view frontends/src/tools/xmlui.py @ 1122:9ae01ccf89c1

core: sat bakcend is now a twisted plugin (no more .tac file)
author Goffi <goffi@goffi.org>
date Sun, 24 Aug 2014 18:44:17 +0200
parents 0a448c947038
children f91e7028e2c3
line wrap: on
line source

#!/usr/bin/python
# -*- coding: utf-8 -*-

# SàT frontend tools
# Copyright (C) 2009, 2010, 2011, 2012, 2013, 2014 Jérôme Poisson (goffi@goffi.org)

# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.

# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU Affero General Public License for more details.

# You should have received a copy of the GNU Affero General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

from sat.core.i18n import _
from sat.core.log import getLogger
log = getLogger(__name__)
from sat_frontends.constants import Const as C
from sat.core.exceptions import DataError


class_map = {}
CLASS_PANEL = 'panel'
CLASS_DIALOG = 'dialog'

class InvalidXMLUI(Exception):
    pass


class ClassNotRegistedError(Exception):
    pass

def getText(node):
    """Get child text nodes
    @param node: dom Node
    @return: joined unicode text of all nodes

    """
    data = []
    for child in node.childNodes:
        if child.nodeType == child.TEXT_NODE:
            data.append(child.wholeText)
    return u"".join(data)


class Widget(object):
    """base Widget"""
    pass


class EmptyWidget(Widget):
    """Just a placeholder widget"""
    pass


class TextWidget(Widget):
    """Non interactive text"""
    pass


class LabelWidget(Widget):
    """Non interactive text"""
    pass


class JidWidget(Widget):
    """Jabber ID"""
    pass


class DividerWidget(Widget):
    """Separator"""
    pass


class StringWidget(Widget):
    """Input widget wich require a string

    often called Edit in toolkits
    """


class PasswordWidget(Widget):
    """Input widget with require a masked string"""


class TextBoxWidget(Widget):
    """Input widget with require a long, possibly multilines string
    often called TextArea in toolkits
    """


class BoolWidget(Widget):
    """Input widget with require a boolean value
    often called CheckBox in toolkits
    """


class ButtonWidget(Widget):
    """A clickable widget"""


class ListWidget(Widget):
    """A widget able to show/choose one or several strings in a list"""


class Container(Widget):
    """Widget which can contain other ones with a specific layout"""

    @classmethod
    def _xmluiAdapt(cls, instance):
        """Make cls as instance.__class__

        cls must inherit from original instance class
        Usefull when you get a class from UI toolkit
        """
        assert instance.__class__ in cls.__bases__
        instance.__class__ = type(cls.__name__, cls.__bases__, dict(cls.__dict__))


class PairsContainer(Container):
    """Widgets are disposed in rows of two (usually label/input) """


class TabsContainer(Container):
    """A container which several other containers in tabs

    Often called Notebook in toolkits
    """

class VerticalContainer(Container):
    """Widgets are disposed vertically"""


class AdvancedListContainer(Container):
    """Widgets are disposed in rows with advaned features"""


class Dialog(object):
    """base dialog"""

    def __init__(self, _xmlui_parent):
        self._xmlui_parent = _xmlui_parent

    def _xmluiValidated(self, data=None):
        if data is None:
            data = {}
        self._xmluiSetData(C.XMLUI_STATUS_VALIDATED, data)
        self._xmluiSubmit(data)
        self._xmluiClose()

    def _xmluiCancelled(self):
        data = {C.XMLUI_DATA_CANCELLED: C.BOOL_TRUE}
        self._xmluiSetData(C.XMLUI_STATUS_CANCELLED, data)
        self._xmluiSubmit(data)
        self._xmluiClose()

    def _xmluiSubmit(self, data):
        if self._xmlui_parent.submit_id is None:
            log.debug(_("Nothing to submit"))
        else:
            self._xmlui_parent.submit(data)

    def _xmluiSetData(self, status, data):
        pass


class MessageDialog(Dialog):
    """Dialog with a OK/Cancel type configuration"""


class NoteDialog(Dialog):
    """Dialog with a OK/Cancel type configuration"""


class ConfirmDialog(Dialog):
    """Dialog with a OK/Cancel type configuration"""

    def _xmluiSetData(self, status, data):
        if status == C.XMLUI_STATUS_VALIDATED:
            data[C.XMLUI_DATA_ANSWER] = C.BOOL_TRUE
        elif status == C.XMLUI_STATUS_CANCELLED:
            data[C.XMLUI_DATA_ANSWER] = C.BOOL_FALSE


class FileDialog(Dialog):
    """Dialog with a OK/Cancel type configuration"""


class XMLUIBase(object):
    """Base class to construct SàT XML User Interface

    This class must not be instancied directly
    """

    def __init__(self, host, parsed_dom, title = None, flags = None):
        """Initialise the XMLUI instance

