click signal fired when I double click, is this normal?

Chris Bare

I am using Qt 5.10.1 on Linux.
I have a QTableView with both the clicked and doubleClicked signals connected to slots.
When I double click, it fires my clicked slot, then my doubleClicked slot, then my clicked slot again.

Is this normal?
If so, how can I tell that the first click is part of the double click so I can treat them differently?

SGaist

Hi and welcome to devnet,

Yes it's normal, the double click is not a "standalone event", it's two consecutive single clicks.

Why are you reacting to both ?

JonB

@Chris-Bare

If so, how can I tell that the first click is part of the double click so I can treat them differently?

In some shape or form, it it your job to wait to see whether a single click event is followed "shortly" by the double click event. For example, upon single click, start a timer: if the double click arrives cancel the timer and do not process the original as a single click; if it does not arrive by the time of timer expiry, then now process the original event as a single click only.

mpergand

Well, let's see how it works ...

void mousePressEvent(QMouseEvent* ev) { qDebug()<<__FUNCTION__;}
void mouseReleaseEvent(QMouseEvent* ev) {qDebug()<<__FUNCTION__;}
void mouseDoubleClickEvent(QMouseEvent* ev) {qDebug()<<__FUNCTION__;}

On double click, we have the following sequence:

mousePressEvent
mouseReleaseEvent
mouseDoubleClickEvent
mouseReleaseEvent

You only need to look at mousePress and doubleClick events.

For a tableView you can use the following signals:

connect(tableView,SIGNAL(doubleClicked(const QModelIndex &)), ...
connect(tableView->selectionModel(),SIGNAL(selectionChanged(const QItemSelection&, const QItemSelection&)), ...

I

JonB

@mpergand
Ah, I took @SGaist 's

Yes it's normal, the double click is not a "standalone event", it's two consecutive single clicks.

to mean that one received single-click events too when double click. Evidently that is not the case from what you write.

@Chris-Bare wrote:

When I double click, it fires my clicked slot, then my doubleClicked slot, then my clicked slot again.

again that implies to me he gets a clicked event.

Yet your:

On double click, we have the following sequence:

mousePressEvent
mouseReleaseEvent
mouseDoubleClickEvent
mouseReleaseEvent

shows no single click events at all, so I'm confused/lost?

J.Hilk

@JonB said in click signal fired when I double click, is this normal?:

Yet your:

On double click, we have the following sequence:

mousePressEvent
mouseReleaseEvent
mouseDoubleClickEvent
mouseReleaseEvent

shows no single click events at all, so I'm confused/lost?

I don't quite follow the posts as well,

but clicked() event is usually a combination out of press event and release event

mousePressEvent -> pressed()
mouseReleaseEvent -> released()
mousePressed and Released inside the area of the Widget or one of its children -> clicked()

so you can have pressed and released events, without triggering clicked.

but prior to a doubleClicke event, you have 6 Signals: pressed, released, clicked, pressed, released, clicked -> doubleclicked

JonB

@J.Hilk said in click signal fired when I double click, is this normal?:

but prior to a doubleClicke event, you have 6 Signals: pressed, released, clicked, pressed, released, clicked -> doubleclicked

That is precisely my understanding too, i.e. that you do get 2 clicked events as well as the doubled clicked. And that in turn is why I advised the OP in my post above as to how to go about ignoring the clicked events in this situation.

However, it is not what @mpergand claims in his "sequence of events for double-click", and I suspect therefore that his analysis is right, in the politest way.

mpergand

Yet your:

On double click, we have the following sequence:

mousePressEvent
mouseReleaseEvent
mouseDoubleClickEvent
mouseReleaseEvent

shows no single click events at all, so I'm confused/lost?

A single click means two different events, press and release.
The common paradigm used here says: no action takes place on mouse down, only on mouse up.

What do you want to do on first click in a row of your tableWiew ?

Usely, clicking on a row just means selecting it.
On second click, you can allow editing the row.
On double clicking, you can open an dialog (for example)
This is standard beheaviour you have ~~with signals and slots~~ with a TableView.

JonB

@mpergand
I think your reply may be aimed at the OP, not me.

All I was saying, like @J-Hilk , is that your description of the events/signals sent during a double click does not mention the two single click events we, and the OP, believe occur. Period.