| /* |
| * Copyright (C) 2011 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package android.widget; |
| |
| import android.content.Context; |
| import android.text.Editable; |
| import android.text.Selection; |
| import android.text.SpannableStringBuilder; |
| import android.text.Spanned; |
| import android.text.method.WordIterator; |
| import android.text.style.SpellCheckSpan; |
| import android.text.style.SuggestionSpan; |
| import android.view.textservice.SpellCheckerSession; |
| import android.view.textservice.SpellCheckerSession.SpellCheckerSessionListener; |
| import android.view.textservice.SuggestionsInfo; |
| import android.view.textservice.TextInfo; |
| import android.view.textservice.TextServicesManager; |
| |
| import com.android.internal.util.ArrayUtils; |
| |
| import java.text.BreakIterator; |
| import java.util.Locale; |
| |
| |
| /** |
| * Helper class for TextView. Bridge between the TextView and the Dictionnary service. |
| * |
| * @hide |
| */ |
| public class SpellChecker implements SpellCheckerSessionListener { |
| |
| // No more than this number of words will be parsed on each iteration to ensure a minimum |
| // lock of the UI thread |
| public static final int MAX_NUMBER_OF_WORDS = 50; |
| |
| // Rough estimate, such that the word iterator interval usually does not need to be shifted |
| public static final int AVERAGE_WORD_LENGTH = 7; |
| |
| // When parsing, use a character window of that size. Will be shifted if needed |
| public static final int WORD_ITERATOR_INTERVAL = AVERAGE_WORD_LENGTH * MAX_NUMBER_OF_WORDS; |
| |
| // Pause between each spell check to keep the UI smooth |
| private final static int SPELL_PAUSE_DURATION = 400; // milliseconds |
| |
| private final TextView mTextView; |
| |
| SpellCheckerSession mSpellCheckerSession; |
| final int mCookie; |
| |
| // Paired arrays for the (id, spellCheckSpan) pair. A negative id means the associated |
| // SpellCheckSpan has been recycled and can be-reused. |
| // Contains null SpellCheckSpans after index mLength. |
| private int[] mIds; |
| private SpellCheckSpan[] mSpellCheckSpans; |
| // The mLength first elements of the above arrays have been initialized |
| private int mLength; |
| |
| // Parsers on chunck of text, cutting text into words that will be checked |
| private SpellParser[] mSpellParsers = new SpellParser[0]; |
| |
| private int mSpanSequenceCounter = 0; |
| |
| private Locale mCurrentLocale; |
| |
| // Shared by all SpellParsers. Cannot be shared with TextView since it may be used |
| // concurrently due to the asynchronous nature of onGetSuggestions. |
| private WordIterator mWordIterator; |
| |
| private TextServicesManager mTextServicesManager; |
| |
| private Runnable mSpellRunnable; |
| |
| public SpellChecker(TextView textView) { |
| mTextView = textView; |
| |
| // Arbitrary: these arrays will automatically double their sizes on demand |
| final int size = ArrayUtils.idealObjectArraySize(1); |
| mIds = new int[size]; |
| mSpellCheckSpans = new SpellCheckSpan[size]; |
| |
| setLocale(mTextView.getTextServicesLocale()); |
| |
| mCookie = hashCode(); |
| } |
| |
| private void resetSession() { |
| closeSession(); |
| |
| mTextServicesManager = (TextServicesManager) mTextView.getContext(). |
| getSystemService(Context.TEXT_SERVICES_MANAGER_SERVICE); |
| if (!mTextServicesManager.isSpellCheckerEnabled() |
| || mTextServicesManager.getCurrentSpellCheckerSubtype(true) == null) { |
| mSpellCheckerSession = null; |
| } else { |
| mSpellCheckerSession = mTextServicesManager.newSpellCheckerSession( |
| null /* Bundle not currently used by the textServicesManager */, |
| mCurrentLocale, this, |
| false /* means any available languages from current spell checker */); |
| } |
| |
| // Restore SpellCheckSpans in pool |
| for (int i = 0; i < mLength; i++) { |
| mSpellCheckSpans[i].setSpellCheckInProgress(false); |
| mIds[i] = -1; |
| } |
| mLength = 0; |
| |
| // Remove existing misspelled SuggestionSpans |
| mTextView.removeMisspelledSpans((Editable) mTextView.getText()); |
| } |
| |
| private void setLocale(Locale locale) { |
| mCurrentLocale = locale; |
| |
