当对象外部更改时更新 QListView
当模型对象在外部发生更改时，我有一个关于更新 QTreeView （或 QAbstractItemView 的任何子类））的简单问题。假设一个列表显示了 QAbstractItemModel 的子类，并且该模型的一个项目在列表窗口之外发生了更改，并且我们希望使用更改来更新列表。实现这样的目标通常的策略是什么？我查看了 QAbstractItemModel 的 Qt 文档，并且有一个名为“dataChanged”的信号，当数据从模型的变化来看。但由于这个信号（如所有 QAbstractItemModel 函数/信号/槽）与 QModelIndex 一起使用，它并不像文档明确说明的那样持久，我是否应该以某种方式存储我的数据到 >QPersistenModelIndex(es)，所以当我的数据更改时，我将能够找到相应的 QPersistenModelIndex 并将其用作各种 QAbstractItemModel 函数的参数？这就是QPersistentModelIndex(es) 的用途吗？或者我错过了什么？
谢谢。
ps：我想我可以重新加载QTreeView，但是我不知道哪些项目被扩展或哪些被选择。有没有一种策略可以克服这个问题并重新加载列表？
I've a simple question regarding the update of a QTreeView (or any subclass of QAbstractItemView) when a model object changes externally. Let's say that a list shows a subclass of QAbstractItemModel, and an item of that model gets changed outside of the list window, and we would like to update the list with the change. What is the usual strategy to achieve something like this ? I've looked at the Qt documentation of QAbstractItemModel and there is a signal named 'dataChanged' that is (or should be) emited when data from the model changes. But since this signal (as all QAbstractItemModel functions/signals/slots) work with a QModelIndex, which is not persistent as the documentation clearly says, am i supposed to store somehow a mapping of my data to QPersistentModelIndex(es), so when my data change i will be able to find the corresponding QPersistenModelIndex and use that as argument to the various QAbstractItemModel functions ? Is that what QPersistentModelIndex(es) are used for ? Or am i missing something ?
Thank you.
ps: I guess i could just reload the QTreeView, but then i wouldn't know which items were expanded or which were selected. Is there an strategy to overcome this problem and just reload the list ?
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QTreeView已经处理了底层模型数据更改的情况（即模型已发出dataChanged()信号）。这意味着您不需要在视图上做任何额外的工作。如果您要实现自己的模型（
QAbstractItemView的派生类），并且要更改模型的内容，则只需发出dataChanged()< /code> 当您的更改完成时发出信号。信号/槽机制将自动使用该信号通知视图。QTreeViewalready handles the case in which the underlying model's data changed (i.e. the model has emitted thedataChanged()signal). That means you don't need to do any additional work on the view.If you're implementing your own model (a derived class of
QAbstractItemView), and you're making a change to the contents of the model, you simply need to emit thedataChanged()signal when your change is complete. The signal/slot mechanism will automatically inform the view using that signal.