1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
|
# entry3.rb --
#
# This demonstration script creates several entry widgets whose
# permitted input is constrained in some way. It also shows off a
# password entry.
#
# based on Tcl/Tk8.4.4 widget demos
if defined?($entry3_demo) && $entry3_demo
$entry3_demo.destroy
$entry3_demo = nil
end
$entry3_demo = TkToplevel.new {|w|
title("Constrained Entry Demonstration")
iconname("entry3")
positionWindow(w)
}
base_frame = TkFrame.new($entry3_demo).pack(:fill=>:both, :expand=>true)
TkLabel.new(base_frame,
:font=>$font, :wraplength=>'5i', :justify=>:left,
:text=><<EOL).pack(:side=>:top)
Four different entries are displayed below. You can add characters \
by pointing, clicking and typing, though each is constrained in what \
it will accept. The first only accepts integers or the empty string \
(checking when focus leaves it) and will flash to indicate any \
problem. The second only accepts strings with fewer than ten \
characters and sounds the bell when an attempt to go over the limit \
is made. The third accepts US phone numbers, mapping letters to \
their digit equivalent and sounding the bell on encountering an \
invalid character or if trying to type over a character that is not \
a digit. The fourth is a password field that accepts up to eight \
characters (silently ignoring further ones), and displaying them as \
asterisk characters.
EOL
TkFrame.new(base_frame){|f|
pack(:side=>:bottom, :fill=>:x, :pady=>'2m')
TkButton.new(f, :text=>'Dismiss', :width=>15, :command=>proc{
$entry3_demo.destroy
$entry3_demo = nil
}).pack(:side=>:left, :expand=>true)
TkButton.new(f, :text=>'See Code', :width=>15, :command=>proc{
showCode 'entry3'
}).pack(:side=>:left, :expand=>true)
}
# focusAndFlash --
# Error handler for entry widgets that forces the focus onto the
# widget and makes the widget flash by exchanging the foreground and
# background colours at intervals of 200ms (i.e. at approximately
# 2.5Hz).
#
# Arguments:
# widget - entry widget to flash
# fg - Initial foreground colour
# bg - Initial background colour
# count - Counter to control the number of times flashed
def focusAndFlash(widget, fg, bg, count=5)
return if count <= 0
if fg && !fg.empty? && bg && !bg.empty?
TkTimer.new(200, count,
proc{widget.configure(:foreground=>bg, :background=>fg)},
proc{widget.configure(:foreground=>fg, :background=>bg)}
).start
else
# TkTimer.new(150, 3){Tk.bell}.start
Tk.bell
TkTimer.new(200, count,
proc{widget.configure(:foreground=>'white',
:background=>'black')},
proc{widget.configure(:foreground=>'black',
:background=>'white')}
).at_end{begin
widget.configure(:foreground=>fg,
:background=>bg)
rescue
# ignore
end}.start
end
widget.focus(true)
end
l1 = TkLabelFrame.new(base_frame, :text=>"Integer Entry")
TkEntry.new(l1, :validate=>:focus,
:vcmd=>[
proc{|s| s == '' || /^[+-]?\d+$/ =~ s }, '%P'
]) {|e|
fg = e.foreground
bg = e.background
invalidcommand [proc{|w| focusAndFlash(w, fg, bg)}, '%W']
pack(:fill=>:x, :expand=>true, :padx=>'1m', :pady=>'1m')
}
l2 = TkLabelFrame.new(base_frame, :text=>"Length-Constrained Entry")
TkEntry.new(l2, :validate=>:key, :invcmd=>proc{Tk.bell},
:vcmd=>[proc{|s| s.length < 10}, '%P']
).pack(:fill=>:x, :expand=>true, :padx=>'1m', :pady=>'1m')
### PHONE NUMBER ENTRY ###
# Note that the source to this is quite a bit longer as the behaviour
# demonstrated is a lot more ambitious than with the others.
# Initial content for the third entry widget
entry3content = TkVariable.new("1-(000)-000-0000")
