【发布时间】：2018-09-18 23:11:36
【问题描述】：
使用 PyQt5，我正在尝试构建一个显示两个部分的 GUI 部分；一个在 QTableView（Overview 类）中给出概述，另一个在 QTabWidget（DetailledView 类）中显示概述的所选项目的详细信息。
现在，QTabWidget 中的数据分布在多个选项卡中，显示来自不同表的数据（它比下面的最小示例复杂得多）。由于这些行为类似于键：值对，因此我想垂直显示它们而不是水平显示它们。所以我有一个 InvertedTable 类可以做到这一点。
但是，QTabWidget 表的过滤并不完全有效：当我在概览表中选择一个项目时，QTabWidget 上的过滤器确实会更新，但只有在我单击不同的选项卡后才能看到。
我认为问题在于代理模型的分层：对于 InvertedTables，我有两层代理模型。一种是普通的 QSortFilterProxyModel，我用它来过滤要显示的正确数据子集。最重要的是，还有另一个代理模型（“FlippedProxyModel”，从 QSortFilterProxyModel 子类化）来反转数据。我使用第一个进行过滤，我认为这就是 QTableViews 没有立即更新的原因。 （当我在下面的代码中使用 SQLTables 而不是 InvertedTables 时，一切都很好 - 当然，除了方向。）
这大概也是过滤后有空列的原因吧……
我可以将翻转模型放在过滤器模型下方，但是我要过滤的列在过滤时已经是行，那么我该如何过滤呢？ （另外，显示的表格可能会变大，所以使用过滤拳头似乎是个好主意。）
如何使用 QSortProxyFilterModels 过滤和垂直反转表格，以便显示它的 QTableView 在过滤后立即更新？
一个 MCVE 包含在下面：
#!/usr/bin/python3
from PyQt5.QtSql import QSqlDatabase, QSqlQuery, QSqlTableModel
from PyQt5.QtWidgets import (QTableView, QTabWidget, QGridLayout, QWidget,
QApplication)
from PyQt5.QtCore import (Qt, pyqtSignal)
from PyQt5.Qt import QModelIndex, QSortFilterProxyModel, QSqlRelationalDelegate
import sys
db_file = "test.db"
#========================================
# handle database:
def create_connection(db_file):
db = QSqlDatabase.addDatabase("QSQLITE")
db.setDatabaseName(db_file)
if not db.open():
print("Cannot establish a database connection to {}!".format(db_file))
return False
return db
def fill_tables():
q = QSqlQuery()
q.exec_("DROP TABLE IF EXISTS Manufacturers;")
q.exec_("CREATE TABLE Manufacturers (Name TEXT, Country TEXT);")
q.exec_("INSERT INTO Manufacturers VALUES ('VW', 'Germany');")
q.exec_("INSERT INTO Manufacturers VALUES ('Honda' , 'Japan');")
q.exec_("DROP TABLE IF EXISTS Cars;")
q.exec_("CREATE TABLE Cars (Company TEXT, Model TEXT, Year INT);")
q.exec_("INSERT INTO Cars VALUES ('Honda', 'Civic', 2009);")
q.exec_("INSERT INTO Cars VALUES ('VW', 'Golf', 2013);")
q.exec_("INSERT INTO Cars VALUES ('VW', 'Polo', 1999);")
#========================================
# general classes:
class FlippedProxyModel(QSortFilterProxyModel):
"""a proxy model where all columns and rows are inverted
(compared to the source model);
source: http://www.howtobuildsoftware.com/index.php/how-do/bgJv/pyqt-pyside-qsqltablemodel-qsqldatabase-qsqlrelationaltablemodel-with-qsqlrelationaldelegate-not-working-behind-qabstractproxymodel
"""
def __init__(self, parent=None):
super().__init__(parent)
def mapFromSource(self, index):
return self.createIndex(index.column(), index.row())
def mapToSource(self, index):
return self.sourceModel().index(index.column(), index.row(), QModelIndex())
def columnCount(self, parent):
return self.sourceModel().rowCount(QModelIndex())
def rowCount(self, parent):
return self.sourceModel().columnCount(QModelIndex())
def index(self, row, column, parent):
return self.createIndex(row, column)
def parent(self, index):
return QModelIndex()
def data(self, index, role):
return self.sourceModel().data(self.mapToSource(index), role)
def headerData(self, section, orientation, role):
if orientation == Qt.Horizontal:
return self.sourceModel().headerData(section, Qt.Vertical, role)
if orientation == Qt.Vertical:
return self.sourceModel().headerData(section, Qt.Horizontal, role)
class FlippedProxyDelegate(QSqlRelationalDelegate):
"""a delegate for handling data displayed through a FlippedProxyModel;
source: http://www.howtobuildsoftware.com/index.php/how-do/bgJv/pyqt-pyside-qsqltablemodel-qsqldatabase-qsqlrelationaltablemodel-with-qsqlrelationaldelegate-not-working-behind-qabstractproxymodel
