Demo/tkinter/ttk/widget_state.py

   1 """Sample demo showing widget states and some font styling."""
   2 import ttk
   3
   4 states = ['active', 'disabled', 'focus', 'pressed', 'selected',
   5           'background', 'readonly', 'alternate', 'invalid']
   6
   7 for state in states[:]:
   8     states.append("!" + state)
   9
  10 def reset_state(widget):
  11     nostate = states[len(states) // 2:]
  12     widget.state(nostate)
  13
  14 class App(ttk.Frame):
  15     def __init__(self, title=None):
  16         ttk.Frame.__init__(self, borderwidth=6)
  17         self.master.title(title)
  18
  19         self.style = ttk.Style()
  20
  21         # get default font size and family
  22         btn_font = self.style.lookup("TButton", "font")
  23         fsize = str(self.tk.eval("font configure %s -size" % btn_font))
  24         self.font_family = self.tk.eval("font configure %s -family" % btn_font)
  25         if ' ' in self.font_family:
  26             self.font_family = '{%s}' % self.font_family
  27         self.fsize_prefix = fsize[0] if fsize[0] == '-' else ''
  28         self.base_fsize = int(fsize[1 if fsize[0] == '-' else 0:])
  29
  30         # a list to hold all the widgets that will have their states changed
  31         self.update_widgets = []
  32
  33         self._setup_widgets()
  34
  35     def _set_font(self, extra=0):
  36         self.style.configure("TButton", font="%s %s%d" % (self.font_family,
  37             self.fsize_prefix, self.base_fsize + extra))
  38
  39     def _new_state(self, widget, newtext):
  40         widget = self.nametowidget(widget)
  41
  42         if not newtext:
  43             goodstates = ["disabled"]
  44             font_extra = 0
  45         else:
  46             # set widget state according to what has been entered in the entry
  47             newstates = set(newtext.split()) # eliminate duplicates
  48
  49             # keep only the valid states
  50             goodstates = [state for state in newstates if state in states]
  51             # define a new font size based on amount of states
  52             font_extra = 2 * len(goodstates)
  53
  54         # set new widget state
  55         for widget in self.update_widgets:
  56             reset_state(widget) # remove any previous state from the widget
  57             widget.state(goodstates)
  58
  59         # update Ttk Button font size
  60         self._set_font(font_extra)
  61         return 1
  62
  63     def _setup_widgets(self):
  64         btn = ttk.Button(self, text='Enter states and watch')
  65
  66         entry = ttk.Entry(self, cursor='xterm', validate="key")
  67         entry['validatecommand'] = (self.register(self._new_state), '%W', '%P')
  68         entry.focus()
  69
  70         self.update_widgets.append(btn)
  71         entry.validate()
  72
  73         entry.pack(fill='x', padx=6)
  74         btn.pack(side='left', pady=6, padx=6, anchor='n')
  75         self.pack(fill='both', expand=1)
  76
  77
  78 def main():
  79     app = App("Widget State Tester")
  80     app.mainloop()
  81
  82 if __name__ == "__main__":
  83     main()