Merge "Text selection: Fix word boundaries for languages without spaces" into mnc-dev

core/java/android/text/method/WordIterator.java

@@ -147,24 +147,13 @@ public class WordIterator implements Selection.PositionIterator {
      * @throws IllegalArgumentException is offset is not valid.
      */
     public int getBeginning(int offset) {
-        final int shiftedOffset = offset - mOffsetShift;
+        // TODO: Check if usage of this can be updated to getBeginning(offset, true) if
-        checkOffsetIsValid(shiftedOffset);
+        // so this method can be removed.
-
+        return getBeginning(offset, false);
-        if (isOnLetterOrDigit(shiftedOffset)) {
-            if (mIterator.isBoundary(shiftedOffset)) {
-                return shiftedOffset + mOffsetShift;
-            } else {
-                return mIterator.preceding(shiftedOffset) + mOffsetShift;
-            }
-        } else {
-            if (isAfterLetterOrDigit(shiftedOffset)) {
-                return mIterator.preceding(shiftedOffset) + mOffsetShift;
-            }
-        }
-        return BreakIterator.DONE;
     }
 
-    /** If <code>offset</code> is within a word, returns the index of the last character of that
+    /**
+     * If <code>offset</code> is within a word, returns the index of the last character of that
      * word plus one, otherwise returns BreakIterator.DONE.
      *
      * The offsets that are considered to be part of a word are the indexes of its characters,
@@ -177,11 +166,106 @@ public class WordIterator implements Selection.PositionIterator {
      * @throws IllegalArgumentException is offset is not valid.
      */
     public int getEnd(int offset) {
+        // TODO: Check if usage of this can be updated to getEnd(offset, true), if
+        // so this method can be removed.
+        return getEnd(offset, false);
+    }
+
+    /**
+     * If the <code>offset</code> is within a word or on a word boundary that can only be
+     * considered the start of a word (e.g. _word where "_" is any character that would not
+     * be considered part of the word) then this returns the index of the first character of
+     * that word.
+     *
+     * If the offset is on a word boundary that can be considered the start and end of a
+     * word, e.g. AABB (where AA and BB are both words) and the offset is the boundary
+     * between AA and BB, this would return the start of the previous word, AA.
+     *
+     * Returns BreakIterator.DONE if there is no previous boundary.
+     *
+     * @throws IllegalArgumentException is offset is not valid.
+     */
+    public int getPrevWordBeginningOnTwoWordsBoundary(int offset) {
+        return getBeginning(offset, true);
+    }
+
+    /**
+     * If the <code>offset</code> is within a word or on a word boundary that can only be
+     * considered the end of a word (e.g. word_ where "_" is any character that would not
+     * be considered part of the word) then this returns the index of the last character
+     * plus one of that word.
+     *
+     * If the offset is on a word boundary that can be considered the start and end of a
+     * word, e.g. AABB (where AA and BB are both words) and the offset is the boundary
+     * between AA and BB, this would return the end of the next word, BB.
+     *
+     * Returns BreakIterator.DONE if there is no next boundary.
+     *
+     * @throws IllegalArgumentException is offset is not valid.
+     */
+    public int getNextWordEndOnTwoWordBoundary(int offset) {
+        return getEnd(offset, true);
+    }
+
+    /**
+     * If the <code>offset</code> is within a word or on a word boundary that can only be
+     * considered the start of a word (e.g. _word where "_" is any character that would not
+     * be considered part of the word) then this returns the index of the first character of
+     * that word.
+     *
+     * If the offset is on a word boundary that can be considered the start and end of a
+     * word, e.g. AABB (where AA and BB are both words) and the offset is the boundary
+     * between AA and BB, and getPrevWordBeginningOnTwoWordsBoundary is true then this would
+     * return the start of the previous word, AA. Otherwise it would return the current offset,
+     * the start of BB.
+     *
+     * Returns BreakIterator.DONE if there is no previous boundary.
+     *
+     * @throws IllegalArgumentException is offset is not valid.
+     */
+    private int getBeginning(int offset, boolean getPrevWordBeginningOnTwoWordsBoundary) {
+        final int shiftedOffset = offset - mOffsetShift;
+        checkOffsetIsValid(shiftedOffset);
+
+        if (isOnLetterOrDigit(shiftedOffset)) {
+            if (mIterator.isBoundary(shiftedOffset)
+                    && (!isAfterLetterOrDigit(shiftedOffset)
+                            || !getPrevWordBeginningOnTwoWordsBoundary)) {
+                return shiftedOffset + mOffsetShift;
+            } else {
+                return mIterator.preceding(shiftedOffset) + mOffsetShift;
+            }
+        } else {
+            if (isAfterLetterOrDigit(shiftedOffset)) {
+                return mIterator.preceding(shiftedOffset) + mOffsetShift;
+            }
+        }
+        return BreakIterator.DONE;
+    }
+
+    /**
+     * If the <code>offset</code> is within a word or on a word boundary that can only be
+     * considered the end of a word (e.g. word_ where "_" is any character that would not be
+     * considered part of the word) then this returns the index of the last character plus one
+     * of that word.
+     *
+     * If the offset is on a word boundary that can be considered the start and end of a
+     * word, e.g. AABB (where AA and BB are both words) and the offset is the boundary
+     * between AA and BB, and getNextWordEndOnTwoWordBoundary is true then this would return
+     * the end of the next word, BB. Otherwise it would return the current offset, the end
+     * of AA.
+     *
+     * Returns BreakIterator.DONE if there is no next boundary.
+     *
+     * @throws IllegalArgumentException is offset is not valid.
+     */
+    private int getEnd(int offset, boolean getNextWordEndOnTwoWordBoundary) {
         final int shiftedOffset = offset - mOffsetShift;
         checkOffsetIsValid(shiftedOffset);
 
