About Minibar

Some implementation details:

• It is implemented directly in JavaScipt. It does not use Google Web Toolkit or any big JavaScript libraries.
• It has been tested and found to work in the following browsers:
  • On the Mac: Firefox 3.5 & 3.6, Safari 4.0, Opera 10.10 and Google Chrome 4.0.249.49.
  • On Linux: Firefox 3.0.18 & 3.5, Opera 10.10.
  • On the Android Dev Phone: Android Mobile Safari 3.0.4 & 3.1.2 and Android Opera Mini 4.2.
  It does not seem work in Internet Explorer 7 (there are both styling and scripting issues). There seems to be some rendering bugs in Chrome 5.0.342.9 β.
• The implementation consist of two JavaScript files: minibar.js and support.js The latter is also used in a couple of small web apps based on the SALDO web services.
• To access the GF web service, it uses the JSONP method mentioned in the GF web services paper, which allows the web app to be hosted on a different server from the GF web service. (To demonstrate this, I put the Minibar demo on www.cs.chalmers.se, while the GF server that it calls is on www.grammaticalframework.org.)
• As an experiment, it does no use the grammars.xml file, but instead calls a little CGI script, grammars.cgi which lists the .pgf files in the directory, in JSONP format. (Note: if you want to install this on your own computer,
  • if you click on the link, the CGI script will be downloaded as grammars.cgi.txt, but it should be called grammars.cgi and stored on the server in the same directory as the grammar files.
  • for CGI scripts to work with lighttpd, "mod_cgi" needs to be included in the definition of server.modules in the lighttpd.conf file.)
• [Added 2010-02-16] There is a button for generating random sentences.
• [Added 2010-02-23] All translations are shown, not just the first one, if there are multiple parses.
• [Added 2010-02-25] Next to each translation, there is now a little tree icon that you can click on to see a drawing of an abstract syntax tree or a parse tree. If you click on a drawing it collapses back into a tree icon.
• [Added 2010-04-09] Preparations to support different ways to access the grammar: currently we access a PGF server via JSONP, but I would also like to support AJAX, and local/downloaded JavaScript grammars.
• [Added 2010-04-19] A text entry field appears when you click in the sentence area (with a dashed border). This allows you to enter words by typing on the keyboard. As you start typing word magnets that don't match what you are typing are removed. When only one magnet remains, you can press enter to complete the word.
• [Added 2010-04-19] There is a menu for choosing the output language: you can pick "All" to translate to all available languages, or pick one particular language.
• [Added 2010-04-19] You can pass options to the function start_minibar to customize the user interface. The default is {show_abstract:true,show_trees:true} to show the abstract syntax of parsed sentences, and to show icons that expand to syntax/parse trees next each translation. These features can be turned off by setting the fields to false.
• [Added 2010-04-30] The grammar menu is omitted if there is only one grammar in the grammar list.
• [Added 2010-04-30] Fewer hardwired constants and new start_minibar options (server, grammars_url, grammar_list, show_grouped_translations, delete_button_text) to make minibar.js more resuable.)
• [Added 2010-05-26] The magnets are now created with <input type=button> tags to make them clickable in more browsers.
• [Added 2010-05-26] The text entry field is now visible from the start, and it is removed when no more words can be added to the sentence. When you press enter, a word is added if there is only one magnet left, or if what you have entered exactly matches one of the remaining magnet.
• [Added 2010-05-28] Added a link to make it easy to try the same sentence in Google Translate.This can be turned off by passing the option {try_google:false} to start_minibar.
• [Added 2010-06-02] Added support for Help and Feedback buttons, controlled by the options feedback_url and help_url passed to start_minibar.
• [Added 2010-06-02] New option: default_source_language.
• [Added 2010-09-10] Minibar now automatically uses XHR instead of JSONP when possible (i.e. when the HTML document and the PGF service are on the same server).
• [Added 2010-09-10] The default input language is now the user's preferred language, if possible. This is implemented by consulting the userLanguage field in the grammar info output by pgf-server.
• [Added 2010-10-27] Keyboard input and completion should now work much more smoothly:
  • When you press space, the current word will be completed (if incomplete) and a new magnet will be created. If there is more than one possible completion, no magnet is created, but the common prefix of the possible completions is added to the text box.
  • Instead of asking the server for possible completions every time a new letter is added to the curent word, minibar only ask for completions for whole words and then filters the list locally when more letters are entered, speeding things up when server responses are slow.
• [Added 2010-10-27] Code restructuring:
  • The PGF server API has been moved to its own file: pgf_online.js. This allows it to be reused in other applicaitons without importing the entire minibar. It also allows minibar to be used with different server interfaces. minibar.html has been updated to show how you use the new minibar.js and pgf_online.js.
  • The minibar code has been rewritten to avoid storing state information in the document tree and accessing it by referring to named document elements. The code now also avoids using string literals containing the names of top-level functions to specify event handlers for buttons and menus. (The code is no longer introspective, so α conversion will not change its meaning.)
• [Added 2010-11-09] Some new documentation:
  • gf-web-api-examples.html: examples illustrating the PGF server API provided by pgf_online.js.
  • example.html: a minimal example of a web page that uses pgf_online.js to talk to the PGF server.
• [Added 2011-03-03] Added a button to display word alignment.
• [Changed 2011-03-22] Don't force focus to the typed input field after every word. On touch-based devices, the on-screen keyboard kept popping up after every word, which was very annoying if you were entering a sentence by tapping on the magnets.
• [Changed 2011-08-03] Moved the initialization code in minibar.html to minibar_online.js.
• [Changed 2011-08-08] For improved modularity and reusability, two smaller objects have been factored out from the Minibar object: Input and Translations. These have been placed in two separate files: minibar_input.js and minibar_translations.js. Some common auxiliary functions have also been moved to a separate file: minibar_support.js.
• [Added 2011-08-09] Added some Minibar API documentation.
• [Changed 2011-08-22] Quick fix to allow literals to be entered: if you press Enter, the current word will be accepted, even if there are no matching completions. (You can now use names of people when constructing sentences in the Letter grammar, for example.)

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