Mnemonics

Label text may be specified with embedded underscore characters that are used to indicate that the following character should be underlined and used as the mnemonic accelerator (if it's the first underlined character). The set_text_with_mnemonic() method is used to parse the label text for a mnemonic characters. Mnemonics automatically activate any activatable widget the label is inside, such as a gtk.Button; if the label is not inside an activatable widget, you have to tell the label about the target using the set_mnemonic_widget() method. Here's a simple example where the label is inside a button:

  # Pressing Alt+H will activate this button
  button = gtk.Button()
  label = gtk.Label("_Hello")
  label.set_use_underline(True)
  button.add(label)

As a convenience you can create a button with a mnemonic label as follows:

  # Pressing Alt+H will activate this button
  button = gtk.Button(label="_Hello", use_underline=True)

To create a mnemonic for a widget alongside the label, such as a gtk.Entry, you have to point the label at the entry with the set_mnemonic_widget() method:

  # Pressing Alt+H will focus the entry
  entry = gtk.Entry()
  label = gtk.Label("_Hello")
  label.set_use_underline(True)
  label.set_mnemonic_widget(entry)

Markup (styled text)

To make it easy to format text in a label (changing colors, fonts, etc.), the label text can be provided in the Pango markup format which is a simple XML markup format. The gtk.Label.set_markup() method sets the label using text in valid markup format (e.g. '<', '>' and '&' characters must be replaced by &lt;, &gt; and &amp; respectively. For example:

  label = gtk.Label()
  label.set_markup("<small>Small text</small>");

The markup passed to the set_markup() method must be valid. For example, the literal <>& characters must be escaped as &lt;, &gt;, and &amp;. If you pass text obtained from the user, file, or a network to the set_markup() method, you'll want to escape it with the Python Library xml.sax.saxutils.escape() function.

Markup strings are just a convenient way to set the pango.AttrList on a label. Using the set_attributes() method may be a simpler way to set attributes in some cases. Be careful though; pango.AttrList tends to cause internationalization problems, unless you're applying attributes to the entire string because specifying the start_index and end_index for a pango.Attribute requires knowledge of the exact string being displayed, so translations will cause problems.

Selectable labels

Labels can be made selectable with the set_selectable() method. Selectable labels allow the user to copy the label contents to the clipboard. Only labels that contain useful-to-copy information such as error messages should be made selectable.

Text layout

A label can contain any number of paragraphs, but will have performance problems if it contains more than a small number. Paragraphs are separated by newlines or other paragraph separators understood by Pango.

Labels can automatically wrap text if you call the set_line_wrap() method.

The set_justify() method sets how the lines in a label align with one another. If you want to set how the label as a whole aligns in its available space, see the gtk.Misc.set_alignment() method.

gtk.Label.set_text

    def set_text(str)

The set_text() method sets the text within the gtk.Label widget. It replaces any text that was there before and will clear any previously set mnemonic accelerators.

gtk.Label.get_text

    def get_text()

The get_text() method fetches the text from a label widget, as displayed on the screen. This does not include any Pango markup or embedded underscore characters indicating mnemonics. (See get_label()).

gtk.Label.set_attributes

    def set_attributes(attrs)

The set_attributes() method applies a pango.AttrList list of attributes to the label text. The attributes set with this function will be ignored if either the "use-underline" or "use-markup" attributes is True.

gtk.Label.get_attributes

    def get_attributes()

The get_attributes() method returns the attribute list that was set on the label using set_attributes(), if any. This function does not reflect attributes that come from the labels markup (see set_markup()).

gtk.Label.set_label

    def set_label(str)

The set_label() method sets the text of the label. The label is parsed for embedded underscores and Pango markup depending on the values of the "use-underline" and "use-markup" properties.

gtk.Label.get_label

    def get_label()

The get_label() method returns the text from a label widget including any Pango markup and embedded underscores indicating mnemonics. (See get_text() that just returns the text).

gtk.Label.set_markup

    def set_markup(str)

The set_markup() method parses str, which is marked up with the Pango text markup language, and sets the label's text and attribute list.

gtk.Label.set_use_markup

    def set_use_markup(setting)

The set_use_markup() method sets the "use-markup" property to the value of setting. If True the text of the label should be parsed as markup.

gtk.Label.get_use_markup

    def get_use_markup()

The get_use_markup() method returns the value of the "use-markup" property. If True the label's text is parsed as markup. See set_use_markup().

gtk.Label.set_use_underline

    def set_use_underline(setting)