         if (isAfterLetterOrDigit(shiftedOffset)) {
-            if (mIterator.isBoundary(shiftedOffset)) {
+            if (mIterator.isBoundary(shiftedOffset)
+                    && (!isOnLetterOrDigit(shiftedOffset) || !getNextWordEndOnTwoWordBoundary)) {
                 return shiftedOffset + mOffsetShift;
             } else {
                 return mIterator.following(shiftedOffset) + mOffsetShift;

core/java/android/widget/Editor.java

@@ -123,6 +123,7 @@ public class Editor {
     private static final float[] TEMP_POSITION = new float[2];
     private static int DRAG_SHADOW_MAX_TEXT_LENGTH = 20;
     private static final float LINE_SLOP_MULTIPLIER_FOR_HANDLEVIEWS = 0.5f;
+    private static final int UNSET_X_VALUE = -1;
     // Tag used when the Editor maintains its own separate UndoManager.
     private static final String UNDO_OWNER_TAG = "Editor";
 
@@ -735,7 +736,7 @@ public class Editor {
             retOffset = getWordIteratorWithText().getPunctuationBeginning(offset);
         } else {
             // Not on a punctuation boundary, find the word start.
-            retOffset = getWordIteratorWithText().getBeginning(offset);
+            retOffset = getWordIteratorWithText().getPrevWordBeginningOnTwoWordsBoundary(offset);
         }
         if (retOffset == BreakIterator.DONE) {
             return offset;
@@ -750,7 +751,7 @@ public class Editor {
             retOffset = getWordIteratorWithText().getPunctuationEnd(offset);
         } else {
             // Not on a punctuation boundary, find the word end.
-            retOffset = getWordIteratorWithText().getEnd(offset);
+            retOffset = getWordIteratorWithText().getNextWordEndOnTwoWordBoundary(offset);
         }
         if (retOffset == BreakIterator.DONE) {
             return offset;
@@ -4067,6 +4068,10 @@ public class Editor {
         private boolean mInWord = false;
         // Difference between touch position and word boundary position.
         private float mTouchWordDelta;
+        // X value of the previous updatePosition call.
+        private float mPrevX;
+        // Indicates if the handle has moved a boundary between LTR and RTL text.
+        private boolean mLanguageDirectionChanged = false;
 
         public SelectionStartHandleView(Drawable drawableLtr, Drawable drawableRtl) {
             super(drawableLtr, drawableRtl);
@@ -4127,7 +4132,43 @@ public class Editor {
             int end = getWordEnd(offset);
             int start = getWordStart(offset);
 
