Python Qt.QEventLoop類代碼示例

def render_html(path_to_html, width=590, height=750, as_xhtml=True):
    from PyQt4.QtWebKit import QWebPage
    from PyQt4.Qt import QEventLoop, QPalette, Qt, QUrl, QSize
    from calibre.gui2 import is_ok_to_use_qt
    if not is_ok_to_use_qt(): return None
    path_to_html = os.path.abspath(path_to_html)
    with CurrentDir(os.path.dirname(path_to_html)):
        page = QWebPage()
        pal = page.palette()
        pal.setBrush(QPalette.Background, Qt.white)
        page.setPalette(pal)
        page.setViewportSize(QSize(width, height))
        page.mainFrame().setScrollBarPolicy(Qt.Vertical, Qt.ScrollBarAlwaysOff)
        page.mainFrame().setScrollBarPolicy(Qt.Horizontal, Qt.ScrollBarAlwaysOff)
        loop = QEventLoop()
        renderer = HTMLRenderer(page, loop)
        page.loadFinished.connect(renderer, type=Qt.QueuedConnection)
        if as_xhtml:
            page.mainFrame().setContent(open(path_to_html, 'rb').read(),
                    'application/xhtml+xml', QUrl.fromLocalFile(path_to_html))
        else:
            page.mainFrame().load(QUrl.fromLocalFile(path_to_html))
        loop.exec_()
    renderer.loop = renderer.page = None
    page.loadFinished.disconnect()
    del page
    del loop
    if isinstance(renderer.exception, ParserError) and as_xhtml:
        return render_html(path_to_html, width=width, height=height,
                as_xhtml=False)
    return renderer

 def _wait_for_replies(self, reply_count, timeout):
     final_time = time.time() + (self.default_timeout if timeout is default_timeout else timeout)
     loop = QEventLoop(self)
     while time.time() < final_time and self.nam.reply_count < reply_count:
         loop.processEvents()
         time.sleep(0.1)
     if self.nam.reply_count < reply_count:
         raise Timeout("Waiting for replies took longer than %d seconds" % timeout)

 def _wait_for_replies(self, reply_count, timeout):
     final_time = time.time() + timeout
     loop = QEventLoop(self)
     while (time.time() < final_time and self.nam.reply_count <
             reply_count):
         loop.processEvents()
         time.sleep(0.1)
     if self.nam.reply_count < reply_count:
         raise Timeout('Waiting for replies took longer than %d seconds' %
                 timeout)

    def download_file(self, url_or_selector_or_qwe, timeout=60):
        """
        Download unsupported content: i.e. files the browser cannot handle
        itself or files marked for saving as files by the website. Useful if
        you want to download something like an epub file after authentication.

        You can pass in either the url to the file to be downloaded, or a
        selector that points to an element to be clicked on the current page
        which will cause the file to be downloaded.
        """
        ans = [False, None, []]
        loop = QEventLoop(self)
        start_time = time.time()
        end_time = start_time + timeout
        self.page.unsupportedContent.disconnect(self.page.on_unsupported_content)
        try:

            def download(reply):
                if ans[0]:
                    reply.abort()  # We only handle the first unsupported download
                    return
                ans[0] = True
                while not reply.isFinished() and end_time > time.time():
                    if not loop.processEvents():
                        time.sleep(0.01)
                    raw = bytes(bytearray(reply.readAll()))
                    if raw:
                        ans[-1].append(raw)
                if not reply.isFinished():
                    ans[1] = Timeout("Loading of %r took longer than %d seconds" % (url_or_selector_or_qwe, timeout))
                ans[-1].append(bytes(bytearray(reply.readAll())))

