Fix string truncation

[Rayzeq]

Description

Some users have issues because gtk truncate text when it shouldn't, so I've added a :truncate property on labels, disabled by default. As specified in the property documentation, it has no effect is show-truncated is false, or if limit-width has a value. This behavior allows configurations using the old system (where limit-width was mandatory to have truncation) to continue working without the need to add :truncate true.

Checklist

• [x] All widgets I've added are correctly documented.
• [x] I added my changes to CHANGELOG.md, if appropriate.
• [x] The documentation in the docs/content/main directory has been adjusted to reflect my changes.
• [x] I used cargo fmt to automatically format all code before committing

[AlaisterLeung]

(defwidget title_module []
  (box :width 600
    (label :text "qwertyuiopasdfghjkl" :limit-width 10)
  )
)

This does not truncate text, but

(defwidget title_module []
  (box
    (label :text "qwertyuiopasdfghjkl" :limit-width 10)
  )
)

This does truncate the label to 10 characters

Is the width property supposed to work like this? If I want the box to be 600px wide (for background color) and keep the label 10 characters, is this the correct way?

[Rayzeq]

According to gtk documentation (GtkLabel:max-width-chars is what is used by :limit-width):

The GtkLabel:width-chars and GtkLabel:max-width-chars properties can be used to control the size allocation of elliptical or wrapped labels. For elliptical labels, if either is specified (and less than the actual text size), it is used as the minimum width, and the actual text size is used as the label's natural width.

From this, it seems that GtkLabel:max-width-chars is not a hard limit, so gtk may not truncate the text if there's enough space to display it in full.

I guess you should do it like this if you want a hard limit:

(defwidget title_module []
  (box :width 600
    (box
        (label :text "qwertyuiopasdfghjkl" :limit-width 10)
    )
  )
)

If you don't care about the ellipsis, you can also put :show-truncated false in your label. It won't show the ellipsis, but it will also make :limit-width a hard limit.

[WantToLearnJapanese]

This has broken the text line wrapping. There is no conditon where gtk_widget.set_ellipsize(pango::EllipsizeMode::None); and gtk_widget.set_max_width_chars(limit_width); are called at the same. So, the wrapping text is broken.

Update: I am sorry it was already broken before you committed.

[Rayzeq]

Yeah gtk_widget.set_max_width_chars was never called before, so it hasn't changed anything. I think you also need gtk_widget.set_wrap(true) as it's not enabled by default.