Fredrik Lundh's font wrapper.

Lib/lib-tk/tkFont.py

+#
+# Tkinter
+# $Id$
+#
+# font wrapper
+#
+# written by Fredrik Lundh <fredrik@pythonware.com>, February 1998
+#
+# FIXME: should add 'displayof' option where relevant (actual, families,
+#        measure, and metrics)
+# 
+# Copyright (c) Secret Labs AB 1998.
+#
+# info@pythonware.com
+# http://www.pythonware.com
+#
+
+__version__ = "0.9"
+
+import Tkinter
+import string
+
+# weight/slant
+NORMAL = "normal"
+BOLD   = "bold"
+ITALIC = "italic"
+
+class Font:
+
+    """Represents a named font.
+
+    Constructor options are:
+
+    font -- font specifier (name, system font, or (family, size, style)-tuple)
+
+       or any combination of
+
+    family -- font 'family', e.g. Courier, Times, Helvetica
+    size -- font size in points
+    weight -- font thickness: NORMAL, BOLD
+    slant -- font slant: NORMAL, ITALIC
+    underline -- font underlining: false (0), true (1)
+    overstrike -- font strikeout: false (0), true (1)
+    name -- name to use for this font configuration (defaults to a unique name)
+    """
+
+    def _set(self, kw):
+        options = []
+        for k, v in kw.items():
+            options.append("-"+k)
+            options.append(str(v))
+        return tuple(options)
+
+    def _get(self, args):
+      options = []
+      for k in args:
+          options.append("-"+k)
+      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, **options):
+        if not root:
+            root = Tkinter._default_root
+        if font:
+            # get actual settings corresponding to the given font
+            font = root.tk.splitlist(root.tk.call("font", "actual", font))
+        else:
+            font = self._set(options)
+        if not name:
+            name = "font" + str(id(self))
+        self.name = name
+        apply(root.tk.call, ("font", "create", name) + font)
+        # backlinks!
+        self._root  = root
+        self._split = root.tk.splitlist
+        self._call  = root.tk.call
+
+    def __str__(self):
+        return self.name
+
+    def __del__(self):
+        try:
+            self._call("font", "delete", self.name)
+        except (AttributeError, Tkinter.TclError):
+            pass
+
+    def copy(self):
+        "Return a distinct copy of the current font"
+        return apply(Font, (self._root,), self.actual())
+
+    def actual(self, option=None):
+        "Return actual font attributes"
+        if option:
+            return self._call("font", "actual", self.name, "-"+option)
+        else:
+            return self._mkdict(
+                self._split(self._call("font", "actual", self.name))
+                )
+
+    def cget(self, option):
+        "Get font attribute"
+        return self._call("font", "config", self.name, "-"+option)
+
+    def config(self, **options):
+        "Modify font attributes"
+        if options:
+            apply(self._call, ("font", "config", self.name) +
+                  self._set(options))
+        else:
+            return self._mkdict(
+                self._split(self._call("font", "config", self.name))
+                )
+
+    configure = config
+    
+    def measure(self, text):
+        "Return text width"
+        return string.atoi(self._call("font", "measure", self.name, 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 string.atoi(
+                self._call("font", "metrics", self.name, self._get(options))
+                )
+        else:
+            res = self._split(self._call("font", "metrics", self.name))
+            options = {}
+            for i in range(0, len(res), 2):
+                options[res[i][1:]] = string.atoi(res[i+1])
+            return options
+
+def families(root=None):
+    "Get font families (as a tuple)"
+    if not root:
+        root = Tkinter._default_root
+    return root.tk.splitlist(root.tk.call("font", "families"))     
+
+def names(root=None):
+    "Get names of defined fonts (as a tuple)"
+    if not root:
+        root = Tkinter._default_root
+    return root.tk.splitlist(root.tk.call("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.pack()
+
+    w = Tkinter.Button(root, text="Quit!", command=root.destroy)
+    w.pack()
+
+    fb = Font(font=w["font"]).copy()
+    fb.config(weight=BOLD)
+    
+    w.config(font=fb)
+
+    Tkinter.mainloop()