Update the QCompleter when calling QLineEdit::setText

[Kerndog73]

I'm using a QLineEdit to let the user choose a directory (there's also a button to show a file dialog). I'm initializing a QCompleter like this:

dirBox = new QLineEdit{this};
auto *completer = new QCompleter{dirBox};
auto *model = new QFileSystemModel{completer};
model->setRootPath(QDir::rootPath());
completer->setModel(model);
dirBox->setCompleter(completer);
dirBox->setText(QDir::homePath());

The problem I'm having is that I want to initialize the QLineEdit with QDir::homePath() but have the QFileSystemModel watching QDir::rootPath(). Calling setText doesn't "update the completer". So if the user appends /De to their home directory, the completer doesn't show them /Desktop. The user must delete the contents of the QLineEdit and start again from the root if they want auto completion.

I could simply do this:

model->setRootPath(QDir::homePath());

...but then the model is no longer watching the root. If there are any changes outside of the home directory, the model won't know about them.

It seems like I can't have my cake and eat it too!

---

As an aside, is there a way to make the completer only show directories and not files?

[jsulm]

@Kerndog73 said in Update the QCompleter when calling QLineEdit::setText:

As an aside, is there a way to make the completer only show directories and not files?

https://doc.qt.io/qt-5/qfilesystemmodel.html#setFilter

[Kerndog73]

@jsulm Excellent! Do you have any ideas for the main problem?

[jsulm]

@Kerndog73 said in Update the QCompleter when calling QLineEdit::setText:

Do you have any ideas for the main problem?

No. I would actually expect this to work as home path is under root.

[Kerndog73]

For anyone who's curious, I ended up subclassing QLineEdit and implementing the completion logic myself. The problem discussed in this topic was not the only problem I had with QCompleter. I ended up with a much nicer experience for the user afterwards. It might not be as efficient (I'm using QDir::entryList) but it's not slow enough for the user to notice.