Minor changes in SpellCheckSpan pool management in SpellChecker

Bug 6464190

The 'inProgress' flag is set to false when the SpellCheckSpan starts
to get used (instead of a less intuitive when it is removed).

Pool recycling in handled by onSpellCheckSpanRemoved, called from
the TextView's SpanWatcher, when a SpellCheckSpan is removed for any
reason (from the SC code or due to text editing).

The other change is that Sentence SC now correctly removes the span
from the text (and hence recycles it in the pool).

Change-Id: If8b433fd5e41d4dc0304a127ebcc088ea1eecaa7

Author: Gilles Debunne

core/java/android/widget/SpellChecker.java

@@ -132,8 +132,6 @@ private void resetSession() {
 
         // Restore SpellCheckSpans in pool
         for (int i = 0; i < mLength; i++) {
-            // Resets id and progress to invalidate spell check span
-            mSpellCheckSpans[i].setSpellCheckInProgress(false);
             mIds[i] = -1;
         }
         mLength = 0;
@@ -200,15 +198,16 @@ private int nextSpellCheckSpanIndex() {
 
     private void addSpellCheckSpan(Editable editable, int start, int end) {
         final int index = nextSpellCheckSpanIndex();
-        editable.setSpan(mSpellCheckSpans[index], start, end, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
+        SpellCheckSpan spellCheckSpan = mSpellCheckSpans[index];
+        editable.setSpan(spellCheckSpan, start, end, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
+        spellCheckSpan.setSpellCheckInProgress(false);
         mIds[index] = mSpanSequenceCounter++;
     }
 
-    public void removeSpellCheckSpan(SpellCheckSpan spellCheckSpan) {
+    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) {
-                // Resets id and progress to invalidate spell check span
-                mSpellCheckSpans[i].setSpellCheckInProgress(false);
                 mIds[i] = -1;
                 return;
             }
@@ -357,6 +356,7 @@ public void onGetSuggestions(SuggestionsInfo[] results) {
             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);
             }
         }
@@ -384,11 +384,12 @@ public void onGetSentenceSuggestions(SentenceSuggestionsInfo[] results) {
                         suggestionsInfo, offset, length);
                 if (spellCheckSpan == null && scs != null) {
                     // the spellCheckSpan is shared by all the "SuggestionsInfo"s in the same
-                    // SentenceSuggestionsInfo
+                    // SentenceSuggestionsInfo. Removal is deferred after this loop.
                     spellCheckSpan = scs;
                 }
             }
             if (spellCheckSpan != null) {
+                // onSpellCheckSpanRemoved will recycle this span in the pool
                 editable.removeSpan(spellCheckSpan);
             }
         }
@@ -595,7 +596,8 @@ public void parse() {
                             }
                             break;
                         }
-                        removeSpellCheckSpan(spellCheckSpan);
+                        // This spellCheckSpan is replaced by the one we are creating
+                        editable.removeSpan(spellCheckSpan);
                         spellCheckStart = Math.min(spanStart, spellCheckStart);
                         spellCheckEnd = Math.max(spanEnd, spellCheckEnd);
                     }

core/java/android/widget/TextView.java

@@ -7214,7 +7214,7 @@ void spanChange(Spanned buf, Object what, int oldStart, int newStart, int oldEnd
 
         if (mEditor != null && mEditor.mSpellChecker != null && newStart < 0 &&
                 what instanceof SpellCheckSpan) {
-            mEditor.mSpellChecker.removeSpellCheckSpan((SpellCheckSpan) what);
+            mEditor.mSpellChecker.onSpellCheckSpanRemoved((SpellCheckSpan) what);
         }
     }