Text Widgets

There are two basic widgets available for rendering simple text: GtkLabel is for displaying non-editable text and GtkEntry is for editable text.

GtkLabel

A GtkLabel is the most basic text widget and has already been used behind the scenes in any previous example involving a GtkButton. A GtkLabel is constructed by calling

label = GtkLabel("My text")

The text of a label can be changed using the label property or Gtk4.text

Gtk4.text(label,"My other text")
label.label = "My final text"

Furthermore, a label has limited support for adding formatted text. This is done using the Gtk4.markup function:

Gtk4.markup(label,"""<b>My bold text</b>\n
                          <a href=\"https://www.gtk.org\"
                          title=\"Our website\">GTK+ website</a>""")

The syntax for this markup text is borrowed from HTML and explained here.

A label can be made selectable (so that it can be copied and pasted elsewhere) using

Gtk4.selectable(label,true)

The justification of a label can be changed in the following way:

Gtk4.justify(label,Gtk4.Justification_RIGHT)

Possible values of the enum Justification are LEFT,RIGHT,CENTER, and FILL.

Automatic line wrapping can be enabled using

Gtk4.text(label,repeat("Very long text! ",20))
Gtk4.wrap(label,true)

Note that wrapping will only occur if the size of the widget is limited by layout constraints.

GtkEntry

The entry widget allows the user to enter text. The entered text can be read and written using

ent = GtkEntry()
ent.text = "My String"
str = ent.text

A maximum number of characters can be set using ent.max_length = 10.

Sometimes you might want to make the widget non-editable. This can be done using the call

# using the accessor method
Gtk4.editable(GtkEditable(ent),false)
# using the property system
ent.editable = false

If you want to use the entry to retrieve passwords you can hide the visibility of the entered text. This can be achieved by calling

ent.visibility = false

To get notified by changes to the entry one can listen to the "changed" event.

GtkSearchEntry

A special variant of the entry that can be used as a search box is GtkSearchEntry. It is equipped with a button to clear the entry.