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diff --git a/studio/static/doc/myosa/ch011_add-refinements.xhtml b/studio/static/doc/myosa/ch011_add-refinements.xhtml new file mode 100644 index 0000000..0cd76dd --- /dev/null +++ b/studio/static/doc/myosa/ch011_add-refinements.xhtml @@ -0,0 +1,625 @@ +<?xml version="1.0" encoding="UTF-8"?> +<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" + "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd"> +<html xmlns="http://www.w3.org/1999/xhtml"><body><h1>Add Refinements +</h1> +<h2>Toolbars +</h2> +<p>It is a truth universally acknowledged that a first rate Activity needs good Toolbars.  In this chapter we'll learn how to make them.  We're going to put the toolbar classes in a separate file from the rest, because there are two styles of toolbar (old and new) and we may want to support both in our Activity.  If we have two different files containing toolbar classes our code can decide at runtime which one it wants to use.  For now, this code supports the old style, which works with every version of Sugar.  The new style is currently only supported by <em>Sugar on a Stick. </em> +</p> +<p>There is a file called <strong>toolbar.py</strong> in the <strong>Add_Refinements</strong> directory of the Git repository that looks like this: + <br/></p> +<pre>from gettext import gettext as _ +import re + +import pango +import gobject +import gtk + +from sugar.graphics.toolbutton import ToolButton +from sugar.activity import activity + +class ReadToolbar(gtk.Toolbar): + __gtype_name__ = 'ReadToolbar' + + def __init__(self): + gtk.Toolbar.__init__(self) + + self.back = ToolButton('go-previous') + self.back.set_tooltip(_('Back')) + self.back.props.sensitive = False + self.insert(self.back, -1) + self.back.show() + + self.forward = ToolButton('go-next') + self.forward.set_tooltip(_('Forward')) + self.forward.props.sensitive = False + self.insert(self.forward, -1) + self.forward.show() + + num_page_item = gtk.ToolItem() + + self.num_page_entry = gtk.Entry() + self.num_page_entry.set_text('0') + self.num_page_entry.set_alignment(1) + self.num_page_entry.connect('insert-text', + self.num_page_entry_insert_text_cb) + + self.num_page_entry.set_width_chars(4) + + num_page_item.add(self.num_page_entry) + self.num_page_entry.show() + + self.insert(num_page_item, -1) + num_page_item.show() + + total_page_item = gtk.ToolItem() + + self.total_page_label = gtk.Label() + + label_attributes = pango.AttrList() + label_attributes.insert(pango.AttrSize( + 14000, 0, -1)) + label_attributes.insert(pango.AttrForeground( + 65535, 65535, 65535, 0, -1)) + self.total_page_label.set_attributes( + label_attributes) + + self.total_page_label.set_text(' / 0') + total_page_item.add(self.total_page_label) + self.total_page_label.show() + + self.insert(total_page_item, -1) + total_page_item.show() + + def num_page_entry_insert_text_cb(self, entry, text, + length, position): + if not re.match('[0-9]', text): + entry.emit_stop_by_name('insert-text') + return True + return False + + def update_nav_buttons(self): + current_page = self.current_page + self.back.props.sensitive = current_page > 0 + self.forward.props.sensitive = \ + current_page < self.total_pages - 1 + + self.num_page_entry.props.text = str( + current_page + 1) + self.total_page_label.props.label = \ + ' / ' + str(self.total_pages) + + def set_total_pages(self, pages): + self.total_pages = pages + + def set_current_page(self, page): + self.current_page = page + self.update_nav_buttons() + +class ViewToolbar(gtk.Toolbar): + __gtype_name__ = 'ViewToolbar' + + __gsignals__ = { + 'needs-update-size': (gobject.SIGNAL_RUN_FIRST, + gobject.TYPE_NONE, + ([])), + 'go-fullscreen': (gobject.SIGNAL_RUN_FIRST, + gobject.TYPE_NONE, + ([])) + } + + def __init__(self): + gtk.Toolbar.