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A library jar that provides APIs for Applications written for the Google Android Platform.
/*
* 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.annotation.Nullable;
import android.text.Editable;
import android.text.Selection;
import android.text.Spanned;
import android.text.method.WordIterator;
import android.text.style.SpellCheckSpan;
import android.text.style.SuggestionSpan;
import android.util.Log;
import android.util.Range;
import android.view.textservice.SentenceSuggestionsInfo;
import android.view.textservice.SpellCheckerSession;
import android.view.textservice.SpellCheckerSession.SpellCheckerSessionListener;
import android.view.textservice.SpellCheckerSession.SpellCheckerSessionParams;
import android.view.textservice.SuggestionsInfo;
import android.view.textservice.TextInfo;
import android.view.textservice.TextServicesManager;
import com.android.internal.util.ArrayUtils;
import com.android.internal.util.GrowingArrayUtils;
import java.text.BreakIterator;
import java.util.Locale;
/**
* Helper class for TextView. Bridge between the TextView and the Dictionary service.
*
* @hide
*/
public class SpellChecker implements SpellCheckerSessionListener {
private static final String TAG = SpellChecker.class.getSimpleName();
private static final boolean DBG = false;
// 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
// The maximum length of sentence.
private static final int MAX_SENTENCE_LENGTH = WORD_ITERATOR_INTERVAL;
private static final int USE_SPAN_RANGE = -1;
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 chunk 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 SentenceIteratorWrapper mSentenceIterator;
@Nullable
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 = 1;
mIds = ArrayUtils.newUnpaddedIntArray(size);
mSpellCheckSpans = new SpellCheckSpan[mIds.length];
setLocale(mTextView.getSpellCheckerLocale());
mCookie = hashCode();
}
void resetSession() {
closeSession();
mTextServicesManager = mTextView.getTextServicesManagerForUser();
if (mCurrentLocale == null
|| mTextServicesManager == null
|| mTextView.length() == 0
|| !mTextServicesManager.isSpellCheckerEnabled()
|| mTextServicesManager.getCurrentSpellCheckerSubtype(true) == null) {
mSpellCheckerSession = null;
} else {
int supportedAttributes = SuggestionsInfo.RESULT_ATTR_IN_THE_DICTIONARY
| SuggestionsInfo.RESULT_ATTR_LOOKS_LIKE_TYPO
| SuggestionsInfo.RESULT_ATTR_LOOKS_LIKE_GRAMMAR_ERROR
| SuggestionsInfo.RESULT_ATTR_DONT_SHOW_UI_FOR_SUGGESTIONS;
SpellCheckerSessionParams params = new SpellCheckerSessionParams.Builder()
.setLocale(mCurrentLocale)
.setSupportedAttributes(supportedAttributes)
.build();
mSpellCheckerSession = mTextServicesManager.newSpellCheckerSession(
params, mTextView.getContext().getMainExecutor(), this);
}
// Restore SpellCheckSpans in pool
for (int i = 0; i < mLength; i++) {
mIds[i] = -1;
}
mLength = 0;
// Remove existing misspelled SuggestionSpans
mTextView.removeMisspelledSpans((Editable) mTextView.getText());
}
private void setLocale(Locale locale) {
mCurrentLocale = locale;
resetSession();
if (locale != null) {
// Change SpellParsers' sentenceIterator locale
mSentenceIterator = new SentenceIteratorWrapper(
BreakIterator.getSentenceInstance(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;
}
mIds = GrowingArrayUtils.append(mIds, mLength, 0);
mSpellCheckSpans = GrowingArrayUtils.append(
mSpellCheckSpans, mLength, new SpellCheckSpan());
mLength++;
return mLength - 1;
}
private void addSpellCheckSpan(Editable editable, int start, int end) {
final int index = nextSpellCheckSpanIndex();
SpellCheckSpan spellCheckSpan = mSpellCheckSpans[index];
editable.setSpan(spellCheckSpan, start, end, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
spellCheckSpan.setSpellCheckInProgress(false);
mIds[index] = mSpanSequenceCounter++;
}
public void onSpellCheckSpanRemoved(SpellCheckSpan spellCheckSpan) {
// Recycle any removed SpellCheckSpan (from this code or during text edition)
for (int i = 0; i < mLength; i++) {
if (mSpellCheckSpans[i] == spellCheckSpan) {
mIds[i] = -1;
return;
}
}
}
public void onSelectionChanged() {
spellCheck();
}
void onPerformSpellCheck() {
// Triggers full content spell check.
