""" help.py: Implement the Idle help menu.
Contents are subject to revision at any time, without notice.
Help => About IDLE: diplay About Idle dialog
<to be moved here from aboutDialog.py>
Help => IDLE Help: Display help.html with proper formatting.
Doc/library/idle.rst (Sphinx)=> Doc/build/html/library/idle.html
(help.copy_strip)=> Lib/idlelib/help.html
HelpParser - Parse help.html and and render to tk Text.
HelpText - Display formatted help.html.
HelpFrame - Contain text, scrollbar, and table-of-contents.
(This will be needed for display in a future tabbed window.)
HelpWindow - Display HelpFrame in a standalone window.
copy_strip - Copy idle.html to help.html, rstripping each line.
show_idlehelp - Create HelpWindow. Called in EditorWindow.help_dialog.
"""
from html.parser import HTMLParser
from os.path import abspath, dirname, isdir, isfile, join
from tkinter import Tk, Toplevel, Frame, Text, Scrollbar, Menu, Menubutton
from tkinter import font as tkfont
from idlelib.configHandler import idleConf
use_ttk = False # until available to import
if use_ttk:
from tkinter.ttk import Menubutton
## About IDLE ##
## IDLE Help ##
class HelpParser(HTMLParser):
"""Render help.html into a text widget.
The overridden handle_xyz methods handle a subset of html tags.
The supplied text should have the needed tag configurations.
The behavior for unsupported tags, such as table, is undefined.
"""
def __init__(self, text):
HTMLParser.__init__(self, convert_charrefs=True)
self.text = text # text widget we're rendering into
self.tags = '' # current block level text tags to apply
self.chartags = '' # current character level text tags
self.show = False # used so we exclude page navigation
self.hdrlink = False # used so we don't show header links
self.level = 0 # indentation level
self.pre = False # displaying preformatted text
self.hprefix = '' # prefix such as '25.5' to strip from headings
self.nested_dl = False # if we're in a nested <dl>
self.simplelist = False # simple list (no double spacing)
self.toc = [] # pair headers with text indexes for toc
self.header = '' # text within header tags for toc
def indent(self, amt=1):
self.level += amt
self.tags = '' if self.level == 0 else 'l'+str(self.level)
def handle_starttag(self, tag, attrs):
"Handle starttags in help.html."
class_ = ''
for a, v in attrs:
if a == 'class':
class_ = v
s = ''
if tag == 'div' and class_ == 'section':
self.show = True # start of main content
elif tag == 'div' and class_ == 'sphinxsidebar':
self.show = False # end of main content
elif tag == 'p' and class_ != 'first':
s = '\n\n'
elif tag == 'span' and class_ == 'pre':
self.chartags = 'pre'
elif tag == 'span' and class_ == 'versionmodified':
self.chartags = 'em'
elif tag == 'em':
self.chartags = 'em'
elif tag in ['ul', 'ol']:
if class_.find('simple') != -1:
s = '\n'
self.simplelist = True
else:
self.simplelist = False
self.indent()
elif tag == 'dl':
if self.level > 0:
self.nested_dl = True
elif tag == 'li':
s = '\n* ' if self.simplelist else '\n\n* '
elif tag == 'dt':
s = '\n\n' if not self.nested_dl else '\n' # avoid extra line
self.nested_dl = False
elif tag == 'dd':
self.indent()
s = '\n'
elif tag == 'pre':
self.pre = True
if self.show:
self.text.insert('end', '\n\n')
self.tags = 'preblock'
elif tag == 'a' and class_ == 'headerlink':
self.hdrlink = True
elif tag == 'h1':
self.tags = tag
elif tag in ['h2', 'h3']:
if self.show:
self.header = ''
self.text.insert('end', '\n\n')
self.tags = tag
if self.show:
self.text.insert('end', s, (self.tags, self.chartags))
def handle_endtag(self, tag):
"Handle endtags in help.html."
if tag in ['h1', 'h2', 'h3']:
self.indent(0) # clear tag, reset indent
if self.show:
self.toc.append((self.header, self.text.index('insert')))
elif tag in ['span', 'em']:
self.chartags = ''
elif tag == 'a':
self.hdrlink = False
elif tag == 'pre':
self.pre = False
self.tags = ''
elif tag in ['ul', 'dd', 'ol']:
self.indent(amt=-1)
def handle_data(self, data):
"Handle date segments in help.html."
