Preferences/ConfigurationDialog.py

# -*- coding: utf-8 -*-

# Copyright (c) 2002 - 2012 Detlev Offenbach <detlev@die-offenbachs.de>
#

"""
Module implementing a dialog for the configuration of eric5.
"""

import os
import types

from PyQt4.QtCore import QMetaObject, pyqtSignal, Qt, QRect, pyqtSlot
from PyQt4.QtGui import QSizePolicy, QSpacerItem, QWidget, QPixmap, QTreeWidget, \
    QStackedWidget, QDialog, QSplitter, QScrollArea, QApplication, QDialogButtonBox, \
    QFrame, QMainWindow, QVBoxLayout, QTreeWidgetItem, QLabel

from E5Gui.E5Application import e5App
from E5Gui import E5MessageBox

import QScintilla.Lexers

import Preferences

from .PreferencesLexer import PreferencesLexer, PreferencesLexerLanguageError
import UI.PixmapCache

from eric5config import getConfig


class ConfigurationPageItem(QTreeWidgetItem):
    """
    Class implementing a QTreeWidgetItem holding the configuration page data.
    """
    def __init__(self, parent, text, pageName, iconFile):
        """
        Constructor
        
        @param parent parent widget of the item (QTreeWidget or QTreeWidgetItem)
        @param text text to be displayed (string)
        @param pageName name of the configuration page (string)
        @param iconFile file name of the icon to be shown (string)
        """
        super().__init__(parent, [text])
        self.setIcon(0, UI.PixmapCache.getIcon(iconFile))
        
        self.__pageName = pageName
        
    def getPageName(self):
        """
        Public method to get the name of the associated configuration page.
        
        @return name of the configuration page (string)
        """
        return self.__pageName


class ConfigurationWidget(QWidget):
    """
    Class implementing a dialog for the configuration of eric5.
    
    @signal preferencesChanged() emitted after settings have been changed
    @signal masterPasswordChanged(str, str) emitted after the master
        password has been changed with the old and the new password
    @signal accepted() emitted to indicate acceptance of the changes
    @signal rejected() emitted to indicate rejection of the changes
    """
    preferencesChanged = pyqtSignal()
    masterPasswordChanged = pyqtSignal(str, str)
    accepted = pyqtSignal()
    rejected = pyqtSignal()
    
    DefaultMode = 0
    HelpBrowserMode = 1
    TrayStarterMode = 2
    
    def __init__(self, parent=None, fromEric=True, displayMode=DefaultMode):
        """
        Constructor
        
        @param parent The parent widget of this dialog. (QWidget)
        @keyparam fromEric flag indicating a dialog generation from within the
            eric5 ide (boolean)
        @keyparam displayMode mode of the configuration dialog
            (DefaultMode, HelpBrowserMode, TrayStarterMode)
        """
        assert displayMode in (
            ConfigurationWidget.DefaultMode,
            ConfigurationWidget.HelpBrowserMode,
            ConfigurationWidget.TrayStarterMode
        )
        
        super().__init__(parent)
        self.fromEric = fromEric
        self.displayMode = displayMode
        
        self.__setupUi()
        
        self.itmDict = {}
        
        if not fromEric:
            from PluginManager.PluginManager import PluginManager
            try:
                self.pluginManager = e5App().getObject("PluginManager")
            except KeyError:
                self.pluginManager = PluginManager(self)
                e5App().registerObject("PluginManager", self.pluginManager)
        