final int start = 0;
final int end = mTextView.length();
if (DBG) {
Log.d(TAG, "performSpellCheckAroundSelection: " + start + ", " + end);
}
spellCheck(start, end, /* forceCheckWhenEditingWord= */ true);
}
public void spellCheck(int start, int end) {
spellCheck(start, end, /* forceCheckWhenEditingWord= */ false);
}
/**
* Requests to do spell check for text in the range (start, end).
*/
public void spellCheck(int start, int end, boolean forceCheckWhenEditingWord) {
if (DBG) {
Log.d(TAG, "Start spell-checking: " + start + ", " + end + ", "
+ forceCheckWhenEditingWord);
}
final Locale locale = mTextView.getSpellCheckerLocale();
final boolean isSessionActive = isSessionActive();
if (locale == null || mCurrentLocale == null || (!(mCurrentLocale.equals(locale)))) {
setLocale(locale);
// Re-check the entire text
start = 0;
end = mTextView.getText().length();
} else {
final boolean spellCheckerActivated =
mTextServicesManager != null && 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.parse(start, end, forceCheckWhenEditingWord);
return;
}
}
if (DBG) {
Log.d(TAG, "new spell parser.");
}
// 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.parse(start, end, forceCheckWhenEditingWord);
}
private void spellCheck() {
spellCheck(/* forceCheckWhenEditingWord= */ false);
}
private void spellCheck(boolean forceCheckWhenEditingWord) {
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;
if (DBG) {
Log.d(TAG, "forceCheckWhenEditingWord=" + forceCheckWhenEditingWord
+ ", mLength=" + mLength + ", cookie = " + mCookie
+ ", sel start = " + selectionStart + ", sel end = " + selectionEnd);
}
for (int i = 0; i < mLength; i++) {
final SpellCheckSpan spellCheckSpan = mSpellCheckSpans[i];
if (mIds[i] < 0 || spellCheckSpan.isSpellCheckInProgress()) continue;
final int start = editable.getSpanStart(spellCheckSpan);
final int end = editable.getSpanEnd(spellCheckSpan);
// Check the span if any of following conditions is met:
// - the user is not currently editing it
// - or `forceCheckWhenEditingWord` is true.
final boolean isNotEditing;
// Defer spell check when typing a word ending with a punctuation like an apostrophe
// which could end up being a mid-word punctuation.
if (selectionStart == end + 1
&& WordIterator.isMidWordPunctuation(
mCurrentLocale, Character.codePointBefore(editable, end + 1))) {
isNotEditing = false;
} else if (selectionEnd <= start || selectionStart > end) {
// Allow the overlap of the cursor and the first boundary of the spell check span
// no to skip the spell check of the following word because the
// following word will never be spell-checked even if the user finishes composing
isNotEditing = true;
} else {
// When cursor is at the end of spell check span, allow spell check if the
// character before cursor is a separator.