| resetSession(); |
| |
| // Change SpellParsers' wordIterator locale |
| mWordIterator = new WordIterator(locale); |
| |
| // This class is the listener for locale change: warn other locale-aware objects |
| mTextView.onLocaleChanged(); |
| } |
| |
| /** |
| * @return true if a spell checker session has successfully been created. Returns false if not, |
| * for instance when spell checking has been disabled in settings. |
| */ |
| private boolean isSessionActive() { |
| return mSpellCheckerSession != null; |
| } |
| |
| public void closeSession() { |
| if (mSpellCheckerSession != null) { |
| mSpellCheckerSession.close(); |
| } |
| |
| final int length = mSpellParsers.length; |
| for (int i = 0; i < length; i++) { |
| mSpellParsers[i].stop(); |
| } |
| |
| if (mSpellRunnable != null) { |
| mTextView.removeCallbacks(mSpellRunnable); |
| } |
| } |
| |
| private int nextSpellCheckSpanIndex() { |
| for (int i = 0; i < mLength; i++) { |
| if (mIds[i] < 0) return i; |
| } |
| |
| if (mLength == mSpellCheckSpans.length) { |
| final int newSize = mLength * 2; |
| int[] newIds = new int[newSize]; |
| SpellCheckSpan[] newSpellCheckSpans = new SpellCheckSpan[newSize]; |
| System.arraycopy(mIds, 0, newIds, 0, mLength); |
| System.arraycopy(mSpellCheckSpans, 0, newSpellCheckSpans, 0, mLength); |
| mIds = newIds; |
| mSpellCheckSpans = newSpellCheckSpans; |
| } |
| |
| mSpellCheckSpans[mLength] = new SpellCheckSpan(); |
| mLength++; |
| return mLength - 1; |
| } |
| |
| private void addSpellCheckSpan(Editable editable, int start, int end) { |
| final int index = nextSpellCheckSpanIndex(); |
| editable.setSpan(mSpellCheckSpans[index], start, end, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE); |
| mIds[index] = mSpanSequenceCounter++; |
| } |
| |
| public void removeSpellCheckSpan(SpellCheckSpan spellCheckSpan) { |
| for (int i = 0; i < mLength; i++) { |
| if (mSpellCheckSpans[i] == spellCheckSpan) { |
| mSpellCheckSpans[i].setSpellCheckInProgress(false); |
| mIds[i] = -1; |
| return; |
| } |
| } |
| } |
| |
| public void onSelectionChanged() { |
| spellCheck(); |
| } |
| |
| public void spellCheck(int start, int end) { |
| final Locale locale = mTextView.getTextServicesLocale(); |
| if (mCurrentLocale == null || (!(mCurrentLocale.equals(locale)))) { |
| setLocale(locale); |
| // Re-check the entire text |
| start = 0; |
| end = mTextView.getText().length(); |
| } else { |
| final boolean spellCheckerActivated = mTextServicesManager.isSpellCheckerEnabled(); |
| if (isSessionActive() != spellCheckerActivated) { |
| // Spell checker has been turned of or off since last spellCheck |
| resetSession(); |
| } |
| } |
| |
| if (!isSessionActive()) return; |
| |
| // Find first available SpellParser from pool |
| final int length = mSpellParsers.length; |
| for (int i = 0; i < length; i++) { |
| final SpellParser spellParser = mSpellParsers[i]; |
| if (spellParser.isFinished()) { |
| spellParser.init(start, end); |
| spellParser.parse(); |
| return; |
| } |
| } |
| |
| // No available parser found in pool, create a new one |
| SpellParser[] newSpellParsers = new SpellParser[length + 1]; |
| System.arraycopy(mSpellParsers, 0, newSpellParsers, 0, length); |
| mSpellParsers = newSpellParsers; |
| |
| SpellParser spellParser = new SpellParser(); |
| mSpellParsers[length] = spellParser; |
| spellParser.init(start, end); |
| spellParser.parse(); |
| } |
| |
| private void spellCheck() { |
| if (mSpellCheckerSession == null) return; |
| |
| Editable editable = (Editable) mTextView.getText(); |
| final int selectionStart = Selection.getSelectionStart(editable); |
| final int selectionEnd = Selection.getSelectionEnd(editable); |
| |
| TextInfo[] textInfos = new TextInfo[mLength]; |
| int textInfosCount = 0; |
| |
| for (int i = 0; i < mLength; i++) { |
| final SpellCheckSpan spellCheckSpan = mSpellCheckSpans[i]; |
| if (spellCheckSpan.isSpellCheckInProgress()) continue; |
| |
| final int start = editable.getSpanStart(spellCheckSpan); |
| final int end = editable.getSpanEnd(spellCheckSpan); |
| |
| // Do not check this word if the user is currently editing it |
