shithub: plan9front

ref: e72da62915b09d5673b0c0179ba8dfe045aeb8c3
dir: /sys/lib/python/lib-tk/

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# Tkinter font wrapper
# written by Fredrik Lundh, February 1998
# FIXME: should add 'displayof' option where relevant (actual, families,
#        measure, and metrics)

__version__ = "0.9"

import Tkinter

# weight/slant
NORMAL = "normal"
ROMAN = "roman"
BOLD   = "bold"
ITALIC = "italic"

def nametofont(name):
    """Given the name of a tk named font, returns a Font representation.
    return Font(name=name, exists=True)

class Font:

    """Represents a named font.

    Constructor options are:

    font -- font specifier (name, system font, or (family, size, style)-tuple)
    name -- name to use for this font configuration (defaults to a unique name)
    exists -- does a named font by this name already exist?
       Creates a new named font if False, points to the existing font if True.
       Raises _tkinter.TclError if the assertion is false.

       the following are ignored if font is specified:

    family -- font 'family', e.g. Courier, Times, Helvetica
    size -- font size in points
    weight -- font thickness: NORMAL, BOLD
    slant -- font slant: ROMAN, ITALIC
    underline -- font underlining: false (0), true (1)
    overstrike -- font strikeout: false (0), true (1)


    def _set(self, kw):
        options = []
        for k, v in kw.items():
        return tuple(options)

    def _get(self, args):
        options = []
        for k in args:
        return tuple(options)

    def _mkdict(self, args):
        options = {}
        for i in range(0, len(args), 2):
            options[args[i][1:]] = args[i+1]
        return options

    def __init__(self, root=None, font=None, name=None, exists=False, **options):
        if not root:
            root = Tkinter._default_root
        if font:
            # get actual settings corresponding to the given font
            font ="font", "actual", font))
            font = self._set(options)
        if not name:
            name = "font" + str(id(self)) = name

        if exists:
            self.delete_font = False
            # confirm font exists
            if not in"font", "names"):
                raise Tkinter._tkinter.TclError, "named font %s does not already exist" % (,)
            # if font config info supplied, apply it
            if font:
      "font", "configure",, *font)
            # create new font (raises TclError if the font exists)
  "font", "create",, *font)
            self.delete_font = True
        # backlinks!
        self._root  = root
        self._split =
        self._call  =

    def __str__(self):

    def __eq__(self, other):
        return == and isinstance(other, Font)

    def __getitem__(self, key):
        return self.cget(key)

    def __setitem__(self, key, value):
        self.configure(**{key: value})

    def __del__(self):
            if self.delete_font:
                self._call("font", "delete",
        except (KeyboardInterrupt, SystemExit):
        except Exception:

    def copy(self):
        "Return a distinct copy of the current font"
        return Font(self._root, **self.actual())

    def actual(self, option=None):
        "Return actual font attributes"
        if option:
            return self._call("font", "actual",, "-"+option)
            return self._mkdict(
                self._split(self._call("font", "actual",

    def cget(self, option):
        "Get font attribute"
        return self._call("font", "config",, "-"+option)

    def config(self, **options):
        "Modify font attributes"
        if options:
            self._call("font", "config",,
            return self._mkdict(
                self._split(self._call("font", "config",

    configure = config

    def measure(self, text):
        "Return text width"
        return int(self._call("font", "measure",, text))

    def metrics(self, *options):
        """Return font metrics.

        For best performance, create a dummy widget
        using this font before calling this method."""

        if options:
            return int(
                self._call("font", "metrics",, self._get(options))
            res = self._split(self._call("font", "metrics",
            options = {}
            for i in range(0, len(res), 2):
                options[res[i][1:]] = int(res[i+1])
            return options

def families(root=None):
    "Get font families (as a tuple)"
    if not root:
        root = Tkinter._default_root
    return"font", "families"))

def names(root=None):
    "Get names of defined fonts (as a tuple)"
    if not root:
        root = Tkinter._default_root
    return"font", "names"))

# --------------------------------------------------------------------
# test stuff

if __name__ == "__main__":

    root = Tkinter.Tk()

    # create a font
    f = Font(family="times", size=30, weight=NORMAL)

    print f.actual()
    print f.actual("family")
    print f.actual("weight")

    print f.config()
    print f.cget("family")
    print f.cget("weight")

    print names()

    print f.measure("hello"), f.metrics("linespace")

    print f.metrics()

    f = Font(font=("Courier", 20, "bold"))
    print f.measure("hello"), f.metrics("linespace")

    w = Tkinter.Label(root, text="Hello, world", font=f)

    w = Tkinter.Button(root, text="Quit!", command=root.destroy)

    fb = Font(font=w["font"]).copy()