Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 9c68b29c authored by Keisuke Kuroyanagi's avatar Keisuke Kuroyanagi
Browse files

Fix: A part of grapheme cluster can be selected. 

Previously, when a selection handle is about to pass the other
handle, the offset of the handle was computed with +1 or -1 to
the offset, without considering UTF-16 surrogate pairs or grapheme
clusters. This patch consistently uses grapheme clusters to compute
the new offset in such cases.

Bug: 20112392
Change-Id: I2b5e206d20886ca7ceb9f4375ee0d66f2328f99d
parent e48cca2a

core/java/android/widget/Editor.java

+17 −21
Original line number Original line Diff line number Diff line
@@ -813,7 +813,7 @@ public class Editor { 
            if (selectionStart == BreakIterator.DONE || selectionEnd == BreakIterator.DONE ||

            if (selectionStart == BreakIterator.DONE || selectionEnd == BreakIterator.DONE ||

                    selectionStart == selectionEnd) {

                    selectionStart == selectionEnd) {

                // Possible when the word iterator does not properly handle the text's language

                // Possible when the word iterator does not properly handle the text's language

                long range = getCharRange(minOffset);

                long range = getCharClusterRange(minOffset);

                selectionStart = TextUtils.unpackRangeStartFromLong(range);

                selectionStart = TextUtils.unpackRangeStartFromLong(range);

                selectionEnd = TextUtils.unpackRangeEndFromLong(range);

                selectionEnd = TextUtils.unpackRangeEndFromLong(range);

            }

            }
@@ -856,27 +856,23 @@ public class Editor { 
        return mWordIteratorWithText;

        return mWordIteratorWithText;

    }

    }





    private long getCharRange(int offset) {

    private int getNextCursorOffset(int offset, boolean findAfterGivenOffset) {

        final int textLength = mTextView.getText().length();

        final Layout layout = mTextView.getLayout();

        if (offset + 1 < textLength) {

        if (layout == null) return offset;

            final char currentChar = mTextView.getText().charAt(offset);

        final CharSequence text = mTextView.getText();

            final char nextChar = mTextView.getText().charAt(offset + 1);

        final int nextOffset = layout.getPaint().getTextRunCursor(text, 0, text.length(),

            if (Character.isSurrogatePair(currentChar, nextChar)) {

                layout.isRtlCharAt(offset) ? Paint.DIRECTION_RTL : Paint.DIRECTION_LTR,

                return TextUtils.packRangeInLong(offset,  offset + 2);

                offset, findAfterGivenOffset ? Paint.CURSOR_AFTER : Paint.CURSOR_BEFORE);

            }

        return nextOffset == -1 ? offset : nextOffset;

    }

    }



    private long getCharClusterRange(int offset) {

        final int textLength = mTextView.getText().length();

        if (offset < textLength) {

        if (offset < textLength) {

            return TextUtils.packRangeInLong(offset,  offset + 1);

            return TextUtils.packRangeInLong(offset, getNextCursorOffset(offset, true));

        }

        if (offset - 2 >= 0) {

            final char previousChar = mTextView.getText().charAt(offset - 1);

            final char previousPreviousChar = mTextView.getText().charAt(offset - 2);

            if (Character.isSurrogatePair(previousPreviousChar, previousChar)) {

                return TextUtils.packRangeInLong(offset - 2,  offset);

            }

        }

        }

        if (offset - 1 >= 0) {

        if (offset - 1 >= 0) {

            return TextUtils.packRangeInLong(offset - 1,  offset);

            return TextUtils.packRangeInLong(getNextCursorOffset(offset, false), offset);

        }

        }

        return TextUtils.packRangeInLong(offset, offset);

        return TextUtils.packRangeInLong(offset, offset);

    }

    }
@@ -3972,7 +3968,7 @@ public class Editor { 
                    int alteredOffset = mTextView.getOffsetAtCoordinate(mPrevLine, x);

                    int alteredOffset = mTextView.getOffsetAtCoordinate(mPrevLine, x);

                    if (alteredOffset >= selectionEnd) {

                    if (alteredOffset >= selectionEnd) {

                        // Can't pass the other drag handle.

                        // Can't pass the other drag handle.

                        offset = Math.max(0, selectionEnd - 1);

                        offset = getNextCursorOffset(selectionEnd, false);

                    } else {

                    } else {

                        offset = alteredOffset;

                        offset = alteredOffset;

                    }

                    }
@@ -4075,7 +4071,7 @@ public class Editor { 
                    int length = mTextView.getText().length();

                    int length = mTextView.getText().length();

                    if (alteredOffset <= selectionStart) {

                    if (alteredOffset <= selectionStart) {

                        // Can't pass the other drag handle.

                        // Can't pass the other drag handle.

                        offset = Math.min(selectionStart + 1, length);

                        offset = getNextCursorOffset(selectionStart, true);

                    } else {

                    } else {

                        offset = Math.min(alteredOffset, length);

                        offset = Math.min(alteredOffset, length);

                    }

                    }