isNotEditing = selectionStart == end
&& selectionStart > 0
&& isSeparator(Character.codePointBefore(editable, selectionStart));
}
if (start >= 0 && end > start && (forceCheckWhenEditingWord || isNotEditing)) {
spellCheckSpan.setSpellCheckInProgress(true);
final TextInfo textInfo = new TextInfo(editable, start, end, mCookie, mIds[i]);
textInfos[textInfosCount++] = textInfo;
if (DBG) {
Log.d(TAG, "create TextInfo: (" + i + "/" + mLength + ") text = "
+ textInfo.getSequence() + ", cookie = " + mCookie + ", seq = "
+ mIds[i] + ", sel start = " + selectionStart + ", sel end = "
+ selectionEnd + ", start = " + start + ", end = " + end);
}
}
}
if (textInfosCount > 0) {
if (textInfosCount < textInfos.length) {
TextInfo[] textInfosCopy = new TextInfo[textInfosCount];
System.arraycopy(textInfos, 0, textInfosCopy, 0, textInfosCount);
textInfos = textInfosCopy;
}
mSpellCheckerSession.getSentenceSuggestions(
textInfos, SuggestionSpan.SUGGESTIONS_MAX_SIZE);
}
}
private static boolean isSeparator(int codepoint) {
final int type = Character.getType(codepoint);
return ((1 << type) & ((1 << Character.SPACE_SEPARATOR)
| (1 << Character.LINE_SEPARATOR)
| (1 << Character.PARAGRAPH_SEPARATOR)
| (1 << Character.DASH_PUNCTUATION)
| (1 << Character.END_PUNCTUATION)
| (1 << Character.FINAL_QUOTE_PUNCTUATION)
| (1 << Character.INITIAL_QUOTE_PUNCTUATION)
| (1 << Character.START_PUNCTUATION)
| (1 << Character.OTHER_PUNCTUATION))) != 0;
}
private SpellCheckSpan onGetSuggestionsInternal(
SuggestionsInfo suggestionsInfo, int offset, int length) {
if (suggestionsInfo == null || suggestionsInfo.getCookie() != mCookie) {
return null;
}
final Editable editable = (Editable) mTextView.getText();
final int sequenceNumber = suggestionsInfo.getSequence();
for (int k = 0; k < mLength; ++k) {
if (sequenceNumber == mIds[k]) {
final SpellCheckSpan spellCheckSpan = mSpellCheckSpans[k];
final int spellCheckSpanStart = editable.getSpanStart(spellCheckSpan);
if (spellCheckSpanStart < 0) {
// Skips the suggestion if the matched span has been removed.
return null;
}
final int attributes = suggestionsInfo.getSuggestionsAttributes();
final boolean isInDictionary =
((attributes & SuggestionsInfo.RESULT_ATTR_IN_THE_DICTIONARY) > 0);
final boolean looksLikeTypo =
((attributes & SuggestionsInfo.RESULT_ATTR_LOOKS_LIKE_TYPO) > 0);
final boolean looksLikeGrammarError =
((attributes & SuggestionsInfo.RESULT_ATTR_LOOKS_LIKE_GRAMMAR_ERROR) > 0);
// Validates the suggestions range in case the SpellCheckSpan is out-of-date but not
// removed as expected.
if (spellCheckSpanStart + offset + length > editable.length()) {
return spellCheckSpan;
}
//TODO: we need to change that rule for results from a sentence-level spell
// checker that will probably be in dictionary.
if (!isInDictionary && (looksLikeTypo || looksLikeGrammarError)) {
createMisspelledSuggestionSpan(
editable, suggestionsInfo, spellCheckSpan, offset, length);
} else {
// Valid word -- isInDictionary || !looksLikeTypo
// Allow the spell checker to remove existing misspelled span by
// overwriting the span over the same place
final int spellCheckSpanEnd = editable.getSpanEnd(spellCheckSpan);
final int start;
final int end;
if (offset != USE_SPAN_RANGE && length != USE_SPAN_RANGE) {
start = spellCheckSpanStart + offset;
end = start + length;
} else {
start = spellCheckSpanStart;
end = spellCheckSpanEnd;
}
if (spellCheckSpanStart >= 0 && spellCheckSpanEnd > spellCheckSpanStart
&& end > start) {
removeErrorSuggestionSpan(editable, start, end, RemoveReason.OBSOLETE);
}
}
return spellCheckSpan;
}
}
return null;
}
private enum RemoveReason {
/**
* Indicates the previous SuggestionSpan is replaced by a new SuggestionSpan.
*/
REPLACE,
/**
* Indicates the previous SuggestionSpan is removed because corresponding text is
* considered as valid words now.