The set_use_underline() method sets the "use-underline" property to the value of setting. If setting is True, an underscore in the text indicates the next character should be used for the mnemonic accelerator key.

gtk.Label.get_use_underline

    def get_use_underline()

The get_use_underline() method returns the value of the "use-underline" property. If True an embedded underscore in the label indicates the next character is a mnemonic. See set_use_underline().

gtk.Label.set_markup_with_mnemonic

    def set_markup_with_mnemonic(str)

The set_markup_with_mnemonic() method parses str as markup, setting the label's text and attribute list based on the parse results. If characters in str are preceded by an underscore, they are underlined indicating that they represent a mnemonic accelerator. The mnemonic key can be used to activate another widget, chosen automatically, or explicitly using the set_mnemonic_widget() method.

gtk.Label.get_mnemonic_keyval

    def get_mnemonic_keyval()

The get_mnemonic_keyval() method returns the value of the "mnemonic-keyval" property that contains the keyval used for the mnemonic accelerator if one has been set on the label. If there is no mnemonic set up it returns the void symbol keyval.

gtk.Label.set_mnemonic_widget

    def set_mnemonic_widget(widget)

The set_mnemonic_widget() method sets the "mnemonic-widget" property using the value of widget. This method associates the label mnemonic with a widget that will be activated when the mnemonic accelerator is pressed. When the label is inside a widget (like a gtk.Button or a gtk.Notebook tab) it is automatically associated with the correct widget, but sometimes (i.e. when the target is a gtk.Entry next to the label) you need to set it explicitly using this function. The target widget will be activated by emitting "mnemonic_activate" on it.

gtk.Label.get_mnemonic_widget

    def get_mnemonic_widget()

The get_mnemonic_widget() method retrieves the value of the "mnemonic-widget" property which is the target of the mnemonic accelerator of this label. See set_mnemonic_widget().

gtk.Label.set_text_with_mnemonic

    def set_text_with_mnemonic(str)

The set_text_with_mnemonic() method sets the label's text from the string str. If characters in str are preceded by an underscore, they are underlined indicating that they represent a mnemonic accelerator. The mnemonic key can be used to activate another widget, chosen automatically, or explicitly using the set_mnemonic_widget() method.

gtk.Label.set_justify

    def set_justify(jtype)

The set_justify() method sets the alignment of the lines in the text of the label relative to each other using the value of jtype. The possible values of jtype are: gtk.JUSTIFY_LEFT, gtk.JUSTIFY_RIGHT, gtk.JUSTIFY_CENTER and gtk.JUSTIFY_FILL. gtk.JUSTIFY_LEFT is the default value when the widget is first created. If you want to set the alignment of the label as a whole, use the gtk.Misc.set_alignment() method instead. The set_justify() has no effect on labels containing only a single line.

gtk.Label.get_justify

    def get_justify()

The get_justify() method returns the justification of the label; one of: gtk.JUSTIFY_LEFT, gtk.JUSTIFY_RIGHT, gtk.JUSTIFY_CENTER or gtk.JUSTIFY_FILL. See set_justify().

gtk.Label.set_pattern

    def set_pattern(pattern)

The set_pattern() method sets the "pattern" property with the value of pattern. The pattern contains an underscore or space for each character in the label text. Any characters omitted are assumed to be spaces. For example, if the label text is "XXX Label" and the pattern is "___" then only the "XXX" will be underlined.

gtk.Label.set_line_wrap

    def set_line_wrap(wrap)

The set_wrap() method sets the "wrap" property tot he value of wrap. If wrap is True the label text will wrap if it is wider than the widget size; otherwise, the text gets cut off at the edge of the widget.

gtk.Label.get_line_wrap

    def get_line_wrap()

The get_line_wrap() method returns the value of the "wrap" property. If "wrap" is True the lines in the label are automatically wrapped. See set_line_wrap().

gtk.Label.set_selectable

    def set_selectable(setting)

The set_selectable() method sets the "selectable" property with the value of setting. If setting is True the user is allowed to select text from the label, for copy-and-paste.

gtk.Label.get_selectable

    def get_selectable()

The get_selectable() method gets the value of the "selectable" property set by the set_selectable() method.

gtk.Label.select_region

    def select_region(start_offset, end_offset)

The select_region() method selects a range of characters in the label, if the label is selectable. The selected region is the range of characters between start_offset and end_offset. See set_selectable(). If the label is not selectable, this method has no effect. If start_offset or end_offset are -1, then the end of the label will be substituted.

gtk.Label.get_selection_bounds

    def get_selection_bounds()