            self.page.unsupportedContent.connect(download)
            if hasattr(url_or_selector_or_qwe, "rstrip") and re.match("[a-z]+://", url_or_selector_or_qwe) is not None:
                # We have a URL
                self.page.mainFrame().load(QUrl(url_or_selector_or_qwe))
            else:
                self.click(url_or_selector_or_qwe, wait_for_load=False)
            lw = LoadWatcher(self.page)
            while not ans[0] and lw.is_loading and end_time > time.time():
                if not loop.processEvents():
                    time.sleep(0.01)
            if not ans[0]:
                raise NotAFile(
                    "%r does not point to a downloadable file. You can only"
                    " use this method to download files that the browser cannot handle"
                    " natively. Or files that are marked with the "
                    " content-disposition: attachment header" % url_or_selector_or_qwe
                )
            if ans[1] is not None:
                raise ans[1]
            return b"".join(ans[-1])
        finally:
            self.page.unsupportedContent.disconnect()
            self.page.unsupportedContent.connect(self.page.on_unsupported_content)

    def _wait_for_load(self, timeout, url=None):
        timeout = self.default_timeout if timeout is default_timeout else timeout
        loop = QEventLoop(self)
        start_time = time.time()
        end_time = start_time + timeout
        lw = LoadWatcher(self.page, parent=self)
        while lw.is_loading and end_time > time.time():
            if not loop.processEvents():
                time.sleep(0.01)
        if lw.is_loading:
            raise Timeout("Loading of %r took longer than %d seconds" % (url, timeout))

        return lw.loaded_ok

    def __init__(self, opts, log, cover_data=None, toc=None):
        from calibre.gui2 import is_ok_to_use_qt
        from calibre.utils.podofo import get_podofo

        if not is_ok_to_use_qt():
            raise Exception("Not OK to use Qt")
        QObject.__init__(self)

        self.logger = self.log = log
        self.podofo = get_podofo()
        self.doc = self.podofo.PDFDoc()

        self.loop = QEventLoop()
        self.view = QWebView()
        self.page = Page(opts, self.log)
        self.view.setPage(self.page)
        self.view.setRenderHints(QPainter.Antialiasing | QPainter.TextAntialiasing | QPainter.SmoothPixmapTransform)
        self.view.loadFinished.connect(self._render_html, type=Qt.QueuedConnection)
        for x in (Qt.Horizontal, Qt.Vertical):
            self.view.page().mainFrame().setScrollBarPolicy(x, Qt.ScrollBarAlwaysOff)
        self.render_queue = []
        self.combine_queue = []
        self.tmp_path = PersistentTemporaryDirectory(u"_pdf_output_parts")

        self.opts = opts
        self.cover_data = cover_data
        self.paged_js = None
        self.toc = toc

    def __init__(self, opts, log, cover_data=None, toc=None):
        from calibre.gui2 import is_ok_to_use_qt
        if not is_ok_to_use_qt():
            raise Exception('Not OK to use Qt')
        QObject.__init__(self)

        self.logger = self.log = log
        self.opts = opts
        self.cover_data = cover_data
        self.paged_js = None
        self.toc = toc

        self.loop = QEventLoop()
        self.view = QWebView()
        self.page = Page(opts, self.log)
        self.view.setPage(self.page)
        self.view.setRenderHints(QPainter.Antialiasing|
                    QPainter.TextAntialiasing|QPainter.SmoothPixmapTransform)
        self.view.loadFinished.connect(self.render_html,
                type=Qt.QueuedConnection)
        for x in (Qt.Horizontal, Qt.Vertical):
            self.view.page().mainFrame().setScrollBarPolicy(x,
                    Qt.ScrollBarAlwaysOff)
        self.report_progress = lambda x, y: x
        self.current_section = ''

    def __init__(self, container, do_embed=False):
        self.container = container
        self.log = self.logger = container.log
        self.do_embed = do_embed
        must_use_qt()
        self.parser = CSSParser(loglevel=logging.CRITICAL, log=logging.getLogger('calibre.css'))

        self.loop = QEventLoop()
        self.view = QWebView()
        self.page = Page(self.log)
        self.view.setPage(self.page)
        self.page.setViewportSize(QSize(1200, 1600))

        self.view.loadFinished.connect(self.collect,
                type=Qt.QueuedConnection)

        self.render_queue = list(container.spine_items)
        self.font_stats = {}
        self.font_usage_map = {}
        self.font_spec_map = {}
        self.font_rule_map = {}
        self.all_font_rules = {}

