1# entry3.rb --
2#
3# This demonstration script creates several entry widgets whose
4# permitted input is constrained in some way.  It also shows off a
5# password entry.
6#
7# based on Tcl/Tk8.4.4 widget demos
8
9if defined?($entry3_demo) && $entry3_demo
10  $entry3_demo.destroy
11  $entry3_demo = nil
12end
13
14$entry3_demo = TkToplevel.new {|w|
15  title("Constrained Entry Demonstration")
16  iconname("entry3")
17  positionWindow(w)
18}
19
20base_frame = TkFrame.new($entry3_demo).pack(:fill=>:both, :expand=>true)
21
22TkLabel.new(base_frame,
23            :font=>$font, :wraplength=>'5i', :justify=>:left,
24            :text=><<EOL).pack(:side=>:top)
25Four different entries are displayed below.  You can add characters \
26by pointing, clicking and typing, though each is constrained in what \
27it will accept.  The first only accepts integers or the empty string \
28(checking when focus leaves it) and will flash to indicate any \
29problem.  The second only accepts strings with fewer than ten \
30characters and sounds the bell when an attempt to go over the limit \
31is made.  The third accepts US phone numbers, mapping letters to \
32their digit equivalent and sounding the bell on encountering an \
33invalid character or if trying to type over a character that is not \
34a digit.  The fourth is a password field that accepts up to eight \
35characters (silently ignoring further ones), and displaying them as \
36asterisk characters.
37EOL
38
39TkFrame.new(base_frame){|f|
40  pack(:side=>:bottom, :fill=>:x, :pady=>'2m')
41
42  TkButton.new(f, :text=>'Dismiss', :width=>15, :command=>proc{
43                 $entry3_demo.destroy
44                 $entry3_demo = nil
45               }).pack(:side=>:left, :expand=>true)
46
47  TkButton.new(f, :text=>'See Code', :width=>15, :command=>proc{
48                 showCode 'entry3'
49               }).pack(:side=>:left, :expand=>true)
50}
51
52# focusAndFlash --
53# Error handler for entry widgets that forces the focus onto the
54# widget and makes the widget flash by exchanging the foreground and
55# background colours at intervals of 200ms (i.e. at approximately
56# 2.5Hz).
57#
58# Arguments:
59# widget -      entry widget to flash
60# fg -          Initial foreground colour
61# bg -          Initial background colour
62# count -       Counter to control the number of times flashed
63def focusAndFlash(widget, fg, bg, count=5)
64  return if count <= 0
65  if fg && !fg.empty? && bg && !bg.empty?
66    TkTimer.new(200, count,
67                proc{widget.configure(:foreground=>bg, :background=>fg)},
68                proc{widget.configure(:foreground=>fg, :background=>bg)}
69                ).start
70  else
71    # TkTimer.new(150, 3){Tk.bell}.start
72    Tk.bell
73    TkTimer.new(200, count,
74                proc{widget.configure(:foreground=>'white',
75                                      :background=>'black')},
76                proc{widget.configure(:foreground=>'black',
77                                      :background=>'white')}
78                ).at_end{begin
79                           widget.configure(:foreground=>fg,
80                                            :background=>bg)
81                         rescue
82                           # ignore
83                         end}.start
84  end
85  widget.focus(true)
86end
87
88l1 = TkLabelFrame.new(base_frame, :text=>"Integer Entry")
89TkEntry.new(l1, :validate=>:focus,
90            :vcmd=>[
91              proc{|s| s == '' || /^[+-]?\d+$/ =~ s }, '%P'
92            ]) {|e|
93  fg = e.foreground
94  bg = e.background
95  invalidcommand [proc{|w| focusAndFlash(w, fg, bg)}, '%W']
96  pack(:fill=>:x, :expand=>true, :padx=>'1m', :pady=>'1m')
97}
98
99l2 = TkLabelFrame.new(base_frame, :text=>"Length-Constrained Entry")
100TkEntry.new(l2, :validate=>:key, :invcmd=>proc{Tk.bell},
101            :vcmd=>[proc{|s| s.length < 10}, '%P']
102            ).pack(:fill=>:x, :expand=>true, :padx=>'1m', :pady=>'1m')
103
104### PHONE NUMBER ENTRY ###
105# Note that the source to this is quite a bit longer as the behaviour
106# demonstrated is a lot more ambitious than with the others.
107
108# Initial content for the third entry widget
109entry3content = TkVariable.new("1-(000)-000-0000")
110
111# Mapping from alphabetic characters to numbers.
