Develop Reference

not displaying old value when editing cell in a QTableWidget

I have a basic QTableWidget, created with this python code:
from silx.gui import qt
app = qt.QApplication([])
qtw = qt.QTableWidget()
qtw.show()
qtw.setColumnCount(8)
qtw.setRowCount(7)
app.exec_()
The from silx.gui import qt line is just a wrapper that finds out the installed qt wrapper (PyQt4, PyQt5 or PySide) and flattens the qt namespace.
The resulting table has a strange behavior when I edit a cell: as expected, the old text is highligted when I double-click the cell, but the unusual behavior is that the old text remains visible and the new text overlaps with the old one while I'm typing it, until I press enter or I click another cell.
I would like the old text to disappear as soon as I start typing the new one. I know it's possible, because I have an example of program that features a qTableWidget with the behavior I would like to have.
But I cannot find where in that program the cell editing behavior is altered. How can I do this?
Example of "spam" and "eggs" overlayed.
[
EDIT: the code sample without the wrapper business
from PyQt5.Qt import QApplication, QTableWidget, qVersion
app =QApplication([])
print(qVersion())
qtw = QTableWidget()
qtw.show()
qtw.setColumnCount(8)
qtw.setRowCount(7)
app.exec_()
With PyQt4, use this import (also remove the print(qVersion()) line):
from PyQt4.QtGui import QApplication, QTableWidget

My method:
class MyDelegate(QItemDelegate):
def setEditorData(self,editor,index):
editor.setAutoFillBackground(True)
editor.setText(index.data().toString())

Generally, edit behavior is controlled via QItemDelegates. Typically, this is done to provide more advanced editing, or to filter input data or perform some side effects (like update a database) when edits are made. But you can also use it to just clear the editor presented to the user when editing.
class MyDelegate(QItemDelegate):
def setEditorData(self, editor, index):
# Normally, this would set the text of the editor to the current
# value of the cell. If you do nothing here, it will be blank.
editor.clear()
qtw = QTableWidget()
delegate = MyDelegate(qtw)
qtw.setItemDelegate(delegate)

In my case, above problem comes when I set background color of QWidgetTable to transparent. When I remove the setting, there is no old data overlays the new one anymore.
Hope it helps.

You could try connecting the signal emited by QTableWidget cellClicked(int row, int column) with a slot created for clearing the entry. http://pyqt.sourceforge.net/Docs/PyQt4/new_style_signals_slots.html#connecting-disconnecting-and-emitting-signals

Python - Can't Build Window With All The Items

I've tryied to build a Tkinter form in some universal method, but I got a problem.
First look at my Method's code..
def BuildWindow(title, args, icon):
Window = Tk()
Window.title(title)
Window.wm_iconbitmap(icon)
for item in args:
item.master = Window
item.pack()
Window.mainloop()
When I'm trying to run this code, I'm getting two differnet Windows: one with the arguments from the list "args", and the other with the title and the icon only..
I want all the parameters to appear in the same Form..
can someone help me to solve it?
Thanks..

Based on the code presented, I must assume that args contains a list of widgets that have already been created. If they've already been created, an instance of Tk must already exist. Since this function is also creating in instance of Tk, that's why you get two windows.
You must create only a single instance of Tk for your entire application.