        QTimer.singleShot(0, self.render_book)

        if self.loop.exec_() == 1:
            raise Exception('Failed to gather statistics from book, see log for details')

    def do_print(self, printer):
        painter = QPainter(printer)
        zoomx = printer.logicalDpiX()/self.view.logicalDpiX()
        zoomy = printer.logicalDpiY()/self.view.logicalDpiY()
        painter.scale(zoomx, zoomy)
        pr = printer.pageRect()
        self.view.page().setViewportSize(QSize(pr.width()/zoomx,
            pr.height()/zoomy))
        evaljs = self.mf.evaluateJavaScript
        loop = QEventLoop(self)
        pagenum = 0
        from_, to = printer.fromPage(), printer.toPage()
        first = True

        for path in self.iterator.spine:
            self.loaded_ok = None
            load_html(path, self.view, codec=getattr(path, 'encoding', 'utf-8'),
                    mime_type=getattr(path, 'mime_type', None))
            while self.loaded_ok is None:
                loop.processEvents(loop.ExcludeUserInputEvents)
            if not self.loaded_ok:
                return error_dialog(self.parent(), _('Failed to render'),
                        _('Failed to render document %s')%path, show=True)
            evaljs(self.paged_js)
            evaljs('''
                document.body.style.backgroundColor = "white";
                paged_display.set_geometry(1, 0, 0, 0);
                paged_display.layout();
                paged_display.fit_images();
            ''')

            while True:
                pagenum += 1
                if (pagenum >= from_ and (to == 0 or pagenum <= to)):
                    if not first:
                        printer.newPage()
                    first = False
                    self.mf.render(painter)
                nsl = evaljs('paged_display.next_screen_location()').toInt()
                if not nsl[1] or nsl[0] <= 0: break
                evaljs('window.scrollTo(%d, 0)'%nsl[0])

        painter.end()

    def __init__(self, container):
        self.container = container
        self.log = self.logger = container.log
        must_use_qt()

        self.loop = QEventLoop()
        self.view = QWebView()
        self.page = Page(self.log)
        self.view.setPage(self.page)
        self.page.setViewportSize(QSize(1200, 1600))

        self.view.loadFinished.connect(self.collect,
                type=Qt.QueuedConnection)

        self.render_queue = list(container.spine_items)
        self.font_stats = {}

        QTimer.singleShot(0, self.render_book)

        if self.loop.exec_() == 1:
            raise Exception('Failed to gather statistics from book, see log for details')

class StatsCollector(object):

    def __init__(self, container, do_embed=False):
        self.container = container
        self.log = self.logger = container.log
        self.do_embed = do_embed
        must_use_qt()
        self.parser = CSSParser(loglevel=logging.CRITICAL, log=logging.getLogger('calibre.css'))

        self.loop = QEventLoop()
        self.view = QWebView()
        self.page = Page(self.log)
        self.view.setPage(self.page)
        self.page.setViewportSize(QSize(1200, 1600))

        self.view.loadFinished.connect(self.collect,
                type=Qt.QueuedConnection)

        self.render_queue = list(container.spine_items)
        self.font_stats = {}
        self.font_usage_map = {}
        self.font_spec_map = {}
        self.font_rule_map = {}
        self.all_font_rules = {}