112$phoneNumberMap = {}
113Hash[*(%w(abc 2 def 3 ghi 4 jkl 5 mno 6 pqrs 7 tuv 8 wxyz 9))].each{|chars, n|
114  chars.split('').each{|c|
115    $phoneNumberMap[c] = n
116    $phoneNumberMap[c.upcase] = n
117  }
118}
119
120# phoneSkipLeft --
121# Skip over fixed characters in a phone-number string when moving left.
122#
123# Arguments:
124# widget -      The entry widget containing the phone-number.
125def phoneSkipLeft(widget)
126  idx = widget.index('insert')
127  if idx == 8
128    # Skip back two extra characters
129    widget.cursor = idx - 2
130  elsif idx == 7 || idx == 12
131    # Skip back one extra character
132    widget.cursor = idx - 1
133  elsif idx <= 3
134    # Can't move any further
135    Tk.bell
136    Tk.callback_break
137  end
138end
139
140# phoneSkipRight --
141# Skip over fixed characters in a phone-number string when moving right.
142#
143# Arguments:
144# widget -      The entry widget containing the phone-number.
145# add - Offset to add to index before calculation (used by validation.)
146def phoneSkipRight(widget, add = 0)
147  idx = widget.index('insert')
148  if (idx + add == 5)
149    # Skip forward two extra characters
150    widget.cursor = idx + 2
151  elsif (idx + add == 6 || idx + add == 10)
152    # Skip forward one extra character
153    widget.cursor = idx + 1
154  elsif (idx + add == 15 && add == 0)
155    # Can't move any further
156    Tk.bell
157    Tk.callback_break
158  end
159end
160
161# validatePhoneChange --
162# Checks that the replacement (mapped to a digit) of the given
163# character in an entry widget at the given position will leave a
164# valid phone number in the widget.
165#
166# widget - entry widget to validate
167# vmode -  The widget's validation mode
168# idx -    The index where replacement is to occur
169# char -   The character (or string, though that will always be
170#          refused) to be overwritten at that point.
171
172def validatePhoneChange(widget, vmode, idx, char)
173  return true if idx == nil
174  Tk.after_idle(proc{widget.configure(:validate=>vmode,
175                                      :invcmd=>proc{Tk.bell})})
176  if !(idx<3 || idx==6 || idx==7 || idx==11 || idx>15) && char =~ /[0-9A-Za-z]/
177    widget.delete(idx)
178    widget.insert(idx, $phoneNumberMap[char] || char)
179    Tk.after_idle(proc{phoneSkipRight(widget, -1)})
180    return true
181    # Tk.update(true) # <- Don't work 'update' inter validation callback.
182                      #    It depends on Tcl/Tk side (tested on Tcl/Tk8.5a1).
183  end
184  return false
185end
186
187
188l3 = TkLabelFrame.new(base_frame, :text=>"US Phone-Number Entry")
189TkEntry.new(l3, :validate=>:key, :invcmd=>proc{Tk.bell},
190            :textvariable=>entry3content,
191            :vcmd=>[
192              proc{|w,v,i,s| validatePhoneChange(w,v,i,s)},
193              "%W %v %i %S"
194            ]){|e|
195  # Click to focus goes to the first editable character...
196  bind('FocusIn', proc{|d,w|
197         if d != "NotifyAncestor"
198           w.cursor = 3
199           Tk.after_idle(proc{w.selection_clear})
200         end
201       }, '%d %W')
202  bind('Left',  proc{|w| phoneSkipLeft(w)},  '%W')
203  bind('Right', proc{|w| phoneSkipRight(w)}, '%W')
204  pack(:fill=>:x, :expand=>true, :padx=>'1m', :pady=>'1m')
205}
206
207l4 = TkLabelFrame.new(base_frame, :text=>"Password Entry")
208TkEntry.new(l4, :validate=>:key, :show=>'*',
209            :vcmd=>[
210              proc{|s| s.length <= 8},
211              '%P'
212            ]).pack(:fill=>:x, :expand=>true, :padx=>'1m', :pady=>'1m')
213
214TkFrame.new(base_frame){|f|
215  lower
216  TkGrid.configure(l1, l2, :in=>f, :padx=>'3m', :pady=>'1m', :sticky=>:ew)
217  TkGrid.configure(l3, l4, :in=>f, :padx=>'3m', :pady=>'1m', :sticky=>:ew)
218  TkGrid.columnconfigure(f, [0,1], :uniform=>1)
219  pack(:fill=>:both, :expand=>true)
220}
221