        if displayMode == ConfigurationWidget.DefaultMode:
            self.configItems = {
                # key : [display string, pixmap name, dialog module name or
                #        page creation function, parent key,
                #        reference to configuration page (must always be last)]
                # The dialog module must have the module function create to create
                # the configuration page. This must have the method save to save
                # the settings.
                "applicationPage": \
                    [self.trUtf8("Application"), "preferences-application.png",
                     "ApplicationPage", None, None],
                "cooperationPage": \
                    [self.trUtf8("Cooperation"), "preferences-cooperation.png",
                     "CooperationPage", None, None],
                "corbaPage": \
                    [self.trUtf8("CORBA"), "preferences-orbit.png",
                    "CorbaPage", None, None],
                "emailPage": \
                    [self.trUtf8("Email"), "preferences-mail_generic.png",
                    "EmailPage", None, None],
                "graphicsPage": \
                    [self.trUtf8("Graphics"), "preferences-graphics.png",
                    "GraphicsPage", None, None],
                "iconsPage": \
                    [self.trUtf8("Icons"), "preferences-icons.png",
                    "IconsPage", None, None],
                "networkPage": \
                    [self.trUtf8("Network"), "preferences-network.png",
                    "NetworkPage", None, None],
                "pluginManagerPage": \
                    [self.trUtf8("Plugin Manager"), "preferences-pluginmanager.png",
                    "PluginManagerPage", None, None],
                "printerPage": \
                    [self.trUtf8("Printer"), "preferences-printer.png",
                    "PrinterPage", None, None],
                "py3flakesPage": \
                    [self.trUtf8("PyFlakes"), "warning.png",
                    "Py3FlakesPage", None, None],
                "pythonPage": \
                    [self.trUtf8("Python"), "preferences-python.png",
                    "PythonPage", None, None],
                "qtPage": \
                    [self.trUtf8("Qt"), "preferences-qtlogo.png",
                    "QtPage", None, None],
                "securityPage": \
                    [self.trUtf8("Security"), "preferences-security.png",
                    "SecurityPage", None, None],
                "shellPage": \
                    [self.trUtf8("Shell"), "preferences-shell.png",
                    "ShellPage", None, None],
                "tasksPage": \
                    [self.trUtf8("Tasks"), "task.png",
                    "TasksPage", None, None],
                "templatesPage": \
                    [self.trUtf8("Templates"), "preferences-template.png",
                    "TemplatesPage", None, None],
                "terminalPage": \
                    [self.trUtf8("Terminal"), "terminal.png",
                    "TerminalPage", None, None],
                "trayStarterPage": \
                    [self.trUtf8("Tray Starter"), "erict.png",
                    "TrayStarterPage", None, None],
                "vcsPage": \
                    [self.trUtf8("Version Control Systems"), "preferences-vcs.png",
                    "VcsPage", None, None],
                
                "0debuggerPage": \
                    [self.trUtf8("Debugger"), "preferences-debugger.png",
                    None, None, None],
                "debuggerGeneralPage": \
                    [self.trUtf8("General"), "preferences-debugger.png",
                    "DebuggerGeneralPage", "0debuggerPage", None],
                "debuggerPythonPage": \
                    [self.trUtf8("Python"), "preferences-pyDebugger.png",
                    "DebuggerPythonPage", "0debuggerPage", None],
                "debuggerPython3Page": \
                    [self.trUtf8("Python3"), "preferences-pyDebugger.png",
                    "DebuggerPython3Page", "0debuggerPage", None],
                "debuggerRubyPage": \
                    [self.trUtf8("Ruby"), "preferences-rbDebugger.png",
                    "DebuggerRubyPage", "0debuggerPage", None],
                
                "0editorPage": \
                    [self.trUtf8("Editor"), "preferences-editor.png",
                    None, None, None],
                "editorAPIsPage": \
                    [self.trUtf8("APIs"), "preferences-api.png",
                    "EditorAPIsPage", "0editorPage", None],
                "editorAutocompletionPage": \
                    [self.trUtf8("Autocompletion"), "preferences-autocompletion.png",
                    "EditorAutocompletionPage", "0editorPage", None],
                "editorAutocompletionQScintillaPage": \
                    [self.trUtf8("QScintilla"), "qscintilla.png",
                    "EditorAutocompletionQScintillaPage",
                    "editorAutocompletionPage", None],
                "editorCalltipsPage": \
                    [self.trUtf8("Calltips"), "preferences-calltips.png",
                    "EditorCalltipsPage", "0editorPage", None],
                "editorCalltipsQScintillaPage": \
                    [self.trUtf8("QScintilla"), "qscintilla.png",
                    "EditorCalltipsQScintillaPage", "editorCalltipsPage", None],
                "editorGeneralPage": \
                    [self.trUtf8("General"), "preferences-general.png",
                    "EditorGeneralPage", "0editorPage", None],
                "editorFilePage": \
                    [self.trUtf8("Filehandling"), "preferences-filehandling.png",
                    "EditorFilePage", "0editorPage", None],
                "editorSearchPage": \
                    [self.trUtf8("Searching"), "preferences-search.png",
                    "EditorSearchPage", "0editorPage", None],
                "editorSpellCheckingPage": \
                    [self.trUtf8("Spell checking"), "preferences-spellchecking.png",
                    "EditorSpellCheckingPage", "0editorPage", None],
                "editorStylesPage": \
                    [self.trUtf8("Style"), "preferences-styles.png",
                    "EditorStylesPage", "0editorPage", None],
                "editorSyntaxPage": \
                    [self.trUtf8("Syntax Checker"), "preferences-debugger.png",
                    "EditorSyntaxPage", "0editorPage", None],
                "editorTypingPage": \
                    [self.trUtf8("Typing"), "preferences-typing.png",
                    "EditorTypingPage", "0editorPage", None],
                "editorExportersPage": \
                    [self.trUtf8("Exporters"), "preferences-exporters.png",
                    "EditorExportersPage", "0editorPage", None],
                