__init__(self) + self.zoom_out = ToolButton('zoom-out') + self.zoom_out.set_tooltip(_('Zoom out')) + self.insert(self.zoom_out, -1) + self.zoom_out.show() + + self.zoom_in = ToolButton('zoom-in') + self.zoom_in.set_tooltip(_('Zoom in')) + self.insert(self.zoom_in, -1) + self.zoom_in.show() + + spacer = gtk.SeparatorToolItem() + spacer.props.draw = False + self.insert(spacer, -1) + spacer.show() + + self.fullscreen = ToolButton('view-fullscreen') + self.fullscreen.set_tooltip(_('Fullscreen')) + self.fullscreen.connect('clicked', + self.fullscreen_cb) + self.insert(self.fullscreen, -1) + self.fullscreen.show() + + def fullscreen_cb(self, button): + self.emit('go-fullscreen') +</pre> +<p>Another file in the same directory of the Git repository is named <strong>ReadEtextsActivity2.py.</strong>  It looks like this: +</p> +<pre>import os +import zipfile +import gtk +import pango +from sugar.activity import activity +from sugar.graphics import style +from toolbar import ReadToolbar, ViewToolbar +from gettext import gettext as _ + +page=0 +PAGE_SIZE = 45 +TOOLBAR_READ = 2 + +class ReadEtextsActivity(activity.Activity): + def __init__(self, handle): + "The entry point to the Activity" + global page + activity.Activity.__init__(self, handle) + + toolbox = activity.ActivityToolbox(self) + activity_toolbar = toolbox.get_activity_toolbar() + activity_toolbar.keep.props.visible = False + activity_toolbar.share.props.visible = False + + self.edit_toolbar = activity.EditToolbar() + self.edit_toolbar.undo.props.visible = False + self.edit_toolbar.redo.props.visible = False + self.edit_toolbar.separator.props.visible = False + self.edit_toolbar.copy.set_sensitive(False) + self.edit_toolbar.copy.connect('clicked', + self.edit_toolbar_copy_cb) + self.edit_toolbar.paste.props.visible = False + toolbox.add_toolbar(_('Edit'), self.edit_toolbar) + self.edit_toolbar.show() + + self.read_toolbar = ReadToolbar() + toolbox.add_toolbar(_('Read'), self.read_toolbar) + self.read_toolbar.back.connect('clicked', + self.go_back_cb) + self.read_toolbar.forward.connect('clicked', + self.go_forward_cb) + self.read_toolbar.num_page_entry.connect('activate', + self.num_page_entry_activate_cb) + self.read_toolbar.show() + + self.view_toolbar = ViewToolbar() + toolbox.add_toolbar(_('View'), self.view_toolbar) + self.view_toolbar.connect('go-fullscreen', + self.view_toolbar_go_fullscreen_cb) + self.view_toolbar.zoom_in.connect('clicked', + self.zoom_in_cb) + self.view_toolbar.zoom_out.connect('clicked', + self.zoom_out_cb) + self.view_toolbar.show() + + self.set_toolbox(toolbox) + toolbox.show() + self.scrolled_window = gtk.ScrolledWindow() + self.scrolled_window.set_policy(gtk.POLICY_NEVER, + gtk.POLICY_AUTOMATIC) + self.scrolled_window.props.shadow_type = \ + gtk.SHADOW_NONE + + self.textview = gtk.TextView() + self.textview.set_editable(False) + self.textview.set_cursor_visible(False) + self.textview.set_left_margin(50) + self.textview.connect("key_press_event", + self.keypress_cb) + + self.scrolled_window.add(self.textview) + self.set_canvas(self.scrolled_window) + self.textview.show() + self.scrolled_window.show() + page = 0 + self.clipboard = gtk.Clipboard( + display=gtk.gdk.display_get_default(), + selection="CLIPBOARD") + self.textview.grab_focus() + self.font_desc = pango.FontDescription("sans %d" % + style.zoom(10)) + self.textview.modify_font(self.font_desc) + + buffer = self.textview.get_buffer() + self.markset_id = buffer.connect("mark-set", + self.mark_set_cb) + self.toolbox.set_current_toolbar(TOOLBAR_READ) + + def keypress_cb(self, widget, event): + "Respond when the user presses one of the arrow keys" + keyname = gtk.gdk.keyval_name(event.keyval) + print keyname + if keyname == 'plus': + self.font_increase() + return True + if keyname == 'minus': + self.font_decrease() + return True + if keyname == 'Page_Up' : + self.page_previous() + return True + if keyname == 'Page_Down': + self.page_next() + return True + if keyname == 'Up' or keyname == 'KP_Up' \ + or keyname == 'KP_Left': + self.scroll_up() + return True + if keyname == 'Down' or keyname == 'KP_Down' \ + or keyname == 'KP_Right': + self.scroll_down() + return True + return False + + def num_page_entry_activate_cb(self, entry): + global page + if entry.props.text: + new_page = int(entry.props.text) - 1 + else: + new_page = 0 + + if new_page >= self.read_toolbar.total_pages: + new_page = self.read_toolbar.total_pages - 1 + elif new_page < 0: + new_page = 0 + + self.read_toolbar.current_page = new_page + self.read_toolbar.set_current_page(new_page) + self.show_page(new_page) + entry.props.text = str(new_page + 1) + self.read_toolbar.update_nav_buttons() + page = new_page + + def go_back_cb(self, button): + self.page_previous() + + def go_forward_cb(self, button): + self.page_next() + + def page_previous(self): + global page + page=page-1 + if page < 0: page=0 + self.read_toolbar.set_current_page(page) + self.show_page(page) + v_adjustment = \ + self.scrolled_window.get_vadjustment() + v_adjustment.value = v_adjustment.upper -\ + v_adjustment.page_size + + def page_next(self): + global page + page=page+1 + if page >= len(self.page_index): page=0 + self.read_toolbar.set_current_page(page) + self.show_page(page) + v_adjustment = \ + self.scrolled_window.get_vadjustment() + v_adjustment.value = v_adjustment.lower + + def zoom_in_cb(self, button): + self.font_increase() + + def zoom_out_cb(self, button): + self.font_decrease() + + def font_decrease(self): + font_size = self.font_desc.get_size() / 1024 + font_size = font_size - 1 + if font_size < 1: + font_size = 1 + self.font_desc.set_size(font_size * 1024) + self.textview.modify_font(self.font_desc) + + def font_increase(self): + font_size = self.font_desc.get_size() / 1024 + font_size = font_size + 1 + self.font_desc.set_size(font_size * 1024) + self.textview.modify_font(self.font_desc) + + def mark_set_cb(self, textbuffer, iter, textmark): + + if textbuffer.get_has_selection(): + begin, end = textbuffer.get_selection_bounds() + self.edit_toolbar.copy.set_sensitive(True) + else: + self.edit_toolbar.copy.set_sensitive(False) + + def edit_toolbar_copy_cb(self, button): + textbuffer = self.textview.get_buffer() + begin, end = textbuffer.get_selection_bounds() + copy_text = textbuffer.get_text(begin, end) + self.clipboard.set_text(copy_text) + + def view_toolbar_go_fullscreen_cb(self, view_toolbar): + self.fullscreen() + + def scroll_down(self): + v_adjustment = \ + self.scrolled_window.get_vadjustment() + if v_adjustment.value == v_adjustment.upper - \ + v_adjustment.page_size: + self.page_next() + return + if v_adjustment.value < v_adjustment.upper - \ + v_adjustment.page_size: + new_value = v_adjustment.value + \ + v_adjustment.step_increment + if new_value > v_adjustment.upper - \ + v_adjustment.page_size: + new_value = v_adjustment.upper - \ + v_adjustment.page_size + v_adjustment.value = new_value + + def scroll_up(self): + v_adjustment = \ + self.scrolled_window.get_vadjustment() + if v_adjustment.value == v_adjustment.lower: + self.page_previous() + return + if v_adjustment.value > v_adjustment.lower: + new_value = v_adjustment.value - \ + v_adjustment.step_increment + if new_value < v_adjustment.lower: + new_value = v_adjustment.lower + v_adjustment.value = new_value + + def show_page(self, page_number): + global PAGE_SIZE, current_word + position = self.page_index[page_number] + self.etext_file.seek(position) + linecount = 0 + label_text = '\n\n\n' + textbuffer = self.textview.get_buffer() + while linecount < PAGE_SIZE: + line = self.etext_file.readline() + label_text = label_text + unicode(line, + 'iso-8859-1') + linecount = linecount + 1 + label_text = label_text + '\n\n\n' + textbuffer.set_text(label_text) + self.textview.set_buffer(textbuffer) + + def save_extracted_file(self, zipfile, filename): + "Extract the file to a temp directory for viewing" + filebytes = zipfile.read(filename) + outfn = self.make_new_filename(filename) + if (outfn == ''): + return False + f = open(os.path.join(self.get_activity_root(), + 'tmp', outfn), 'w') + try: + f.write(filebytes) + finally: + f.close() + + def get_saved_page_number(self): + global page + title = self.metadata.get('title', '') + if title == '' or not title[len(title)- 1].isdigit(): + page = 0 + else: + i = len(title) - 1 + newPage = '' + while (title[i].isdigit() and i > 0): + newPage = title[i] + newPage + i = i - 1 + if title[i] == 'P': + page = int(newPage) - 1 + else: + # not a page number; maybe a volume number. + page = 0 + + def save_page_number(self): + global page + title = self.metadata.get('title', '') + if title == '' or not title[len(title)-1].isdigit(): + title = title + ' P' + str(page + 1) + else: + i = len(title) - 1 + while (title[i].isdigit() and i > 0): + i = i - 1 + if title[i] == 'P': + title = title[0:i] + 'P' + str(page + 1) + else: + title = title + ' P' + str(page + 1) + self.metadata['title'] = title + + def read_file(self, filename): + "Read the Etext file" + global PAGE_SIZE, page + + if zipfile.is_zipfile(filename): + self.zf = zipfile.ZipFile(filename, 'r') + self.book_files = self.zf.namelist() + self.save_extracted_file(self.zf, + self.book_files[0]) + currentFileName = os.path.join( + self.get_activity_root(), + 'tmp', self.book_files[0]) + else: + currentFileName = filename + + self.etext_file = open(currentFileName,"r") + self.page_index = [ 0 ] + pagecount = 0 + linecount = 0 + while self.etext_file: + line = self.etext_file.readline() + if not line: + break + linecount = linecount + 1 + if linecount >= PAGE_SIZE: + position = self.etext_file.tell() + self.page_index.append(position) + linecount = 0 + pagecount = pagecount + 1 + if filename.endswith(".zip"): + os.remove(currentFileName) + self.get_saved_page_number() + self.show_page(page) + self.read_toolbar.set_total_pages(pagecount + 1) + self.read_toolbar.set_current_page(page) + + def make_new_filename(self, filename): + partition_tuple = filename.rpartition('/') + return partition_tuple[2] + + def write_file(self, filename): + "Save meta data for the file." + self.metadata['activity'] = self.get_bundle_id() + self.save_page_number() +</pre> +<p>This is the <strong>activity.info</strong> for this example: +</p> +<pre>[Activity] +name = Read ETexts II +service_name = net.flossmanuals.ReadEtextsActivity +icon = read-etexts +<strong>exec = sugar-activity ReadEtextsActivity2.ReadEtextsActivity</strong> +show_launcher = no +activity_version = 1 +mime_types = text/plain;application/zip +license = GPLv2+ + +</pre> +<p>The line in <strong>bold</strong> is the only one that needs changing.  When we run this new version this is what we'll see: +</p> +<p><img alt="ReadEtexts_05.jpg" src="static/ActivitiesGuideSugar-ReadEtexts_05-en.jpg" height="480" width="640"/></p> +<p>There are a few things worth pointing out in this code.  First, have a look at this import: +</p> +<pre>from gettext import gettext as _ +</pre> +<p> We'll be using the <em>gettext</em> module of Python to support translating our Activity into other languages. We'll be using it in statements like this one: +</p> +<pre> self.back.set_tooltip(_('Back'))</pre> +<p>The underscore acts the same way as the gettext function because of the way we imported gettext.  The effect of this statement will be to look in a special translation file for a word or phrase that matches the key "Back" and replace it with its translation.  If there is no translation file for the language we want then it will simply use the word "Back".  We'll explore setting up these translation files later, but for now using gettext for all of the words and phrases we will show to our Activity users lays some important groundwork. +</p> +<p>The second thing worth pointing out is that while our revised Activity has four toolbars we only had to create two of them.  The other two, <strong>Activity</strong> and <strong>Edit</strong>, are part of the Sugar Python library.  We can use those toolbars as is, hide the controls we don't need, or even extend them by adding new controls.  In the example we're hiding the <strong>Keep</strong> and <strong>Share</strong> controls of the Activity toolbar and the <strong>Undo</strong>, <strong>Redo</strong>, and <strong>Paste</strong> buttons of the Edit toolbar.  We currently do not support sharing books or modifying the text in books so these controls are not needed.  Note too that the Activity toolbar is part of the <strong>ActivityToolbox</strong>.  