| if (start >= 0 && end > start && (selectionEnd < start || selectionStart > end)) { |
| final String word = (editable instanceof SpannableStringBuilder) ? |
| ((SpannableStringBuilder) editable).substring(start, end) : |
| editable.subSequence(start, end).toString(); |
| spellCheckSpan.setSpellCheckInProgress(true); |
| textInfos[textInfosCount++] = new TextInfo(word, mCookie, mIds[i]); |
| } |
| } |
| |
| if (textInfosCount > 0) { |
| if (textInfosCount < textInfos.length) { |
| TextInfo[] textInfosCopy = new TextInfo[textInfosCount]; |
| System.arraycopy(textInfos, 0, textInfosCopy, 0, textInfosCount); |
| textInfos = textInfosCopy; |
| } |
| |
| mSpellCheckerSession.getSuggestions(textInfos, SuggestionSpan.SUGGESTIONS_MAX_SIZE, |
| false /* TODO Set sequentialWords to true for initial spell check */); |
| } |
| } |
| |
| @Override |
| public void onGetSuggestionsForSentence(SuggestionsInfo[] results) { |
| // TODO: Handle the position and length for each suggestion |
| onGetSuggestions(results); |
| } |
| |
| @Override |
| public void onGetSuggestions(SuggestionsInfo[] results) { |
| Editable editable = (Editable) mTextView.getText(); |
| |
| for (int i = 0; i < results.length; i++) { |
| SuggestionsInfo suggestionsInfo = results[i]; |
| if (suggestionsInfo.getCookie() != mCookie) continue; |
| final int sequenceNumber = suggestionsInfo.getSequence(); |
| |
| for (int j = 0; j < mLength; j++) { |
| if (sequenceNumber == mIds[j]) { |
| final int attributes = suggestionsInfo.getSuggestionsAttributes(); |
| boolean isInDictionary = |
| ((attributes & SuggestionsInfo.RESULT_ATTR_IN_THE_DICTIONARY) > 0); |
| boolean looksLikeTypo = |
| ((attributes & SuggestionsInfo.RESULT_ATTR_LOOKS_LIKE_TYPO) > 0); |
| |
| SpellCheckSpan spellCheckSpan = mSpellCheckSpans[j]; |
| |
| if (!isInDictionary && looksLikeTypo) { |
| createMisspelledSuggestionSpan(editable, suggestionsInfo, spellCheckSpan); |
| } |
| |
| editable.removeSpan(spellCheckSpan); |
| break; |
| } |
| } |
| } |
| |
| scheduleNewSpellCheck(); |
| } |
| |
| private void scheduleNewSpellCheck() { |
| if (mSpellRunnable == null) { |
| mSpellRunnable = new Runnable() { |
| @Override |
| public void run() { |
| final int length = mSpellParsers.length; |
| for (int i = 0; i < length; i++) { |
| final SpellParser spellParser = mSpellParsers[i]; |
| if (!spellParser.isFinished()) { |
| spellParser.parse(); |
| break; // run one spell parser at a time to bound running time |
| } |
| } |
| } |
| }; |
| } else { |
| mTextView.removeCallbacks(mSpellRunnable); |
| } |
| |
| mTextView.postDelayed(mSpellRunnable, SPELL_PAUSE_DURATION); |
| } |
| |
| private void createMisspelledSuggestionSpan(Editable editable, SuggestionsInfo suggestionsInfo, |
| SpellCheckSpan spellCheckSpan) { |
| final int start = editable.getSpanStart(spellCheckSpan); |
| final int end = editable.getSpanEnd(spellCheckSpan); |
| if (start < 0 || end <= start) return; // span was removed in the meantime |
| |
| final int suggestionsCount = suggestionsInfo.getSuggestionsCount(); |
| if (suggestionsCount <= 0) { |
| // A negative suggestion count is possible |
| return; |
| } |
| |
| String[] suggestions = new String[suggestionsCount]; |
| for (int i = 0; i < suggestionsCount; i++) { |
| suggestions[i] = suggestionsInfo.getSuggestionAt(i); |
| } |
| |
| SuggestionSpan suggestionSpan = new SuggestionSpan(mTextView.getContext(), suggestions, |
| SuggestionSpan.FLAG_EASY_CORRECT | SuggestionSpan.FLAG_MISSPELLED); |
| editable.setSpan(suggestionSpan, start, end, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE); |
| |
| mTextView.invalidateRegion(start, end, false /* No cursor involved */); |
| } |
| |
| private class SpellParser { |
| private Object mRange = new Object(); |
| |
| public void init(int start, int end) { |
| setRangeSpan((Editable) mTextView.getText(), start, end); |
| } |
| |
| public boolean isFinished() { |
| return ((Editable) mTextView.getText()).getSpanStart(mRange) < 0; |
| } |
| |
| public void stop() { |
| removeRangeSpan((Editable) mTextView.getText()); |
| } |
| |
| private void setRangeSpan(Editable editable, int start, int end) { |