-            if (offset < mPreviousOffset) {
+            if (mPrevX == UNSET_X_VALUE) {
+                mPrevX = x;
+            }
+
+            final int selectionStart = mTextView.getSelectionStart();
+            final boolean selectionStartRtl = layout.isRtlCharAt(selectionStart);
+            final boolean atRtl = layout.isRtlCharAt(offset);
+            final boolean isLvlBoundary = layout.isLevelBoundary(offset);
+            boolean isExpanding;
+
+            // We can't determine if the user is expanding or shrinking the selection if they're
+            // on a bi-di boundary, so until they've moved past the boundary we'll just place
+            // the cursor at the current position.
+            if (isLvlBoundary || (selectionStartRtl && !atRtl) || (!selectionStartRtl && atRtl)) {
+                // We're on a boundary or this is the first direction change -- just update
+                // to the current position.
+                mLanguageDirectionChanged = true;
+                mTouchWordDelta = 0.0f;
+                positionAtCursorOffset(offset, false);
+                return;
+            } else if (mLanguageDirectionChanged && !isLvlBoundary) {
+                // We've just moved past the boundary so update the position. After this we can
+                // figure out if the user is expanding or shrinking to go by word or character.
+                positionAtCursorOffset(offset, false);
+                mTouchWordDelta = 0.0f;
+                mLanguageDirectionChanged = false;
+                return;
+            } else {
+                final float xDiff = x - mPrevX;
+                if (atRtl) {
+                    isExpanding = xDiff > 0 || currLine > mPrevLine;
+                } else {
+                    isExpanding = xDiff < 0 || currLine < mPrevLine;
+                }
+            }
+
+            if (isExpanding) {
                 // User is increasing the selection.
                 if (!mInWord || currLine < mPrevLine) {
                     // We're not in a word, or we're on a different line so we'll expand by
@@ -4182,6 +4223,7 @@ public class Editor {
                 }
                 positionAtCursorOffset(offset, false);
             }
+            mPrevX = x;
         }
 
         @Override
@@ -4196,6 +4238,7 @@ public class Editor {
             if (event.getActionMasked() == MotionEvent.ACTION_UP) {
                 // Reset the touch word offset when the user has lifted their finger.
                 mTouchWordDelta = 0.0f;
+                mPrevX = UNSET_X_VALUE;
             }
             return superResult;
         }
@@ -4206,6 +4249,10 @@ public class Editor {
         private boolean mInWord = false;
         // Difference between touch position and word boundary position.
         private float mTouchWordDelta;
+        // X value of the previous updatePosition call.
+        private float mPrevX;
+        // Indicates if the handle has moved a boundary between LTR and RTL text.
+        private boolean mLanguageDirectionChanged = false;
 
         public SelectionEndHandleView(Drawable drawableLtr, Drawable drawableRtl) {
             super(drawableLtr, drawableRtl);
@@ -4266,7 +4313,43 @@ public class Editor {
             int end = getWordEnd(offset);
             int start = getWordStart(offset);
 
-            if (offset > mPreviousOffset) {
+            if (mPrevX == UNSET_X_VALUE) {
+                mPrevX = x;
+            }
+
+            final int selectionEnd = mTextView.getSelectionEnd();
+            final boolean selectionEndRtl = layout.isRtlCharAt(selectionEnd);
+            final boolean atRtl = layout.isRtlCharAt(offset);
+            final boolean isLvlBoundary = layout.isLevelBoundary(offset);
+            boolean isExpanding;
+
+            // We can't determine if the user is expanding or shrinking the selection if they're
+            // on a bi-di boundary, so until they've moved past the boundary we'll just place
+            // the cursor at the current position.
+            if (isLvlBoundary || (selectionEndRtl && !atRtl) || (!selectionEndRtl && atRtl)) {
+                // We're on a boundary or this is the first direction change -- just update
+                // to the current position.
+                mLanguageDirectionChanged = true;
+                mTouchWordDelta = 0.0f;
+                positionAtCursorOffset(offset, false);
+                return;
+            } else if (mLanguageDirectionChanged && !isLvlBoundary) {
+                // We've just moved past the boundary so update the position. After this we can
+                // figure out if the user is expanding or shrinking to go by word or character.
+                positionAtCursorOffset(offset, false);
+                mTouchWordDelta = 0.0f;
+                mLanguageDirectionChanged = false;
+                return;
+            } else {
+                final float xDiff = x - mPrevX;
+                if (atRtl) {
+                    isExpanding = xDiff < 0 || currLine < mPrevLine;
+                } else {
+                    isExpanding = xDiff > 0 || currLine > mPrevLine;
+                }
+            }
+
+            if (isExpanding) {
                 // User is increasing the selection.
                 if (!mInWord || currLine > mPrevLine) {
                     // We're not in a word, or we're on a different line so we'll expand by
@@ -4321,6 +4404,7 @@ public class Editor {
                 }
                 positionAtCursorOffset(offset, false);
             }
+            mPrevX = x;
         }
 
         @Override
@@ -4335,6 +4419,7 @@ public class Editor {
             if (event.getActionMasked() == MotionEvent.ACTION_UP) {
                 // Reset the touch word offset when the user has lifted their finger.
                 mTouchWordDelta = 0.0f;
+                mPrevX = UNSET_X_VALUE;
             }
             return superResult;
         }