There is no way to give your Activity a toolbox that does not contain the Activity toolbar as its first entry. +</p> +<p>Another thing to notice is that the Activity class doesn't just provide us with a window.  The window has a VBox to hold our toolbars and the body of our Activity.  We install the toolbox using <em>set_toolbox()</em> and the body of the Activity using <em>set_canvas()</em>. +</p> +<p>The <strong>Read</strong> and <strong>View</strong> toolbars are regular PyGtk programming, but notice that there is a special button for Sugar toolbars that can have a tooltip attached to it, plus the <strong>View</strong> toolbar has code to hide the toolbox and <strong>ReadEtextsActivity2</strong> has code to unhide it.  This is an easy function to add to your own Activities and many games and other kinds of Activities can benefit from the increased screen area you get when you hide the toolbox. +</p> +<h2>Metadata And Journal Entries + <br/></h2> +<p>Every Journal entry represents a single file plus <strong>metadata</strong>, or information describing the file.  There are standard metadata entries that all Journal entries have and you can also create your own custom metadata. +</p> +<p> Unlike ReadEtextsActivity, this version has a <em>write_file()</em> method. +</p> +<pre> def write_file(self, filename): + "Save meta data for the file." + self.metadata['activity'] = self.get_bundle_id() + self.save_page_number() +</pre> +<p> We didn't have a <em>write_file()</em> method before because we weren't going to update the file the book is in, and we still aren't.  We will, however, be updating the metadata for the Journal entry.  Specifically, we'll be doing two things: +</p> +<ul><li>Save the page number our Activity user stopped reading on so when he launches the Activity again we can return to that page.</li> + <li>Tell the Journal entry that it belongs to our Activity, so that in the future it will use our Activity's icon and can launch our Activity with one click.</li> +</ul><p>The way the <strong>Read</strong> Activity saves page number is to use a custom metadata property.  +</p> +<pre> self.metadata['Read_current_page'] = \ + str(self._document.get_page_cache().get_current_page()) +</pre> +<p><strong>Read</strong> creates a custom metadata property named <em>Read_current_page </em>to store the current page number.  You can create any number of custom metadata properties just this easily, so you may wonder why we aren't doing that with <strong>Read Etexts</strong>.  Actually, the first version of <strong>Read Etexts</strong> did use a custom property, but in Sugar .82 or lower there was a bug in the Journal such that custom metadata did not survive after the computer was turned off.  As a result my Activity would remember pages numbers while the computer was running, but would forget them as soon as it was shut down.  XO laptops currently cannot upgrade to anything newer than .82, and when it is possible to upgrade it will be a big job for the schools. +</p> +<p>To get around this problem I created the following two methods: + <br/></p> +<pre> def get_saved_page_number(self): + global page + title = self.metadata.get('title', '') + if title == '' or not title[len(title)-1].isdigit(): + page = 0 + else: + i = len(title) - 1 + newPage = '' + while (title[i].isdigit() and i > 0): + newPage = title[i] + newPage + i = i - 1 + if title[i] == 'P': + page = int(newPage) - 1 + else: + # not a page number; maybe a volume number. + page = 0 + + def save_page_number(self): + global page + title = self.metadata.get('title', '') + if title == '' or not title[len(title)-1].isdigit(): + title = title + ' P' + str(page + 1) + else: + i = len(title) - 1 + while (title[i].isdigit() and i > 0): + i = i - 1 + if title[i] == 'P': + title = title[0:i] + 'P' + str(page + 1) + else: + title = title + ' P' + str(page + 1) + self.metadata['title'] = title +</pre> +<p> <em>save_page_number()</em> looks at the current title metadata and either adds a page number to the end of it or updates the page number already there.  