/Lib/plat-irix5/panel.py

  1# Module 'panel'
  2#
  3# Support for the Panel library.
  4# Uses built-in module 'pnl'.
  5# Applications should use 'panel.function' instead of 'pnl.function';
  6# most 'pnl' functions are transparently exported by 'panel',
  7# but dopanel() is overridden and you have to use this version
  8# if you want to use callbacks.
  9from warnings import warnpy3k
 10warnpy3k("the panel module has been removed in Python 3.0", stacklevel=2)
 11del warnpy3k
 12
 13
 14import pnl
 15
 16
 17debug = 0
 18
 19
 20# Test if an object is a list.
 21#
 22def is_list(x):
 23    return type(x) == type([])
 24
 25
 26# Reverse a list.
 27#
 28def reverse(list):
 29    res = []
 30    for item in list:
 31        res.insert(0, item)
 32    return res
 33
 34
 35# Get an attribute of a list, which may itself be another list.
 36# Don't use 'prop' for name.
 37#
 38def getattrlist(list, name):
 39    for item in list:
 40        if item and is_list(item) and item[0] == name:
 41            return item[1:]
 42    return []
 43
 44
 45# Get a property of a list, which may itself be another list.
 46#
 47def getproplist(list, name):
 48    for item in list:
 49        if item and is_list(item) and item[0] == 'prop':
 50            if len(item) > 1 and item[1] == name:
 51                return item[2:]
 52    return []
 53
 54
 55# Test if an actuator description contains the property 'end-of-group'
 56#
 57def is_endgroup(list):
 58    x = getproplist(list, 'end-of-group')
 59    return (x and x[0] == '#t')
 60
 61
 62# Neatly display an actuator definition given as S-expression
 63# the prefix string is printed before each line.
 64#
 65def show_actuator(prefix, a):
 66    for item in a:
 67        if not is_list(item):
 68            print prefix, item
 69        elif item and item[0] == 'al':
 70            print prefix, 'Subactuator list:'
 71            for a in item[1:]:
 72                show_actuator(prefix + '    ', a)
 73        elif len(item) == 2:
 74            print prefix, item[0], '=>', item[1]
 75        elif len(item) == 3 and item[0] == 'prop':
 76            print prefix, 'Prop', item[1], '=>',
 77            print item[2]
 78        else:
 79            print prefix, '?', item
 80
 81
 82# Neatly display a panel.
 83#
 84def show_panel(prefix, p):
 85    for item in p:
 86        if not is_list(item):
 87            print prefix, item
 88        elif item and item[0] == 'al':
 89            print prefix, 'Actuator list:'
 90            for a in item[1:]:
 91                show_actuator(prefix + '    ', a)
 92        elif len(item) == 2:
 93            print prefix, item[0], '=>', item[1]
 94        elif len(item) == 3 and item[0] == 'prop':
 95            print prefix, 'Prop', item[1], '=>',
 96            print item[2]
 97        else:
 98            print prefix, '?', item
 99
100
101# Exception raised by build_actuator or build_panel.
102#
103panel_error = 'panel error'
104
105
106# Dummy callback used to initialize the callbacks.
107#
108def dummy_callback(arg):
109    pass
110
111
112# Assign attributes to members of the target.
113# Attribute names in exclist are ignored.
114# The member name is the attribute name prefixed with the prefix.
115#
116def assign_members(target, attrlist, exclist, prefix):
117    for item in attrlist:
118        if is_list(item) and len(item) == 2 and item[0] not in exclist:
119            name, value = item[0], item[1]
120            ok = 1
121            if value[0] in '-0123456789':
122                value = eval(value)
123            elif value[0] == '"':
124                value = value[1:-1]
125            elif value == 'move-then-resize':
126                # Strange default set by Panel Editor...
127                ok = 0
128            else:
129                print 'unknown value', value, 'for', name
130                ok = 0
131            if ok:
132                lhs = 'target.' + prefix + name
133                stmt = lhs + '=' + repr(value)
134                if debug: print 'exec', stmt
135                try:
136                    exec stmt + '\n'
137                except KeyboardInterrupt: # Don't catch this!
138                    raise KeyboardInterrupt
139                except:
140                    print 'assign failed:', stmt
141
142
143# Build a real actuator from an actuator description.
