'''Label
=====
.. image:: images/label.png
:align: right
The :class:`Label` widget is for rendering text::
# hello world text
l = Label(text='Hello world')
# unicode text; can only display glyphs that are available in the font
l = Label(text='Hello world ' + chr(2764))
# multiline text
l = Label(text='Multi\\nLine')
# size
l = Label(text='Hello world', font_size='20sp')
.. _kivy-uix-label-sizing-and-text-content:
Sizing and text content
---------------------------
By default, the size of :class:`Label` is not affected by :attr:`~Label.text`
content and the text is not affected by the size. In order to control
sizing, you must specify :attr:`~Label.text_size` to constrain the text
and/or bind :attr:`~Label.size` to :attr:`~Label.texture_size` to grow with
the text.
For example, this label's size will be set to the text content
(plus :attr:`~Label.padding`):
.. code-block:: kv
Label:
size: self.texture_size
This label's text will wrap at the specified width and be clipped to the
height:
.. code-block:: kv
Label:
text_size: cm(6), cm(4)
.. note:: The :attr:`~Label.shorten` and :attr:`~Label.max_lines` attributes
control how overflowing text behaves.
Combine these concepts to create a Label that can grow vertically but wraps the
text at a certain width:
.. code-block:: kv
Label:
text_size: root.width, None
size: self.texture_size
How to have a custom background color in the label:
.. code-block:: kv
# Define your background color Template
<BackgroundColor@Widget>
background_color: 1, 1, 1, 1
canvas.before:
Color:
rgba: root.background_color
Rectangle:
size: self.size
pos: self.pos
# Now you can simply Mix the `BackgroundColor` class with almost
# any other widget... to give it a background.
<BackgroundLabel@Label+BackgroundColor>
background_color: 0, 0, 0, 0
# Default the background color for this label
# to r 0, g 0, b 0, a 0
# Use the BackgroundLabel any where in your kv code like below
BackgroundLabel
text: 'Hello'
background_color: 1, 0, 0, 1
Text alignment and wrapping
---------------------------
The :class:`Label` has :attr:`~Label.halign` and :attr:`~Label.valign`
properties to control the alignment of its text. However, by default the text
image (:attr:`~Label.texture`) is only just large enough to contain the
characters and is positioned in the center of the Label. The valign property
will have no effect and halign will only have an effect if your text has
newlines; a single line of text will appear to be centered even though halign
is set to left (by default).
In order for the alignment properties to take effect, set the
:attr:`~Label.text_size`, which specifies the size of the bounding box within
which text is aligned. For instance, the following code binds this size to the
size of the Label, so text will be aligned within the widget bounds. This
will also automatically wrap the text of the Label to remain within this area.
.. code-block:: kv
Label:
text_size: self.size
halign: 'right'
valign: 'middle'
Markup text
-----------
.. versionadded:: 1.1.0
You can change the style of the text using :doc:`api-kivy.core.text.markup`.
The syntax is similar to the bbcode syntax but only the inline styling is
allowed::
# hello world with world in bold
l = Label(text='Hello [b]World[/b]', markup=True)
# hello in red, world in blue
l = Label(text='[color=ff3333]Hello[/color][color=3333ff]World[/color]',
markup = True)
If you need to escape the markup from the current text, use
:func:`kivy.utils.escape_markup`::
text = 'This is an important message [1]'
l = Label(text='[b]' + escape_markup(text) + '[/b]', markup=True)
The following tags are available:
``[b][/b]``
Activate bold text
``[i][/i]``
Activate italic text
``[u][/u]``
Underlined text
``[s][/s]``
Strikethrough text
``[font=<str>][/font]``
Change the font (note: this refers to a TTF file or registered alias)
``[font_context=<str>][/font_context]``
Change context for the font, use string value "none" for isolated context
(this is equivalent to `None`; if you created a font context named
`'none'`, it cannot be referred to using markup)
``[font_family=<str>][/font_family]``
Font family to request for drawing. This is only valid when using a
font context, see :class:`kivy.uix.label.Label` for details.
``[font_features=<str>][/font_features]``
OpenType font features, in CSS format, this is passed straight
through to Pango. The effects of requesting a feature depends on loaded
fonts, library versions, etc. Pango only, requires v1.38 or later.
``[size=<integer>][/size]``
Change the font size
``[color=#<color>][/color]``
Change the text color
``[ref=<str>][/ref]``
Add an interactive zone. The reference + bounding box inside the
reference will be available in :attr:`Label.refs`
``[anchor=<str>]``
Put an anchor in the text. You can get the position of your anchor within
the text with :attr:`Label.anchors`
``[sub][/sub]``
Display the text at a subscript position relative to the text before it.
``[sup][/sup]``
Display the text at a superscript position relative to the text before it.