                "1editorLexerPage": \
                    [self.trUtf8("Highlighters"), "preferences-highlighting-styles.png",
                    None, "0editorPage", None],
                "editorHighlightersPage": \
                    [self.trUtf8("Filetype Associations"),
                    "preferences-highlighter-association.png",
                    "EditorHighlightersPage", "1editorLexerPage", None],
                "editorHighlightingStylesPage": \
                    [self.trUtf8("Styles"),
                    "preferences-highlighting-styles.png",
                    "EditorHighlightingStylesPage", "1editorLexerPage", None],
                "editorKeywordsPage": \
                    [self.trUtf8("Keywords"), "preferences-keywords.png",
                     "EditorKeywordsPage", "1editorLexerPage", None],
                "editorPropertiesPage": \
                    [self.trUtf8("Properties"), "preferences-properties.png",
                    "EditorPropertiesPage", "1editorLexerPage", None],
                
                "0helpPage": \
                    [self.trUtf8("Help"), "preferences-help.png",
                    None, None, None],
                "helpAppearancePage": \
                    [self.trUtf8("Appearance"), "preferences-styles.png",
                    "HelpAppearancePage", "0helpPage", None],
                "helpDocumentationPage": \
                    [self.trUtf8("Help Documentation"),
                    "preferences-helpdocumentation.png",
                    "HelpDocumentationPage", "0helpPage", None],
                "helpViewersPage": \
                    [self.trUtf8("Help Viewers"), "preferences-helpviewers.png",
                    "HelpViewersPage", "0helpPage", None],
                "helpVirusTotalPage": \
                    [self.trUtf8("VirusTotal Interface"), "virustotal.png",
                    "HelpVirusTotalPage", "0helpPage", None],
                "helpWebBrowserPage": \
                    [self.trUtf8("eric5 Web Browser"), "ericWeb.png",
                    "HelpWebBrowserPage", "0helpPage", None],
                
                "0projectPage": \
                    [self.trUtf8("Project"), "preferences-project.png",
                    None, None, None],
                "projectBrowserPage": \
                    [self.trUtf8("Project Viewer"), "preferences-project.png",
                    "ProjectBrowserPage", "0projectPage", None],
                "projectPage": \
                    [self.trUtf8("Project"), "preferences-project.png",
                    "ProjectPage", "0projectPage", None],
                "multiProjectPage": \
                    [self.trUtf8("Multiproject"), "preferences-multiproject.png",
                    "MultiProjectPage", "0projectPage", None],
                
                "0interfacePage": \
                    [self.trUtf8("Interface"), "preferences-interface.png",
                    None, None, None],
                "interfacePage": \
                    [self.trUtf8("Interface"), "preferences-interface.png",
                    "InterfacePage", "0interfacePage", None],
                "viewmanagerPage": \
                    [self.trUtf8("Viewmanager"), "preferences-viewmanager.png",
                    "ViewmanagerPage", "0interfacePage", None],
            }
            
            self.configItems.update(
                e5App().getObject("PluginManager").getPluginConfigData())
        elif displayMode == ConfigurationWidget.HelpBrowserMode:
            self.configItems = {
                # key : [display string, pixmap name, dialog module name or
                #        page creation function, parent key,
                #        reference to configuration page (must always be last)]
                # The dialog module must have the module function create to create
                # the configuration page. This must have the method save to save
                # the settings.
                "networkPage": \
                    [self.trUtf8("Network"), "preferences-network.png",
                     "NetworkPage", None, None],
                "printerPage": \
                    [self.trUtf8("Printer"), "preferences-printer.png",
                    "PrinterPage", None, None],
                "securityPage": \
                    [self.trUtf8("Security"), "preferences-security.png",
                    "SecurityPage", None, None],
                
