wizard/BModulePage.py

   1 #!/usr/bin/env python
   2 # encoding: utf-8
   3 #
   4 # This file is part of BeRTOS.
   5 #
   6 # Bertos is free software; you can redistribute it and/or modify
   7 # it under the terms of the GNU General Public License as published by
   8 # the Free Software Foundation; either version 2 of the License, or
   9 # (at your option) any later version.
  10 #
  11 # This program is distributed in the hope that it will be useful,
  12 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 # GNU General Public License for more details.
  15 #
  16 # You should have received a copy of the GNU General Public License
  17 # along with this program; if not, write to the Free Software
  18 # Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  19 #
  20 # As a special exception, you may use this file as part of a free software
  21 # library without restriction.  Specifically, if other files instantiate
  22 # templates or use macros or inline functions from this file, or you compile
  23 # this file and link it with other files to produce an executable, this
  24 # file does not by itself cause the resulting executable to be covered by
  25 # the GNU General Public License.  This exception does not however
  26 # invalidate any other reasons why the executable file might be covered by
  27 # the GNU General Public License.
  28 #
  29 # Copyright 2008 Develer S.r.l. (http://www.develer.com/)
  30 #
  31 # $Id$
  32 #
  33 # Author: Lorenzo Berni <duplo@develer.com>
  34 #
  35
  36 import os
  37
  38 from PyQt4.QtCore import *
  39 from PyQt4.QtGui import *
  40 from BWizardPage import *
  41 import bertos_utils
  42
  43 from bertos_utils import SupportedException
  44 from DefineException import *
  45 from const import *
  46
  47 class BModulePage(BWizardPage):
  48     """
  49     Page of the wizard that permits to select and configurate the BeRTOS modules.
  50     """
  51
  52     def __init__(self):
  53         BWizardPage.__init__(self, UI_LOCATION + "/module_select.ui")
  54         self.setTitle(self.tr("Configure the BeRTOS modules"))
  55         self._control_group = QControlGroup()
  56         ## special connection needed for the QControlGroup
  57         self.connect(self._control_group, SIGNAL("stateChanged"), self.saveValue)
  58
  59     ## Overloaded BWizardPage methods ##
  60
  61     def setupUi(self):
  62         """
  63         Overload of BWizardPage setupUi method.
  64         """
  65         self.pageContent.moduleTree.clear()
  66         self.pageContent.moduleTree.setHeaderHidden(True)
  67         self.pageContent.propertyTable.horizontalHeader().setResizeMode(QHeaderView.Stretch)
  68         self.pageContent.propertyTable.horizontalHeader().setVisible(False)
  69         self.pageContent.propertyTable.verticalHeader().setResizeMode(QHeaderView.ResizeToContents)
  70         self.pageContent.propertyTable.verticalHeader().setVisible(False)
  71         self.pageContent.propertyTable.setColumnCount(2)
  72         self.pageContent.propertyTable.setRowCount(0)
  73         self.pageContent.moduleLabel.setVisible(False)
  74         self.pageContent.warningLabel.setVisible(False)
  75
  76     def connectSignals(self):
  77         """
  78         Overload of the BWizardPage connectSignals method.
  79         """
  80         self.connect(self.pageContent.moduleTree, SIGNAL("itemPressed(QTreeWidgetItem*, int)"), self.fillPropertyTable)
  81         self.connect(self.pageContent.moduleTree, SIGNAL("itemPressed(QTreeWidgetItem*, int)"), self.moduleClicked)
  82         self.connect(self.pageContent.moduleTree, SIGNAL("itemChanged(QTreeWidgetItem*, int)"), self.dependencyCheck)
  83         self.connect(self.pageContent.propertyTable, SIGNAL("itemSelectionChanged()"), self.showPropertyDescription)
  84
  85     def reloadData(self):
  86         """
  87         Overload of the BWizardPage reloadData method.
  88         """
  89         try:
  90             QApplication.instance().setOverrideCursor(Qt.WaitCursor)
  91             self.setupUi()
  92             self.loadModuleData()
  93             self.fillModuleTree()
  94         finally:
  95             QApplication.instance().restoreOverrideCursor()
  96
  97     ####
  98
  99     ## Slots ##
 100
 101     def moduleClicked(self, item, column):
 102         self.setBold(item, False)
 103
 104     def fillPropertyTable(self):
 105         """
 106         Slot called when the user selects a module from the module tree.
 107         Fills the property table using the configuration parameters defined in
 108         the source tree.
