Correction improvements - use the new InputConnection APIs for underlining and

fetching the selected text.

Bug: 2950652

Some refinements to correction behavior, such as retaining the tap-to-save
when in correction mode.

Use reflection to access the new InputConnection APIs with fallbacks, in case
we run on older OS versions.

Some refactoring to separate lookup for voice alternatives and typed alternatives.

Change-Id: I7c4178bf7e6b47ee274c49fa7a694f8c2d50cea7

1 files changed, 133 insertions, 134 deletions

diff --git a/java/src/com/android/inputmethod/latin/LatinIME.java b/java/src/com/android/inputmethod/latin/LatinIME.java
index 9312ce2c8..76f774c96 100644
--- a/java/src/com/android/inputmethod/latin/LatinIME.java
+++ b/java/src/com/android/inputmethod/latin/LatinIME.java
@@ -86,7 +86,6 @@ public class LatinIME extends InputMethodService
     static final boolean TRACE = false;
     static final boolean VOICE_INSTALLED = true;
     static final boolean ENABLE_VOICE_BUTTON = true;
-    private static final boolean MODIFY_TEXT_FOR_CORRECTION = false;
 
     private static final String PREF_VIBRATE_ON = "vibrate_on";
     private static final String PREF_SOUND_ON = "sound_on";
@@ -767,16 +766,21 @@ public class LatinIME extends InputMethodService
         mLastSelectionEnd = newSelEnd;
 
 
-        // Check if we should go in or out of correction mode.
-        if (isPredictionOn() && mJustRevertedSeparator == null
-                && (candidatesStart == candidatesEnd || newSelStart != oldSelStart
-                        || TextEntryState.isCorrecting())
-                && (newSelStart < newSelEnd - 1 || (!mPredicting))
-                && !mVoiceInputHighlighted) {
-            if (isCursorTouchingWord() || mLastSelectionStart < mLastSelectionEnd) {
-                postUpdateOldSuggestions();
-            } else {
-                abortCorrection(false);
+        // Don't look for corrections if the keyboard is not visible
+        if (mKeyboardSwitcher != null && mKeyboardSwitcher.getInputView() != null
+                && mKeyboardSwitcher.getInputView().isShown()) {
+            // Check if we should go in or out of correction mode.
+            if (isPredictionOn()
+                    && mJustRevertedSeparator == null
+                    && (candidatesStart == candidatesEnd || newSelStart != oldSelStart
+                            || TextEntryState.isCorrecting())
+                    && (newSelStart < newSelEnd - 1 || (!mPredicting))
+                    && !mVoiceInputHighlighted) {
+                if (isCursorTouchingWord() || mLastSelectionStart < mLastSelectionEnd) {
+                    postUpdateOldSuggestions();
+                } else {
+                    abortCorrection(false);
+                }
             }
         }
     }
@@ -818,7 +822,7 @@ public class LatinIME extends InputMethodService
         if (mCompletionOn) {
             mCompletions = completions;
             if (completions == null) {
-                setSuggestions(null, false, false, false);
+                clearSuggestions();
                 return;
             }
 
@@ -1253,7 +1257,7 @@ public class LatinIME extends InputMethodService
     private void abortCorrection(boolean force) {
         if (force || TextEntryState.isCorrecting()) {
             getCurrentInputConnection().finishComposingText();
-            setSuggestions(null, false, false, false);
+            clearSuggestions();
         }
     }
 
@@ -1266,7 +1270,9 @@ public class LatinIME extends InputMethodService
             // Assume input length is 1. This assumption fails for smiley face insertions.
             mVoiceInput.incrementTextModificationInsertCount(1);
         }
-        abortCorrection(false);
+        if (mLastSelectionStart == mLastSelectionEnd && TextEntryState.isCorrecting()) {
+            abortCorrection(false);
+        }
 
         if (isAlphabet(primaryCode) && isPredictionOn() && !isCursorTouchingWord()) {
             if (!mPredicting) {
@@ -1495,7 +1501,7 @@ public class LatinIME extends InputMethodService
         }
 
         // Clear N-best suggestions
-        setSuggestions(null, false, false, true);
+        clearSuggestions();
 
         FieldContext context = new FieldContext(
             getCurrentInputConnection(),
@@ -1602,13 +1608,15 @@ public class LatinIME extends InputMethodService
 
         mVoiceInputHighlighted = true;
         mWordToSuggestions.putAll(mVoiceResults.alternatives);
+    }
 
