Python QTableView没有';t将预期的FocusIn/FocusOut事件发送到eventFilter
我有一个QTableWidget,它带有需要大量水平空间的浮动或复杂条目。通过字符串格式以较少的位数显示值效果很好,但显然,在编辑和存储表中的条目时,我会降低精度 我通过使用eventFilter找到了QLineEdit小部件的解决方案:一个Python QTableView没有';t将预期的FocusIn/FocusOut事件发送到eventFilter,python,pyqt,qtablewidget,qtablewidgetitem,qevent,Python,Pyqt,Qtablewidget,Qtablewidgetitem,Qevent,我有一个QTableWidget,它带有需要大量水平空间的浮动或复杂条目。通过字符串格式以较少的位数显示值效果很好,但显然,在编辑和存储表中的条目时,我会降低精度 我通过使用eventFilter找到了QLineEdit小部件的解决方案:一个FocusIn事件将存储的值以全精度复制到QLineEdit文本字段,一个FocusOut事件或一个Return\u键存储更改的值,并用更少的位数覆盖文本字段 对QTableWidgets使用相同的方法会给我带来以下(可能相关的)问题: FocusIn和F
FocusIn
事件将存储的值以全精度复制到QLineEdit文本字段,一个FocusOut
事件或一个Return\u键
存储更改的值,并用更少的位数覆盖文本字段
对QTableWidgets使用相同的方法会给我带来以下(可能相关的)问题:
- FocusIn和FocusOut事件未按预期生成:当我双击一个项目时,我会得到一个FocusOut事件,单击另一个项目会生成一个FocusIn事件
- 我无法复制已编辑的选定项目的内容,我始终获取未编辑的值
- 通过单击来选择项目不会产生事件
# -*- coding: utf-8 -*-
#from PyQt5.QWidgets import ( ...)
from PyQt4.QtGui import (QApplication, QWidget, QTableWidget, QTableWidgetItem,
QLabel, QVBoxLayout)
import PyQt4.QtCore as QtCore
from PyQt4.QtCore import QEvent
from numpy.random import randn
class EventTable (QWidget):
def __init__(self, parent = None):
super(EventTable, self).__init__(parent)
self.myTable = QTableWidget(self)
self.myTable.installEventFilter(self) # route all events to self.eventFilter()
myQVBoxLayout = QVBoxLayout()
myQVBoxLayout.addWidget(self.myTable)
self.setLayout(myQVBoxLayout)
self.rows = 3; self.columns = 4 # table + data dimensions
self.data = randn(self.rows, self.columns) # initial data
self._update_table() # create table
def eventFilter(self, source, event):
if isinstance(source, (QTableWidget, QTableWidgetItem)):
# print(type(source).__name__, event.type()) #too much noise
if event.type() == QEvent.FocusIn: # 8: enter widget
print(type(source).__name__, "focus in")
self.item_edited = False
self._update_table_item() # focus: display data with full precision
return True # event processing stops here
elif event.type() == QEvent.KeyPress:
print(type(source).__name__, "key pressed")
self.item_edited = True # table item has been changed
key = event.key() # key press: 6, key release: 7
if key in {QtCore.Qt.Key_Return, QtCore.Qt.Key_Enter}: # store entry
self._store_item() # store edited data in self.data
return True
elif key == QtCore.Qt.Key_Escape: # revert changes
self.item_edited = False
self._update_table() # update table from self.data
return True
elif event.type() == QEvent.FocusOut: # 9: leave widget
print(type(source).__name__, "focus out")
self._store_item()
self._update_table_item() # no focus: use reduced precision
return True
return super(EventTable, self).eventFilter(source, event)
def _update_table(self):
"""(Re-)Create the table with rounded data from self.data """
self.myTable.setRowCount(self.rows)
self.myTable.setColumnCount(self.columns)
for col in range(self.columns):
for row in range(self.rows):
self.myTable.setItem(row,col,
QTableWidgetItem(str("{:.3g}".format(self.data[row][col]))))
self.myTable.resizeColumnsToContents()
self.myTable.resizeRowsToContents()
def _update_table_item(self, source = None):
""" Re-)Create the current table item with full or reduced precision. """
row = self.myTable.currentRow()
col = self.myTable.currentColumn()
item = self.myTable.item(row, col)
if item: # is something selected?
if not item.isSelected(): # no focus, show self.data[row][col] with red. precision
print("\n_update_item (not selected):", row, col)
item.setText(str("{:.3g}".format(self.data[row][col])))
else: # in focus, show self.data[row][col] with full precision
item.setText(str(self.data[row][col]))
print("\n_update_item (selected):", row, col)
def _store_item(self):
""" Store the content of item in self.data """
if self.item_edited:
row = self.myTable.currentRow()
col = self.myTable.currentColumn()
item_txt = self.myTable.item(row, col).text()
self.data[row][col] = float(str(item_txt))
print("\n_store_entry - current item/data:", item_txt, self.data[row][col])
if __name__ == "__main__":
import sys
app = QApplication(sys.argv)
mainw = EventTable()
app.setActiveWindow(mainw)
mainw.show()
sys.exit(app.exec_())
你这样做完全是错误的。现有的API已经满足了这类用例的需求,因此有几种解决方案比您目前拥有的解决方案简单得多 可能最简单的方法就是使用一个并重新实现它的方法。这将允许您在表中存储完整的值,但格式不同,以便显示。编辑时,将始终显示完整值(作为字符串):
注:用它来解决这个问题很有诱惑力。但是,
QTableWidgetItem
和QStandardItem
都将DisplayRole
和EditRole
视为一个角色,这意味着需要重新实现它们的数据
和设置数据
方法来获得所需的功能。一个真正优雅的解决方案!我想,我得咬一下。。。
from PyQt4.QtGui import (QApplication, QWidget, QTableWidget, QTableWidgetItem,
QLabel, QVBoxLayout,QStyledItemDelegate)
import PyQt4.QtCore as QtCore
from PyQt4.QtCore import QEvent
from numpy.random import randn
class ItemDelegate(QStyledItemDelegate):
def displayText(self, text, locale):
return "{:.3g}".format(float(text))
class EventTable (QWidget):
def __init__(self, parent = None):
super(EventTable, self).__init__(parent)
self.myTable = QTableWidget(self)
self.myTable.setItemDelegate(ItemDelegate(self))
myQVBoxLayout = QVBoxLayout()
myQVBoxLayout.addWidget(self.myTable)
self.setLayout(myQVBoxLayout)
self.rows = 3; self.columns = 4 # table + data dimensions
self.data = randn(self.rows, self.columns) # initial data
self._update_table() # create table
def _update_table(self):
self.myTable.setRowCount(self.rows)
self.myTable.setColumnCount(self.columns)
for col in range(self.columns):
for row in range(self.rows):
item = QTableWidgetItem(str(self.data[row][col]))
self.myTable.setItem(row, col, item)
self.myTable.resizeColumnsToContents()
self.myTable.resizeRowsToContents()
if __name__ == "__main__":
import sys
app = QApplication(sys.argv)
mainw = EventTable()
app.setActiveWindow(mainw)
mainw.show()
sys.exit(app.exec_())