144# Return a pair (actuator, name).
145#
146def build_actuator(descr):
147    namelist = getattrlist(descr, 'name')
148    if namelist:
149        # Assume it is a string
150        actuatorname = namelist[0][1:-1]
151    else:
152        actuatorname = ''
153    type = descr[0]
154    if type[:4] == 'pnl_': type = type[4:]
155    act = pnl.mkact(type)
156    act.downfunc = act.activefunc = act.upfunc = dummy_callback
157    #
158    assign_members(act, descr[1:], ['al', 'data', 'name'], '')
159    #
160    # Treat actuator-specific data
161    #
162    datalist = getattrlist(descr, 'data')
163    prefix = ''
164    if type[-4:] == 'puck':
165        prefix = 'puck_'
166    elif type == 'mouse':
167        prefix = 'mouse_'
168    assign_members(act, datalist, [], prefix)
169    #
170    return act, actuatorname
171
172
173# Build all sub-actuators and add them to the super-actuator.
174# The super-actuator must already have been added to the panel.
175# Sub-actuators with defined names are added as members to the panel
176# so they can be referenced as p.name.
177#
178# Note: I have no idea how panel.endgroup() works when applied
179# to a sub-actuator.
180#
181def build_subactuators(panel, super_act, al):
182    #
183    # This is nearly the same loop as below in build_panel(),
184    # except a call is made to addsubact() instead of addact().
185    #
186    for a in al:
187        act, name = build_actuator(a)
188        act.addsubact(super_act)
189        if name:
190            stmt = 'panel.' + name + ' = act'
191            if debug: print 'exec', stmt
192            exec stmt + '\n'
193        if is_endgroup(a):
194            panel.endgroup()
195        sub_al = getattrlist(a, 'al')
196        if sub_al:
197            build_subactuators(panel, act, sub_al)
198    #
199    # Fix the actuator to which whe just added subactuators.
200    # This can't hurt (I hope) and is needed for the scroll actuator.
201    #
202    super_act.fixact()
203
204
205# Build a real panel from a panel definition.
206# Return a panel object p, where for each named actuator a, p.name is a
207# reference to a.
208#
209def build_panel(descr):
210    #
211    # Sanity check
212    #
213    if (not descr) or descr[0] != 'panel':
214        raise panel_error, 'panel description must start with "panel"'
215    #
216    if debug: show_panel('', descr)
217    #
218    # Create an empty panel
219    #
220    panel = pnl.mkpanel()
221    #
222    # Assign panel attributes
223    #
224    assign_members(panel, descr[1:], ['al'], '')
225    #
226    # Look for actuator list
227    #
228    al = getattrlist(descr, 'al')
229    #
230    # The order in which actuators are created is important
231    # because of the endgroup() operator.
232    # Unfortunately the Panel Editor outputs the actuator list
233    # in reverse order, so we reverse it here.
234    #
235    al = reverse(al)
236    #
237    for a in al:
238        act, name = build_actuator(a)
239        act.addact(panel)
240        if name:
241            stmt = 'panel.' + name + ' = act'
242            exec stmt + '\n'
243        if is_endgroup(a):
244            panel.endgroup()
245        sub_al = getattrlist(a, 'al')
246        if sub_al:
247            build_subactuators(panel, act, sub_al)
248    #
249    return panel
250
251
252# Wrapper around pnl.dopanel() which calls call-back functions.
253#
254def my_dopanel():
255    # Extract only the first 4 elements to allow for future expansion
256    a, down, active, up = pnl.dopanel()[:4]
257    if down:
258        down.downfunc(down)
259    if active:
260        active.activefunc(active)
261    if up:
262        up.upfunc(up)
263    return a
264
265
266# Create one or more panels from a description file (S-expressions)
267# generated by the Panel Editor.
268#
269def defpanellist(file):
270    import panelparser
271    descrlist = panelparser.parse_file(open(file, 'r'))
272    panellist = []
273    for descr in descrlist:
274        panellist.append(build_panel(descr))
275    return panellist
276
277
278# Import everything from built-in method pnl, so the user can always
279# use panel.foo() instead of pnl.foo().
280# This gives *no* performance penalty once this module is imported.
281#
282from pnl import *                       # for export
283
284dopanel = my_dopanel                    # override pnl.dopanel