 109         """
 110         module = self.currentModule()
 111         if module:
 112             try:
 113                 supported = bertos_utils.isSupported(self.project, module=module)
 114             except SupportedException, e:
 115                 self.exceptionOccurred(self.tr("Error evaluating \"%1\" for module %2").arg(e.support_string).arg(module))
 116                 supported = True
 117             self._control_group.clear()
 118             configuration = self.projectInfo("MODULES")[module]["configuration"]
 119             module_description = self.projectInfo("MODULES")[module]["description"]
 120             self.pageContent.moduleLabel.setText(module_description)
 121             self.pageContent.moduleLabel.setVisible(True)
 122             if not supported:
 123                 self.pageContent.warningLabel.setVisible(True)
 124                 selected_cpu = self.projectInfo("CPU_NAME")
 125                 self.pageContent.warningLabel.setText(self.tr("<font color='#FF0000'>Warning: the selected module, \
 126                     is not completely supported by the %1.</font>").arg(selected_cpu))
 127             else:
 128                 self.pageContent.warningLabel.setVisible(False)
 129             self.pageContent.propertyTable.clear()
 130             self.pageContent.propertyTable.setRowCount(0)
 131             if configuration != "":
 132                 configurations = self.projectInfo("CONFIGURATIONS")[configuration]
 133                 param_list = sorted(configurations["paramlist"])
 134                 index = 0
 135                 for i, property in param_list:
 136                     if "type" in configurations[property]["informations"] and configurations[property]["informations"]["type"] == "autoenabled":
 137                         # Doesn't show the hidden fields
 138                         continue
 139                     try:
 140                         param_supported = bertos_utils.isSupported(self.project, property_id=(configuration, property))
 141                     except SupportedException, e:
 142                         self.exceptionOccurred(self.tr("Error evaluating \"%1\" for parameter %2").arg(e.support_string).arg(property))
 143                         param_supported = True
 144                     if not param_supported:
 145                         # Doesn't show the unsupported parameters
 146                         continue
 147                     # Set the row count to the current index + 1
 148                     self.pageContent.propertyTable.setRowCount(index + 1)
 149                     item = QTableWidgetItem(configurations[property]["brief"])
 150                     item.setData(Qt.UserRole, qvariant_converter.convertString(property))
 151                     self.pageContent.propertyTable.setItem(index, 0, item)
 152                     if "type" in configurations[property]["informations"] and configurations[property]["informations"]["type"] == "boolean":
 153                         self.insertCheckBox(index, configurations[property]["value"])
 154                     elif "type" in configurations[property]["informations"] and configurations[property]["informations"]["type"] == "enum":
 155                         self.insertComboBox(index, configurations[property]["value"], configurations[property]["informations"]["value_list"])
 156                     elif "type" in configurations[property]["informations"] and configurations[property]["informations"]["type"] == "int":
 157                         self.insertSpinBox(index, configurations[property]["value"], configurations[property]["informations"])
 158                     else:
 159                         # Not defined type, rendered as a text field
 160                         self.pageContent.propertyTable.setItem(index, 1, QTableWidgetItem(configurations[property]["value"]))
 161                     index += 1
 162             if self.pageContent.propertyTable.rowCount() == 0:
 163                 module_label = self.pageContent.moduleLabel.text()
 164                 module_label += "\n\nNo configuration needed."
 165                 self.pageContent.moduleLabel.setText(module_label)
 166         else:
 167             self.pageContent.moduleLabel.setText("")
 168             self.pageContent.moduleLabel.setVisible(False)
 169             self.pageContent.propertyTable.clear()
 170             self.pageContent.propertyTable.setRowCount(0)
 171
 172     def dependencyCheck(self, item):
 173         """
 174         Checks the dependencies of the module associated with the given item.
 175         """
 176         checked = False
 177         module = unicode(item.text(0))
 178         if item.checkState(0) == Qt.Checked:
 179             self.moduleSelected(module)
 180         else:
 181             self.moduleUnselected(module)
 182             self.removeFileDependencies(module)
 183
 184     def showPropertyDescription(self):
 185         """
 186         Slot called when the property selection changes. Shows the description
 187         of the selected property.