        QTimer.singleShot(0, self.render_book)

        if self.loop.exec_() == 1:
            raise Exception('Failed to gather statistics from book, see log for details')

    def render_book(self):
        try:
            if not self.render_queue:
                self.loop.exit()
            else:
                self.render_next()
        except:
            self.logger.exception('Rendering failed')
            self.loop.exit(1)

    def render_next(self):
        item = unicode(self.render_queue.pop(0))
        self.current_item = item
        load_html(item, self.view)

    def collect(self, ok):
        if not ok:
            self.log.error('Failed to render document: %s'%self.container.relpath(self.current_item))
            self.loop.exit(1)
            return
        try:
            self.page.load_js()
            self.collect_font_stats()
        except:
            self.log.exception('Failed to collect font stats from: %s'%self.container.relpath(self.current_item))
            self.loop.exit(1)
            return

        self.render_book()

    def href_to_name(self, href, warn_name):
        if not href.startswith('file://'):
            self.log.warn('Non-local URI in', warn_name, ':', href, 'ignoring')
            return None
        src = href[len('file://'):]
        if iswindows and len(src) > 2 and (src[0], src[2]) == ('/', ':'):
            src = src[1:]
        src = src.replace('/', os.sep)
        src = unquote(src)
        name = self.container.abspath_to_name(src)
        if not self.container.has_name(name):
            self.log.warn('Missing resource', href, 'in', warn_name,
                          'ignoring')
            return None
        return name

    def collect_font_stats(self):
        self.page.evaljs('window.font_stats.get_font_face_rules()')
        font_face_rules = self.page.bridge_value
        if not isinstance(font_face_rules, list):
            raise Exception('Unknown error occurred while reading font-face rules')

        # Weed out invalid font-face rules
        rules = []
        for rule in font_face_rules:
            ff = rule.get('font-family', None)
            if not ff:
                continue
            style = self.parser.parseStyle('font-family:%s'%ff, validate=False)
            ff = [x.value for x in
                  style.getProperty('font-family').propertyValue]
            if not ff or ff[0] == 'inherit':
                continue
            rule['font-family'] = frozenset(icu_lower(f) for f in ff)
            src = rule.get('src', None)
            if not src:
                continue
            if src.startswith('url(') and src.endswith(')') and src[4] not in {'"', "'"}:
                # Quote the url otherwise cssutils fails to parse it if it has
                # ' or " in it
#.........這裏部分代碼省略.........

class PDFWriter(QObject):  # {{{
    def __init__(self, opts, log, cover_data=None, toc=None):
        from calibre.gui2 import is_ok_to_use_qt
        from calibre.utils.podofo import get_podofo

        if not is_ok_to_use_qt():
            raise Exception("Not OK to use Qt")
        QObject.__init__(self)

        self.logger = self.log = log
        self.podofo = get_podofo()
        self.doc = self.podofo.PDFDoc()

        self.loop = QEventLoop()
        self.view = QWebView()
        self.page = Page(opts, self.log)
        self.view.setPage(self.page)
        self.view.setRenderHints(QPainter.Antialiasing | QPainter.TextAntialiasing | QPainter.SmoothPixmapTransform)
        self.view.loadFinished.connect(self._render_html, type=Qt.QueuedConnection)
        for x in (Qt.Horizontal, Qt.Vertical):
            self.view.page().mainFrame().setScrollBarPolicy(x, Qt.ScrollBarAlwaysOff)
        self.render_queue = []
        self.combine_queue = []
        self.tmp_path = PersistentTemporaryDirectory(u"_pdf_output_parts")

        self.opts = opts
        self.cover_data = cover_data
        self.paged_js = None
        self.toc = toc

    def dump(self, items, out_stream, pdf_metadata):
        self.metadata = pdf_metadata
        self._delete_tmpdir()
        self.outline = Outline(self.toc, items)

        self.render_queue = items
        self.combine_queue = []
        self.out_stream = out_stream
        self.insert_cover()

        self.render_succeeded = False
        self.current_page_num = self.doc.page_count()
        self.combine_queue.append(os.path.join(self.tmp_path, "qprinter_out.pdf"))
        self.first_page = True
        self.setup_printer(self.combine_queue[-1])
        QTimer.singleShot(0, self._render_book)
        self.loop.exec_()
        if self.painter is not None:
            self.painter.end()
        if self.printer is not None:
            self.printer.abort()

