vietnamese-t9-ime

An old-fashioned keypad based input method (T9) for Vietnamese, support accents

The T9 input method

(From Wikipedia )

T9's objective is to make it easier to type text messages. It allows words to be entered by a single keypress for each letter, as opposed to the multi-tap approach used in conventional mobile phone text entry, in which several letters are associated with each key, and selecting one letter often requires multiple keypresses.

Specifications (Stories):

Definitions:

• Program states: These are the program states:
  1. Inputting
  2. Confirmed
• Candidates: ...
• numSeq(keySeq): number sequence: the sequence of input keys' digit/char(?). (What should we call the Star/Sharp key?)
• combination character:

Specs:

1. [ ] User should interact mainly with the keypad (other means of interacting is optionally supported). (Keypad-centric accessibility: make use all the key on the keypad, prevent actions outside of the keypad (dialpad)).
2. [ ] Uppercase should only occur at first letter of words.
3. [ ] User should be able to select from a set of displayed candidates.
4. [x] When inputting, the possible candidates should be displayed.
5. [ ] When confirm button is pressed, the selected candidate should be outputted.
   1. [ ] If no candidate is being selected then the first candidate will be used.
   2. [ ] If no candidates found, return the entered numSeq.
   3. [ ] The numSeq should be one of the candidates.
6. [ ] If dawg has been built, use that dawg to minimize app start time.
7. For Vietnamese:
   1. [ ] The output should NOT contain combining character, it should contains only rigid unicode character.

Basic Design:

The UI will follow the MVP design pattern:

• Make the Activity implement the View interface
• Presenter: Receive UI event, wiring action with the UI(View)
• Model? - Everything else?

Design philosophy:

This project honor 7 virtues of good object by yegor256.

Things to consider

• [x] Which standard to decompose vietnamese (syllable=ascii+accents)
  • http://www.unicode.org/reports/tr15/tr15-23.html#Decomposition
• [x] Follows the English T9 convention of key assignment

Why I chose dawg for implementation of trie?

Because it's the only implementation that support persisting (serializing), and fast!

TODO

• [x] Decompose accented character.
• [x] Implement number-to-word based on wordlist (saved in database).
• [ ] Implement select candidate key.
• [ ] Support suggestion
• [ ] Flexibility via settings (accents right after character/accent at end of word)
• [ ] Support add new word to dictionary
• [ ] Flick input mode (for registering new word)
• [ ] Frecency algorithm?

References-Acknowledgement

• Vietnamese wordlist : http://www.informatik.uni-leipzig.de/~duc/software/misc/wordlist.html
• Xu ly Tieng Viet wikia: http://xltiengviet.wikia.com/
• https://docs.oracle.com/javase/tutorial/i18n/text/normalizerapi.html
• syllables https://gist.github.com/hieuthi/0f5adb7d3f79e7fb67e0e499004bf558
• spell check dictionary https://saomaicenter.org/en/blog/access-tech/custom-dictionary-for-word
• https://github.com/yweweler/c-t9