        @param host: %(doc_host)s
        @param parsed_dom: main parsed dom
        @param title: force the title, or use XMLUI one if None
        @param flags: list of string which can be:
            - NO_CANCEL: the UI can't be cancelled
        """
        self.host = host
        top=parsed_dom.documentElement
        self.session_id = top.getAttribute("session_id") or None
        self.submit_id = top.getAttribute("submit") or None
        self.title = title or top.getAttribute("title") or u""
        if flags is None:
            flags = []
        self.flags = flags

    def _isAttrSet(self, name, node):
        """Returnw widget boolean attribute status

        @param name: name of the attribute (e.g. "read_only")
        @param node: Node instance
        @return (bool): True if widget's attribute is set (C.BOOL_TRUE)
        """
        read_only = node.getAttribute(name) or C.BOOL_FALSE
        return read_only.lower().strip() == C.BOOL_TRUE

    def _getChildNode(self, node, name):
        """Return the first child node with the given name

        @param node: Node instance
        @param name: name of the wanted node

        @return: The found element or None
        """
        for child in node.childNodes:
            if child.nodeName == name:
                return child
        return None

    def submit(self, data):
        if self.submit_id is None:
            raise ValueError("Can't submit is self.submit_id is not set")
        if "session_id" in data:
            raise ValueError("session_id must no be used in data, it is automaticaly filled with self.session_id if present")
        if self.session_id is not None:
            data["session_id"] = self.session_id
        self._xmluiLaunchAction(self.submit_id, data)

    def _xmluiLaunchAction(self, action_id, data):
        self.host.launchAction(action_id, data, profile_key = self.host.profile)


class XMLUIPanel(XMLUIBase):
    """XMLUI Panel

    New frontends can inherite this class to easily implement XMLUI
    @property widget_factory: factory to create frontend-specific widgets
    @proporety dialog_factory: factory to create frontend-specific dialogs
    """
    widget_factory = None

    def __init__(self, host, parsed_dom, title = None, flags = None):
        super(XMLUIPanel, self).__init__(host, parsed_dom, title = None, flags = None)
        self.ctrl_list = {}  # usefull to access ctrl
        self._main_cont = None
        self.constructUI(parsed_dom)

    def escape(self, name):
        """Return escaped name for forms"""
        return u"%s%s" % (C.SAT_FORM_PREFIX, name)

    @property
    def main_cont(self):
        return self._main_cont

    @main_cont.setter
    def main_cont(self, value):
        if self._main_cont is not None:
            raise ValueError(_("XMLUI can have only one main container"))
        self._main_cont = value

    def _parseChilds(self, _xmlui_parent, current_node, wanted = ('container',), data = None):
        """Recursively parse childNodes of an elemen

        @param _xmlui_parent: widget container with '_xmluiAppend' method
        @param current_node: element from which childs will be parsed
        @param wanted: list of tag names that can be present in the childs to be SàT XMLUI compliant
        @param data: additionnal data which are needed in some cases
        """
        for node in current_node.childNodes:
            if wanted and not node.nodeName in wanted:
                raise InvalidXMLUI('Unexpected node: [%s]' % node.nodeName)