        if not self.render_succeeded:
            raise Exception("Rendering HTML to PDF failed")

    def _render_book(self):
        try:
            if len(self.render_queue) == 0:
                self._write()
            else:
                self._render_next()
        except:
            self.logger.exception("Rendering failed")
            self.loop.exit(1)

    def _render_next(self):
        item = unicode(self.render_queue.pop(0))

        self.logger.debug("Processing %s..." % item)
        self.current_item = item
        load_html(item, self.view)

    def _render_html(self, ok):
        if ok:
            self.do_paged_render()
        else:
            # The document is so corrupt that we can't render the page.
            self.logger.error("Document cannot be rendered.")
            self.loop.exit(0)
            return
        self._render_book()

    def _pass_json_value_getter(self):
        val = json.dumps(self.bridge_value)
        return QString(val)

    def _pass_json_value_setter(self, value):
        self.bridge_value = json.loads(unicode(value))

    _pass_json_value = pyqtProperty(QString, fget=_pass_json_value_getter, fset=_pass_json_value_setter)

    def setup_printer(self, outpath):
        self.printer = self.painter = None
        printer = get_pdf_printer(self.opts, output_file_name=outpath)
        painter = QPainter(printer)
        zoomx = printer.logicalDpiX() / self.view.logicalDpiX()
        zoomy = printer.logicalDpiY() / self.view.logicalDpiY()
        painter.scale(zoomx, zoomy)
        pr = printer.pageRect()
        self.printer, self.painter = printer, painter
#.........這裏部分代碼省略.........

class StatsCollector(object):
    def __init__(self, container, do_embed=False):
        self.container = container
        self.log = self.logger = container.log
        self.do_embed = do_embed
        must_use_qt()
        self.parser = CSSParser(loglevel=logging.CRITICAL, log=logging.getLogger("calibre.css"))

        self.loop = QEventLoop()
        self.view = QWebView()
        self.page = Page(self.log)
        self.view.setPage(self.page)
        self.page.setViewportSize(QSize(1200, 1600))

        self.view.loadFinished.connect(self.collect, type=Qt.QueuedConnection)

        self.render_queue = list(container.spine_items)
        self.font_stats = {}
        self.font_usage_map = {}
        self.font_spec_map = {}
        self.font_rule_map = {}
        self.all_font_rules = {}

        QTimer.singleShot(0, self.render_book)

        if self.loop.exec_() == 1:
            raise Exception("Failed to gather statistics from book, see log for details")

    def render_book(self):
        try:
            if not self.render_queue:
                self.loop.exit()
            else:
                self.render_next()
        except:
            self.logger.exception("Rendering failed")
            self.loop.exit(1)

    def render_next(self):
        item = unicode(self.render_queue.pop(0))
        self.current_item = item
        load_html(item, self.view)

    def collect(self, ok):
        if not ok:
            self.log.error("Failed to render document: %s" % self.container.relpath(self.current_item))
            self.loop.exit(1)
            return
        try:
            self.page.load_js()
            self.collect_font_stats()
        except:
            self.log.exception("Failed to collect font stats from: %s" % self.container.relpath(self.current_item))
            self.loop.exit(1)
            return

        self.render_book()

    def href_to_name(self, href, warn_name):
        if not href.startswith("file://"):
            self.log.warn("Non-local URI in", warn_name, ":", href, "ignoring")
            return None
        src = href[len("file://") :]
        if iswindows and len(src) > 2 and (src[0], src[2]) == ("/", ":"):
            src = src[1:]
        src = src.replace("/", os.sep)
        src = unquote(src)
        name = self.container.abspath_to_name(src)
        if not self.container.has_name(name):
            self.log.warn("Missing resource", href, "in", warn_name, "ignoring")
            return None
        return name

    def collect_font_stats(self):
        self.page.evaljs("window.font_stats.get_font_face_rules()")
        font_face_rules = self.page.bridge_value
        if not isinstance(font_face_rules, list):
            raise Exception("Unknown error occurred while reading font-face rules")