if self.show and not self.hdrlink:
d = data if self.pre else data.replace('\n', ' ')
if self.tags == 'h1':
self.hprefix = d[0:d.index(' ')]
if self.tags in ['h1', 'h2', 'h3'] and self.hprefix != '':
if d[0:len(self.hprefix)] == self.hprefix:
d = d[len(self.hprefix):].strip()
self.header += d
self.text.insert('end', d, (self.tags, self.chartags))
class HelpText(Text):
"Display help.html."
def __init__(self, parent, filename):
"Configure tags and feed file to parser."
uwide = idleConf.GetOption('main', 'EditorWindow', 'width', type='int')
uhigh = idleConf.GetOption('main', 'EditorWindow', 'height', type='int')
uhigh = 3 * uhigh // 4 # lines average 4/3 of editor line height
Text.__init__(self, parent, wrap='word', highlightthickness=0,
padx=5, borderwidth=0, width=uwide, height=uhigh)
normalfont = self.findfont(['TkDefaultFont', 'arial', 'helvetica'])
fixedfont = self.findfont(['TkFixedFont', 'monaco', 'courier'])
self['font'] = (normalfont, 12)
self.tag_configure('em', font=(normalfont, 12, 'italic'))
self.tag_configure('h1', font=(normalfont, 20, 'bold'))
self.tag_configure('h2', font=(normalfont, 18, 'bold'))
self.tag_configure('h3', font=(normalfont, 15, 'bold'))
self.tag_configure('pre', font=(fixedfont, 12), background='#f6f6ff')
self.tag_configure('preblock', font=(fixedfont, 10), lmargin1=25,
borderwidth=1, relief='solid', background='#eeffcc')
self.tag_configure('l1', lmargin1=25, lmargin2=25)
self.tag_configure('l2', lmargin1=50, lmargin2=50)
self.tag_configure('l3', lmargin1=75, lmargin2=75)
self.tag_configure('l4', lmargin1=100, lmargin2=100)
self.parser = HelpParser(self)
with open(filename, encoding='utf-8') as f:
contents = f.read()
self.parser.feed(contents)
self['state'] = 'disabled'
def findfont(self, names):
"Return name of first font family derived from names."
for name in names:
if name.lower() in (x.lower() for x in tkfont.names(root=self)):
font = tkfont.Font(name=name, exists=True, root=self)
return font.actual()['family']
elif name.lower() in (x.lower()
for x in tkfont.families(root=self)):
return name
class HelpFrame(Frame):
"Display html text, scrollbar, and toc."
def __init__(self, parent, filename):
Frame.__init__(self, parent)
text = HelpText(self, filename)
self['background'] = text['background']
scroll = Scrollbar(self, command=text.yview)
text['yscrollcommand'] = scroll.set
self.rowconfigure(0, weight=1)
self.columnconfigure(1, weight=1) # text
self.toc_menu(text).grid(column=0, row=0, sticky='nw')
text.grid(column=1, row=0, sticky='nsew')
scroll.grid(column=2, row=0, sticky='ns')
def toc_menu(self, text):
"Create table of contents as drop-down menu."
toc = Menubutton(self, text='TOC')
drop = Menu(toc, tearoff=False)
for lbl, dex in text.parser.toc:
drop.add_command(label=lbl, command=lambda dex=dex:text.yview(dex))
toc['menu'] = drop
return toc
class HelpWindow(Toplevel):
"Display frame with rendered html."
def __init__(self, parent, filename, title):
Toplevel.__init__(self, parent)
self.wm_title(title)
self.protocol("WM_DELETE_WINDOW", self.destroy)
HelpFrame(self, filename).grid(column=0, row=0, sticky='nsew')
self.grid_columnconfigure(0, weight=1)
self.grid_rowconfigure(0, weight=1)
def copy_strip():
"Copy idle.html to idlelib/help.html, stripping trailing whitespace."
src = join(abspath(dirname(dirname(dirname(__file__)))),
'Doc', 'build', 'html', 'library', 'idle.html')
dst = join(abspath(dirname(__file__)), 'help.html')
with open(src, 'rb') as inn,\
open(dst, 'wb') as out:
for line in inn:
out.write(line.rstrip() + b'\n')
print('idle.html copied to help.html')
def show_idlehelp(parent):
"Create HelpWindow; called from Idle Help event handler."
filename = join(abspath(dirname(__file__)), 'help.html')
if not isfile(filename):
# try copy_strip, present message
return
HelpWindow(parent, filename, 'IDLE Help')
if __name__ == '__main__':
from idlelib.idle_test.htest import run
run(show_idlehelp)