``[text_language=<str>][/text_language]``
Language of the text, this is an RFC-3066 format language tag (as string),
for example "en_US", "zh_CN", "fr" or "ja". This can impact font selection
and metrics. Use the string "None" to revert to locale detection.
Pango only.
If you want to render the markup text with a [ or ] or & character, you need to
escape them. We created a simple syntax::
[ -> &bl;
] -> &br;
& -> &
Then you can write::
"[size=24]Hello &bl;World&br;[/size]"
Interactive zone in text
------------------------
.. versionadded:: 1.1.0
You can now have definable "links" using text markup. The idea is to be able
to detect when the user clicks on part of the text and to react.
The tag ``[ref=xxx]`` is used for that.
In this example, we are creating a reference on the word "World". When
this word is clicked, the function ``print_it`` will be called with the
name of the reference::
def print_it(instance, value):
print('User clicked on', value)
widget = Label(text='Hello [ref=world]World[/ref]', markup=True)
widget.bind(on_ref_press=print_it)
For prettier rendering, you could add a color for the reference. Replace the
``text=`` in the previous example with::
'Hello [ref=world][color=0000ff]World[/color][/ref]'
Catering for Unicode languages
------------------------------
The font kivy uses does not contain all the characters required for displaying
all languages. When you use the built-in widgets, this results in a block being
drawn where you expect a character.
If you want to display such characters, you can chose a font that supports them
and deploy it universally via kv:
.. code-block:: kv
<Label>:
font_name: '/<path>/<to>/<font>'
Note that this needs to be done before your widgets are loaded as kv rules are
only applied at load time.
Usage example
-------------
The following example marks the anchors and references contained in a label::
from kivy.app import App
from kivy.uix.label import Label
from kivy.clock import Clock
from kivy.graphics import Color, Rectangle
class TestApp(App):
@staticmethod
def get_x(label, ref_x):
""" Return the x value of the ref/anchor relative to the canvas """
return label.center_x - label.texture_size[0] * 0.5 + ref_x
@staticmethod
def get_y(label, ref_y):
""" Return the y value of the ref/anchor relative to the canvas """
# Note the inversion of direction, as y values start at the top of
# the texture and increase downwards
return label.center_y + label.texture_size[1] * 0.5 - ref_y
def show_marks(self, label):
# Indicate the position of the anchors with a red top marker
for name, anc in label.anchors.items():
with label.canvas:
Color(1, 0, 0)
Rectangle(pos=(self.get_x(label, anc[0]),
self.get_y(label, anc[1])),
size=(3, 3))
# Draw a green surround around the refs. Note the sizes y inversion
for name, boxes in label.refs.items():
for box in boxes:
with label.canvas:
Color(0, 1, 0, 0.25)
Rectangle(pos=(self.get_x(label, box[0]),
self.get_y(label, box[1])),
size=(box[2] - box[0],
box[1] - box[3]))
def build(self):
label = Label(
text='[anchor=a]a\\nChars [anchor=b]b\\n[ref=myref]ref[/ref]',
markup=True)
Clock.schedule_once(lambda dt: self.show_marks(label), 1)
return label
TestApp().run()
'''
__all__ = ('Label', )
from kivy.clock import Clock
from kivy.uix.widget import Widget
from kivy.core.text import Label as CoreLabel, DEFAULT_FONT
from kivy.core.text.markup import MarkupLabel as CoreMarkupLabel
from kivy.properties import StringProperty, OptionProperty, \
NumericProperty, BooleanProperty, ListProperty, \
ObjectProperty, DictProperty, ColorProperty, VariableListProperty
from kivy.utils import get_hex_from_color
[docs]class Label(Widget):
'''Label class, see module documentation for more information.
:Events:
`on_ref_press`
Fired when the user clicks on a word referenced with a
``[ref]`` tag in a text markup.
'''
__events__ = ['on_ref_press']
_font_properties = ('text', 'font_size', 'font_name', 'font_script_name',
'font_direction', 'bold', 'italic',
'underline', 'strikethrough', 'font_family', 'color',
'disabled_color', 'halign', 'valign', 'padding',
'outline_width', 'disabled_outline_color',
'outline_color', 'text_size', 'shorten', 'mipmap',
'line_height', 'max_lines', 'strip', 'shorten_from',
'split_str', 'ellipsis_options', 'unicode_errors',
'markup', 'font_hinting', 'font_kerning',
'font_blended', 'font_context', 'font_features',
'base_direction', 'text_language',
'limit_render_to_text_bbox')
def __init__(self, **kwargs):
self._trigger_texture = Clock.create_trigger(self.texture_update, -1)
super(Label, self).__init__(**kwargs)
