Issue creating widget plugin

[Dragoon]

Hallo, I created a custom Qt widget in Qt Creator (C++).
I tought to create a plugin to share this widget as a lib.
I followed the tutorial verbatim but when I try to build the plugin project I got an error in the line commented below:

#include <QGraphicsOpacityEffect>
..
#include <QWidget>
#include <QtUiPlugin/QDesignerExportWidget>

class QDESIGNER_WIDGET_EXPORT QVirtualPad : public QWidget {
Q_OBJECT
private:
explicit QVirtualPad(QWidget *parent = nullptr);
...
QGraphicsOpacityEffect mOpacityEffect = 
QGraphicsOpacityEffect(this); // Deleted costructor error.
...
};

The error complains about a deleted constructor of QGraphicsOpacityEffect class (it doesn't seem to be deleted anyway).
This issue appears only when I try to compile the plugin not when compiling and using the custom widget class inside a form (of course the widget files are the same in both cases).
Why?
Maybe Qt Creator cannot compile Designer plugins?

Best regards,
Mike

[Dragoon]

I fixed it moving the initialization of mOpacityEffect in class constructor initalizer list ... but maybe the problem is different may it depends from CONFIG = C++ project directive?

[Christian Ehrlicher]

@Dragoon said in Issue creating widget plugin:

The error complains about a deleted constructor of QGraphicsOpacityEffect class (it doesn't seem to be deleted anyway).

And the error is correct - QObject's are not copyable. Use a pointer instead.

[Dragoon]

@Christian-Ehrlicher you're correct for sure but why the error is reported only when compiling the plugin and not when compiling the application project?

[Christian Ehrlicher]

@Dragoon said in Issue creating widget plugin:

and not when compiling the application project?

I don't understand correctly but why would you add the designer plugin class into an application?

[Dragoon]

This post is deleted!

[Christian Ehrlicher]

@Dragoon said in Issue creating widget plugin:

s not reported when the same source code is compiled for being used in a Qt widget form

You will get the error there too but you don't compile this piece of code in your application - it's only needed when you create a designer plugin.

[Dragoon]

@Christian-Ehrlicher Nope... the error was a line of code of the widget class that was shared both from plugin and application form .
So it should have repoted in both compliation stages... anyway at this time is fixed.