Since title is standard metadata for all Journal entries the Journal bug does not affect it. +</p> +<p>These examples show how to read metadata too.   + <br/></p> +<pre> title = self.metadata.get('title', '') +</pre> +<p> This line of code says "Get the metadata property named <em>title</em> and put it in the variable named <em>title</em>, If there is no title property put an empty string in <em>title</em>. +</p> +<p>Generally  you will save metadata in the <em>write_file()</em> method and read it in the <em>read_file()</em> method. +</p> +<p>In a normal Activity that writes out a file in write_file() this next line would be unnecessary: +</p> +<p> +</p> +<pre> self.metadata['activity'] = self.get_bundle_id() +</pre> +<p> Any Journal entry created by an Activity will automatically have this property set. In the case of <em>Pride and Prejudice</em>, our Activity did not create it.  We are able to read it because our Activity supports its <em>MIME type</em>.  Unfortunately, that MIME type, <em>application/zip</em>, is used by other Activities.  I found it very frustrating to want to open a book in <strong>Read Etexts</strong> and accidentally have it opened in <strong>EToys</strong> instead.  This line of code solves that problem.  You only need to use <em>Start Using...</em> the first time you read a book.  After that the book will use the <strong>Read Etexts</strong> icon and can be resumed with a single click. +</p> +<p>This does not at all affect the MIME type of the Journal entry, so if you wanted to deliberately open <em>Pride and Prejudice</em> with <strong>Etoys</strong> it is still possible. +</p> +<p>Before we leave the subject of Journal metadata let's look at all the standard metadata that every Activity has.  Here is some code that creates a new Journal entry and updates a bunch of standard properties: +</p> +<pre> def create_journal_entry(self, tempfile): + journal_entry = datastore.create() + journal_title = self.selected_title + if self.selected_volume != '': + journal_title += ' ' + _('Volume') + ' ' + \ + self.selected_volume + if self.selected_author != '': + journal_title = journal_title + ', by ' + \ + self.selected_author + journal_entry.metadata['title'] = journal_title + journal_entry.metadata['title_set_by_user'] = '1' + journal_entry.metadata['keep'] = '0' + format = \ + self._books_toolbar.format_combo.props.value + if format == '.djvu': + journal_entry.metadata['mime_type'] = \ + 'image/vnd.djvu' + if format == '.pdf' or format == '_bw.pdf': + journal_entry.metadata['mime_type'] = \ + 'application/pdf' + journal_entry.metadata['buddies'] = '' + journal_entry.metadata['preview'] = '' + journal_entry.metadata['icon-color'] = \ + profile.get_color().to_string() + textbuffer = self.textview.get_buffer() + journal_entry.metadata['description'] = \ + textbuffer.get_text(textbuffer.get_start_iter(), + textbuffer.get_end_iter()) + journal_entry.file_path = tempfile + datastore.write(journal_entry) + os.remove(tempfile) + self._alert(_('Success'), self.selected_title + \ + _(' added to Journal.')) +</pre> +<p>This code is taken from an Activity I wrote that downloads books from a website and creates Journal entries for them.  The Journal entries contain a friendly title and a full description of the book. +</p> +<p>Most Activities will only deal with one Journal entry by using the <em>read_file()</em> and <em>write_file()</em> methods but you are not limited to that.  In a later chapter I'll show you how to create and delete Journal entries, how to list the contents of the Journal, and more. + <br/></p>We've covered a lot of technical information in this chapter and there's more to come, but before we get to that we need to look at some other important topics: +<ul><li>Putting your Activity in version control.  This will enable you to share your code with the world and get other people to help work on it.</li> + <li>Getting your Activity translated into other languages.</li> + <li>Distributing your finished Activity.  (Or your not quite finished but still useful Activity). + <br/></li> +</ul></body></html>
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