# bind all the property for recreating the texture
d = Label._font_properties
fbind = self.fbind
update = self._trigger_texture_update
# NOTE: Compatibility code due to deprecated properties.
fbind('padding_x', update, 'padding_x')
fbind('padding_y', update, 'padding_y')
fbind('disabled', update, 'disabled')
for x in d:
fbind(x, update, x)
self._label = None
self._create_label()
# force the texture creation
self._trigger_texture()
def _create_label(self):
# create the core label class according to markup value
if self._label is not None:
cls = self._label.__class__
else:
cls = None
markup = self.markup
if (markup and cls is not CoreMarkupLabel) or \
(not markup and cls is not CoreLabel):
# markup have change, we need to change our rendering method.
dkw = {x: getattr(self, x) for x in self._font_properties}
dkw['usersize'] = self.text_size
if self.disabled:
dkw['color'] = self.disabled_color
dkw['outline_color'] = self.disabled_outline_color
if markup:
self._label = CoreMarkupLabel(**dkw)
else:
self._label = CoreLabel(**dkw)
def _trigger_texture_update(self, name=None, source=None, value=None):
# check if the label core class need to be switch to a new one
if name == 'markup':
self._create_label()
if source:
if name == 'text':
self._label.text = value
elif name == 'text_size':
self._label.usersize = value
elif name == 'font_size':
self._label.options[name] = value
elif name == 'disabled_color' and self.disabled:
self._label.options['color'] = value
elif name == 'disabled_outline_color' and self.disabled:
self._label.options['outline_color'] = value
elif name == 'disabled':
self._label.options['color'] = self.disabled_color if value \
else self.color
self._label.options['outline_color'] = (
self.disabled_outline_color if value else
self.outline_color)
# NOTE: Compatibility code due to deprecated properties
# Must be removed along with padding_x and padding_y
elif name == 'padding_x':
self._label.options['padding'][::2] = [value] * 2
elif name == 'padding_y':
self._label.options['padding'][1::2] = [value] * 2
else:
self._label.options[name] = value
self._trigger_texture()
[docs] def texture_update(self, *largs):
'''Force texture recreation with the current Label properties.
After this function call, the :attr:`texture` and :attr:`texture_size`
will be updated in this order.
'''
mrkup = self._label.__class__ is CoreMarkupLabel
self.texture = None
if (not self._label.text or
(self.halign == 'justify' or self.strip) and
not self._label.text.strip()):
self.texture_size = (0, 0)
self.is_shortened = False
if mrkup:
self.refs, self._label._refs = {}, {}
self.anchors, self._label._anchors = {}, {}
else:
if mrkup:
text = self.text
# we must strip here, otherwise, if the last line is empty,
# markup will retain the last empty line since it only strips
# line by line within markup
if self.halign == 'justify' or self.strip:
text = text.strip()
self._label.text = ''.join(('[color=',
get_hex_from_color(
self.disabled_color if
self.disabled else self.color),
']', text, '[/color]'))
self._label.refresh()
# force the rendering to get the references
if self._label.texture:
self._label.texture.bind()
self.refs = self._label.refs
self.anchors = self._label.anchors
else:
self._label.refresh()
texture = self._label.texture
if texture is not None:
self.texture = self._label.texture
self.texture_size = list(self.texture.size)
self.is_shortened = self._label.is_shortened
[docs] def on_touch_down(self, touch):
if super(Label, self).on_touch_down(touch):
return True
if not len(self.refs):
return False
tx, ty = touch.pos
tx -= self.center_x - self.texture_size[0] / 2.
ty -= self.center_y - self.texture_size[1] / 2.
ty = self.texture_size[1] - ty
for uid, zones in self.refs.items():
for zone in zones:
x, y, w, h = zone
if x <= tx <= w and y <= ty <= h:
self.dispatch('on_ref_press', uid)
return True
return False
def on_ref_press(self, ref):
pass
#
# Properties
#
disabled_color = ColorProperty([1, 1, 1, .3])
'''The color of the text when the widget is disabled, in the (r, g, b, a)
format.
.. versionadded:: 1.8.0
:attr:`disabled_color` is a :class:`~kivy.properties.ColorProperty` and
defaults to [1, 1, 1, .3].
.. versionchanged:: 2.0.0
Changed from :class:`~kivy.properties.ListProperty` to
:class:`~kivy.properties.ColorProperty`.
'''
text = StringProperty('')
'''Text of the label.
Creation of a simple hello world::
widget = Label(text='Hello world')
:attr:`text` is a :class:`~kivy.properties.StringProperty` and defaults to
''.
'''
text_size = ListProperty([None, None])
'''By default, the label is not constrained to any bounding box.
You can set the size constraint of the label with this property.
