# Module 'panel'
#
# Support for the Panel library.
# Uses built-in module 'pnl'.
# Applciations should use 'panel.function' instead of 'pnl.function';
# most 'pnl' functions are transparently exported by 'panel',
# but dopanel() is overridden and you have to use this version
# if you want to use callbacks.
import pnl
debug = 0
# Test if an object is a list.
#
def is_list(x):
return type(x) == type([])
# Reverse a list.
#
def reverse(list):
res = []
for item in list:
res.insert(0, item)
return res
# Get an attribute of a list, which may itself be another list.
# Don't use 'prop' for name.
#
def getattrlist(list, name):
for item in list:
if item and is_list(item) and item[0] == name:
return item[1:]
return []
# Get a property of a list, which may itself be another list.
#
def getproplist(list, name):
for item in list:
if item and is_list(item) and item[0] == 'prop':
if len(item) > 1 and item[1] == name:
return item[2:]
return []
# Test if an actuator description contains the property 'end-of-group'
#
def is_endgroup(list):
x = getproplist(list, 'end-of-group')
return (x and x[0] == '#t')
# Neatly display an actuator definition given as S-expression
# the prefix string is printed before each line.
#
def show_actuator(prefix, a):
for item in a:
if not is_list(item):
print prefix, item
elif item and item[0] == 'al':
print prefix, 'Subactuator list:'
for a in item[1:]:
show_actuator(prefix + ' ', a)
elif len(item) == 2:
print prefix, item[0], '=>', item[1]
elif len(item) == 3 and item[0] == 'prop':
print prefix, 'Prop', item[1], '=>',
print item[2]
else:
print prefix, '?', item
# Neatly display a panel.
#
def show_panel(prefix, p):
for item in p:
if not is_list(item):
print prefix, item
elif item and item[0] == 'al':
print prefix, 'Actuator list:'
for a in item[1:]:
show_actuator(prefix + ' ', a)
elif len(item) == 2:
print prefix, item[0], '=>', item[1]
elif len(item) == 3 and item[0] == 'prop':
print prefix, 'Prop', item[1], '=>',
print item[2]
else:
print prefix, '?', item
# Exception raised by build_actuator or build_panel.
#
panel_error = 'panel error'
# Dummy callback used to initialize the callbacks.
#
def dummy_callback(arg):
pass
# Assign attributes to members of the target.
# Attribute names in exclist are ignored.
# The member name is the attribute name prefixed with the prefix.
#
def assign_members(target, attrlist, exclist, prefix):
for item in attrlist:
if is_list(item) and len(item) == 2 and item[0] not in exclist:
name, value = item[0], item[1]
ok = 1
if value[0] in '-0123456789':
value = eval(value)
elif value[0] == '"':
value = value[1:-1]
elif value == 'move-then-resize':
# Strange default set by Panel Editor...
ok = 0
else:
print 'unknown value', value, 'for', name
ok = 0
if ok:
lhs = 'target.' + prefix + name
stmt = lhs + '=' + `value`
if debug: print 'exec', stmt
try:
exec stmt + '\n'
except KeyboardInterrupt: # Don't catch this!
raise KeyboardInterrupt
except:
print 'assign failed:', stmt
# Build a real actuator from an actuator descriptior.
# Return a pair (actuator, name).
#
def build_actuator(descr):
namelist = getattrlist(descr, 'name')
if namelist:
# Assume it is a string
actuatorname = namelist[0][1:-1]
else:
actuatorname = ''
type = descr[0]
if type[:4] == 'pnl_': type = type[4:]
act = pnl.mkact(type)
act.downfunc = act.activefunc = act.upfunc = dummy_callback
#
assign_members(act, descr[1:], ['al', 'data', 'name'], '')
#
# Treat actuator-specific data
#
datalist = getattrlist(descr, 'data')
prefix = ''
if type[-4:] == 'puck':
prefix = 'puck_'
elif type == 'mouse':
prefix = 'mouse_'
assign_members(act, datalist, [], prefix)
#
return act, actuatorname
# Build all sub-actuators and add them to the super-actuator.
# The super-actuator must already have been added to the panel.
# Sub-actuators with defined names are added as members to the panel
# so they can be referenced as p.name.
#
# Note: I have no idea how panel.endgroup() works when applied
# to a sub-actuator.
#
def build_subactuators(panel, super_act, al):
#
# This is nearly the same loop as below in build_panel(),
# except a call is made to addsubact() instead of addact().
#
for a in al:
act, name = build_actuator(a)
act.addsubact(super_act)
if name:
stmt = 'panel.' + name + ' = act'
if debug: print 'exec', stmt
exec stmt + '\n'
if is_endgroup(a):
panel.endgroup()
sub_al = getattrlist(a, 'al')
if sub_al:
build_subactuators(panel, act, sub_al)
#
# Fix the actuator to which whe just added subactuators.
# This can't hurt (I hope) and is needed for the scroll actuator.
#
super_act.fixact()
# Build a real panel from a panel definition.
# Return a panel object p, where for each named actuator a, p.name is a
# reference to a.
#
def build_panel(descr):
#
# Sanity check
#
if (not descr) or descr[0] <> 'panel':
raise panel_error, 'panel description must start with "panel"'
#
if debug: show_panel('', descr)
#
# Create an empty panel
#
panel = pnl.mkpanel()
#
# Assign panel attributes
#
assign_members(panel, descr[1:], ['al'], '')
#
# Look for actuator list
#
al = getattrlist(descr, 'al')
#
# The order in which actuators are created is important
# because of the endgroup() operator.
# Unfortunately the Panel Editor outputs the actuator list
# in reverse order, so we reverse it here.
#
al = reverse(al)
#
for a in al:
act, name = build_actuator(a)
act.addact(panel)
if name:
stmt = 'panel.' + name + ' = act'
exec stmt + '\n'
if is_endgroup(a):
panel.endgroup()
sub_al = getattrlist(a, 'al')
if sub_al:
build_subactuators(panel, act, sub_al)
#
return panel
# Wrapper around pnl.dopanel() which calls call-back functions.
#
def my_dopanel():
# Extract only the first 4 elements to allow for future expansion
a, down, active, up = pnl.dopanel()[:4]
if down:
down.downfunc(down)
if active:
active.activefunc(active)
if up:
up.upfunc(up)
return a
# Create one or more panels from a description file (S-expressions)
# generated by the Panel Editor.
#
def defpanellist(file):
import panelparser
descrlist = panelparser.parse_file(open(file, 'r'))
panellist = []
for descr in descrlist:
panellist.append(build_panel(descr))
return panellist
# Import everything from built-in method pnl, so the user can always
# use panel.foo() instead of pnl.foo().
# This gives *no* performance penalty once this module is imported.
#
from pnl import *# for export
dopanel = my_dopanel # override pnl.dopanel
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