 188         """
 189         self.resetPropertyDescription()
 190         configurations = self.currentModuleConfigurations()
 191         if self.currentProperty() in configurations:
 192             description = configurations[self.currentProperty()]["brief"]
 193             name = self.currentProperty()
 194             self.currentPropertyItem().setText(description + "\n" + name)
 195
 196     def saveValue(self, index):
 197         """
 198         Slot called when the user modifies one of the configuration parameters.
 199         It stores the new value."""
 200         property = qvariant_converter.getString(self.pageContent.propertyTable.item(index, 0).data(Qt.UserRole))
 201         configuration = self.projectInfo("MODULES")[self.currentModule()]["configuration"]
 202         configurations = self.projectInfo("CONFIGURATIONS")
 203         if "type" not in configurations[configuration][property]["informations"] or configurations[configuration][property]["informations"]["type"] == "int":
 204             configurations[configuration][property]["value"] = unicode(int(self.pageContent.propertyTable.cellWidget(index, 1).value()))
 205         elif configurations[configuration][property]["informations"]["type"] == "enum":
 206             configurations[configuration][property]["value"] = unicode(self.pageContent.propertyTable.cellWidget(index, 1).currentText())
 207         elif configurations[configuration][property]["informations"]["type"] == "boolean":
 208             if self.pageContent.propertyTable.cellWidget(index, 1).isChecked():
 209                 configurations[configuration][property]["value"] = "1"
 210             else:
 211                 configurations[configuration][property]["value"] = "0"
 212         self.setProjectInfo("CONFIGURATIONS", configurations)
 213         if self.moduleItem(self.currentModule()).checkState(0) == Qt.Checked:
 214             self.dependencyCheck(self.moduleItem(self.currentModule()))
 215
 216     ####
 217
 218     def loadModuleData(self):
 219         """
 220         Loads the module data.
 221         """
 222         # Do not load the module data again when the Wizard is in editing mode
 223         # or when it's working on a preset.
 224         if not self.project.edit and not self.project.from_preset:
 225             # Load the module data every time so that if the user changed the cpu
 226             # the right configurations are picked up.
 227             try:
 228                 self.project.loadModuleData()
 229             except ModuleDefineException, e:
 230                 self.exceptionOccurred(self.tr("Error parsing line '%2' in file %1").arg(e.path).arg(e.line))
 231             except EnumDefineException, e:
 232                 self.exceptionOccurred(self.tr("Error parsing line '%2' in file %1").arg(e.path).arg(e.line))
 233             except ConfigurationDefineException, e:
 234                 self.exceptionOccurred(self.tr("Error parsing line '%2' in file %1").arg(e.path).arg(e.line))
 235
 236     def fillModuleTree(self):
 237         """
 238         Fills the module tree with the module entries separated in categories.
 239         """
 240         self.pageContent.moduleTree.clear()
 241         modules = self.projectInfo("MODULES")
 242         if not modules:
 243             return
 244         categories = {}
 245         for module, information in modules.items():
 246             if information["category"] not in categories:
 247                 categories[information["category"]] = []
 248             categories[information["category"]].append(module)
 249         for category, module_list in categories.items():
 250             item = QTreeWidgetItem(QStringList([category]))
 251             for module in module_list:
 252                 enabled = modules[module]["enabled"]
 253                 module_item = QTreeWidgetItem(item, QStringList([module]))
 254                 try:
 255                     supported = bertos_utils.isSupported(self.project, module=module)
 256                 except SupportedException, e:
 257                     self.exceptionOccurred(self.tr("Error evaluating \"%1\" for module %2").arg(e.support_string).arg(module))
 258                     supported = True
 259                 if not supported:
 260                     module_item.setForeground(0, QBrush(QColor(Qt.red)))
 261                 if enabled:
 262                     module_item.setCheckState(0, Qt.Checked)
 263                 else:
 264                     module_item.setCheckState(0, Qt.Unchecked)
 265             self.pageContent.moduleTree.addTopLevelItem(item)
 266         self.pageContent.moduleTree.sortItems(0, Qt.AscendingOrder)
 267         self.fillPropertyTable()
 268
 269     def insertCheckBox(self, index, value):
 270         """
 271         Inserts in the table at index a checkbox for a boolean property setted
 272         to value.
 273         """
 274         check_box = QCheckBox()
 275         self.pageContent.propertyTable.setCellWidget(index, 1, check_box)
 276         if value == "1":
 277             check_box.setChecked(True)
 278         else:
 279             check_box.setChecked(False)
 280         self._control_group.addControl(index, check_box)
 281
 282     def insertComboBox(self, index, value, value_list):
 283         """
 284         Inserts in the table at index a combobox for an enum property setted
 285         to value.
