Custom tab distances for labels

[nyalldawson]

Allows setting a list of custom tab stop distances, instead of just a single distance

Peek.2024-10-29.13-35.mp4

Sponsored by City of Freiburg im Breisgau

[qgis-bot]

@nyalldawson

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[qgis-bot]

@nyalldawson
This pull request has been tagged as requiring documentation.

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[github-actions]

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[uclaros]

Nice!!
What is the expected behavior when text does not fit within a tabstop?
For example something like

        format = QgsTextFormat()
        format.setFont(getTestFont('bold'))
        format.setSize(20)
        format.setSizeUnit(QgsUnitTypes.RenderUnit.RenderPoints)
        format.setTabPositions([QgsTextFormat.Tab(20), QgsTextFormat.Tab(24)])  # if 4mm are enough to fit a single letter
        format.setTabStopDistanceUnit(Qgis.RenderUnit.Millimeters)
        self.assertTrue(self.checkRender(format,
                                         'text_tab_positions_fixed_size',
                                         text=['with\tmany\ttabs', 'a\tb\tc']))

where the second line's b would fit but the first line's many would not fit.

[nyalldawson]

@uclaros

What is the expected behavior when text does not fit within a tabstop?

It just runs over the tab stop, and the next tab character will advance to the next available tab stop past the current position. And if there's no remaining explicit tab stops, then all remaining tab characters are ignored

[uclaros]

Thanks, it makes sense! Maybe worth adding the test?

[nyalldawson]

@uclaros

Thanks, it makes sense! Maybe worth adding the test?

Ok, done

[DelazJ]

Hi,
I watched the screencast, and sorry for the noob question but, what would be the use case of this feature? IIUC it allows to add different tab spacing between words(?) within a label. But when would I want to do that? Any examples? Thanks.

[nyalldawson]

@DelazJ one cool use case is it allows the creation of table-like labels, because you can have multiline text with different "columns" of text lined up nicely.

[qgis-bot]

@nyalldawson
A documentation ticket has been opened at qgis/QGIS-Documentation#9377
It is your responsibility to visit this ticket and add as much detail as possible for the documentation team to correctly document this change.
Thank you!

[agiudiceandrea]

Please have a look at #60003 and #60004 related issue reports.