                "0helpPage": \
                    [self.trUtf8("Help"), "preferences-help.png",
                    None, None, None],
                "helpAppearancePage": \
                    [self.trUtf8("Appearance"), "preferences-styles.png",
                    "HelpAppearancePage", "0helpPage", None],
                "helpDocumentationPage": \
                    [self.trUtf8("Help Documentation"),
                    "preferences-helpdocumentation.png",
                    "HelpDocumentationPage", "0helpPage", None],
                "helpVirusTotalPage": \
                    [self.trUtf8("VirusTotal Interface"), "virustotal.png",
                    "HelpVirusTotalPage", "0helpPage", None],
                "helpWebBrowserPage": \
                    [self.trUtf8("eric5 Web Browser"), "ericWeb.png",
                    "HelpWebBrowserPage", "0helpPage", None],
            }
        elif displayMode == ConfigurationWidget.TrayStarterMode:
            self.configItems = {
                # key : [display string, pixmap name, dialog module name or
                #        page creation function, parent key,
                #        reference to configuration page (must always be last)]
                # The dialog module must have the module function create to create
                # the configuration page. This must have the method save to save
                # the settings.
                "trayStarterPage": \
                    [self.trUtf8("Tray Starter"), "erict.png",
                    "TrayStarterPage", None, None],
            }
        else:
            raise RuntimeError("Illegal mode value: {0}".format(displayMode))
        
        # generate the list entries
        for key in sorted(self.configItems.keys()):
            pageData = self.configItems[key]
            if pageData[3]:
                pitm = self.itmDict[pageData[3]]  # get the parent item
            else:
                pitm = self.configList
            self.itmDict[key] = ConfigurationPageItem(pitm, pageData[0], key, pageData[1])
            self.itmDict[key].setExpanded(True)
        self.configList.sortByColumn(0, Qt.AscendingOrder)
        
        # set the initial size of the splitter
        self.configSplitter.setSizes([200, 600])
        
        self.configList.itemActivated.connect(self.__showConfigurationPage)
        self.configList.itemClicked.connect(self.__showConfigurationPage)
        self.buttonBox.accepted.connect(self.accept)
        self.buttonBox.rejected.connect(self.rejected)
        
        if displayMode != ConfigurationWidget.TrayStarterMode:
            self.__initLexers()
        
    def accept(self):
        """
        Public slot to accept the buttonBox accept signal.
        """
        wdg = self.focusWidget()
        if wdg == self.configList:
            return
        
        self.accepted.emit()
        
    def __setupUi(self):
        """
        Private method to perform the general setup of the configuration widget.
        """
        self.setObjectName("ConfigurationDialog")
        self.resize(900, 650)
        self.verticalLayout_2 = QVBoxLayout(self)
        self.verticalLayout_2.setSpacing(6)
        self.verticalLayout_2.setMargin(6)
        self.verticalLayout_2.setObjectName("verticalLayout_2")
        
        self.configSplitter = QSplitter(self)
        self.configSplitter.setOrientation(Qt.Horizontal)
        self.configSplitter.setObjectName("configSplitter")
        
        self.configList = QTreeWidget(self.configSplitter)
        self.configList.setObjectName("configList")
        
        self.scrollArea = QScrollArea(self.configSplitter)
        self.scrollArea.setFrameShape(QFrame.NoFrame)
        self.scrollArea.setVerticalScrollBarPolicy(Qt.ScrollBarAlwaysOn)
        self.scrollArea.setHorizontalScrollBarPolicy(Qt.ScrollBarAlwaysOn)
        self.scrollArea.setWidgetResizable(False)
        self.scrollArea.setObjectName("scrollArea")
        
        self.configStack = QStackedWidget()
        self.configStack.setFrameShape(QFrame.Box)
        self.configStack.setFrameShadow(QFrame.Sunken)
        self.configStack.setObjectName("configStack")
        self.scrollArea.setWidget(self.configStack)
        