+    private void clearSuggestions() {
+        setSuggestions(null, false, false, false);
     }
 
     private void setSuggestions(
             List<CharSequence> suggestions,
             boolean completions,
-
             boolean typedWordValid,
             boolean haveMinimalSuggestion) {
 
@@ -1652,14 +1660,14 @@ public class LatinIME extends InputMethodService
     }
 
     private void showSuggestions(WordComposer word) {
-        //long startTime = System.currentTimeMillis(); // TIME MEASUREMENT!
+        // long startTime = System.currentTimeMillis(); // TIME MEASUREMENT!
         // TODO Maybe need better way of retrieving previous word
         CharSequence prevWord = EditingUtil.getPreviousWord(getCurrentInputConnection(),
                 mWordSeparators);
         List<CharSequence> stringList = mSuggest.getSuggestions(
-            mKeyboardSwitcher.getInputView(), word, false, prevWord);
-        //long stopTime = System.currentTimeMillis(); // TIME MEASUREMENT!
-        //Log.d("LatinIME","Suggest Total Time - " + (stopTime - startTime));
+                mKeyboardSwitcher.getInputView(), word, false, prevWord);
+        // long stopTime = System.currentTimeMillis(); // TIME MEASUREMENT!
+        // Log.d("LatinIME","Suggest Total Time - " + (stopTime - startTime));
 
         int[] nextLettersFrequencies = mSuggest.getNextLettersFrequencies();
 
@@ -1780,18 +1788,23 @@ public class LatinIME extends InputMethodService
             mJustAddedAutoSpace = true;
         }
 
-        // Fool the state watcher so that a subsequent backspace will not do a revert, unless
-        // we just did a correction, in which case we need to stay in
-        // TextEntryState.State.PICKED_SUGGESTION state.
+        final boolean showingAddToDictionaryHint = index == 0 && mCorrectionMode > 0
+                && !mSuggest.isValidWord(suggestion)
+                && !mSuggest.isValidWord(suggestion.toString().toLowerCase());
+
         if (!correcting) {
+            // Fool the state watcher so that a subsequent backspace will not do a revert, unless
+            // we just did a correction, in which case we need to stay in
+            // TextEntryState.State.PICKED_SUGGESTION state.
             TextEntryState.typedCharacter((char) KEYCODE_SPACE, true);
             setNextSuggestions();
-        } else {
+        } else if (!showingAddToDictionaryHint) {
+            // If we're not showing the "Tap again to save hint", then show corrections again.
             // In case the cursor position doesn't change, make sure we show the suggestions again.
+            clearSuggestions();
             postUpdateOldSuggestions();
         }
-        if (index == 0 && mCorrectionMode > 0 && !mSuggest.isValidWord(suggestion)
-                && !mSuggest.isValidWord(suggestion.toString().toLowerCase())) {
+        if (showingAddToDictionaryHint) {
             mCandidateView.showAddToDictionaryHint(suggestion);
         }
         if (ic != null) {
@@ -1841,16 +1854,6 @@ public class LatinIME extends InputMethodService
         InputConnection ic = getCurrentInputConnection();
         if (ic != null) {
             rememberReplacedWord(suggestion);
-            // If text is in correction mode and we're not using composing
-            // text to underline, then the word at the cursor position needs
-            // to be removed before committing the correction
-            if (correcting && !MODIFY_TEXT_FOR_CORRECTION) {
-                if (mLastSelectionStart < mLastSelectionEnd) {
-                    ic.setSelection(mLastSelectionStart, mLastSelectionStart);
-                }
-                EditingUtil.deleteWordAtCursor(ic, getWordSeparators());
-            }
-
             ic.commitText(suggestion, 1);
         }
         saveWordInHistory(suggestion);
@@ -1864,96 +1867,108 @@ public class LatinIME extends InputMethodService
         updateShiftKeyState(getCurrentInputEditorInfo());
     }
 