*/
OBSOLETE,
}
private static void removeErrorSuggestionSpan(
Editable editable, int start, int end, RemoveReason reason) {
SuggestionSpan[] spans = editable.getSpans(start, end, SuggestionSpan.class);
for (SuggestionSpan span : spans) {
if (editable.getSpanStart(span) == start
&& editable.getSpanEnd(span) == end
&& (span.getFlags() & (SuggestionSpan.FLAG_MISSPELLED
| SuggestionSpan.FLAG_GRAMMAR_ERROR)) != 0) {
if (DBG) {
Log.i(TAG, "Remove existing misspelled/grammar error span on "
+ editable.subSequence(start, end) + ", reason: " + reason);
}
editable.removeSpan(span);
}
}
}
@Override
public void onGetSuggestions(SuggestionsInfo[] results) {
final Editable editable = (Editable) mTextView.getText();
for (int i = 0; i < results.length; ++i) {
final SpellCheckSpan spellCheckSpan =
onGetSuggestionsInternal(results[i], USE_SPAN_RANGE, USE_SPAN_RANGE);
if (spellCheckSpan != null) {
// onSpellCheckSpanRemoved will recycle this span in the pool
editable.removeSpan(spellCheckSpan);
}
}
scheduleNewSpellCheck();
}
@Override
public void onGetSentenceSuggestions(SentenceSuggestionsInfo[] results) {
final Editable editable = (Editable) mTextView.getText();
for (int i = 0; i < results.length; ++i) {
final SentenceSuggestionsInfo ssi = results[i];
if (ssi == null) {
continue;
}
SpellCheckSpan spellCheckSpan = null;
for (int j = 0; j < ssi.getSuggestionsCount(); ++j) {
final SuggestionsInfo suggestionsInfo = ssi.getSuggestionsInfoAt(j);
if (suggestionsInfo == null) {
continue;
}
final int offset = ssi.getOffsetAt(j);
final int length = ssi.getLengthAt(j);
final SpellCheckSpan scs = onGetSuggestionsInternal(
suggestionsInfo, offset, length);
if (spellCheckSpan == null && scs != null) {
// the spellCheckSpan is shared by all the "SuggestionsInfo"s in the same
// SentenceSuggestionsInfo. Removal is deferred after this loop.
spellCheckSpan = scs;
}
}
if (spellCheckSpan != null) {
// onSpellCheckSpanRemoved will recycle this span in the pool
editable.removeSpan(spellCheckSpan);
}
}
scheduleNewSpellCheck();
}
private void scheduleNewSpellCheck() {
if (DBG) {
Log.i(TAG, "schedule new spell check.");
}
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);
}
// When calling this method, RESULT_ATTR_LOOKS_LIKE_TYPO or RESULT_ATTR_LOOKS_LIKE_GRAMMAR_ERROR
// (or both) should be set in suggestionsInfo.
private void createMisspelledSuggestionSpan(Editable editable, SuggestionsInfo suggestionsInfo,
SpellCheckSpan spellCheckSpan, int offset, int length) {
final int spellCheckSpanStart = editable.getSpanStart(spellCheckSpan);
final int spellCheckSpanEnd = editable.getSpanEnd(spellCheckSpan);
if (spellCheckSpanStart < 0 || spellCheckSpanEnd <= spellCheckSpanStart)
return; // span was removed in the meantime
final int start;
final int end;
if (offset != USE_SPAN_RANGE && length != USE_SPAN_RANGE) {
start = spellCheckSpanStart + offset;
end = start + length;
} else {
start = spellCheckSpanStart;
end = spellCheckSpanEnd;
}
final int suggestionsCount = suggestionsInfo.getSuggestionsCount();
String[] suggestions;
if (suggestionsCount > 0) {
suggestions = new String[suggestionsCount];
for (int i = 0; i < suggestionsCount; i++) {
suggestions[i] = suggestionsInfo.getSuggestionAt(i);
}
} else {
suggestions = ArrayUtils.emptyArray(String.class);
}
final int suggestionsAttrs = suggestionsInfo.getSuggestionsAttributes();
int flags = 0;
if ((suggestionsAttrs & SuggestionsInfo.RESULT_ATTR_DONT_SHOW_UI_FOR_SUGGESTIONS) == 0) {
flags |= SuggestionSpan.FLAG_EASY_CORRECT;
}
if ((suggestionsAttrs & SuggestionsInfo.RESULT_ATTR_LOOKS_LIKE_TYPO) != 0) {
flags |= SuggestionSpan.FLAG_MISSPELLED;
}
if ((suggestionsAttrs & SuggestionsInfo.RESULT_ATTR_LOOKS_LIKE_GRAMMAR_ERROR) != 0) {
flags |= SuggestionSpan.FLAG_GRAMMAR_ERROR;
}
SuggestionSpan suggestionSpan =
new SuggestionSpan(mTextView.getContext(), suggestions, flags);
removeErrorSuggestionSpan(editable, start, end, RemoveReason.REPLACE);
editable.setSpan(suggestionSpan, start, end, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
mTextView.invalidateRegion(start, end, false /* No cursor involved */);
}
/**
* A wrapper of sentence iterator which only processes the specified window of the given text.