        self.emptyPage = QWidget()
        self.emptyPage.setGeometry(QRect(0, 0, 372, 591))
        self.emptyPage.setObjectName("emptyPage")
        self.vboxlayout = QVBoxLayout(self.emptyPage)
        self.vboxlayout.setSpacing(6)
        self.vboxlayout.setMargin(6)
        self.vboxlayout.setObjectName("vboxlayout")
        spacerItem = QSpacerItem(20, 20, QSizePolicy.Minimum, QSizePolicy.Expanding)
        self.vboxlayout.addItem(spacerItem)
        self.emptyPagePixmap = QLabel(self.emptyPage)
        self.emptyPagePixmap.setAlignment(Qt.AlignCenter)
        self.emptyPagePixmap.setObjectName("emptyPagePixmap")
        self.emptyPagePixmap.setPixmap(
            QPixmap(os.path.join(getConfig('ericPixDir'), 'eric.png')))
        self.vboxlayout.addWidget(self.emptyPagePixmap)
        self.textLabel1 = QLabel(self.emptyPage)
        self.textLabel1.setAlignment(Qt.AlignCenter)
        self.textLabel1.setObjectName("textLabel1")
        self.vboxlayout.addWidget(self.textLabel1)
        spacerItem1 = QSpacerItem(20, 40, QSizePolicy.Minimum, QSizePolicy.Expanding)
        self.vboxlayout.addItem(spacerItem1)
        self.configStack.addWidget(self.emptyPage)
        
        self.verticalLayout_2.addWidget(self.configSplitter)
        
        self.buttonBox = QDialogButtonBox(self)
        self.buttonBox.setOrientation(Qt.Horizontal)
        self.buttonBox.setStandardButtons(
            QDialogButtonBox.Apply | QDialogButtonBox.Cancel | \
            QDialogButtonBox.Ok | QDialogButtonBox.Reset)
        self.buttonBox.setObjectName("buttonBox")
        if not self.fromEric and self.displayMode == ConfigurationWidget.DefaultMode:
            self.buttonBox.button(QDialogButtonBox.Apply).hide()
        self.buttonBox.button(QDialogButtonBox.Apply).setEnabled(False)
        self.buttonBox.button(QDialogButtonBox.Reset).setEnabled(False)
        self.verticalLayout_2.addWidget(self.buttonBox)

        self.setWindowTitle(self.trUtf8("Preferences"))
        
        self.configList.header().hide()
        self.configList.header().setSortIndicator(0, Qt.AscendingOrder)
        self.configList.setSortingEnabled(True)
        self.textLabel1.setText(self.trUtf8("Please select an entry of the list \n"
            "to display the configuration page."))
        
        QMetaObject.connectSlotsByName(self)
        self.setTabOrder(self.configList, self.configStack)
        
        self.configStack.setCurrentWidget(self.emptyPage)
    
    def __initLexers(self):
        """
        Private method to initialize the dictionary of preferences lexers.
        """
        self.lexers = {}
        for language in QScintilla.Lexers.getSupportedLanguages():
            if language not in self.lexers:
                try:
                    self.lexers[language] = PreferencesLexer(language, self)
                except PreferencesLexerLanguageError:
                    pass
        
    def __importConfigurationPage(self, name):
        """
        Private method to import a configuration page module.
        
        @param name name of the configuration page module (string)
        @return reference to the configuration page module
        """
        modName = "Preferences.ConfigurationPages.{0}".format(name)
        try:
            mod = __import__(modName)
            components = modName.split('.')
            for comp in components[1:]:
                mod = getattr(mod, comp)
            return mod
        except ImportError:
            E5MessageBox.critical(self,
                self.trUtf8("Configuration Page Error"),
                self.trUtf8("""<p>The configuration page <b>{0}</b>"""
                            """ could not be loaded.</p>""").format(name))
            return None
        
    def __showConfigurationPage(self, itm, column):
        """
        Private slot to show a selected configuration page.
        
        @param itm reference to the selected item (QTreeWidgetItem)
        @param column column that was selected (integer) (ignored)
        """
        pageName = itm.getPageName()
        self.showConfigurationPageByName(pageName, setCurrent=False)
        
    def __initPage(self, pageData):
        """
        Private method to initialize a configuration page.
        