"""
def createEditor(self, parent, option, index):
proxy = index.model()
base_index = proxy.mapToSource(index)
return super(FlippedProxyDelegate, self).createEditor(parent, option, base_index)
def setEditorData(self, editor, index):
proxy = index.model()
base_index = proxy.mapToSource(index)
return super(FlippedProxyDelegate, self).setEditorData(editor, base_index)
def setModelData(self, editor, model, index):
base_model = model.sourceModel()
base_index = model.mapToSource(index)
return super(FlippedProxyDelegate, self).setModelData(editor, base_model, base_index)
class SQLTable(QWidget):
def __init__(self, query):
super().__init__()
self.create_model(query)
self.init_UI()
def create_model(self, query):
raw_model = QSqlTableModel()
q = QSqlQuery()
q.exec_(query)
self.check_error(q)
raw_model.setQuery(q)
self.model = QSortFilterProxyModel()
self.model.setSourceModel(raw_model)
def init_UI(self):
self.grid = QGridLayout()
self.setLayout(self.grid)
self.table = QTableView()
self.grid.addWidget(self.table, 1,0)
self.table.setModel(self.model)
def check_error(self, q):
lasterr = q.lastError()
if lasterr.isValid():
print(lasterr.text())
self.mydb.close()
exit(1)
class InvertedTable(SQLTable):
"""a Widget that displays content of an SQLite query inverted
(= with rows and columns flipped);
"""
def __init__(self, query = ""):
self.query = query
super().__init__(query)
self.flipped_model = FlippedProxyModel()
self.flipped_model.setSourceModel(self.model)
self.table.setModel(self.flipped_model)
self.table.setItemDelegate(FlippedProxyDelegate(self.table)) # use flipped proxy delegate
h_header = self.table.horizontalHeader()
h_header.hide()
v_header = self.table.verticalHeader()
v_header.setFixedWidth(70)
self.table.resizeColumnsToContents()
#========================================
# application classes:
class MainWidget(QWidget):
def __init__(self, company):
super().__init__()
self.init_UI()
self.filter(company)
self.overview.company_changed.connect(self.details.filter)
def init_UI(self):
self.resize(400,400)
self.grid = QGridLayout()
self.setLayout(self.grid)
self.overview = Overview()
self.grid.addWidget(self.overview, 0, 0)
self.details = DetailedView()
self.grid.addWidget(self.details, 1, 0)
def filter(self, company):
self.details.filter(company)
class Overview(SQLTable):
company_changed = pyqtSignal(str)
def __init__(self):
query = "select * from Manufacturers"
super().__init__(query)
self.table.clicked.connect(self.on_clicked)
def on_clicked(self, index):
company_index = self.model.index(index.row(), 0)
company = self.model.data(company_index)
self.company_changed.emit(company)
class DetailedView(QTabWidget):
def __init__(self):
super().__init__()
self.add_tab1()
self.add_tab2()
def add_tab1(self):
query = "select * from cars"
self.tab1 = InvertedTable(query)
self.addTab(self.tab1, "Cars")
def add_tab2(self):
query = "SELECT company, count(*) as nr_cars from cars group by company"
self.tab2 = InvertedTable(query)
self.addTab(self.tab2, "Numbers")
def filter(self, company):
for mytab in [self.tab1, self.tab2]:
mytab.model.setFilterKeyColumn(0)
mytab.model.setFilterFixedString(company)
#========================================
# execution:
def main():
mydb = create_connection(db_file)
if not mydb:
sys.exit(-1)
fill_tables()
app = QApplication(sys.argv)
ex = MainWidget('VW')
ex.show()
result = app.exec_()
if (mydb.open()):
mydb.close()
sys.exit(result)
if __name__ == '__main__':
main()
【问题讨论】：
标签： python pyqt pyqt5 qsortfilterproxymodel