*/
private static class SentenceIteratorWrapper {
private BreakIterator mSentenceIterator;
private int mStartOffset;
private int mEndOffset;
SentenceIteratorWrapper(BreakIterator sentenceIterator) {
mSentenceIterator = sentenceIterator;
}
/**
* Set the char sequence and the text window to process.
*/
public void setCharSequence(CharSequence sequence, int start, int end) {
mStartOffset = Math.max(0, start);
mEndOffset = Math.min(end, sequence.length());
mSentenceIterator.setText(sequence.subSequence(mStartOffset, mEndOffset).toString());
}
/**
* See {@link BreakIterator#preceding(int)}
*/
public int preceding(int offset) {
if (offset < mStartOffset) {
return BreakIterator.DONE;
}
int result = mSentenceIterator.preceding(offset - mStartOffset);
return result == BreakIterator.DONE ? BreakIterator.DONE : result + mStartOffset;
}
/**
* See {@link BreakIterator#following(int)}
*/
public int following(int offset) {
if (offset > mEndOffset) {
return BreakIterator.DONE;
}
int result = mSentenceIterator.following(offset - mStartOffset);
return result == BreakIterator.DONE ? BreakIterator.DONE : result + mStartOffset;
}
/**
* See {@link BreakIterator#isBoundary(int)}
*/
public boolean isBoundary(int offset) {
if (offset < mStartOffset || offset > mEndOffset) {
return false;
}
return mSentenceIterator.isBoundary(offset - mStartOffset);
}
}
private class SpellParser {
private Object mRange = new Object();
// Forces to do spell checker even user is editing the word.
private boolean mForceCheckWhenEditingWord;
public void parse(int start, int end, boolean forceCheckWhenEditingWord) {
mForceCheckWhenEditingWord = forceCheckWhenEditingWord;
final int max = mTextView.length();
final int parseEnd;
if (end > max) {
Log.w(TAG, "Parse invalid region, from " + start + " to " + end);
parseEnd = max;
} else {
parseEnd = end;
}
if (parseEnd > start) {
setRangeSpan((Editable) mTextView.getText(), start, parseEnd);
parse();
}
}
public boolean isFinished() {
return ((Editable) mTextView.getText()).getSpanStart(mRange) < 0;
}
public void stop() {
removeRangeSpan((Editable) mTextView.getText());
mForceCheckWhenEditingWord = false;
}
private void setRangeSpan(Editable editable, int start, int end) {
if (DBG) {
Log.d(TAG, "set next range span: " + start + ", " + end);
}
editable.setSpan(mRange, start, end, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
}
private void removeRangeSpan(Editable editable) {
if (DBG) {
Log.d(TAG, "Remove range span." + editable.getSpanStart(editable)
+ editable.getSpanEnd(editable));
}
editable.removeSpan(mRange);
}
public void parse() {
Editable editable = (Editable) mTextView.getText();
final int textChangeStart = editable.getSpanStart(mRange);
final int textChangeEnd = editable.getSpanEnd(mRange);
Range sentenceBoundary = detectSentenceBoundary(editable, textChangeStart,
textChangeEnd);
int sentenceStart = sentenceBoundary.getLower();
int sentenceEnd = sentenceBoundary.getUpper();
if (sentenceStart == sentenceEnd) {
if (DBG) {
Log.i(TAG, "No more spell check.");
}
stop();
return;
}
boolean scheduleOtherSpellCheck = false;
if (sentenceEnd < textChangeEnd) {
if (DBG) {
Log.i(TAG, "schedule other spell check.");
}
// Several batches needed on that region. Cut after last previous word
scheduleOtherSpellCheck = true;