        # Weed out invalid font-face rules
        rules = []
        for rule in font_face_rules:
            ff = rule.get("font-family", None)
            if not ff:
                continue
            style = self.parser.parseStyle("font-family:%s" % ff, validate=False)
            ff = [x.value for x in style.getProperty("font-family").propertyValue]
            if not ff or ff[0] == "inherit":
                continue
            rule["font-family"] = frozenset(icu_lower(f) for f in ff)
            src = rule.get("src", None)
            if not src:
                continue
            style = self.parser.parseStyle("background-image:%s" % src, validate=False)
            src = style.getProperty("background-image").propertyValue[0].uri
            name = self.href_to_name(src, "@font-face rule")
            if name is None:
                continue
            rule["src"] = name
            normalize_font_properties(rule)
#.........這裏部分代碼省略.........

class StatsCollector(object):

    def __init__(self, container):
        self.container = container
        self.log = self.logger = container.log
        must_use_qt()

        self.loop = QEventLoop()
        self.view = QWebView()
        self.page = Page(self.log)
        self.view.setPage(self.page)
        self.page.setViewportSize(QSize(1200, 1600))

        self.view.loadFinished.connect(self.collect,
                type=Qt.QueuedConnection)

        self.render_queue = list(container.spine_items)
        self.font_stats = {}

        QTimer.singleShot(0, self.render_book)

        if self.loop.exec_() == 1:
            raise Exception('Failed to gather statistics from book, see log for details')

    def render_book(self):
        try:
            if not self.render_queue:
                self.loop.exit()
            else:
                self.render_next()
        except:
            self.logger.exception('Rendering failed')
            self.loop.exit(1)

    def render_next(self):
        item = unicode(self.render_queue.pop(0))
        self.current_item = item
        load_html(item, self.view)

    def collect(self, ok):
        if not ok:
            self.log.error('Failed to render document: %s'%self.container.relpath(self.current_item))
            self.loop.exit(1)
            return
        try:
            self.page.load_js()
            self.collect_font_stats()
        except:
            self.log.exception('Failed to collect font stats from: %s'%self.container.relpath(self.current_item))
            self.loop.exit(1)
            return

        self.render_book()

    def collect_font_stats(self):
        self.page.evaljs('window.font_stats.get_font_face_rules()')
        font_face_rules = self.page.bridge_value
        if not isinstance(font_face_rules, list):
            raise Exception('Unknown error occurred while reading font-face rules')

        # Weed out invalid font-face rules
        rules = []
        for rule in font_face_rules:
            ff = rule.get('font-family', None)
            if not ff: continue
            style = parseStyle('font-family:%s'%ff, validate=False)
            ff = [x.value for x in
                  style.getProperty('font-family').propertyValue]
            if not ff or ff[0] == 'inherit':
                continue
            rule['font-family'] = frozenset(icu_lower(f) for f in ff)
            src = rule.get('src', None)
            if not src: continue
            style = parseStyle('background-image:%s'%src, validate=False)
            src = style.getProperty('background-image').propertyValue[0].uri
            if not src.startswith('file://'):
                self.log.warn('Unknown URI in @font-face: %r'%src)
                continue
            src = src[len('file://'):]
            if iswindows and src.startswith('/'):
                src = src[1:]
            src = src.replace('/', os.sep)
            src = unquote(src)
            name = self.container.abspath_to_name(src)
            if not self.container.has_name(name):
                self.log.warn('Font %r referenced in @font-face rule not found'
                              %name)
                continue
            rule['src'] = name
            normalize_font_properties(rule)
            rule['width'] = widths[rule['font-stretch']]
            rule['weight'] = int(rule['font-weight'])
            rules.append(rule)

        if not rules:
            return

        for rule in rules:
            if rule['src'] not in self.font_stats:
                self.font_stats[rule['src']] = set()
#.........這裏部分代碼省略.........