# Mapping from alphabetic characters to numbers.
$phoneNumberMap = {}
Hash[*(%w(abc 2 def 3 ghi 4 jkl 5 mno 6 pqrs 7 tuv 8 wxyz 9))].each{|chars, n|
chars.split('').each{|c|
$phoneNumberMap[c] = n
$phoneNumberMap[c.upcase] = n
}
}
# phoneSkipLeft --
# Skip over fixed characters in a phone-number string when moving left.
#
# Arguments:
# widget - The entry widget containing the phone-number.
def phoneSkipLeft(widget)
idx = widget.index('insert')
if idx == 8
# Skip back two extra characters
widget.cursor = idx - 2
elsif idx == 7 || idx == 12
# Skip back one extra character
widget.cursor = idx - 1
elsif idx <= 3
# Can't move any further
Tk.bell
Tk.callback_break
end
end
# phoneSkipRight --
# Skip over fixed characters in a phone-number string when moving right.
#
# Arguments:
# widget - The entry widget containing the phone-number.
# add - Offset to add to index before calculation (used by validation.)
def phoneSkipRight(widget, add = 0)
idx = widget.index('insert')
if (idx + add == 5)
# Skip forward two extra characters
widget.cursor = idx + 2
elsif (idx + add == 6 || idx + add == 10)
# Skip forward one extra character
widget.cursor = idx + 1
elsif (idx + add == 15 && add == 0)
# Can't move any further
Tk.bell
Tk.callback_break
end
end
# validatePhoneChange --
# Checks that the replacement (mapped to a digit) of the given
# character in an entry widget at the given position will leave a
# valid phone number in the widget.
#
# widget - entry widget to validate
# vmode - The widget's validation mode
# idx - The index where replacement is to occur
# char - The character (or string, though that will always be
# refused) to be overwritten at that point.
def validatePhoneChange(widget, vmode, idx, char)
return true if idx == nil
Tk.after_idle(proc{widget.configure(:validate=>vmode,
:invcmd=>proc{Tk.bell})})
if !(idx<3 || idx==6 || idx==7 || idx==11 || idx>15) && char =~ /[0-9A-Za-z]/
widget.delete(idx)
widget.insert(idx, $phoneNumberMap[char] || char)
Tk.after_idle(proc{phoneSkipRight(widget, -1)})
return true
# Tk.update(true) # <- Don't work 'update' inter validation callback.
# It depends on Tcl/Tk side (tested on Tcl/Tk8.5a1).
end
return false
end
l3 = TkLabelFrame.new(base_frame, :text=>"US Phone-Number Entry")
TkEntry.new(l3, :validate=>:key, :invcmd=>proc{Tk.bell},
:textvariable=>entry3content,
:vcmd=>[
proc{|w,v,i,s| validatePhoneChange(w,v,i,s)},
"%W %v %i %S"
]){|e|
# Click to focus goes to the first editable character...
bind('FocusIn', proc{|d,w|
if d != "NotifyAncestor"
w.cursor = 3
Tk.after_idle(proc{w.selection_clear})
end
}, '%d %W')
bind('Left', proc{|w| phoneSkipLeft(w)}, '%W')
bind('Right', proc{|w| phoneSkipRight(w)}, '%W')
pack(:fill=>:x, :expand=>true, :padx=>'1m', :pady=>'1m')
}
l4 = TkLabelFrame.new(base_frame, :text=>"Password Entry")
TkEntry.new(l4, :validate=>:key, :show=>'*',
:vcmd=>[
proc{|s| s.length <= 8},
'%P'
]).pack(:fill=>:x, :expand=>true, :padx=>'1m', :pady=>'1m')
TkFrame.new(base_frame){|f|
lower
TkGrid.configure(l1, l2, :in=>f, :padx=>'3m', :pady=>'1m', :sticky=>:ew)
TkGrid.configure(l3, l4, :in=>f, :padx=>'3m', :pady=>'1m', :sticky=>:ew)
TkGrid.columnconfigure(f, [0,1], :uniform=>1)
pack(:fill=>:both, :expand=>true)
}
|
