[MU4 Issue] MacOS Crash on Plugin with TextField Component

[TrebledJ]

Issue type

Crash or freeze

Bug description

Greetings! When opening a plugin containing a TextField component, the MS app crashes. Replacing the TextField component with TextInput or simply removing it, seems to fix the issue.

Steps to reproduce

1. Open MS.
2. Enable Tuning/Modal Tuning/Modal Temperaments.
3. Open a score.
4. Open any of the above plugins.
5. Witness the amazing crash!

You can also use this plugin to test:

import QtQuick 2.0
import MuseScore 3.0
import QtQuick.Controls 1.0

MuseScore {
    id: plugin
    description: "This is a description."
    version: "4.0.0"
    
    title: qsTr("Test")

    pluginType: "dialog"
    requiresScore: false

    width: 100
    height: 100

    TextField {
        text: "Hi"
    }
}

Screenshots/Screen recordings

No response

MuseScore Version

4.1.1

Regression

Yes, this used to work in MuseScore 3.x and now is broken

Operating system

macOS 12.6.8

Additional context

I have reason to suspect this issue also occurs with macOS 13 Ventura. Also MS 4.1.1.

---

Logs for Modal-Temperaments plugin with TextField.

15:17:17.359 | INFO  | main_thread | ActionsDispatcher | dispatch: try call action: Temperaments
[1142:19200:20230908,151717.689109:ERROR directory_reader_posix.cc:42] opendir /Users/redacted/Library/Application Support/MuseScore/MuseScore4/logs/dumps/attachments/97161e87-d102-4f0e-b18f-fdd867ac15a0: No such file or directory (2)
[1142:19197:20230908,151717.689109:WARNING crash_report_exception_handler.cc:254] UniversalExceptionRaise: (os/kern) failure (5)
zsh: segmentation fault  /Applications/MuseScore\ 4.app/Contents/MacOS/mscore

Sometimes the order of the middle two lines are reversed:

15:17:17.359 | INFO  | main_thread | ActionsDispatcher | dispatch: try call action: Temperaments
[1421:25941:20230908,152932.797494:WARNING crash_report_exception_handler.cc:254] UniversalExceptionRaise: (os/kern) failure (5)
[1421:25942:20230908,152932.798054:ERROR directory_reader_posix.cc:42] opendir /Users/redacted/Library/Application Support/MuseScore/MuseScore4/logs/dumps/attachments/653c9cf5-6a23-43f2-9c7d-b7838f828ec3: No such file or directory (2)
zsh: segmentation fault  /Applications/MuseScore\ 4.app/Contents/MacOS/mscore

Similar messages even with the debug flag enabled (-d).

On checking the /Users/redacted/Library/Application Support/MuseScore/MuseScore4/logs/dumps/attachments/ folder, no files could be found.

[zacjansheski]

The plug-ins do not crash in 4.0, crash first appeared in 4.1

[Jojo-Schmitz]

Seems the bug doesn't reproduce on Windows 11

[cbjeukendrup]

The crash seems to happen deep inside Qt.

As a workaround (or better solution anyway), you can use TextEdit from QtQuick.Controls 2.15.

A possible cause of the crash might be the switch to Qt 5.15.9. That has happened only on macOS, and indeed between 4.0.2 and 4.1.0.

Since QtQuick.Controls 1.0 is deprecated by Qt anyway, I don't know if this should be a top priority.

[TrebledJ]

One issue with QtQuick.Controls 2.15 is the UI. With Controls 1.0, the MuseScore look-and-feel is inherited. But with 2.0+, it reverts to the native style, at least on macOS. I believe this is why many plugins still use QtQuick Controls 1.0: the code is simple and the UI looks good by default, thanks to MS controls.

If there was a way to keep the MuseScore style (either by importing a MuseScore controls folder or using delegates), then I'm all for switching to Controls 2.0+. But currently documentation about this (within MS) is lacking.

[cbjeukendrup]

You can import MuseScore's own controls using import MuseScore.UiComponents 1.0 (and for some things you also need import MuseScore.Ui 1.0).
This gives access to the real components used in MuseScore's own UI. The components from QtQuick.Controls 1.0 are actually emulating QWidgets, and MuseScore 4 contains some special styling code to make QWidgets look a bit like MuseScore's QML style.
However, note that most of MuseScore's own components are custom, and have not exactly the same API and behaviour as those from Qt. So, the Qt documentation is not going to be helpful for them. There is no real documentation either; the best thing you can do is just look how these components are used in MuseScore itself. That might be a difficulty.

[TrebledJ]

Ah cool, thanks for the pointers. I'll play around with MuseScore's QML components then.

[Jojo-Schmitz]

Is QtQuick.Controls 2.2 save too? 2.15 is not available for Mu3 (Qt 5.9), so that'd otherwise break the dual compatibility plugins

[cbjeukendrup]

Yes, the differences between different 2.x versions should not be too big