            if node.nodeName == "container":
                type_ = node.getAttribute('type')
                if _xmlui_parent is self and type_ != 'vertical':
                    # main container is not a VerticalContainer and we want one, so we create one to wrap it
                    _xmlui_parent = self.widget_factory.createVerticalContainer(self)
                    self.main_cont = _xmlui_parent
                if type_ == "tabs":
                    cont = self.widget_factory.createTabsContainer(_xmlui_parent)
                    self._parseChilds(_xmlui_parent, node, ('tab',), cont)
                elif type_ == "vertical":
                    cont = self.widget_factory.createVerticalContainer(_xmlui_parent)
                    self._parseChilds(cont, node, ('widget', 'container'))
                elif type_ == "pairs":
                    cont = self.widget_factory.createPairsContainer(_xmlui_parent)
                    self._parseChilds(cont, node, ('widget', 'container'))
                elif type_ == "advanced_list":
                    try:
                        columns = int(node.getAttribute('columns'))
                    except (TypeError, ValueError):
                        raise DataError("Invalid columns")
                    selectable = node.getAttribute('selectable') or 'no'
                    auto_index = node.getAttribute('auto_index') == C.BOOL_TRUE
                    data = {'index': 0} if auto_index else None
                    cont = self.widget_factory.createAdvancedListContainer(_xmlui_parent, columns, selectable)
                    callback_id = node.getAttribute("callback") or None
                    if callback_id is not None:
                        if selectable == 'no':
                            raise ValueError("can't have selectable=='no' and callback_id at the same time")
                        cont._xmlui_callback_id = callback_id
                        cont._xmluiOnSelect(self.onAdvListSelect)

                    self._parseChilds(cont, node, ('row',), data)
                else:
                    log.warning(_("Unknown container [%s], using default one") % type_)
                    cont = self.widget_factory.createVerticalContainer(_xmlui_parent)
                    self._parseChilds(cont, node, ('widget', 'container'))
                try:
                    _xmlui_parent._xmluiAppend(cont)
                except (AttributeError, TypeError): # XXX: TypeError is here because pyjamas raise a TypeError instead of an AttributeError
                    if _xmlui_parent is self:
                        self.main_cont = cont
                    else:
                        raise Exception(_("Internal Error, container has not _xmluiAppend method"))

            elif node.nodeName == 'tab':
                name = node.getAttribute('name')
                label = node.getAttribute('label')
                if not name or not isinstance(data, TabsContainer):
                    raise InvalidXMLUI
                if self.type == 'param':
                    self._current_category = name #XXX: awful hack because params need category and we don't keep parent
                tab_cont = data
                new_tab = tab_cont._xmluiAddTab(label or name)
                self._parseChilds(new_tab, node, ('widget', 'container'))

            elif node.nodeName == 'row':
                try:
                    index = str(data['index'])
                    data['index'] += 1
                except TypeError:
                    index = node.getAttribute('index') or None
                _xmlui_parent._xmluiAddRow(index)
                self._parseChilds(_xmlui_parent, node, ('widget', 'container'))

            elif node.nodeName == "widget":
                name = node.getAttribute("name")
                type_ = node.getAttribute("type")
                value_elt = self._getChildNode(node, "value")
                if value_elt is not None:
                    value = getText(value_elt)
                else:
                    value = node.getAttribute("value") if node.hasAttribute('value') else u''
                if type_=="empty":
                    ctrl = self.widget_factory.createEmptyWidget(_xmlui_parent)
                elif type_=="text":
                    ctrl = self.widget_factory.createTextWidget(_xmlui_parent, value)
                elif type_=="label":
                    ctrl = self.widget_factory.createLabelWidget(_xmlui_parent, value)
                elif type_=="jid":
                    ctrl = self.widget_factory.createJidWidget(_xmlui_parent, value)
                elif type_=="divider":
                    style = node.getAttribute("style") or 'line'
                    ctrl = self.widget_factory.createDividerWidget(_xmlui_parent, style)
                elif type_=="string":
                    ctrl = self.widget_factory.createStringWidget(_xmlui_parent, value, self._isAttrSet("read_only", node))
                    self.ctrl_list[name] = ({'type':type_, 'control':ctrl})
                elif type_=="password":
                    ctrl = self.widget_factory.createPasswordWidget(_xmlui_parent, value, self._isAttrSet("read_only", node))
                    self.ctrl_list[name] = ({'type':type_, 'control':ctrl})
                elif type_=="textbox":
                    ctrl = self.widget_factory.createTextBoxWidget(_xmlui_parent, value, self._isAttrSet("read_only", node))
                    self.ctrl_list[name] = ({'type':type_, 'control':ctrl})
                elif type_=="bool":
                    ctrl = self.widget_factory.createBoolWidget(_xmlui_parent, value==C.BOOL_TRUE, self._isAttrSet("read_only", node))
                    self.ctrl_list[name] = ({'type':type_, 'control':ctrl})
                elif type_ == "list":
                    style = [] if node.getAttribute("multi") == 'yes' else ['single']
                    _options = [(option.getAttribute("value"), option.getAttribute("label")) for option in node.getElementsByTagName("option")]
                    _selected = [option.getAttribute("value") for option in node.getElementsByTagName("option") if option.getAttribute('selected') == C.BOOL_TRUE]
                    ctrl = self.widget_factory.createListWidget(_xmlui_parent, _options, _selected, style)
                    self.ctrl_list[name] = ({'type': type_, 'control': ctrl})
                elif type_=="button":
                    callback_id = node.getAttribute("callback")
                    ctrl = self.widget_factory.createButtonWidget(_xmlui_parent, value, self.onButtonPress)
                    ctrl._xmlui_param_id = (callback_id, [field.getAttribute('name') for field in node.getElementsByTagName("field_back")])
                else:
                    log.error(_("FIXME FIXME FIXME: widget type [%s] is not implemented") % type_)
                    raise NotImplementedError(_("FIXME FIXME FIXME: type [%s] is not implemented") % type_)