| editable.setSpan(mRange, start, end, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE); |
| } |
| |
| private void removeRangeSpan(Editable editable) { |
| editable.removeSpan(mRange); |
| } |
| |
| public void parse() { |
| Editable editable = (Editable) mTextView.getText(); |
| // Iterate over the newly added text and schedule new SpellCheckSpans |
| final int start = editable.getSpanStart(mRange); |
| final int end = editable.getSpanEnd(mRange); |
| |
| int wordIteratorWindowEnd = Math.min(end, start + WORD_ITERATOR_INTERVAL); |
| mWordIterator.setCharSequence(editable, start, wordIteratorWindowEnd); |
| |
| // Move back to the beginning of the current word, if any |
| int wordStart = mWordIterator.preceding(start); |
| int wordEnd; |
| if (wordStart == BreakIterator.DONE) { |
| wordEnd = mWordIterator.following(start); |
| if (wordEnd != BreakIterator.DONE) { |
| wordStart = mWordIterator.getBeginning(wordEnd); |
| } |
| } else { |
| wordEnd = mWordIterator.getEnd(wordStart); |
| } |
| if (wordEnd == BreakIterator.DONE) { |
| removeRangeSpan(editable); |
| return; |
| } |
| |
| // We need to expand by one character because we want to include the spans that |
| // end/start at position start/end respectively. |
| SpellCheckSpan[] spellCheckSpans = editable.getSpans(start - 1, end + 1, |
| SpellCheckSpan.class); |
| SuggestionSpan[] suggestionSpans = editable.getSpans(start - 1, end + 1, |
| SuggestionSpan.class); |
| |
| int wordCount = 0; |
| boolean scheduleOtherSpellCheck = false; |
| |
| while (wordStart <= end) { |
| if (wordEnd >= start && wordEnd > wordStart) { |
| if (wordCount >= MAX_NUMBER_OF_WORDS) { |
| scheduleOtherSpellCheck = true; |
| break; |
| } |
| |
| // A new word has been created across the interval boundaries with this edit. |
| // Previous spans (ended on start / started on end) removed, not valid anymore |
| if (wordStart < start && wordEnd > start) { |
| removeSpansAt(editable, start, spellCheckSpans); |
| removeSpansAt(editable, start, suggestionSpans); |
| } |
| |
| if (wordStart < end && wordEnd > end) { |
| removeSpansAt(editable, end, spellCheckSpans); |
| removeSpansAt(editable, end, suggestionSpans); |
| } |
| |
| // Do not create new boundary spans if they already exist |
| boolean createSpellCheckSpan = true; |
| if (wordEnd == start) { |
| for (int i = 0; i < spellCheckSpans.length; i++) { |
| final int spanEnd = editable.getSpanEnd(spellCheckSpans[i]); |
| if (spanEnd == start) { |
| createSpellCheckSpan = false; |
| break; |
| } |
| } |
| } |
| |
| if (wordStart == end) { |
| for (int i = 0; i < spellCheckSpans.length; i++) { |
| final int spanStart = editable.getSpanStart(spellCheckSpans[i]); |
| if (spanStart == end) { |
| createSpellCheckSpan = false; |
| break; |
| } |
| } |
| } |
| |
| if (createSpellCheckSpan) { |
| addSpellCheckSpan(editable, wordStart, wordEnd); |
| } |
| wordCount++; |
| } |
| |
| // iterate word by word |
| int originalWordEnd = wordEnd; |
| wordEnd = mWordIterator.following(wordEnd); |
| if ((wordIteratorWindowEnd < end) && |
| (wordEnd == BreakIterator.DONE || wordEnd >= wordIteratorWindowEnd)) { |
| wordIteratorWindowEnd = Math.min(end, originalWordEnd + WORD_ITERATOR_INTERVAL); |
| mWordIterator.setCharSequence(editable, originalWordEnd, wordIteratorWindowEnd); |
| wordEnd = mWordIterator.following(originalWordEnd); |
| } |
| if (wordEnd == BreakIterator.DONE) break; |
| wordStart = mWordIterator.getBeginning(wordEnd); |
| if (wordStart == BreakIterator.DONE) { |
| break; |
| } |
| } |
| |
| if (scheduleOtherSpellCheck) { |
| // Update range span: start new spell check from last wordStart |
| setRangeSpan(editable, wordStart, end); |
| } else { |
| removeRangeSpan(editable); |
| } |
| |
| spellCheck(); |
| } |
| |
| private <T> void removeSpansAt(Editable editable, int offset, T[] spans) { |
| final int length = spans.length; |
| for (int i = 0; i < length; i++) { |
| final T span = spans[i]; |
| final int start = editable.getSpanStart(span); |
| if (start > offset) continue; |
| final int end = editable.getSpanEnd(span); |
| if (end < offset) continue; |
| editable.removeSpan(span); |
| } |
| } |
| } |
| } |