The text will autoflow into the constraints. So although the font size
will not be reduced, the text will be arranged to fit into the box as best
as possible, with any text still outside the box clipped.
This sets and clips :attr:`texture_size` to text_size if not None.
.. versionadded:: 1.0.4
For example, whatever your current widget size is, if you want the label to
be created in a box with width=200 and unlimited height::
Label(text='Very big big line', text_size=(200, None))
.. note::
This text_size property is the same as the
:attr:`~kivy.core.text.Label.usersize` property in the
:class:`~kivy.core.text.Label` class. (It is named size= in the
constructor.)
:attr:`text_size` is a :class:`~kivy.properties.ListProperty` and
defaults to (None, None), meaning no size restriction by default.
'''
base_direction = OptionProperty(None,
options=['ltr', 'rtl', 'weak_rtl', 'weak_ltr', None],
allownone=True)
'''Base direction of text, this impacts horizontal alignment when
:attr:`halign` is `auto` (the default). Available options are: None,
"ltr" (left to right), "rtl" (right to left) plus "weak_ltr" and
"weak_rtl".
.. note::
This feature requires the Pango text provider.
.. note::
Weak modes are currently not implemented in Kivy text layout, and
have the same effect as setting strong mode.
.. versionadded:: 1.11.0
:attr:`base_direction` is an :class:`~kivy.properties.OptionProperty` and
defaults to None (autodetect RTL if possible, otherwise LTR).
'''
text_language = StringProperty(None, allownone=True)
'''Language of the text, if None Pango will determine it from locale.
This is an RFC-3066 format language tag (as a string), for example
"en_US", "zh_CN", "fr" or "ja". This can impact font selection, metrics
and rendering. For example, the same bytes of text can look different
for `ur` and `ar` languages, though both use Arabic script.
.. note::
This feature requires the Pango text provider.
.. versionadded:: 1.11.0
:attr:`text_language` is a :class:`~kivy.properties.StringProperty` and
defaults to None.
'''
font_context = StringProperty(None, allownone=True)
'''Font context. `None` means the font is used in isolation, so you are
guaranteed to be drawing with the TTF file resolved by :attr:`font_name`.
Specifying a value here will load the font file into a named context,
enabling fallback between all fonts in the same context. If a font
context is set, you are not guaranteed that rendering will actually use
the specified TTF file for all glyphs (Pango will pick the one it
thinks is best).
If Kivy is linked against a system-wide installation of FontConfig,
you can load the system fonts by specifying a font context starting
with the special string `system://`. This will load the system
fontconfig configuration, and add your application-specific fonts on
top of it (this imposes a significant risk of family name collision,
Pango may not use your custom font file, but pick one from the system)
.. note::
This feature requires the Pango text provider.
.. versionadded:: 1.11.0
:attr:`font_context` is a :class:`~kivy.properties.StringProperty` and
defaults to None.
'''
font_family = StringProperty(None, allownone=True)
'''Font family, this is only applicable when using :attr:`font_context`
option. The specified font family will be requested, but note that it may
not be available, or there could be multiple fonts registered with the
same family. The value can be a family name (string) available in the
font context (for example a system font in a `system://` context, or a
custom font file added using :class:`kivy.core.text.FontContextManager`).
If set to `None`, font selection is controlled by the :attr:`font_name`
setting.
.. note::
If using :attr:`font_name` to reference a custom font file, you
should leave this as `None`. The family name is managed automatically
in this case.
.. note::
This feature requires the Pango text provider.
.. versionadded:: 1.11.0
:attr:`font_family` is a :class:`~kivy.properties.StringProperty` and
defaults to None.
'''
font_name = StringProperty(DEFAULT_FONT)
'''Filename of the font to use. The path can be absolute or relative.
Relative paths are resolved by the :func:`~kivy.resources.resource_find`
function.
.. warning::
Depending of your text provider, the font file can be ignored. However,
you can mostly use this without problems.
If the font used lacks the glyphs for the particular language/symbols
you are using, you will see '[]' blank box characters instead of the
actual glyphs. The solution is to use a font that has the glyphs you
need to display. For example, to display |unicodechar|, use a font such
as freesans.ttf that has the glyph.
.. |unicodechar| image:: images/unicode-char.png
:attr:`font_name` is a :class:`~kivy.properties.StringProperty` and
defaults to 'Roboto'. This value is taken
from :class:`~kivy.config.Config`.
