Question

我正在我的项目中使用Gtk TextView / TextBuffer，用户可以通过选择正确的切换按钮来输入富文本（粗体/斜体/下划线）。

问题是，如果我将下划线或斜体Pango标志应用于TextView中的文本，则关闭斜体/下划线并输入更多内容，然后通过TextBuffer.serialize()获取带有这些标记的文本，未格式化返回文本（在TextView中明显未格式化），并在其周围带有下划线/斜体标记。

你可以在这里看到:(注意，为了便于阅读，我使用BeautifulSoup将标签简化为HTML副本，但实际的位置/类型根本没有被编辑过。）

这是代码（需要安装Python3的Gtk3和BS4）：

import gi
gi.require_version('Gtk', '3.0')
from gi.repository import Gtk, Gdk, Pango

import smtplib, mimetypes
from bs4 import BeautifulSoup

class Handler():

    def __init__(self):
        global html
        self.state = 0

    def onDeleteWindow(self, *args):
        Gtk.main_quit(*args)

    def onSendClicked(self, button):
        start, end = textBodyBuffer.get_bounds()
        self.content = textBodyBuffer.get_text(start, end, True)

        # Below is the serialization code for exporting with format tags
        format = textBodyBuffer.register_serialize_tagset() 
        exported = textBodyBuffer.serialize(textBodyBuffer, format, start, end)

        exported = exported.decode("latin-1")

        exported = exported.split('<text_view_markup>', 1)
        del exported[0]
        exported[0] = '<text_view_markup>' + str(exported[0])

        exported = exported[0].split('</tags>', 1)
        del exported[0]

        exported = exported[0].split('</text_view_markup>', 1)
        exported = str(exported[0]).replace('\n', ' ')

        soup = BeautifulSoup(exported)

        soupTags = soup.find_all('apply_tag')

        for tag in soupTags:

            if tag['name'] == 'bold':
                tag.name = 'b'
                del tag['name']
            elif tag['name'] == 'italic':
                tag.name = 'em'
                del tag['name']
            elif tag['name'] == 'underline':
                tag.name = 'u'
                del tag['name']

        print (soup)

    def bold(self, button):
        global tags_on
        name = button.get_name()
        if button.get_active():             # Button is "down"/enabled
            tags_on.append('bold')
        elif button.get_active() != True:   # Button is "up"/disabled
            del tags_on[tags_on.index('bold')]

    def italic(self, button):
        global tags_on
        name = button.get_name()
        if button.get_active():             # Button is "down"/enabled
            tags_on.append('italic')
        elif button.get_active() != True:   # Button is "up"/disabled
            del tags_on[tags_on.index('italic')]

    def underline(self, button):
        global tags_on
        name = button.get_name()
        if button.get_active():             # Button is "down"/enabled
            tags_on.append('underline')
        elif button.get_active() != True:   # Button is "up"/disabled
            del tags_on[tags_on.index('underline')]

    def alignToggled(self, radiobutton):
        pass

    def undo(self, button):
        pass

    def redo(self, button):
        pass

    def keyHandler(self, widget, event):
        global html
        if Gdk.ModifierType.CONTROL_MASK & event.state:
            if Gdk.keyval_name(event.keyval) == 'q':    # Quit the program
                w.destroy()
                Gtk.main_quit()

def get_iter_position(buffer):
    return buffer.get_iter_at_mark(buffer.get_insert())

def text_inserted(buffer, iter, char, length):

    global tags_on

    if len(tags_on) >= 0:
        iter.backward_chars(length)

        for tag in tags_on:
            w.queue_draw()
            if tag == 'bold':
                buffer.apply_tag(tag_bold, get_iter_position(buffer), iter)
            elif tag == 'italic':
                buffer.apply_tag(tag_italic, get_iter_position(buffer), iter)
            elif tag == 'underline':
                buffer.apply_tag(tag_underline, get_iter_position(buffer), iter)


if __name__ == '__main__':

    global text, html
    # Gtk tag globals
    global tag_bold, tag_italic, tag_underline, tags_on

    tags_on = []

    text = ''
    html = '<html><body><p>'

    builder = Gtk.Builder()
    builder.add_from_file('editor.glade')
    builder.connect_signals(Handler())

    buttonSend = builder.get_object('buttonSend')

    textBody = builder.get_object('textviewBody')
    textBodyBuffer = textBody.get_buffer()

    textBodyBuffer.connect_after('insert-text', text_inserted)
    tag_bold = textBodyBuffer.create_tag("bold", weight=Pango.Weight.BOLD)
    tag_italic = textBodyBuffer.create_tag("italic", style=Pango.Style.ITALIC)
    tag_underline = textBodyBuffer.create_tag("underline", underline=Pango.Underline.SINGLE)

    w = builder.get_object('window1')
    w.show_all()

    Gtk.main()

