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by rubymamis 907 days ago
These performance issues are vastly different from what I experience on Desktop, so I'm curious to test my app on mobile. In my experience, C++ and QML outperforms comparable native apps by 4x.

Regarding no.3, what do you mean by QTextDocument? My block editor is implemented by each delegate being a TextArea (inh: TextEdit), and it's very fast.

One trick I've learned, is to use `reuseItems`[1][2] in ListView. It gives incredible performance boost. You'll need to adjust some things according to the onPooled and onReused signals, but it's a no-brainer for many use cases.

[1] https://doc.qt.io/qt-6/qml-qtquick-listview.html#reuseItems-...

[2] https://doc.qt.io/qt-6/qml-qtquick-tableview.html#reusing-it...
1 comments
_camm 907 days ago
QTextDocument is a class in Qt::Gui that many of the other text classes/components use. I was thinking you may have implemented your own text handling widget/item, but using delegates of text areas makes sense too.

I will try reuseItems again. It's something I tried before briefly but thought it may have been causing some rendering glitches and removed it. Maybe because I didn't implement onResused or onPooled properly. Thanks!

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rubymamis 907 days ago
> I was thinking you may have implemented your own text handling

Yes, but without QTextDocument as I had some problems with it. I had to implement my own undo/redo/copy/paste/etc.

> It's something I tried before briefly but thought it may have been causing some rendering glitches

Yes, I've experienced some (minor) glitches that I've yet to figure out how to fix. For example, the cursor seems to (sometimes) jump when creating new blocks. Sometimes delegates reappear with animation (while I turned them off when onPooled ran). I'm trying to figure out if I'm doing something incorrectly (highly probable) yet I don't get these issues without reuseItems.

Sure, I hope it works out well for you (:

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