'''
font_script_name = OptionProperty('Latn', options=['Zyyy', 'Latn', 'Hani',
'Cyrl', 'Hira', 'Kana', 'Thai', 'Arab', 'Hang', 'Deva', 'Grek',
'Hebr', 'Taml', 'Knda', 'Geor', 'Mlym', 'Telu', 'Mymr', 'Gujr',
'Beng', 'Guru', 'Laoo', 'Zinh', 'Khmr', 'Tibt', 'Sinh', 'Ethi',
'Thaa', 'Orya', 'Zzzz', 'Cans', 'Syrc', 'Bopo', 'Nkoo', 'Cher',
'Yiii', 'Samr', 'Copt', 'Mong', 'Glag', 'Vaii', 'Bali', 'Tfng',
'Bamu', 'Batk', 'Cham', 'Java', 'Kali', 'Lepc', 'Limb', 'Lisu',
'Mand', 'Mtei', 'Talu', 'Olck', 'Saur', 'Sund', 'Sylo', 'Tale',
'Lana', 'Avst', 'Brah', 'Bugi', 'Buhd', 'Cari', 'Xsux', 'Cprt',
'Dsrt', 'Egyp', 'Goth', 'Hano', 'Armi', 'Phli', 'Prti', 'Kthi',
'Khar', 'Linb', 'Lyci', 'Lydi', 'Ogam', 'Ital', 'Xpeo', 'Sarb',
'Orkh', 'Osma', 'Phag', 'Phnx', 'Rjng', 'Runr', 'Shaw', 'Tglg',
'Tagb', 'Ugar', 'Cakm', 'Merc', 'Mero', 'Plrd', 'Shrd', 'Sora',
'Takr', 'Brai', 'Aghb', 'Bass', 'Dupl', 'Elba', 'Gran', 'Khoj',
'Lina', 'Mahj', 'Mani', 'Modi', 'Mroo', 'Narb', 'Nbat', 'Palm',
'Pauc', 'Perm', 'Phlp', 'Sidd', 'Sind', 'Tirh', 'Wara', 'Ahom',
'Hluw', 'Hatr', 'Mult', 'Hung', 'Sgnw', 'Adlm', 'Bhks', 'Marc',
'Osge', 'Tang', 'Newa', 'Gonm', 'Nshu', 'Soyo', 'Zanb', 'Dogr',
'Gong', 'Rohg', 'Maka', 'Medf', 'Sogo', 'Sogd', 'Elym', 'Hmnp',
'Nand', 'Wcho', 'Chrs', 'Diak', 'Kits', 'Yezi', 'Cpmn', 'Ougr',
'Tnsa', 'Toto', 'Vith', 'Kawi', 'Nagm'])
'''`script_code` from https://bit.ly/TypeScriptCodes .
.. versionadded:: 2.2.0
.. warning::
font_script_name is only currently supported in SDL2 ttf providers.
:attr:`font_script_name` is a :class:`~kivy.properties.OptionProperty` and
defaults to 'Latn'.
'''
font_direction = OptionProperty('ltr', options=['rtl', 'ltr', 'ttb', 'btt'])
'''Direction for the specific font, can be one of `ltr`, `rtl`, `ttb`,`btt`.
font_direction currently only works with SDL2 ttf providers.
.. versionadded:: 2.2.0
:attr:`font_direction` is a :class:`~kivy.properties.OptionProperty` and
defults to 'ltr'. '''
font_size = NumericProperty('15sp')
'''Font size of the text, in pixels.
:attr:`font_size` is a :class:`~kivy.properties.NumericProperty` and
defaults to 15sp.
'''
font_features = StringProperty()
'''OpenType font features, in CSS format, this is passed straight
through to Pango. The effects of requesting a feature depends on loaded
fonts, library versions, etc. For a complete list of features, see:
https://en.wikipedia.org/wiki/List_of_typographic_features
.. note::
This feature requires the Pango text provider, and Pango library
v1.38 or later.
.. versionadded:: 1.11.0
:attr:`font_features` is a :class:`~kivy.properties.StringProperty` and
defaults to an empty string.
'''
line_height = NumericProperty(1.0)
'''Line Height for the text. e.g. line_height = 2 will cause the spacing
between lines to be twice the size.
:attr:`line_height` is a :class:`~kivy.properties.NumericProperty` and
defaults to 1.0.
.. versionadded:: 1.5.0
'''
bold = BooleanProperty(False)
'''Indicates use of the bold version of your font.
.. note::
Depending of your font, the bold attribute may have no impact on your
text rendering.
:attr:`bold` is a :class:`~kivy.properties.BooleanProperty` and defaults to
False.
'''
italic = BooleanProperty(False)
'''Indicates use of the italic version of your font.
.. note::
Depending of your font, the italic attribute may have no impact on your
text rendering.
:attr:`italic` is a :class:`~kivy.properties.BooleanProperty` and defaults
to False.
'''
underline = BooleanProperty(False)
'''Adds an underline to the text.
.. note::
This feature requires the SDL2 text provider.
