Shorter "super" parameters for virtual override methods

[5k3105]

Using QTreeView OnCurrentChanged, to make it work is a little more verbose than my previous code:

view.OnCurrentChanged(view.current_changed)
view.OnDoubleClicked(view.navpane_item_clicked)

func (view *NavigationPane) current_changed(super func(current *qt.QModelIndex, previous *qt.QModelIndex), current *qt.QModelIndex, previous *qt.QModelIndex) {
	
}

func (view *NavigationPane) navpane_item_clicked(index *qt.QModelIndex) {

}

/// old version
func (view *NavigationPane) _current_changed(current *qt.QModelIndex, previous *qt.QModelIndex) {

}

However, OnDoubleClicked is the same as previous code. Is there a way to make it use just the two parameters?

I noticed in the examples its also like this

w.OnPaintEvent(func(super func(ev *qt.QPaintEvent), ev *qt.QPaintEvent) {
	...
})

Basically, is there away to remove the need to specify a func inside a func (super func) ?

[mappu]

PaintEvent is not a signal/slot - actually it's a C++ virtual method override.

In C++, you should usually call the parent function inside your callback.

In therecipe/qt this was exposed as QWidget.PaintEventDefault(), but I think new Qt users didn't know this well.

Because Miqt puts it as a parameter, there can be a linter warning if it is not used. But I agree that it's inconvenient to type.

• One idea is to switch Miqt to the therecipe/qt design
• Another idea is to add a short typedef for this long func type. Maybe that can be a good middle-ground solution

[5k3105]

For CurrentChanged, it just needs I think 2 parameters

void QTreeView::currentChanged(const QModelIndex &current, const QModelIndex &previous)

For PaintEvent, it is a custom type/class

void QWidget::paintEvent(QPaintEvent *event)

Forgive me for not understanding nuances of cpp, qt or even go....

[5k3105]

I'd also like to mention how nice it is having a new qt library for go. It compiles as fast as go and current conversions (moving from therecipe) have been very quick. I had also been using therecepie with GO111MODULE=off and now I can use go modules :) Thanks!

[arnetheduck]

this was exposed as QWidget.PaintEventDefault()

Using Default might not be a good long-term idea since there might be multiple implementations/overrides when considering multiple levels of inheritance, so it probably makes sense to "mimic" the C++ style here (this->QWidget::paintEvent should probably be something like QWidget_PaintEvent alongside the normal PaintEvent function) - this is the case for the qt_metacall family of functions for example and probably can happen with QAbstractItemModel chains.

Putting it as parameter as it's done now also looks like it introduces a tiny bit of overhead for every call because the "this" parameter must be captured in a closure environment for the callback - not sure if this is significant or not, but it happens even if the "super" call ends up not being called.