class PDFWriter(QObject): # {{{

    def __init__(self, opts, log, cover_data=None):
        from calibre.gui2 import is_ok_to_use_qt
        if not is_ok_to_use_qt():
            raise Exception('Not OK to use Qt')
        QObject.__init__(self)

        self.logger = log

        self.loop = QEventLoop()
        self.view = QWebView()
        self.view.setRenderHints(QPainter.Antialiasing|QPainter.TextAntialiasing|QPainter.SmoothPixmapTransform)
        self.view.loadFinished.connect(self._render_html,
                type=Qt.QueuedConnection)
        for x in (Qt.Horizontal, Qt.Vertical):
            self.view.page().mainFrame().setScrollBarPolicy(x,
                    Qt.ScrollBarAlwaysOff)
        self.render_queue = []
        self.combine_queue = []
        self.tmp_path = PersistentTemporaryDirectory(u'_pdf_output_parts')

        self.opts = opts
        self.cover_data = cover_data
        self.paged_js = None

    def dump(self, items, out_stream, pdf_metadata):
        self.metadata = pdf_metadata
        self._delete_tmpdir()

        self.render_queue = items
        self.combine_queue = []
        self.out_stream = out_stream

        QMetaObject.invokeMethod(self, "_render_book", Qt.QueuedConnection)
        self.loop.exec_()


    @QtCore.pyqtSignature('_render_book()')
    def _render_book(self):
        if len(self.render_queue) == 0:
            self._write()
        else:
            self._render_next()

    def _render_next(self):
        item = unicode(self.render_queue.pop(0))
        self.combine_queue.append(os.path.join(self.tmp_path, '%i.pdf' % (len(self.combine_queue) + 1)))

        self.logger.debug('Processing %s...' % item)
        load_html(item, self.view)

    def _render_html(self, ok):
        if ok:
            item_path = os.path.join(self.tmp_path, '%i.pdf' % len(self.combine_queue))
            self.logger.debug('\tRendering item %s as %i.pdf' % (os.path.basename(str(self.view.url().toLocalFile())), len(self.combine_queue)))
            self.do_paged_render(item_path)
        else:
            # The document is so corrupt that we can't render the page.
            self.loop.exit(0)
            raise Exception('Document cannot be rendered.')
        self._render_book()

    def do_paged_render(self, outpath):
        from PyQt4.Qt import QSize, QPainter
        if self.paged_js is None:
            from calibre.utils.resources import compiled_coffeescript
            self.paged_js = compiled_coffeescript('ebooks.oeb.display.utils')
            self.paged_js += compiled_coffeescript('ebooks.oeb.display.paged')
        printer = get_pdf_printer(self.opts, output_file_name=outpath)
        painter = QPainter(printer)
        zoomx = printer.logicalDpiX()/self.view.logicalDpiX()
        zoomy = printer.logicalDpiY()/self.view.logicalDpiY()
        painter.scale(zoomx, zoomy)

        pr = printer.pageRect()
        evaljs = self.view.page().mainFrame().evaluateJavaScript
        evaljs(self.paged_js)
        self.view.page().setViewportSize(QSize(pr.width()/zoomx,
            pr.height()/zoomy))
        evaljs('''
        document.body.style.backgroundColor = "white";
        paged_display.set_geometry(1, 0, 0, 0);
        paged_display.layout();
        paged_display.fit_images();
        ''')
        mf = self.view.page().mainFrame()
        while True:
            mf.render(painter)
            nsl = evaljs('paged_display.next_screen_location()').toInt()
            if not nsl[1] or nsl[0] <= 0: break
            evaljs('window.scrollTo(%d, 0)'%nsl[0])
            printer.newPage()

        painter.end()
        printer.abort()

    def _delete_tmpdir(self):
        if os.path.exists(self.tmp_path):
            shutil.rmtree(self.tmp_path, True)
#.........這裏部分代碼省略.........