This guide should give you everything needed to build a functional T9 keyboard emulator. Start with the basic version, then add features progressively!
acceptWord() ''); this.currentSequence = ''; this.predictions = [];
class SmartT9: def __init__(self): self.word_frequency = {} def get_predictions(self, sequence): words = self.dictionary.get(sequence, []) return sorted(words, key=lambda w: self.word_frequency.get(w, 0), reverse=True)
Store common words mapped to their T9 sequences: t9 keyboard emulator
multi_tap = '2': ['a', 'b', 'c'], '3': ['d', 'e', 'f'], '4': ['g', 'h', 'i'], '5': ['j', 'k', 'l'], '6': ['m', 'n', 'o'], '7': ['p', 'q', 'r', 's'], '8': ['t', 'u', 'v'], '9': ['w', 'x', 'y', 'z']
// Usage const t9 = new T9Emulator(); t9.loadDictionary(['hello', 'good', 'home', 'test', 'world']); console.log(t9.pressKey('4')); // ['good', 'home'] for '4'? Actually '4' = ghi console.log(t9.pressKey('6')); // ['home'] for '46'? Wait, '46' = 'hm'? Let's fix... Here's a starter dictionary with common words:
def get_t9_sequence(word): """Convert a word to its T9 number sequence""" return ''.join(letter_to_key[letter] for letter in word.lower()) def predict(sequence, word_dict): """Return possible words for a T9 sequence""" return word_dict.get(sequence, []) Step 4: Handle Multi-tap Input (Classic T9) For non-predictive mode, implement multi-tap: This guide should give you everything needed to
const starterDictionary = '2': ['a', 'b', 'c'], '22': ['aa', 'ab', 'ac', 'ba', 'bb', 'bc', 'ca', 'cb', 'cc'], '23': ['ad', 'ae', 'af', 'bd', 'be', 'bf', 'cd', 'ce', 'cf'], '4663': ['good', 'home', 'gone', 'hood'], '43556': ['hello'], '96753': ['world', 'words'], '843': ['the', 'tie', 'vid'], '2865': ['bunk', 'cunt', 'auto'], '5464': ['king', 'link', 'jink'], '7364': ['send', 'rend', 'pend'] ; 1. Next Word Prediction Allow cycling through predictions with a "Next" key (usually * ) 2. Add Word to Dictionary Let users add new words that aren't recognized 3. Frequency-Based Sorting Sort predictions by how often the user selects them
nextPrediction() // Cycle through predictions if (this.predictions.length > 1) this.predictions.push(this.predictions.shift()); return this.predictions[0];
def multi_tap_decode(taps): """Decode multi-tap input""" key = taps[0] count = len(taps) letters = multi_tap[key] return letters[(count - 1) % len(letters)] Complete JavaScript Implementation class T9Emulator { constructor() { this.keyMap = '2': 'abc', '3': 'def', '4': 'ghi', '5': 'jkl', '6': 'mno', '7': 'pqrs', '8': 'tuv', '9': 'wxyz', '0': ' ' ; this.dictionary = {}; // Populate with words this.currentSequence = ''; this.predictions = []; } Actually '4' = ghi console
pressKey(key) []; return this.predictions;
}
def input_digit(self, digit): if digit == '0': # Space - finalize current word if self.current_input and self.current_input in self.word_dict: self.output_text += self.word_dict[self.current_input][0] + " " self.current_input = "" else: self.current_input += digit if self.current_input in self.word_dict: return self.word_dict[self.current_input] return []
loadDictionary(words) words.forEach(word => const seq = this.wordToSequence(word); if (!this.dictionary[seq]) this.dictionary[seq] = []; this.dictionary[seq].push(word); );
# Example word dictionary t9_dict = '4663': ['good', 'home', 'gone'], '2273': ['case', 'care', 'base'], '96753': ['words', 'world'], '43556': ['hello'], '843': ['the', 'tie', 'vid']