                if self.type == 'param' and type_ not in ('text', 'button'):
                    try:
                        ctrl._xmluiOnChange(self.onParamChange)
                        ctrl._param_category = self._current_category
                    except (AttributeError, TypeError):  # XXX: TypeError is here because pyjamas raise a TypeError instead of an AttributeError
                        if not isinstance(ctrl, (EmptyWidget, TextWidget, LabelWidget, JidWidget)):
                            log.warning(_("No change listener on [%s]") % ctrl)

                if type_ != 'text':
                    callback = node.getAttribute("internal_callback") or None
                    if callback:
                        fields = [field.getAttribute('name') for field in node.getElementsByTagName("internal_field")]
                        data = self.getInternalCallbackData(callback, node)
                        ctrl._xmlui_param_internal = (callback, fields, data)
                        if type_ == 'button':
                            ctrl._xmluiOnClick(self.onChangeInternal)
                        else:
                            ctrl._xmluiOnChange(self.onChangeInternal)

                ctrl._xmlui_name = name
                _xmlui_parent._xmluiAppend(ctrl)

            else:
                raise NotImplementedError(_('Unknown tag [%s]') % node.nodeName)

    def constructUI(self, parsed_dom, post_treat=None):
        """Actually construct the UI

        @param parsed_dom: main parsed dom
        @param post_treat: frontend specific treatments to do once the UI is constructed
        @return: constructed widget
        """
        top=parsed_dom.documentElement
        self.type = top.getAttribute("type")
        if top.nodeName != "sat_xmlui" or not self.type in ['form', 'param', 'window', 'popup']:
            raise InvalidXMLUI

        if self.type == 'param':
            self.param_changed = set()

        self._parseChilds(self, parsed_dom.documentElement)

        if post_treat is not None:
            post_treat()

    def _xmluiClose(self):
        """Close the window/popup/... where the constructeur XMLUI is

        this method must be overrided
        """
        raise NotImplementedError

    def _xmluiSetParam(self, name, value, category):
        self.host.bridge.setParam(name, value, category, profile_key=self.host.profile)

    ##EVENTS##

    def onParamChange(self, ctrl):
        """Called when type is param and a widget to save is modified

        @param ctrl: widget modified
        """
        assert(self.type == "param")
        self.param_changed.add(ctrl)

    def onAdvListSelect(self, ctrl):
        data = {}
        widgets = ctrl._xmluiGetSelectedWidgets()
        for wid in widgets:
            try:
                name = self.escape(wid._xmlui_name)
                value = wid._xmluiGetValue()
                data[name] = value
            except (AttributeError, TypeError): # XXX: TypeError is here because pyjamas raise a TypeError instead of an AttributeError
                pass
        idx = ctrl._xmluiGetSelectedIndex()
        if idx is not None:
            data['index'] = idx
        callback_id = ctrl._xmlui_callback_id
        if callback_id is None:
            log.info(_("No callback_id found"))
            return
        self._xmluiLaunchAction(callback_id, data)

    def onButtonPress(self, button):
        """Called when an XMLUI button is clicked

        Launch the action associated to the button
        @param button: the button clicked
        """
        callback_id, fields = button._xmlui_param_id
        if not callback_id:  # the button is probably bound to an internal action
            return
        data = {}
        for field in fields:
            escaped = self.escape(field)
            ctrl = self.ctrl_list[field]
            if isinstance(ctrl['control'], ListWidget):
                data[escaped] = u'\t'.join(ctrl['control']._xmluiGetSelectedValues())
            else:
                data[escaped] = ctrl['control']._xmluiGetValue()
        self._xmluiLaunchAction(callback_id, data)

    def onChangeInternal(self, ctrl):
        """Called when a widget that has been bound to an internal callback is changed.