The get_selection_bounds() method returns a tuple that contains the start and end character offsets of the selected text in the label if the selection exists. If there is no selection or the label is not selectable, an empty tuple is returned.

gtk.Label.get_layout

    def get_layout()

The get_layout() method returns the pango.Layout used to display the label. The layout is useful to e.g. convert text positions to pixel positions, in combination with get_layout_offsets().

gtk.Label.get_layout_offsets

    def get_layout_offsets()

The get_layout_offsets() method returns a tuple containing the coordinates where the label will draw the pango.Layout representing the text in the label. This method is useful for converting mouse events into coordinates inside the pango.Layout, e.g. to take some action if some part of the label is clicked. Of course you will need to create a gtk.EventBox to receive the events, and pack the label inside it, since labels are a "windowless" (gtk.NO_WINDOW) widget. Remember when using the pango.Layout functions you need to convert to and from pixels using pango.PIXELS() or pango.SCALE.

gtk.Label.set_ellipsize

    def set_ellipsize(mode)

The set_ellipsize() method sets the "ellipsize" property to the value of mode. mode should be one of the Pango Ellipsize Mode Constants. The "ellipsize" property specifies if and where an ellipse should be used if there is not enough room for the label text.

gtk.Label.get_ellipsize

    def get_ellipsize()

The get_ellipsize() method returns the value of the "ellipsize" property which contains one of the Pango Ellipsize Mode Constants. The "ellipsize" property specifies if and where an ellipse should be used if there is not enough room for the label text.

gtk.Label.set_width_chars

    def set_width_chars(n_chars)

The set_width_chars() method sets the "width-chars" property to the value of n_chars. The "width-chars" property specifies the desired width of the label in characters.

gtk.Label.get_width_chars

    def get_width_chars()

The get_width_chars() method returns the value of the "width-chars" property that specifies the desired width of the label in characters.

gtk.Label.set_single_line_mode

    def set_single_line_mode(single_line_mode)

The set_single_line_mode() method sets the "single-line-mode" property to the value of single_line_mode. If single_line_mode is True the label is in single line mode where the height of the label does not depend on the actual text, it is always set to ascent + descent of the font.

gtk.Label.get_single_line_mode

    def get_single_line_mode()

The get_single_line_mode() method returns the value of the "single-line-mode" property. See the set_single_line_mode() method for more information.

gtk.Label.set_max_width_chars

    def set_max_width_chars(n_chars)

The set_max_width_chars() method sets the "max-width-chars" property to the value of n_chars.

gtk.Label.get_max_width_chars

    def get_max_width_chars()

The get_max_width_chars() method returns the value of the "max-width-chars" property which is the desired maximum width of the label in characters.

gtk.Label.set_angle

    def set_angle(angle)

The set_angle() method sets the "angle" property to the value of angle. angle is the angle of rotation for the label. An angle of 90 reads from from bottom to top, an angle of 270, from top to bottom. The angle setting for the label is ignored if the label is selectable, wrapped, or ellipsized.

gtk.Label.get_angle

    def get_angle()

The get_angle() method returns the value of the "angle" property. See the set_angle() method for more information.

The "copy-clipboard" gtk.Label Signal

    def callback(label, user_param1, ...)

The "copy-clipboard" signal is emitted when text is copied from the label to the clipboard.

The "move-cursor" gtk.Label Signal

    def callback(label, step, count, extend_selection, user_param1, ...)

The "move-cursor" signal is emitted when the cursor is being moved count steps or size step. The step size is one of:

  gtk.MOVEMENT_LOGICAL_POSITIONS,    move by graphemes
  gtk.MOVEMENT_VISUAL_POSITIONS,     move by graphemes
  gtk.MOVEMENT_WORDS,                move by words
  gtk.MOVEMENT_DISPLAY_LINES,        move by lines(wrapped lines)
  gtk.MOVEMENT_DISPLAY_LINE_ENDS,    move to line ends(wrapped lines)
  gtk.MOVEMENT_PARAGRAPHS,           move by paragraphs(newline-ended lines)
  gtk.MOVEMENT_PARAGRAPH_ENDS,       move to ends of a paragraph
  gtk.MOVEMENT_PAGES,	             move by pages
  gtk.MOVEMENT_BUFFER_ENDS           move to ends of the buffer

If extend_selection is True the selection will be extended to include the text moved over.

The "populate-popup" gtk.Label Signal

    def callback(label, menu, user_param1, ...)

The "populate-popup" signal is emitted when a menu needs to be populated on the fly.