit)
model. setTable('drinks')
model.setRelation(2, QtSql.QSqlRelation('category', 'id', 'drinktype'))
model.select()

model.setHeaderData(1, QtCore.Qt.Horizontal, 'Name')
model.setHeaderData(3, QtCore.Qt.Horizontal, 'Type of drink')

vbox = QtWidgets.QVBoxLayout()

view = QtWidgets.QTableView()
view.setModel(model)
view.setItemDelegate(QtSql.QSqlRelationalDelegate(view))
view.hideColumn(0)
view.setColumnWidth(1, 150)
view.setColumnWidth(2, 150)

vbox.addWidget(view)
btnAdd = QtWidgets.QPushButton("&Add record")
btnAdd.clicked.connect(addRecord)
vbox.addWidget(btnAdd)
btnDel = QtWidgets.QPushButton("&Delete record")
btnDel.clicked.connect(delRecord)
vbox.addWidget(btnDel)

window.setLayout(vbox)
window.resize(430, 250)
window.show()
sys.exit(app.exec_())
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1 回答 1

1

问题之一是因为您使用了不合适的策略,如果使用OnManualSubmit必须调用该方法submitAll()以便将更改记录在数据库中,如果您不想这样做,最好使用OnRowChange,使用此策略更改将在添加压力值后输入或选择另一行。

如果您想从必须使用的数据库中删除一行deleteRowFromTable(),您正在使用removeRow(),但这只会删除视图中的行,而不是数据库中的行,因此稍后会刷新数据,显示新的行。

def addRecord():
    model.insertRow(model.rowCount())
    view.scrollToBottom()

def delRecord():
    model.deleteRowFromTable(view.currentIndex().row())
    model.select()

app = QtWidgets.QApplication(sys.argv)

window = QtWidgets.QWidget()
window.setWindowTitle("QRelationalSqlTableModel")

con = QtSql.QSqlDatabase.addDatabase('QSQLITE')
con.setDatabaseName('drinks.db')
con.open()

model = QtSql.QSqlRelationalTableModel(parent = window)
model.setEditStrategy(QtSql.QSqlTableModel.OnRowChange)
model. setTable('drinks')
model.setRelation(2, QtSql.QSqlRelation('category', 'id', 'drinktype'))
model.select()

model.setHeaderData(1, QtCore.Qt.Horizontal, 'Name')
model.setHeaderData(3, QtCore.Qt.Horizontal, 'Type of drink')

vbox = QtWidgets.QVBoxLayout()

view = QtWidgets.QTableView()
view.setModel(model)
view.setItemDelegate(QtSql.QSqlRelationalDelegate(view))
view.hideColumn(0)
view.setColumnWidth(1, 150)
view.setColumnWidth(2, 150)

vbox.addWidget(view)
btnAdd = QtWidgets.QPushButton("&Add record")
btnAdd.clicked.connect(addRecord)
vbox.addWidget(btnAdd)
btnDel = QtWidgets.QPushButton("&Delete record")
btnDel.clicked.connect(delRecord)
vbox.addWidget(btnDel)

window.setLayout(vbox)
window.resize(430, 250)
window.show()
sys.exit(app.exec_())
于 2018-07-13T16:56:07.440 回答