Question

I want to enable/disable a checkable item in a QTreeWidget, when a specific signal is sent.

The following code dows not work:

model = QStandardItemModel()
view = QTreeView()
view.setModel(model)
rootItem = QStandardItem()
rootItem = model.invisibleRootItem()

categoryItem = QStandardItem(item)
categoryItem.setCheckable(True)
rootItem.appendRow(categoryItem)

signalSource.availabilityChanged.connect(categoryItem.setEnabled)

It produces the error:

TypeError: unhashable type: 'PySide.QtGui.QStandardItem'

Is there a solution for changing the state or data of a QStandardItem via signal/slot?

Answer 1

This looks like a bug in PySide, as connect should accept any callable (the example code works correctly in PyQt4).

As a workaround, try wrapping QStandardItem methods in a lambda:

signalSource.availabilityChanged.connect(
    lambda enable: categoryItem.setEnabled(enable))

EDIT

To connect the items in a loop, use a default argument, like this:

for button in buttonList:
    item = QStandardItem("Test")
    ...
    button.toggled.connect(
        lambda enable, item=item: item.setEnabled(enable))