.. versionadded:: 1.10.0
:attr:`underline` is a :class:`~kivy.properties.BooleanProperty` and
defaults to False.
'''
strikethrough = BooleanProperty(False)
'''Adds a strikethrough line to the text.
.. note::
This feature requires the SDL2 text provider.
.. versionadded:: 1.10.0
:attr:`strikethrough` is a :class:`~kivy.properties.BooleanProperty` and
defaults to False.
'''
padding_x = NumericProperty(0, deprecated=True)
'''Horizontal padding of the text inside the widget box.
:attr:`padding_x` is a :class:`~kivy.properties.NumericProperty` and
defaults to 0.
.. versionchanged:: 1.9.0
`padding_x` has been fixed to work as expected.
In the past, the text was padded by the negative of its values.
.. deprecated:: 2.2.0
Please use :attr:`padding` instead.
'''
padding_y = NumericProperty(0, deprecated=True)
'''Vertical padding of the text inside the widget box.
:attr:`padding_y` is a :class:`~kivy.properties.NumericProperty` and
defaults to 0.
.. versionchanged:: 1.9.0
`padding_y` has been fixed to work as expected.
In the past, the text was padded by the negative of its values.
.. deprecated:: 2.2.0
Please use :attr:`padding` instead.
'''
padding = VariableListProperty([0, 0, 0, 0], lenght=4)
'''Padding of the text in the format [padding_left, padding_top,
padding_right, padding_bottom]
``padding`` also accepts a two argument form [padding_horizontal,
padding_vertical] and a one argument form [padding].
.. versionchanged:: 2.2.0
Replaced ReferenceListProperty with VariableListProperty.
:attr:`padding` is a :class:`~kivy.properties.VariableListProperty` and
defaults to [0, 0, 0, 0].
'''
halign = OptionProperty('auto', options=['left', 'center', 'right',
'justify', 'auto'])
'''Horizontal alignment of the text.
:attr:`halign` is an :class:`~kivy.properties.OptionProperty` and
defaults to 'auto'. Available options are : auto, left, center, right and
justify. Auto will attempt to autodetect horizontal alignment for RTL text
(Pango only), otherwise it behaves like `left`.
.. warning::
This doesn't change the position of the text texture of the Label
(centered), only the position of the text in this texture. You probably
want to bind the size of the Label to the :attr:`texture_size` or set a
:attr:`text_size`.
.. versionchanged:: 1.10.1
Added `auto` option
.. versionchanged:: 1.6.0
A new option was added to :attr:`halign`, namely `justify`.
'''
valign = OptionProperty('bottom',
options=['bottom', 'middle', 'center', 'top'])
'''Vertical alignment of the text.
:attr:`valign` is an :class:`~kivy.properties.OptionProperty` and defaults
to 'bottom'. Available options are : `'bottom'`,
`'middle'` (or `'center'`) and `'top'`.
.. versionchanged:: 1.10.0
The `'center'` option has been added as an alias of `'middle'`.
.. warning::
This doesn't change the position of the text texture of the Label
(centered), only the position of the text within this texture. You
probably want to bind the size of the Label to the :attr:`texture_size`
or set a :attr:`text_size` to change this behavior.
'''
color = ColorProperty([1, 1, 1, 1])
'''Text color, in the format (r, g, b, a).
:attr:`color` is a :class:`~kivy.properties.ColorProperty` and defaults to
[1, 1, 1, 1].
.. versionchanged:: 2.0.0
Changed from :class:`~kivy.properties.ListProperty` to
:class:`~kivy.properties.ColorProperty`.
'''
outline_width = NumericProperty(None, allownone=True)
'''Width in pixels for the outline around the text. No outline will be
rendered if the value is None.
.. note::
This feature requires the SDL2 text provider.
.. versionadded:: 1.10.0
:attr:`outline_width` is a :class:`~kivy.properties.NumericProperty` and
defaults to None.
'''
outline_color = ColorProperty([0, 0, 0, 1])
'''The color of the text outline, in the (r, g, b) format.
.. note::
This feature requires the SDL2 text provider.
.. versionadded:: 1.10.0
:attr:`outline_color` is a :class:`~kivy.properties.ColorProperty` and
defaults to [0, 0, 0, 1].
.. versionchanged:: 2.0.0
Changed from :class:`~kivy.properties.ListProperty` to
:class:`~kivy.properties.ColorProperty`. Alpha component is ignored
and assigning value to it has no effect.
'''
disabled_outline_color = ColorProperty([0, 0, 0, 1])
'''The color of the text outline when the widget is disabled, in the
(r, g, b) format.
.. note::
This feature requires the SDL2 text provider.
.. versionadded:: 1.10.0
:attr:`disabled_outline_color` is a :class:`~kivy.properties.ColorProperty`
and defaults to [0, 0, 0].