        @param pageData data structure for the page to initialize
        @return reference to the initialized page
        """
        page = None
        if isinstance(pageData[2], types.FunctionType):
            page = pageData[2](self)
        else:
            mod = self.__importConfigurationPage(pageData[2])
            if mod:
                page = mod.create(self)
        if page is not None:
            self.configStack.addWidget(page)
            pageData[-1] = page
            try:
                page.setMode(self.displayMode)
            except AttributeError:
                pass
        return page
        
    def showConfigurationPageByName(self, pageName, setCurrent=True):
        """
        Public slot to show a named configuration page.
        
        @param pageName name of the configuration page to show (string)
        @param setCurrent flag indicating to set the current item (boolean)
        """
        if pageName == "empty":
            page = self.emptyPage
        else:
            pageData = self.configItems[pageName]
            if pageData[-1] is None and pageData[2] is not None:
                # the page was not loaded yet, create it
                page = self.__initPage(pageData)
            else:
                page = pageData[-1]
            if page is None:
                page = self.emptyPage
            elif setCurrent:
                items = self.configList.findItems(pageData[0],
                    Qt.MatchFixedString | Qt.MatchRecursive)
                if items:
                    self.configList.setCurrentItem(items[0])
        self.configStack.setCurrentWidget(page)
        ssize = self.scrollArea.size()
        if self.scrollArea.horizontalScrollBar():
            ssize.setHeight(
                ssize.height() - self.scrollArea.horizontalScrollBar().height() - 2)
        if self.scrollArea.verticalScrollBar():
            ssize.setWidth(
                ssize.width() - self.scrollArea.verticalScrollBar().width() - 2)
        psize = page.minimumSizeHint()
        self.configStack.resize(max(ssize.width(), psize.width()),
                                max(ssize.height(), psize.height()))
        
        if page != self.emptyPage:
            page.polishPage()
            self.buttonBox.button(QDialogButtonBox.Apply).setEnabled(True)
            self.buttonBox.button(QDialogButtonBox.Reset).setEnabled(True)
        else:
            self.buttonBox.button(QDialogButtonBox.Apply).setEnabled(False)
            self.buttonBox.button(QDialogButtonBox.Reset).setEnabled(False)
        
        # reset scrollbars
        for sb in [self.scrollArea.horizontalScrollBar(),
                   self.scrollArea.verticalScrollBar()]:
            if sb:
                sb.setValue(0)
        
        self.__currentConfigurationPageName = pageName
        
    def getConfigurationPageName(self):
        """
        Public method to get the page name of the current page.
        
        @param page name of the current page (string)
        """
        return self.__currentConfigurationPageName
        
    def calledFromEric(self):
        """
        Public method to check, if invoked from within eric.
        
        @return flag indicating invocation from within eric (boolean)
        """
        return self.fromEric
        
    def getPage(self, pageName):
        """
        Public method to get a reference to the named page.
        
        @param pageName name of the configuration page (string)
        @return reference to the page or None, indicating page was
            not loaded yet
        """
        return self.configItems[pageName][-1]
        
    def getLexers(self):
        """
        Public method to get a reference to the lexers dictionary.
        
        @return reference to the lexers dictionary
        """
        return self.lexers
        
    def setPreferences(self):
        """
        Public method called to store the selected values into the preferences storage.
        """
        for key, pageData in list(self.configItems.items()):
            if pageData[-1]:
                pageData[-1].save()
                # page was loaded (and possibly modified)
                QApplication.processEvents()    # ensure HMI is responsive
        
    def on_buttonBox_clicked(self, button):
        """
        Private slot called by a button of the button box clicked.
        
        @param button button that was clicked (QAbstractButton)
        """
        if button == self.buttonBox.button(QDialogButtonBox.Apply):
            self.on_applyButton_clicked()
        elif button == self.buttonBox.button(QDialogButtonBox.Reset):
            self.on_resetButton_clicked()
        
    @pyqtSlot()
    def on_applyButton_clicked(self):
        """
        Private slot called to apply the settings of the current page.
        """
        if self.configStack.currentWidget() != self.emptyPage:
            page = self.configStack.currentWidget()
            savedState = page.saveState()
            page.save()
            self.preferencesChanged.emit()
            if savedState is not None:
                page.setState(savedState)
        
    @pyqtSlot()
    def on_resetButton_clicked(self):
        """
        Private slot called to reset the settings of the current page.
        """
        if self.configStack.currentWidget() != self.emptyPage:
            currentPage = self.configStack.currentWidget()
            savedState = currentPage.saveState()
            pageName = self.configList.currentItem().getPageName()
            self.configStack.removeWidget(currentPage)
            if pageName == "editorHighlightingStylesPage":
                self.__initLexers()
            self.configItems[pageName][-1] = None
            
            self.showConfigurationPageByName(pageName)
            if savedState is not None:
                self.configStack.currentWidget().setState(savedState)


class ConfigurationDialog(QDialog):
    """
    Class for the dialog variant.
    