+    /**
+     * Tries to apply any voice alternatives for the word if this was a spoken word and
+     * there are voice alternatives.
+     * @param touching The word that the cursor is touching, with position information
+     * @return true if an alternative was found, false otherwise.
+     */
+    private boolean applyVoiceAlternatives(EditingUtil.SelectedWord touching) {
+        // Search for result in spoken word alternatives
+        String selectedWord = touching.word.toString().trim();
+        if (!mWordToSuggestions.containsKey(selectedWord)) {
+            selectedWord = selectedWord.toLowerCase();
+        }
+        if (mWordToSuggestions.containsKey(selectedWord)) {
+            mShowingVoiceSuggestions = true;
+            List<CharSequence> suggestions = mWordToSuggestions.get(selectedWord);
+            // If the first letter of touching is capitalized, make all the suggestions
+            // start with a capital letter.
+            if (Character.isUpperCase((char) touching.word.charAt(0))) {
+                for (int i = 0; i < suggestions.size(); i++) {
+                    String origSugg = (String) suggestions.get(i);
+                    String capsSugg = origSugg.toUpperCase().charAt(0)
+                            + origSugg.subSequence(1, origSugg.length()).toString();
+                    suggestions.set(i, capsSugg);
+                }
+            }
+            setSuggestions(suggestions, false, true, true);
+            setCandidatesViewShown(true);
+            return true;
+        }
+        return false;
+    }
+
+    /**
+     * Tries to apply any typed alternatives for the word if we have any cached alternatives,
+     * otherwise tries to find new corrections and completions for the word.
+     * @param touching The word that the cursor is touching, with position information
+     * @return true if an alternative was found, false otherwise.
+     */
+    private boolean applyTypedAlternatives(EditingUtil.SelectedWord touching) {
+        // If we didn't find a match, search for result in typed word history
+        WordComposer foundWord = null;
+        WordAlternatives alternatives = null;
+        for (WordAlternatives entry : mWordHistory) {
+            if (TextUtils.equals(entry.getChosenWord(), touching.word)) {
+                if (entry instanceof TypedWordAlternatives) {
+                    foundWord = ((TypedWordAlternatives) entry).word;
+                }
+                alternatives = entry;
+                break;
+            }
+        }
+        // If we didn't find a match, at least suggest completions
+        if (foundWord == null
+                && (mSuggest.isValidWord(touching.word)
+                        || mSuggest.isValidWord(touching.word.toString().toLowerCase()))) {
+            foundWord = new WordComposer();
+            for (int i = 0; i < touching.word.length(); i++) {
+                foundWord.add(touching.word.charAt(i), new int[] {
+                    touching.word.charAt(i)
+                });
+            }
+            foundWord.setCapitalized(Character.isUpperCase(touching.word.charAt(0)));
+        }
+        // Found a match, show suggestions
+        if (foundWord != null || alternatives != null) {
+            if (alternatives == null) {
+                alternatives = new TypedWordAlternatives(touching.word, foundWord);
+            }
+            showCorrections(alternatives);
+            if (foundWord != null) {
+                mWord = new WordComposer(foundWord);
+            } else {
+                mWord.reset();
+            }
+            return true;
+        }
+        return false;
+    }
+
     private void setOldSuggestions() {
-        // TODO: Inefficient to check if touching word and then get the touching word. Do it
-        // in one go.
         mShowingVoiceSuggestions = false;
+        if (mCandidateView != null && mCandidateView.isShowingAddToDictionaryHint()) {
+            return;
+        }
         InputConnection ic = getCurrentInputConnection();
         if (ic == null) return;
-        ic.beginBatchEdit();
-        // If there is a selection, then undo the selection first. Unfortunately this causes
-        // a flicker. TODO: Add getSelectionText() to InputConnection API.
-        if (mLastSelectionStart < mLastSelectionEnd) {
-            ic.setSelection(mLastSelectionStart, mLastSelectionStart);
-        }
-        if (!mPredicting && isCursorTouchingWord()) {
-            EditingUtil.Range range = new EditingUtil.Range();
-            CharSequence touching = EditingUtil.getWordAtCursor(getCurrentInputConnection(),
-                    mWordSeparators, range);
-            // If it's a selection, check if it's an entire word and no more, no less.
-            boolean fullword = EditingUtil.isFullWordOrInside(range, mLastSelectionStart,
-                    mLastSelectionEnd);
-            if (fullword && touching != null && touching.length() > 1) {
-                // Strip out any trailing word separator
-                if (mWordSeparators.indexOf(touching.charAt(touching.length() - 1)) > 0) {
-                    touching = touching.toString().substring(0, touching.length() - 1);
-                }
+        if (!mPredicting) {
+            // Extract the selected or touching text
+            EditingUtil.SelectedWord touching = EditingUtil.getWordAtCursorOrSelection(ic,
+                    mLastSelectionStart, mLastSelectionEnd, mWordSeparators);
 