.. versionchanged:: 2.0.0
Changed from :class:`~kivy.properties.ListProperty` to
:class:`~kivy.properties.ColorProperty`. Alpha component is ignored
and assigning value to it has no effect.
'''
texture = ObjectProperty(None, allownone=True)
'''Texture object of the text.
The text is rendered automatically when a property changes. The OpenGL
texture created in this operation is stored in this property. You can use
this :attr:`texture` for any graphics elements.
Depending on the texture creation, the value will be a
:class:`~kivy.graphics.texture.Texture` or
:class:`~kivy.graphics.texture.TextureRegion` object.
.. warning::
The :attr:`texture` update is scheduled for the next frame. If you need
the texture immediately after changing a property, you have to call
the :meth:`texture_update` method before accessing :attr:`texture`::
l = Label(text='Hello world')
# l.texture is good
l.font_size = '50sp'
# l.texture is not updated yet
l.texture_update()
# l.texture is good now.
:attr:`texture` is an :class:`~kivy.properties.ObjectProperty` and defaults
to None.
'''
texture_size = ListProperty([0, 0])
'''Texture size of the text. The size is determined by the font size and
text. If :attr:`text_size` is [None, None], the texture will be the size
required to fit the text, otherwise it's clipped to fit :attr:`text_size`.
When :attr:`text_size` is [None, None], one can bind to texture_size
and rescale it proportionally to fit the size of the label in order to
make the text fit maximally in the label.
.. warning::
The :attr:`texture_size` is set after the :attr:`texture`
property. If you listen for changes to :attr:`texture`,
:attr:`texture_size` will not be up-to-date in your callback.
Bind to :attr:`texture_size` instead.
'''
mipmap = BooleanProperty(False)
'''Indicates whether OpenGL mipmapping is applied to the texture or not.
Read :ref:`mipmap` for more information.
.. versionadded:: 1.0.7
:attr:`mipmap` is a :class:`~kivy.properties.BooleanProperty` and defaults
to False.
'''
shorten = BooleanProperty(False)
'''
Indicates whether the label should attempt to shorten its textual contents
as much as possible if a :attr:`text_size` is given. Setting this to True
without an appropriately set :attr:`text_size` will lead to unexpected
results.
:attr:`shorten_from` and :attr:`split_str` control the direction from
which the :attr:`text` is split, as well as where in the :attr:`text` we
are allowed to split.
:attr:`shorten` is a :class:`~kivy.properties.BooleanProperty` and defaults
to False.
'''
shorten_from = OptionProperty('center', options=['left', 'center',
'right'])
'''The side from which we should shorten the text from, can be left,
right, or center.
For example, if left, the ellipsis will appear towards the left side and we
will display as much text starting from the right as possible. Similar to
:attr:`shorten`, this option only applies when :attr:`text_size` [0] is
not None, In this case, the string is shortened to fit within the specified
width.
.. versionadded:: 1.9.0
:attr:`shorten_from` is a :class:`~kivy.properties.OptionProperty` and
defaults to `center`.
'''
is_shortened = BooleanProperty(False)
'''This property indicates if :attr:`text` was rendered with or without
shortening when :attr:`shorten` is True.
.. versionadded:: 1.10.0
:attr:`is_shortened` is a :class:`~kivy.properties.BooleanProperty` and
defaults to False.
'''
split_str = StringProperty('')
'''The string used to split the :attr:`text` while shortening the string
when :attr:`shorten` is True.
For example, if it's a space, the string will be broken into words and as
many whole words that can fit into a single line will be displayed. If
:attr:`split_str` is the empty string, `''`, we split on every character
fitting as much text as possible into the line.
.. versionadded:: 1.9.0
:attr:`split_str` is a :class:`~kivy.properties.StringProperty` and
defaults to `''` (the empty string).
'''
ellipsis_options = DictProperty({})
'''Font options for the ellipsis string('...') used to split the text.
Accepts a dict as option name with the value. Only applied when
:attr:`markup` is true and text is shortened. All font options which work
for :class:`Label` will work for :attr:`ellipsis_options`. Defaults for
the options not specified are taken from the surronding text.
.. code-block:: kv
Label:
text: 'Some very long line which will be cut'
markup: True
shorten: True
ellipsis_options: {'color':(1,0.5,0.5,1),'underline':True}
.. versionadded:: 2.0.0
:attr:`ellipsis_options` is a :class:`~kivy.properties.DictProperty` and
defaults to `{}` (the empty dict).
'''
unicode_errors = OptionProperty(
'replace', options=('strict', 'replace', 'ignore'))
'''How to handle unicode decode errors. Can be `'strict'`, `'replace'` or
`'ignore'`.