 286         """
 287         try:
 288             enum = self.projectInfo("LISTS")[value_list]
 289             combo_box = QComboBox()
 290             self.pageContent.propertyTable.setCellWidget(index, 1, combo_box)
 291             for i, element in enumerate(enum):
 292                 combo_box.addItem(element)
 293                 if element == value:
 294                     combo_box.setCurrentIndex(i)
 295             self._control_group.addControl(index, combo_box)
 296         except KeyError:
 297             self.exceptionOccurred(self.tr("Define list \"%1\" not found. Check definition files.").arg(value_list))
 298             self.pageContent.propertyTable.setItem(index, 1, QTableWidgetItem(value))
 299
 300     def insertSpinBox(self, index, value, informations):
 301         """
 302         Inserts in the table at index a spinbox for an int, a long or an unsigned
 303         long property setted to value.
 304         """
 305         # int, long or undefined type property
 306         spin_box = None
 307         if bertos_utils.isLong(informations) or bertos_utils.isUnsignedLong(informations):
 308             spin_box = QDoubleSpinBox()
 309             spin_box.setDecimals(0)
 310         else:
 311             spin_box = QSpinBox()
 312         self.pageContent.propertyTable.setCellWidget(index, 1, spin_box)
 313         minimum = -32768
 314         maximum = 32767
 315         suff = ""
 316         if bertos_utils.isLong(informations):
 317             minimum = -2147483648
 318             maximum = 2147483647
 319             suff = "L"
 320         elif bertos_utils.isUnsigned(informations):
 321             minimum = 0
 322             maximum = 65535
 323             suff = "U"
 324         elif bertos_utils.isUnsignedLong(informations):
 325             minimum = 0
 326             maximum = 4294967295
 327             suff = "UL"
 328         if "min" in informations:
 329             minimum = int(informations["min"])
 330         if "max" in informations:
 331             maximum = int(informations["max"])
 332         spin_box.setRange(minimum, maximum)
 333         spin_box.setSuffix(suff)
 334         spin_box.setValue(int(value.replace("L", "").replace("U", "")))
 335         self._control_group.addControl(index, spin_box)
 336
 337
 338     def currentModule(self):
 339         """
 340         Retuns the current module name.
 341         """
 342         current_module = self.pageContent.moduleTree.currentItem()
 343         # return only the child items
 344         if current_module and current_module.parent():
 345             return unicode(current_module.text(0))
 346         else:
 347             return None
 348
 349     def moduleItem(self, module):
 350         for top_level_index in range(self.pageContent.moduleTree.topLevelItemCount()):
 351             top_level_item = self.pageContent.moduleTree.topLevelItem(top_level_index)
 352             for child_index in range(top_level_item.childCount()):
 353                 child_item = top_level_item.child(child_index)
 354                 if unicode(child_item.text(0)) == module:
 355                     return child_item
 356         return None
 357
 358     def currentModuleConfigurations(self):
 359         """
 360         Returns the current module configuration.
 361         """
 362         return self.configurations(self.currentModule())
 363
 364     def currentProperty(self):
 365         """
 366         Rerturns the current property from the property table.
 367         """
 368         return qvariant_converter.getString(self.pageContent.propertyTable.item(self.pageContent.propertyTable.currentRow(), 0).data(Qt.UserRole))
 369
 370     def currentPropertyItem(self):
 371         """
 372         Returns the QTableWidgetItem of the current property.
 373         """
 374         return self.pageContent.propertyTable.item(self.pageContent.propertyTable.currentRow(), 0)
 375
 376     def configurations(self, module):
 377         """
 378         Returns the configuration for the selected module.
 379         """
 380         configuration = []
 381         if module:
 382             # On linux platform it seems that the behaviour of the focus
 383             # changing is a bit different from the mac one. So if module is
 384             # None then no configurations should be returned.
 385             configuration = self.projectInfo("MODULES")[module]["configuration"]
 386         if len(configuration) > 0:
 387             return self.projectInfo("CONFIGURATIONS")[configuration]
 388         else:
 389             return {}
 390
 391     def resetPropertyDescription(self):
 392         """
 393         Resets the label for each property table entry.
 394         """
 395         for index in range(self.pageContent.propertyTable.rowCount()):
 396             property_name = qvariant_converter.getString(self.pageContent.propertyTable.item(index, 0).data(Qt.UserRole))
 397             # Awful solution! Needed because if the user change the module, the selection changed...