-                // Search for result in spoken word alternatives
-                String selectedWord = touching.toString().trim();
-                if (!mWordToSuggestions.containsKey(selectedWord)){
-                    selectedWord = selectedWord.toLowerCase();
-                }
-                if (mWordToSuggestions.containsKey(selectedWord)){
-                    mShowingVoiceSuggestions = true;
-                    underlineWord(touching, range.charsBefore, range.charsAfter);
-                    List<CharSequence> suggestions = mWordToSuggestions.get(selectedWord);
-                    // If the first letter of touching is capitalized, make all the suggestions
-                    // start with a capital letter.
-                    if (Character.isUpperCase((char) touching.charAt(0))) {
-                        for (int i=0; i< suggestions.size(); i++) {
-                            String origSugg = (String) suggestions.get(i);
-                            String capsSugg = origSugg.toUpperCase().charAt(0)
-                                + origSugg.subSequence(1, origSugg.length()).toString();
-                            suggestions.set(i,capsSugg);
-                        }
-                    }
-                    setSuggestions(suggestions, false, true, true);
-                    setCandidatesViewShown(true);
-                    TextEntryState.selectedForCorrection();
-                    ic.endBatchEdit();
-                    return;
-                }
+            if (touching != null && touching.word.length() > 1) {
+                ic.beginBatchEdit();
 
-                // If we didn't find a match, search for result in typed word history
-                WordComposer foundWord = null;
-                WordAlternatives alternatives = null;
-                for (WordAlternatives entry : mWordHistory) {
-                    if (TextUtils.equals(entry.getChosenWord(), touching)) {
-                        if (entry instanceof TypedWordAlternatives) {
-                            foundWord = ((TypedWordAlternatives)entry).word;
-                        }
-                        alternatives = entry;
-                        break;
-                    }
-                }
-                // If we didn't find a match, at least suggest completions
-                if (foundWord == null && mSuggest.isValidWord(touching)) {
-                    foundWord = new WordComposer();
-                    for (int i = 0; i < touching.length(); i++) {
-                        foundWord.add(touching.charAt(i), new int[] { touching.charAt(i) });
-                    }
-                }
-                // Found a match, show suggestions
-                if (foundWord != null || alternatives != null) {
-                    underlineWord(touching, range.charsBefore, range.charsAfter);
+                if (!applyVoiceAlternatives(touching) && !applyTypedAlternatives(touching)) {
+                    abortCorrection(true);
+                } else {
                     TextEntryState.selectedForCorrection();
-                    if (alternatives == null) alternatives = new TypedWordAlternatives(touching,
-                            foundWord);
-                    showCorrections(alternatives);
-                    if (foundWord != null) {
-                        mWord = new WordComposer(foundWord);
-                    } else {
-                        mWord.reset();
-                    }
-                    // Revert the selection
-                    if (mLastSelectionStart < mLastSelectionEnd) {
-                        ic.setSelection(mLastSelectionStart, mLastSelectionEnd);
-                    }
-                    ic.endBatchEdit();
-                    return;
+                    EditingUtil.underlineWord(ic, touching);
                 }
-                abortCorrection(true);
+
+                ic.endBatchEdit();
             } else {
                 abortCorrection(true);
                 setNextSuggestions();
@@ -1961,28 +1976,12 @@ public class LatinIME extends InputMethodService
         } else {
             abortCorrection(true);
         }
-        // Revert the selection
-        if (mLastSelectionStart < mLastSelectionEnd) {
-            ic.setSelection(mLastSelectionStart, mLastSelectionEnd);
-        }
-        ic.endBatchEdit();
     }
 
     private void setNextSuggestions() {
         setSuggestions(mSuggestPuncList, false, false, false);
     }
 
-    private void underlineWord(CharSequence word, int left, int right) {
-        InputConnection ic = getCurrentInputConnection();
-        if (ic == null) return;
-        if (MODIFY_TEXT_FOR_CORRECTION) {
-            ic.finishComposingText();
-            ic.deleteSurroundingText(left, right);
-            ic.setComposingText(word, 1);
-        }
-        ic.setSelection(mLastSelectionStart, mLastSelectionStart);
-    }
-
     private void addToDictionaries(CharSequence suggestion, int frequencyDelta) {
         checkAddToDictionary(suggestion, frequencyDelta, false);
     }