# This module is used by the Pmw package system.
# The PmwLoader class can be used to simulate a python module,
# but also supports importing of submodules on demand. This technique
# reduces startup time because Pmw submodules which are not used are
# not loaded.
#
# The PmwLoader class also supports runtime selection of the Pmw
# version(s) to use.
import sys
import os
import string
import types
_PMW_DEF = 'Pmw.def' # Pmw definition file
_BASEMODULE = 'Base' # Name of Base module
class PmwLoader:
def __init__(self, dirpath, instdirs, dirs):
self._dirpath = dirpath
self._instdirs = instdirs
self._dirs = dirs
self._initialised = 0
self._version = string.replace(instdirs[0][4:], '_', '.')
self._alpha_versions = ()
#======================================================================
# Public methods. These methods will be seen as "module methods".
def setversion(self, version):
if self._version == version:
return
if self._initialised:
raise ValueError, 'Cannot change Pmw version after initialisation'
self._version = version
def setalphaversions(self, *alpha_versions):
if self._alpha_versions == alpha_versions:
return
if self._initialised:
raise ValueError, \
'Cannot change Pmw alpha versions after initialisation'
self._alpha_versions = alpha_versions
def version(self, alpha = 0):
if alpha:
return self._alpha_versions
else:
return self._version
def installedversions(self, alpha = 0):
rtn = []
if alpha:
dirs = filter(lambda x: x[:5] == 'Alpha', self._dirs)
dirs.sort()
dirs.reverse()
for dir in dirs:
rtn.append(string.replace(dir[6:], '_', '.'))
else:
for dir in self._instdirs:
rtn.append(string.replace(dir[4:], '_', '.'))
return rtn
#======================================================================
# Private methods
def _getmodule(self,modpath):
__import__(modpath)
mod = sys.modules[modpath]
return mod
def _initialise(self):
searchpath = []
for version in self._alpha_versions:
alphadir = '_Pmw.Alpha_%s.lib' % string.replace(version, '.', '_')
searchpath.append(alphadir)
libdir = '_Pmw.Pmw_%s.lib' % string.replace(self._version, '.', '_')
searchpath.append(libdir)
# Create attributes for the PmwBase classes and functions.
for path in searchpath:
try:
basemodule = self._getmodule(path + '.Pmw' + _BASEMODULE)
break
except ImportError, msg:
if path == searchpath[-1]:
# No PmwBase module found.
raise ImportError, msg
for k,v in basemodule.__dict__.items():
if k[0] is not '_' and type(v) != types.ModuleType:
self.__dict__[k] = v
# Set the Pmw definitions from the Pmw.def file.
dict = {
'_widgets' : {},
'_extraWidgets' : {},
'_functions' : {},
'_modules' : {},
}
for name in dict.keys():
self.__dict__[name] = {}
searchpath.reverse()
for path in searchpath:
pathbit = apply(os.path.join, tuple(string.split(path[5:], '.')))
lpath = os.path.join(self._dirpath, pathbit)
d = {}
execfile(os.path.join(lpath,_PMW_DEF), d)
for k,v in d.items():
if dict.has_key(k):
if type(v) == types.TupleType:
for item in v:
modpath = path + '.Pmw' + item
dict[k][item] = modpath
elif type(v) == types.DictionaryType:
for k1, v1 in v.items():
modpath = path + '.Pmw' + v1
dict[k][k1] = modpath
self.__dict__.update(dict)
self._widgets_keys = self._widgets.keys()
self._extraWidgets_keys = self._extraWidgets.keys()
self._functions_keys = self._functions.keys()
self._modules_keys = self._modules.keys()
self._initialised = 1
def __getattr__(self, name):
if not self._initialised:
self._initialise()
# Beware: _initialise may have defined 'name'
if name in self.__dict__.keys():
return self.__dict__[name]
# The requested attribute is not yet set. Look it up in the
# tables set by Pmw.def, import the appropriate module and
# set the attribute so that it will be found next time.
if name in self._widgets_keys:
# The attribute is a widget name.
mod = self._getmodule(self._widgets[name])
cls = getattr(mod,name)
self.__dict__[name] = cls
return cls
if name in self._functions_keys:
# The attribute is a function from one of the modules.
modname = self._functions[name]
mod = self._getmodule(modname)
func = getattr(mod, name)
self.__dict__[name] = func
return func
if name in self._modules_keys:
# The attribute is a module
mod = self._getmodule(self._modules[name])
self.__dict__[name] = mod
return mod
if name in self._extraWidgets_keys:
# XXX I should import them all, once I've started.
# The attribute is a widget name in a module of another name
modname = self._extraWidgets[name]
mod = self._getmodule(modname)
cls = getattr(mod, name)
self.__dict__[name] = cls
return cls
# The attribute is not known by Pmw, report an error.
raise AttributeError, name
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