blob: 225ec6d34def96b6948875e8ed4abc864ec6e841 [file] [log] [blame]
xf.li86118912025-03-19 20:07:27 -07001# Tkinter font wrapper
2#
3# written by Fredrik Lundh, February 1998
4#
5
6__version__ = "0.9"
7
8import itertools
9import tkinter
10
11
12# weight/slant
13NORMAL = "normal"
14ROMAN = "roman"
15BOLD = "bold"
16ITALIC = "italic"
17
18
19def nametofont(name):
20 """Given the name of a tk named font, returns a Font representation.
21 """
22 return Font(name=name, exists=True)
23
24
25class Font:
26 """Represents a named font.
27
28 Constructor options are:
29
30 font -- font specifier (name, system font, or (family, size, style)-tuple)
31 name -- name to use for this font configuration (defaults to a unique name)
32 exists -- does a named font by this name already exist?
33 Creates a new named font if False, points to the existing font if True.
34 Raises _tkinter.TclError if the assertion is false.
35
36 the following are ignored if font is specified:
37
38 family -- font 'family', e.g. Courier, Times, Helvetica
39 size -- font size in points
40 weight -- font thickness: NORMAL, BOLD
41 slant -- font slant: ROMAN, ITALIC
42 underline -- font underlining: false (0), true (1)
43 overstrike -- font strikeout: false (0), true (1)
44
45 """
46
47 counter = itertools.count(1)
48
49 def _set(self, kw):
50 options = []
51 for k, v in kw.items():
52 options.append("-"+k)
53 options.append(str(v))
54 return tuple(options)
55
56 def _get(self, args):
57 options = []
58 for k in args:
59 options.append("-"+k)
60 return tuple(options)
61
62 def _mkdict(self, args):
63 options = {}
64 for i in range(0, len(args), 2):
65 options[args[i][1:]] = args[i+1]
66 return options
67
68 def __init__(self, root=None, font=None, name=None, exists=False,
69 **options):
70 if not root:
71 root = tkinter._get_default_root('use font')
72 tk = getattr(root, 'tk', root)
73 if font:
74 # get actual settings corresponding to the given font
75 font = tk.splitlist(tk.call("font", "actual", font))
76 else:
77 font = self._set(options)
78 if not name:
79 name = "font" + str(next(self.counter))
80 self.name = name
81
82 if exists:
83 self.delete_font = False
84 # confirm font exists
85 if self.name not in tk.splitlist(tk.call("font", "names")):
86 raise tkinter._tkinter.TclError(
87 "named font %s does not already exist" % (self.name,))
88 # if font config info supplied, apply it
89 if font:
90 tk.call("font", "configure", self.name, *font)
91 else:
92 # create new font (raises TclError if the font exists)
93 tk.call("font", "create", self.name, *font)
94 self.delete_font = True
95 self._tk = tk
96 self._split = tk.splitlist
97 self._call = tk.call
98
99 def __str__(self):
100 return self.name
101
102 def __eq__(self, other):
103 if not isinstance(other, Font):
104 return NotImplemented
105 return self.name == other.name and self._tk == other._tk
106
107 def __getitem__(self, key):
108 return self.cget(key)
109
110 def __setitem__(self, key, value):
111 self.configure(**{key: value})
112
113 def __del__(self):
114 try:
115 if self.delete_font:
116 self._call("font", "delete", self.name)
117 except Exception:
118 pass
119
120 def copy(self):
121 "Return a distinct copy of the current font"
122 return Font(self._tk, **self.actual())
123
124 def actual(self, option=None, displayof=None):
125 "Return actual font attributes"
126 args = ()
127 if displayof:
128 args = ('-displayof', displayof)
129 if option:
130 args = args + ('-' + option, )
131 return self._call("font", "actual", self.name, *args)
132 else:
133 return self._mkdict(
134 self._split(self._call("font", "actual", self.name, *args)))
135
136 def cget(self, option):
137 "Get font attribute"
138 return self._call("font", "config", self.name, "-"+option)
139
140 def config(self, **options):
141 "Modify font attributes"
142 if options:
143 self._call("font", "config", self.name,
144 *self._set(options))
145 else:
146 return self._mkdict(
147 self._split(self._call("font", "config", self.name)))
148
149 configure = config
150
151 def measure(self, text, displayof=None):
152 "Return text width"
153 args = (text,)
154 if displayof:
155 args = ('-displayof', displayof, text)
156 return self._tk.getint(self._call("font", "measure", self.name, *args))
157
158 def metrics(self, *options, **kw):
159 """Return font metrics.
160
161 For best performance, create a dummy widget
162 using this font before calling this method."""
163 args = ()
164 displayof = kw.pop('displayof', None)
165 if displayof:
166 args = ('-displayof', displayof)
167 if options:
168 args = args + self._get(options)
169 return self._tk.getint(
170 self._call("font", "metrics", self.name, *args))
171 else:
172 res = self._split(self._call("font", "metrics", self.name, *args))
173 options = {}
174 for i in range(0, len(res), 2):
175 options[res[i][1:]] = self._tk.getint(res[i+1])
176 return options
177
178
179def families(root=None, displayof=None):
180 "Get font families (as a tuple)"
181 if not root:
182 root = tkinter._get_default_root('use font.families()')
183 args = ()
184 if displayof:
185 args = ('-displayof', displayof)
186 return root.tk.splitlist(root.tk.call("font", "families", *args))
187
188
189def names(root=None):
190 "Get names of defined fonts (as a tuple)"
191 if not root:
192 root = tkinter._get_default_root('use font.names()')
193 return root.tk.splitlist(root.tk.call("font", "names"))
194
195
196# --------------------------------------------------------------------
197# test stuff
198
199if __name__ == "__main__":
200
201 root = tkinter.Tk()
202
203 # create a font
204 f = Font(family="times", size=30, weight=NORMAL)
205
206 print(f.actual())
207 print(f.actual("family"))
208 print(f.actual("weight"))
209
210 print(f.config())
211 print(f.cget("family"))
212 print(f.cget("weight"))
213
214 print(names())
215
216 print(f.measure("hello"), f.metrics("linespace"))
217
218 print(f.metrics(displayof=root))
219
220 f = Font(font=("Courier", 20, "bold"))
221 print(f.measure("hello"), f.metrics("linespace", displayof=root))
222
223 w = tkinter.Label(root, text="Hello, world", font=f)
224 w.pack()
225
226 w = tkinter.Button(root, text="Quit!", command=root.destroy)
227 w.pack()
228
229 fb = Font(font=w["font"]).copy()
230 fb.config(weight=BOLD)
231
232 w.config(font=fb)
233
234 tkinter.mainloop()