}
int spellCheckEnd = sentenceEnd;
do {
int spellCheckStart = sentenceStart;
boolean createSpellCheckSpan = true;
// Cancel or merge overlapped spell check spans
for (int i = 0; i < mLength; ++i) {
final SpellCheckSpan spellCheckSpan = mSpellCheckSpans[i];
if (mIds[i] < 0 || spellCheckSpan.isSpellCheckInProgress()) {
continue;
}
final int spanStart = editable.getSpanStart(spellCheckSpan);
final int spanEnd = editable.getSpanEnd(spellCheckSpan);
if (spanEnd < spellCheckStart || spellCheckEnd < spanStart) {
// No need to merge
continue;
}
if (spanStart <= spellCheckStart && spellCheckEnd <= spanEnd) {
// There is a completely overlapped spell check span
// skip this span
createSpellCheckSpan = false;
if (DBG) {
Log.i(TAG, "The range is overrapped. Skip spell check.");
}
break;
}
// This spellCheckSpan is replaced by the one we are creating
editable.removeSpan(spellCheckSpan);
spellCheckStart = Math.min(spanStart, spellCheckStart);
spellCheckEnd = Math.max(spanEnd, spellCheckEnd);
}
if (DBG) {
Log.d(TAG, "addSpellCheckSpan: "
+ ", End = " + spellCheckEnd + ", Start = " + spellCheckStart
+ ", next = " + scheduleOtherSpellCheck + "\n"
+ editable.subSequence(spellCheckStart, spellCheckEnd));
}
// Stop spell checking when there are no characters in the range.
if (spellCheckEnd <= spellCheckStart) {
Log.w(TAG, "Trying to spellcheck invalid region, from "
+ sentenceStart + " to " + spellCheckEnd);
break;
}
if (createSpellCheckSpan) {
addSpellCheckSpan(editable, spellCheckStart, spellCheckEnd);
}
} while (false);
sentenceStart = spellCheckEnd;
if (scheduleOtherSpellCheck && sentenceStart != BreakIterator.DONE
&& sentenceStart <= textChangeEnd) {
// Update range span: start new spell check from last wordStart
setRangeSpan(editable, sentenceStart, textChangeEnd);
} else {
removeRangeSpan(editable);
}
spellCheck(mForceCheckWhenEditingWord);
}
private 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);
}
}
}
private Range detectSentenceBoundary(CharSequence sequence,
int textChangeStart, int textChangeEnd) {
// Only process a substring of the full text due to performance concern.
final int iteratorWindowStart = findSeparator(sequence,
Math.max(0, textChangeStart - MAX_SENTENCE_LENGTH),
Math.max(0, textChangeStart - 2 * MAX_SENTENCE_LENGTH));
final int iteratorWindowEnd = findSeparator(sequence,
Math.min(textChangeStart + 2 * MAX_SENTENCE_LENGTH, textChangeEnd),
Math.min(textChangeStart + 3 * MAX_SENTENCE_LENGTH, sequence.length()));
if (DBG) {
Log.d(TAG, "Set iterator window as [" + iteratorWindowStart + ", " + iteratorWindowEnd
+ ").");
}
mSentenceIterator.setCharSequence(sequence, iteratorWindowStart, iteratorWindowEnd);
// Detect the offset of sentence begin/end on the substring.
int sentenceStart = mSentenceIterator.isBoundary(textChangeStart) ? textChangeStart
: mSentenceIterator.preceding(textChangeStart);
int sentenceEnd = mSentenceIterator.following(sentenceStart);
if (sentenceEnd == BreakIterator.DONE) {
sentenceEnd = iteratorWindowEnd;
}
if (DBG) {
if (sentenceStart != sentenceEnd) {
Log.d(TAG, "Sentence detected [" + sentenceStart + ", " + sentenceEnd + ").");
}
}
if (sentenceEnd - sentenceStart <= MAX_SENTENCE_LENGTH) {
// Add more sentences until the MAX_SENTENCE_LENGTH limitation is reached.