.. versionadded:: 1.9.0
:attr:`unicode_errors` is an :class:`~kivy.properties.OptionProperty` and
defaults to `'replace'`.
'''
markup = BooleanProperty(False)
'''
.. versionadded:: 1.1.0
If True, the text will be rendered using the
:class:`~kivy.core.text.markup.MarkupLabel`: you can change the
style of the text using tags. Check the
:doc:`api-kivy.core.text.markup` documentation for more information.
:attr:`markup` is a :class:`~kivy.properties.BooleanProperty` and defaults
to False.
'''
refs = DictProperty({})
'''
.. versionadded:: 1.1.0
List of ``[ref=xxx]`` markup items in the text with the bounding box of
all the words contained in a ref, available only after rendering.
For example, if you wrote::
Check out my [ref=hello]link[/ref]
The refs will be set with::
{'hello': ((64, 0, 78, 16), )}
The references marked "hello" have a bounding box at (x1, y1, x2, y2).
These coordinates are relative to the top left corner of the text, with
the y value increasing downwards. You can define multiple refs with the
same name: each occurrence will be added as another (x1, y1, x2, y2) tuple
to this list.
The current Label implementation uses these references if they exist in
your markup text, automatically doing the collision with the touch and
dispatching an `on_ref_press` event.
You can bind a ref event like this::
def print_it(instance, value):
print('User click on', value)
widget = Label(text='Hello [ref=world]World[/ref]', markup=True)
widget.bind(on_ref_press=print_it)
.. note::
This works only with markup text. You need :attr:`markup` set to
True.
'''
anchors = DictProperty({})
'''
.. versionadded:: 1.1.0
Position of all the ``[anchor=xxx]`` markup in the text.
These coordinates are relative to the top left corner of the text, with
the y value increasing downwards. Anchors names should be unique and only
the first occurrence of any duplicate anchors will be recorded.
You can place anchors in your markup text as follows::
text = """
[anchor=title1][size=24]This is my Big title.[/size]
[anchor=content]Hello world
"""
Then, all the ``[anchor=]`` references will be removed and you'll get all
the anchor positions in this property (only after rendering)::
>>> widget = Label(text=text, markup=True)
>>> widget.texture_update()
>>> widget.anchors
{"content": (20, 32), "title1": (20, 16)}
.. note::
This works only with markup text. You need :attr:`markup` set to
True.
'''
max_lines = NumericProperty(0)
'''Maximum number of lines to use, defaults to 0, which means unlimited.
Please note that :attr:`shorten` take over this property. (with
shorten, the text is always one line.)
.. versionadded:: 1.8.0
:attr:`max_lines` is a :class:`~kivy.properties.NumericProperty` and
defaults to 0.
'''
strip = BooleanProperty(False)
'''Whether leading and trailing spaces and newlines should be stripped from
each displayed line. If True, every line will start at the right or left
edge, depending on :attr:`halign`. If :attr:`halign` is `justify` it is
implicitly True.
.. versionadded:: 1.9.0
:attr:`strip` is a :class:`~kivy.properties.BooleanProperty` and
defaults to False.
'''
font_hinting = OptionProperty(
'normal', options=[None, 'normal', 'light', 'mono'], allownone=True)
'''What hinting option to use for font rendering.
Can be one of `'normal'`, `'light'`, `'mono'` or None.
.. note::
This feature requires SDL2 or Pango text provider.
.. versionadded:: 1.10.0
:attr:`font_hinting` is an :class:`~kivy.properties.OptionProperty` and
defaults to `'normal'`.
'''
font_kerning = BooleanProperty(True)
'''Whether kerning is enabled for font rendering. You should normally
only disable this if rendering is broken with a particular font file.
.. note::
This feature requires the SDL2 text provider.
.. versionadded:: 1.10.0
:attr:`font_kerning` is a :class:`~kivy.properties.BooleanProperty` and
defaults to True.
'''
font_blended = BooleanProperty(True)
'''Whether blended or solid font rendering should be used.
.. note::
This feature requires the SDL2 text provider.
.. versionadded:: 1.10.0
:attr:`font_blended` is a :class:`~kivy.properties.BooleanProperty` and
defaults to True.
'''
limit_render_to_text_bbox = BooleanProperty(False)
'''If set to ``True``, this parameter indicates that rendering should be
limited to the bounding box of the text, excluding any additional white
spaces designated for ascent and descent.
By limiting the rendering to the bounding box of the text, it ensures a
more precise alignment with surrounding elements when utilizing properties
such as `valign`, `y`, `pos`, `pos_hint`, etc.
.. note::
This feature requires the PIL text provider.
:attr:`limit_render_to_text_bbox` is a
:class:`~kivy.properties.BooleanProperty` and defaults to False.
'''