        This is used to perform some UI actions without communicating with the backend.
        See sat.tools.xml_tools.Widget.setInternalCallback for more details.
        @param ctrl: widget modified
        """
        action, fields, data = ctrl._xmlui_param_internal
        if action not in ('copy', 'move', 'groups_of_contact'):
            raise NotImplementedError(_("FIXME: XMLUI internal action [%s] is not implemented") % action)

        def copy_move(source, target):
            """Depending of 'action' value, copy or move from source to target."""
            if isinstance(target, ListWidget):
                if isinstance(source, ListWidget):
                    values = source._xmluiGetSelectedValues()
                else:
                    values = [source._xmluiGetValue()]
                    if action == 'move':
                        source._xmluiSetValue('')
                values = [value for value in values if value]
                if values:
                    target._xmluiAddValues(values, select=True)
            else:
                if isinstance(source, ListWidget):
                    value = u', '.join(source._xmluiGetSelectedValues())
                else:
                    value = source._xmluiGetValue()
                    if action == 'move':
                        source._xmluiSetValue('')
                target._xmluiSetValue(value)

        def groups_of_contact(source, target):
            """Select in target the groups of the contact which is selected in source."""
            assert(isinstance(source, ListWidget))
            assert(isinstance(target, ListWidget))
            try:
                contact_jid_s = source._xmluiGetSelectedValues()[0]
            except IndexError:
                return
            target._xmluiSelectValues(data[contact_jid_s])
            pass

        source = None
        for field in fields:
            widget = self.ctrl_list[field]['control']
            if not source:
                source = widget
                continue
            if action in ('copy', 'move'):
                copy_move(source, widget)
            elif action == 'groups_of_contact':
                groups_of_contact(source, widget)
            source = None

    def getInternalCallbackData(self, action, node):
        """Retrieve from node the data needed to perform given action.

        @param action (string): a value from the one that can be passed to the
            'callback' parameter of sat.tools.xml_tools.Widget.setInternalCallback
        @param node (DOM Element): the node of the widget that triggers the callback
        """
        # TODO: it would be better to not have a specific way to retrieve
        # data for each action, but instead to have a generic method to
        # extract any kind of data structure from the 'internal_data' element.

        try:  # data is stored in the first 'internal_data' element of the node
            data_elts = node.getElementsByTagName('internal_data')[0].childNodes
        except IndexError:
            return None
        data = {}
        if action == 'groups_of_contact':  # return a dict(key: string, value: list[string])
            for elt in data_elts:
                jid_s = elt.getAttribute('name')
                data[jid_s] = []
                for value_elt in elt.childNodes:
                    data[jid_s].append(value_elt.getAttribute('name'))
        return data

    def onFormSubmitted(self, ignore=None):
        """An XMLUI form has been submited

        call the submit action associated with this form
        """
        selected_values = []
        for ctrl_name in self.ctrl_list:
            escaped = self.escape(ctrl_name)
            ctrl = self.ctrl_list[ctrl_name]
            if isinstance(ctrl['control'], ListWidget):
                selected_values.append((escaped, u'\t'.join(ctrl['control']._xmluiGetSelectedValues())))
            else:
                selected_values.append((escaped, ctrl['control']._xmluiGetValue()))
        if self.submit_id is not None:
            data = dict(selected_values)
            self.submit(data)
        else:
            log.warning(_("The form data is not sent back, the type is not managed properly"))
        self._xmluiClose()

    def onFormCancelled(self, ignore=None):
        """Called when a form is cancelled"""
        log.debug(_("Cancelling form"))
        self._xmluiClose()

    def onSaveParams(self, ignore=None):
        """Params are saved, we send them to backend

        self.type must be param
        """
        assert(self.type == 'param')
        for ctrl in self.param_changed:
            if isinstance(ctrl, ListWidget):
                value = u'\t'.join(ctrl._xmluiGetSelectedValues())
            else:
                value = ctrl._xmluiGetValue()
            param_name = ctrl._xmlui_name.split(C.SAT_PARAM_SEPARATOR)[1]
            self._xmluiSetParam(param_name, value, ctrl._param_category)