Updating cell widgets changes in a Qtable without selecting the cell

well I'm using Pyqt4 in Maya2012 to make a reference editor alike ui. I working with a QtableWidget to make the reference list and i have subwidgets in each cell. One of the widgets is a checkbox that unload or reload the reference.
The problem i have is if a click directly in the checkbox without have the cell selected it doesn't do anything
this is my code:
def listConnections(self):
self.pos=self.sender().currentRow()
wid = self.list.ref_l.cellWidget(self.pos, 0).children()
self.text = self.list.list[self.pos]
self.ref()
for wt in wid:
if type(wt)== type(QCheckBox()):
wt.stateChanged.connect(self.changeState)
if type(wt)== type(QComboBox()):
wt.currentIndexChanged.connect(self.changeType)
I'm calling the function with a "itemSlectionChanged" signal because is the only way i knew i could detect the subwidgets.
All the subwidgets are made in the moment i fill the list.
Is there a way to make what i want?
Edit:
This is how i called the function
self.list.ref_l.itemSelectionChanged.connect(self.listConnections)
and this is how i create all the subwidgets in the cells
def fillList(self):
mayaRef = self.findRef()
if len(mayaRef)>0:
for count in range(0,len(mayaRef)):
self.ref_l.insertRow(count)
wid=QWidget()
cLayout=QHBoxLayout()
wid.setLayout(cLayout)
checkWid=QCheckBox()
nameWid=QLabel()
cLayout.addWidget(nameWid)
nameWid2=QLabel()
cLayout.addWidget(nameWid2)
comWid=QComboBox()
cLayout.addWidget(comWid)
self.ref_l.setCellWidget(count,0,wid)
self.ref_l is my QTable Widget, this is in another code that i'm calling with self.list in the original

You should set up all your connections right after you create the check boxes in fillList. Each item is associated with the path of the reference. You can use a QSignalMapper to map each check box to the path, then connect the signal mapper to your changeState slot. The signal mapper then calls that slot with the path you specified.

cursor gone in PyQT

I have a window containing multiple QRowWidgets, which are custom widgets defined by me. These QRowWidgets contain QLineEdits and other standard widgets. To show or hide certain parts of a QRowWidget, I overdefined the focusInEvent() methodes of all the widgets within it. It works perfectly, when I click on the QRowWidget, the hidden elements appear.
The weird thing is that the blinking cursor line hovewer doesn't appear in the QLineEdits within the custom widgets. I can select them both by a mouse click or with Tab, and a glow effect indicates that the QLineEdit is selected in it, I can select a text in it, or start typing at any location wherever I clicked, but the cursor never appears and it's quite annoying.
My 1st thought was that it is a bug on Mac, but I have the same experience on SuSe Linux.
I'm using python 2.7 and PyQt4.
This is in the __init__() of the QRowWidget:
for i in self.findChildren(QWidget):
i.focusInEvent = self.focusInEvent
And then this is the own focusInEvent():
def focusInEvent(self, event):
if self.pself.focusedLine:
self.pself.focusedLine.setStyleSheet("color: #666;")
self.pself.focusedLine.desc.hide()
self.pself.focusedLine.closebutton.hide()
self.setStyleSheet("color: #000;")
self.desc.show()
self.closebutton.show()
self.pself.focusedLine = self

I suspect you do not make a call to the original focusInEvent() when you override it. Your function should look something like:
def focusInEvent(self,...):
QParent.focusInEvent(self,...)
# the rest of your code
where QParent is the nearest base class for your widgets is.
Either that, or make sure you call focusInEvent() on your QLineEdit widgets as part of your function.
Given the comments, it sounds like you are dynamically reassigning the focusInEvent function on the insantiatations in your custom widget. I would either make a derived class for each of the widgets you use that just overrides focusInEvent as above, or include a line like
type(self).focusInEvent(self,..)
in you function.

QWidget not showing after calling show()

In My App, I have a QWidget which is not showing after I call show(), even though isVisible returns true.
This widget is created from an event of the main application window. But when its started on its own, i.e., as the only widget on an app, it shows up normally.
Anyone knows what may cause this behavior?
Other widgets in my app show up normally only this one is giving me troubles. It actually use to work just fine under a previous version of Qt4 (don't remember which).
the code for the widget is here
update: windows seems to appear and is immediately destroyed.

The relevant code is in hidx/GUI/main.py:
#pyqtSignature("")
def on_actionScatterplot_Matrix_activated(self):
...
spm = scatmat.ScatMat(pars, self.currentdbname)
print "==>", spm.pw.isVisible()
spm.pw.hide()
spm.pw.showMaximized()
print spm.pw.size()
print "==>", spm.pw.isVisible()
#pyqtSignature("int")
def on_rowStart_valueChanged(self, p0):
...
In on_actionScatterplot_Matrix_activated, you create an instance of ScatMat, but don't keep a reference to it. So the window will be briefly shown, and then immediately garbage-collected once the function completes.