 398             if property_name not in self.currentModuleConfigurations():
 399                 break
 400             self.pageContent.propertyTable.item(index, 0).setText(self.currentModuleConfigurations()[property_name]['brief'])
 401
 402     def setBold(self, item, bold):
 403         self.pageContent.moduleTree.blockSignals(True)
 404         font = item.font(0)
 405         font.setBold(bold)
 406         item.setFont(0, font)
 407         self.pageContent.moduleTree.blockSignals(False)
 408
 409     def moduleSelected(self, selectedModule):
 410         """
 411         Resolves the selection dependencies.
 412         """
 413         try:
 414             qApp.setOverrideCursor(Qt.WaitCursor)
 415             modules = self.projectInfo("MODULES")
 416             modules[selectedModule]["enabled"] = True
 417             self.setProjectInfo("MODULES", modules)
 418             depends = self.projectInfo("MODULES")[selectedModule]["depends"]
 419             unsatisfied = []
 420             if self.pageContent.automaticFix.isChecked():
 421                 unsatisfied = self.selectDependencyCheck(selectedModule)
 422             if len(unsatisfied) > 0:
 423                 for module in unsatisfied:
 424                     modules = self.projectInfo("MODULES")
 425                     modules[module]["enabled"] = True
 426                 for category in range(self.pageContent.moduleTree.topLevelItemCount()):
 427                     item = self.pageContent.moduleTree.topLevelItem(category)
 428                     for child in range(item.childCount()):
 429                         if unicode(item.child(child).text(0)) in unsatisfied:
 430                             self.setBold(item.child(child), True)
 431                             self.setBold(item, True)
 432                             item.child(child).setCheckState(0, Qt.Checked)
 433         finally:
 434             qApp.restoreOverrideCursor()
 435
 436     def moduleUnselected(self, unselectedModule):
 437         """
 438         Resolves the unselection dependencies.
 439         """
 440         try:
 441             qApp.setOverrideCursor(Qt.WaitCursor)
 442             modules = self.projectInfo("MODULES")
 443             modules[unselectedModule]["enabled"] = False
 444             self.setProjectInfo("MODULES", modules)
 445             unsatisfied = []
 446             unsatisfied_params = []
 447             if self.pageContent.automaticFix.isChecked():
 448                 unsatisfied, unsatisfied_params = self.unselectDependencyCheck(unselectedModule)
 449             if len(unsatisfied) > 0 or len(unsatisfied_params) > 0:
 450                 message = []
 451                 heading = self.tr("The module %1 is needed by").arg(unselectedModule)
 452                 message.append(heading)
 453                 module_list = ", ".join(unsatisfied)
 454                 param_list = ", ".join(["%s (%s)" %(param_name, module) for module, param_name in unsatisfied_params])
 455                 if module_list:
 456                     message.append(QString(module_list))
 457                 if module_list and param_list:
 458                     message.append(self.tr("and by"))
 459                 if param_list:
 460                     message.append(QString(param_list))
 461                 message_str = QStringList(message).join(" ")
 462                 message_str.append(self.tr("\n\nDo you want to automatically fix these conflicts?"))
 463                 qApp.restoreOverrideCursor()
 464                 choice = QMessageBox.warning(self, self.tr("Dependency error"), message_str, QMessageBox.Yes | QMessageBox.No, QMessageBox.Yes)
 465                 qApp.setOverrideCursor(Qt.WaitCursor)
 466                 if choice == QMessageBox.Yes:
 467                     for module in unsatisfied:
 468                         modules = self.projectInfo("MODULES")
 469                         modules[module]["enabled"] = False
 470                     for category in range(self.pageContent.moduleTree.topLevelItemCount()):
 471                         item = self.pageContent.moduleTree.topLevelItem(category)
 472                         for child in range(item.childCount()):
 473                             if unicode(item.child(child).text(0)) in unsatisfied:
 474                                 item.child(child).setCheckState(0, Qt.Unchecked)
 475                     for module, param in unsatisfied_params:
 476                         configuration_file = self.projectInfo("MODULES")[module]["configuration"]
 477                         configurations = self.projectInfo("CONFIGURATIONS")
 478                         configurations[configuration_file][param]["value"] = "0"
 479                         self.setProjectInfo("CONFIGURATIONS", configurations)
 480         finally:
 481             qApp.restoreOverrideCursor()
 482
 483     def selectDependencyCheck(self, module):
 484         """
