QLabel and right click

[Perdrix]

I have a QLabel called backgroundCalibration whose text I have set to "<a>Some text</a>"

I did:

ui->backgroundCalibration->setVisible(true);
ui->backgroundCalibration->setTextInteractionFlags(Qt::LinksAccessibleByMouse);
ui->backgroundCalibration->setForegroundRole(QPalette::Link);

void	StackingParameters::on_backgroundCalibration_linkActivated(const QString & str)
{
	str;
	//
	// Show the popup menu 
	//
	backgroundCalibrationMenu->exec(QCursor::pos());
}

When I display the Widget containing this label the text is displayed as "Some Text" and is displayed in Blue as I expected.

However when I right-click left-click the text nothing happens! What crucial step did I miss?

TIA
David

[Bonnie]

@Perdrix
You cannot use "<a>Some text</a>" to expect a linkActivated signal.
You must set some text as the link: "<a href="any text">Some text</a>", or the text won't even look like linked.

[jsulm]

@Perdrix said in QLabel and right click:

However when I right-click the text nothing happens!

What do you expect to happen?

[Perdrix]

I expect the slot on_backgroundCalibration_linkActivated() to be driven.

David

[jsulm]

@Perdrix Shouldn't it happen on left mouse button click?

[Perdrix]

Sorry I meant when I LEFT click, nothing happens

David (I'll edit the original text to correct that)

[jsulm]

@Perdrix It seems like you're relying on the auto-connect feature, right? I mean you do not connect the signal to slot explicitly. You could try to connect by yourself to see whether it makes a difference.

[Perdrix]

Yes, I'm using auto-connect and I don't get any warnings about Qt being unable to connect the signals to the slots (as I did when I originally tried to use on_backgroundCalibration_clicked() - that definitely got a complaint.

[JonB]

@Perdrix
Please at least put a qDebug()/breakpoint inside your slot to verify being called, just in case it is being called and you (somehow) can't see the menu!

[jsulm]

@Perdrix The auto-connect feature is not that reliable. I would try with explicit connect. If it complains then post your connect call here and the error.

[Perdrix]

I added:

connect(ui->backgroundCalibration, SIGNAL(linkActivated(const Qstring &)), this, SLOT(on_backgroundCalibration_linkActivated()));

to the ctor code just after the ui->SetupUI() call.

I have a breakpoint inside the slot code at the line that is intended to raise the menu, but it is never reached.

David

[JonB]

@Perdrix
If that is a paste of your code, Qstring is mis-spelt. You would get help if that is not connecting the slot if you changed to new-style signal-slot syntax, which would benefit you in the long run.

[Bonnie]

@Perdrix
You cannot use "<a>Some text</a>" to expect a linkActivated signal.
You must set some text as the link: "<a href="any text">Some text</a>", or the text won't even look like linked.

[JonB]

@Bonnie
Good spot, as usual @Bonnie! Might be nice if the Qt docs reminded us of this somewhere, I didn't see much on what you had to do to a QLabel to make it a clickable link.

[Perdrix]

Yes I spotted that just after I posted and fixed it.

So the code now reads:

connect(ui->backgroundCalibration, SIGNAL(linkActivated(const QString &)), this, SLOT(on_backgroundCalibration_linkActivated(const QString &)));

and received no nastygrams about non-existent signals. Sadly the breakpoint is still not reached.

PS what's the new format for connecting the signals and slots? My book is strictly old school Qt4

David

[jsulm]

@Perdrix Did you read what @Bonnie wrote?
https://wiki.qt.io/New_Signal_Slot_Syntax/de

[Perdrix]

@Bonnie Silly question - why can't I just use <a>Text</a>? It is after all a valid minimal HTML anchor?

I shall change the code immediately to use the format you suggested.

D.

[JonB]

@Perdrix
Because <a>Text</a> is not clickable in HTML, it just defines an anchor point user can jump to (via # on URL), see e.g. https://stackoverflow.com/questions/10510191/valid-to-use-a-anchor-tag-without-href-attribute.

[Perdrix]

@Bonnie said in QLabel and right click:

href="any text"

Thanks Bonnie - that solved it ...