        self._xmluiClose()

    def show(self, *args, **kwargs):
        pass


class XMLUIDialog(XMLUIBase):
    dialog_factory = None

    def __init__(self, host, parsed_dom, title = None, flags = None):
        super(XMLUIDialog, self).__init__(host, parsed_dom, title = None, flags = None)
        top=parsed_dom.documentElement
        dlg_elt =  self._getChildNode(top, "dialog")
        if dlg_elt is None:
            raise ValueError("Invalid XMLUI: no Dialog element found !")
        dlg_type = dlg_elt.getAttribute("type") or C.XMLUI_DIALOG_MESSAGE
        try:
            mess_elt = self._getChildNode(dlg_elt, C.XMLUI_DATA_MESS)
            message = getText(mess_elt)
        except (TypeError, AttributeError): # XXX: TypeError is here because pyjamas raise a TypeError instead of an AttributeError
            message = ""
        level = dlg_elt.getAttribute(C.XMLUI_DATA_LVL) or C.XMLUI_DATA_LVL_INFO

        if dlg_type == C.XMLUI_DIALOG_MESSAGE:
            self.dlg = self.dialog_factory.createMessageDialog(self, self.title, message, level)
        elif dlg_type == C.XMLUI_DIALOG_NOTE:
            self.dlg = self.dialog_factory.createNoteDialog(self, self.title, message, level)
        elif dlg_type == C.XMLUI_DIALOG_CONFIRM:
            try:
                buttons_elt = self._getChildNode(dlg_elt, "buttons")
                buttons_set = buttons_elt.getAttribute("set") or C.XMLUI_DATA_BTNS_SET_DEFAULT
            except (TypeError, AttributeError): # XXX: TypeError is here because pyjamas raise a TypeError instead of an AttributeError
                buttons_set = C.XMLUI_DATA_BTNS_SET_DEFAULT
            self.dlg = self.dialog_factory.createConfirmDialog(self, self.title, message, level, buttons_set)
        elif dlg_type == C.XMLUI_DIALOG_FILE:
            try:
                file_elt = self._getChildNode(dlg_elt, "file")
                filetype = file_elt.getAttribute("type") or C.XMLUI_DATA_FILETYPE_DEFAULT
            except (TypeError, AttributeError): # XXX: TypeError is here because pyjamas raise a TypeError instead of an AttributeError
                filetype = C.XMLUI_DATA_FILETYPE_DEFAULT
            self.dlg = self.dialog_factory.createFileDialog(self, self.title, message, level, filetype)
        else:
            raise ValueError("Unknown dialog type [%s]" % dlg_type)

    def show(self):
        self.dlg._xmluiShow()


def registerClass(type_, class_):
    """Register the class to use with the factory

    @param type_: one of:
        CLASS_PANEL: classical XMLUI interface
        CLASS_DIALOG: XMLUI dialog
    @param class_: the class to use to instanciate given type
    """
    assert type_ in (CLASS_PANEL, CLASS_DIALOG)
    class_map[type_] = class_


def create(host, xml_data, title = None, flags = None, dom_parse=None, dom_free=None):
    """
        @param dom_parse: methode equivalent to minidom.parseString (but which  must manage unicode), or None to use default one
        @param dom_free: method used to free the parsed DOM
    """
    if dom_parse is None:
        from xml.dom import minidom
        dom_parse = lambda xml_data: minidom.parseString(xml_data.encode('utf-8'))
        dom_free = lambda parsed_dom: parsed_dom.unlink()
    else:
        dom_parse = dom_parse
        dom_free = dom_free or (lambda parsed_dom: None)
    parsed_dom = dom_parse(xml_data)
    top=parsed_dom.documentElement
    ui_type = top.getAttribute("type")
    try:
        if ui_type != C.XMLUI_DIALOG:
            cls = class_map[CLASS_PANEL]
        else:
            cls = class_map[CLASS_DIALOG]
    except KeyError:
        raise ClassNotRegistedError(_("You must register classes with registerClass before creating a XMLUI"))

    xmlui = cls(host, parsed_dom, title, flags)
    dom_free(parsed_dom)
    return xmlui