 485         Returns the list of unsatisfied dependencies after a selection.
 486         """
 487         unsatisfied = set()
 488         modules = self.projectInfo("MODULES")
 489         files = self.projectInfo("FILES")
 490         configurations = self.projectInfo("CONFIGURATIONS").get(modules[module]["configuration"], {"paramlist": ()})
 491         conditional_deps = ()
 492         for i, param_name in configurations["paramlist"]:
 493             information = configurations[param_name]
 494             if information["informations"]["type"] == "boolean" and \
 495                 information["value"] != "0" and \
 496                 "conditional_deps" in information["informations"]:
 497
 498                 conditional_deps += information["informations"]["conditional_deps"]
 499
 500         for dependency in modules[module]["depends"] + conditional_deps:
 501             if dependency in modules and not modules[dependency]["enabled"]:
 502                 unsatisfied |= set([dependency])
 503                 if dependency not in unsatisfied:
 504                     unsatisfied |= self.selectDependencyCheck(dependency)
 505             if dependency not in modules:
 506                 if dependency in files:
 507                     files[dependency] += 1
 508                 else:
 509                     files[dependency] = 1
 510         self.setProjectInfo("FILES", files)
 511         return unsatisfied
 512
 513     def unselectDependencyCheck(self, dependency):
 514         """
 515         Returns the list of unsatisfied dependencies after an unselection.
 516         """
 517         unsatisfied = set()
 518         unsatisfied_params = set()
 519         modules = self.projectInfo("MODULES")
 520         for module, informations in modules.items():
 521             configurations = self.projectInfo("CONFIGURATIONS").get(informations["configuration"], {"paramlist": ()})
 522             conditional_deps = {}
 523             for i, param_name in configurations["paramlist"]:
 524                 information = configurations[param_name]
 525                 if information["informations"]["type"] == "boolean" and information["value"] != "0" and "conditional_deps" in information["informations"]:
 526                     for dep in information["informations"]["conditional_deps"]:
 527                         if not dep in conditional_deps:
 528                             conditional_deps[dep] = []
 529                         conditional_deps[dep].append((module, param_name))
 530             if dependency in informations["depends"] and informations["enabled"]:
 531                 unsatisfied |= set([module])
 532                 if dependency not in unsatisfied:
 533                     tmp = self.unselectDependencyCheck(module)
 534                     unsatisfied |= tmp[0]
 535                     unsatisfied_params |= tmp[1]
 536             if dependency in conditional_deps:
 537                 unsatisfied_params |= set(conditional_deps[dependency])
 538         return unsatisfied, unsatisfied_params
 539
 540     def removeFileDependencies(self, module):
 541         """
 542         Removes the files dependencies of the given module.
 543         """
 544         modules = self.projectInfo("MODULES")
 545         files = self.projectInfo("FILES")
 546         dependencies = modules[module]["depends"]
 547         for dependency in dependencies:
 548             if dependency in files:
 549                 files[dependency] -= 1
 550                 if files[dependency] == 0:
 551                     del files[dependency]
 552         self.setProjectInfo("FILES", files)
 553
 554 class QControlGroup(QObject):
 555     """
 556     Simple class that permit to connect different signals of different widgets
 557     with a slot that emit a signal. Permits to group widget and to understand which of
 558     them has sent the signal.
 559     """
 560
 561     def __init__(self):
 562         QObject.__init__(self)
 563         self._controls = {}
 564
 565     def addControl(self, id, control):
 566         """
 567         Add a control.
 568         """
 569         self._controls[id] = control
 570         if type(control) == QCheckBox:
 571             self.connect(control, SIGNAL("stateChanged(int)"), lambda: self.stateChanged(id))
 572         elif type(control) == QSpinBox:
 573             self.connect(control, SIGNAL("valueChanged(int)"), lambda: self.stateChanged(id))
 574         elif type(control) == QComboBox:
 575             self.connect(control, SIGNAL("currentIndexChanged(int)"), lambda: self.stateChanged(id))
 576         elif type(control) == QDoubleSpinBox:
 577             self.connect(control, SIGNAL("valueChanged(double)"), lambda: self.stateChanged(id))
 578
 579     def clear(self):
 580         """
 581         Remove all the controls.
 582         """
 583         self._controls = {}
 584
 585     def stateChanged(self, id):
 586         """
 587         Slot called when the value of one of the stored widget changes. It emits
 588         another signal.
 589         """
 590         self.emit(SIGNAL("stateChanged"), id)