while (sentenceEnd < textChangeEnd) {
int nextEnd = mSentenceIterator.following(sentenceEnd);
if (nextEnd == BreakIterator.DONE
|| nextEnd - sentenceStart > MAX_SENTENCE_LENGTH) {
break;
}
sentenceEnd = nextEnd;
}
} else {
// If the sentence containing `textChangeStart` is longer than MAX_SENTENCE_LENGTH,
// the sentence will be sliced into sub-sentences of about MAX_SENTENCE_LENGTH
// characters each. This is done by processing the unchecked part of that sentence :
// [textChangeStart, sentenceEnd)
//
// - If the `uncheckedLength` is bigger than MAX_SENTENCE_LENGTH, then check the
// [textChangeStart, textChangeStart + MAX_SENTENCE_LENGTH), and leave the rest
// part for the next check.
//
// - If the `uncheckedLength` is smaller than or equal to MAX_SENTENCE_LENGTH,
// then check [sentenceEnd - MAX_SENTENCE_LENGTH, sentenceEnd).
//
// The offset should be rounded up to word boundary.
int uncheckedLength = sentenceEnd - textChangeStart;
if (uncheckedLength > MAX_SENTENCE_LENGTH) {
sentenceEnd = findSeparator(sequence, textChangeStart + MAX_SENTENCE_LENGTH,
sentenceEnd);
sentenceStart = roundUpToWordStart(sequence, textChangeStart, sentenceStart);
} else {
sentenceStart = roundUpToWordStart(sequence, sentenceEnd - MAX_SENTENCE_LENGTH,
sentenceStart);
}
}
return new Range<>(sentenceStart, Math.max(sentenceStart, sentenceEnd));
}
private int roundUpToWordStart(CharSequence sequence, int position, int frontBoundary) {
if (isSeparator(sequence.charAt(position))) {
return position;
}
int separator = findSeparator(sequence, position, frontBoundary);
return separator != frontBoundary ? separator + 1 : frontBoundary;
}
/**
* Search the range [start, end) of sequence and returns the position of the first separator.
* If end is smaller than start, do a reverse search.
* Returns `end` if no separator is found.
*/
private static int findSeparator(CharSequence sequence, int start, int end) {
final int step = start < end ? 1 : -1;
for (int i = start; i != end; i += step) {
if (isSeparator(sequence.charAt(i))) {
return i;
}
}
return end;
}
public static boolean haveWordBoundariesChanged(final Editable editable, final int start,
final int end, final int spanStart, final int spanEnd) {
final boolean haveWordBoundariesChanged;
if (spanEnd != start && spanStart != end) {
haveWordBoundariesChanged = true;
if (DBG) {
Log.d(TAG, "(1) Text inside the span has been modified. Remove.");
}
} else if (spanEnd == start && start < editable.length()) {
final int codePoint = Character.codePointAt(editable, start);
haveWordBoundariesChanged = Character.isLetterOrDigit(codePoint);
if (DBG) {
Log.d(TAG, "(2) Characters have been appended to the spanned text. "
+ (haveWordBoundariesChanged ? "Remove.<" : "Keep. <") + (char)(codePoint)
+ ">, " + editable + ", " + editable.subSequence(spanStart, spanEnd) + ", "
+ start);
}
} else if (spanStart == end && end > 0) {
final int codePoint = Character.codePointBefore(editable, end);
haveWordBoundariesChanged = Character.isLetterOrDigit(codePoint);
if (DBG) {
Log.d(TAG, "(3) Characters have been prepended to the spanned text. "
+ (haveWordBoundariesChanged ? "Remove.<" : "Keep.<") + (char)(codePoint)
+ ">, " + editable + ", " + editable.subSequence(spanStart, spanEnd) + ", "
+ end);
}
} else {
if (DBG) {
Log.d(TAG, "(4) Characters adjacent to the spanned text were deleted. Keep.");
}
haveWordBoundariesChanged = false;
}
return haveWordBoundariesChanged;
}
}