    @signal preferencesChanged() emitted after settings have been changed
    @signal masterPasswordChanged(str, str) emitted after the master
        password has been changed with the old and the new password
    """
    preferencesChanged = pyqtSignal()
    masterPasswordChanged = pyqtSignal(str, str)
    
    DefaultMode = ConfigurationWidget.DefaultMode
    HelpBrowserMode = ConfigurationWidget.HelpBrowserMode
    TrayStarterMode = ConfigurationWidget.TrayStarterMode
    
    def __init__(self, parent=None, name=None, modal=False,
                 fromEric=True, displayMode=ConfigurationWidget.DefaultMode):
        """
        Constructor
        
        @param parent The parent widget of this dialog. (QWidget)
        @param name The name of this dialog. string
        @param modal Flag indicating a modal dialog. (boolean)
        @keyparam fromEric flag indicating a dialog generation from within the
            eric5 ide (boolean)
        @keyparam displayMode mode of the configuration dialog
            (DefaultMode, HelpBrowserMode, TrayStarterMode)
        """
        super().__init__(parent)
        if name:
            self.setObjectName(name)
        self.setModal(modal)
        self.layout = QVBoxLayout(self)
        self.layout.setMargin(0)
        self.layout.setSpacing(0)
        
        self.cw = ConfigurationWidget(self, fromEric=fromEric,
                                      displayMode=displayMode)
        size = self.cw.size()
        self.layout.addWidget(self.cw)
        self.resize(size)
        
        self.cw.accepted[()].connect(self.accept)
        self.cw.rejected[()].connect(self.reject)
        self.cw.preferencesChanged.connect(self.__preferencesChanged)
        self.cw.masterPasswordChanged.connect(self.__masterPasswordChanged)
        
    def __preferencesChanged(self):
        """
        Private slot to handle a change of the preferences.
        """
        self.preferencesChanged.emit()
        
    def __masterPasswordChanged(self, oldPassword, newPassword):
        """
        Private slot to handle the change of the master password.
        
        @param oldPassword current master password (string)
        @param newPassword new master password (string)
        """
        self.masterPasswordChanged.emit(oldPassword, newPassword)
        
    def showConfigurationPageByName(self, pageName):
        """
        Public slot to show a named configuration page.
        
        @param pageName name of the configuration page to show (string)
        """
        self.cw.showConfigurationPageByName(pageName)
        
    def getConfigurationPageName(self):
        """
        Public method to get the page name of the current page.
        
        @param page name of the current page (string)
        """
        return self.cw.getConfigurationPageName()
        
    def setPreferences(self):
        """
        Public method called to store the selected values into the preferences storage.
        """
        self.cw.setPreferences()
    
    def accept(self):
        super().accept()


class ConfigurationWindow(QMainWindow):
    """
    Main window class for the standalone dialog.
    """
    def __init__(self, parent=None):
        """
        Constructor
        
        @param parent reference to the parent widget (QWidget)
        """
        super().__init__(parent)
        
        self.cw = ConfigurationWidget(self, fromEric=False)
        size = self.cw.size()
        self.setCentralWidget(self.cw)
        self.resize(size)
        
        self.cw.accepted[()].connect(self.accept)
        self.cw.rejected[()].connect(self.close)
        
    def showConfigurationPageByName(self, pageName):
        """
        Public slot to show a named configuration page.
        
        @param pageName name of the configuration page to show (string)
        """
        self.cw.showConfigurationPageByName(pageName)
        
    def accept(self):
        """
        Protected slot called by the Ok button.
        """
        self.cw.setPreferences()
        Preferences.saveResetLayout()
        Preferences.syncPreferences()
        self.close()