"""Sample demo showing widget states and some font styling."""
import ttk
states = ['active', 'disabled', 'focus', 'pressed', 'selected',
'background', 'readonly', 'alternate', 'invalid']
for state in states[:]:
states.append("!" + state)
def reset_state(widget):
nostate = states[len(states) // 2:]
widget.state(nostate)
class App(ttk.Frame):
def __init__(self, title=None):
ttk.Frame.__init__(self, borderwidth=6)
self.master.title(title)
self.style = ttk.Style()
# get default font size and family
btn_font = self.style.lookup("TButton", "font")
fsize = str(self.tk.eval("font configure %s -size" % btn_font))
self.font_family = self.tk.eval("font configure %s -family" % btn_font)
if ' ' in self.font_family:
self.font_family = '{%s}' % self.font_family
self.fsize_prefix = fsize[0] if fsize[0] == '-' else ''
self.base_fsize = int(fsize[1 if fsize[0] == '-' else 0:])
# a list to hold all the widgets that will have their states changed
self.update_widgets = []
self._setup_widgets()
def _set_font(self, extra=0):
self.style.configure("TButton", font="%s %s%d" % (self.font_family,
self.fsize_prefix, self.base_fsize + extra))
def _new_state(self, widget, newtext):
widget = self.nametowidget(widget)
if not newtext:
goodstates = ["disabled"]
font_extra = 0
else:
# set widget state according to what has been entered in the entry
newstates = set(newtext.split()) # eliminate duplicates
# keep only the valid states
goodstates = [state for state in newstates if state in states]
# define a new font size based on amount of states
font_extra = 2 * len(goodstates)
# set new widget state
for widget in self.update_widgets:
reset_state(widget) # remove any previous state from the widget
widget.state(goodstates)
# update Ttk Button font size
self._set_font(font_extra)
return 1
def _setup_widgets(self):
btn = ttk.Button(self, text='Enter states and watch')
entry = ttk.Entry(self, cursor='xterm', validate="key")
entry['validatecommand'] = (self.register(self._new_state), '%W', '%P')
entry.focus()
self.update_widgets.append(btn)
entry.validate()
entry.pack(fill='x', padx=6)
btn.pack(side='left', pady=6, padx=6, anchor='n')
self.pack(fill='both', expand=1)
def main():
app = App("Widget State Tester")
app.mainloop()
if __name__ == "__main__":
main()