这是editor.glade文件：

<?xml version="1.0" encoding="UTF-8"?>
<!-- Generated with glade 3.16.1 -->
<interface>
  <requires lib="gtk+" version="3.10"/>
  <object class="GtkImage" id="image1">
    <property name="visible">True</property>
    <property name="can_focus">False</property>
    <property name="icon_name">mail-send</property>
  </object>
  <object class="GtkWindow" id="window1">
    <property name="can_focus">False</property>
    <property name="title" translatable="yes">Keyboard Mail - Edit Message</property>
    <property name="modal">True</property>
    <property name="type_hint">dialog</property>
    <signal name="delete-event" handler="onDeleteWindow" swapped="no"/>
    <signal name="key-press-event" handler="keyHandler" swapped="no"/>
    <child>
      <object class="GtkBox" id="box2">
        <property name="visible">True</property>
        <property name="can_focus">False</property>
        <property name="orientation">vertical</property>
        <child>
          <object class="GtkBox" id="box1">
            <property name="visible">True</property>
            <property name="can_focus">False</property>
            <property name="orientation">vertical</property>
            <child>
              <object class="GtkButton" id="buttonSend">
                <property name="label" translatable="yes">Send</property>
                <property name="visible">True</property>
                <property name="can_focus">True</property>
                <property name="receives_default">True</property>
                <property name="image">image1</property>
                <property name="relief">none</property>
                <property name="image_position">top</property>
                <property name="always_show_image">True</property>
                <signal name="clicked" handler="onSendClicked" swapped="no"/>
              </object>
              <packing>
                <property name="expand">False</property>
                <property name="fill">False</property>
                <property name="position">1</property>
              </packing>
            </child>
          </object>
          <packing>
            <property name="expand">False</property>
            <property name="fill">False</property>
            <property name="position">1</property>
          </packing>
        </child>
        <child>
          <object class="GtkToolbar" id="toolbar1">
            <property name="visible">True</property>
            <property name="can_focus">False</property>
            <property name="toolbar_style">icons</property>
            <property name="show_arrow">False</property>
            <child>
              <object class="GtkToggleToolButton" id="buttonBold">
                <property name="name">bold</property>
                <property name="visible">True</property>
                <property name="can_focus">False</property>
                <property name="tooltip_text" translatable="yes">Make the selected text bold</property>
                <property name="icon_name">format-text-bold</property>
                <signal name="toggled" handler="bold" swapped="no"/>
              </object>
              <packing>
                <property name="expand">False</property>
                <property name="homogeneous">True</property>
              </packing>
            </child>
            <child>
              <object class="GtkToggleToolButton" id="buttonItalic">
                <property name="name">italic</property>
                <property name="visible">True</property>
                <property name="can_focus">False</property>
                <property name="icon_name">format-text-italic</property>
                <signal name="toggled" handler="italic" swapped="no"/>
              </object>
              <packing>
                <property name="expand">False</property>
                <property name="homogeneous">True</property>
              </packing>
            </child>
            <child>
              <object class="GtkToggleToolButton" id="buttonUnderline">
                <property name="name">underline</property>
                <property name="visible">True</property>
                <property name="can_focus">False</property>
                <property name="icon_name">format-text-underline</property>
                <signal name="toggled" handler="underline" swapped="no"/>
              </object>
              <packing>
                <property name="expand">False</property>
                <property name="homogeneous">True</property>
              </packing>
            </child>
          </object>
          <packing>
            <property name="expand">False</property>
            <property name="fill">True</property>
            <property name="position">3</property>
          </packing>
        </child>
        <child>
          <object class="GtkBox" id="box5">
            <property name="visible">True</property>
            <property name="can_focus">False</property>
            <property name="orientation">vertical</property>
            <child>
              <object class="GtkTextView" id="textviewBody">
                <property name="width_request">500</property>
                <property name="height_request">100</property>
                <property name="visible">True</property>
                <property name="can_focus">True</property>
                <property name="hexpand">True</property>
                <property name="vexpand">True</property>
                <property name="wrap_mode">word</property>
                <property name="left_margin">5</property>
                <property name="right_margin">5</property>
              </object>
              <packing>
                <property name="expand">True</property>
                <property name="fill">True</property>
                <property name="position">0</property>
              </packing>
            </child>
          </object>
          <packing>
            <property name="expand">False</property>
            <property name="fill">True</property>
            <property name="position">3</property>
          </packing>
        </child>
      </object>
    </child>
  </object>
</interface>

有谁知道为什么TextBuffer.serialize()语句（第23行）会在下划线/斜体标签中返回明显不带格式的字符？

我似乎无法在发生这种情况时找到任何模式，似乎随机决定是否使用标签返回文本。

编辑：我已经使用pdb（Python调试器）逐步完成了代码，但仍然没有看到任何会导致此问题的内容。

编辑：有趣的模式我已经想到了 - 如果你同时打开斜体和下划线，然后键入一些，然后立即关闭它们，然后输入{{1} } call返回正确的字符串。

但是，如果您一次应用一个，为每个新标记键入一个位，则返回错误。

Answer 1

我已经能够在C中用minimal example重新创建问题。因此我强烈怀疑这是GTK中的一个错误。提问者因此opened a bugreport upstream。

作为一种解决方法，我建议您尝试自行实现序列化。 forward_to_tag_toggle应该对此有所帮助。请注意，您不能使用明显的路径使用register_serialize_format注册自己的序列化程序然后调用serialize，因为GtkTextBufferSerializeFunc应该在GObject存储库it is apparently recorded as a function returning a single integer中返回一个字符串。（由于另一个错误。）相反，完全从您的代码执行序列化，即抓住启动它然后遍历文本缓冲区。

Gtk3 TextBuffer.serialize（）返回带有格式标签的文本，即使视觉上没有

1 个答案: