Fix getLineRight()/getLineLeft() may compute leadingMargin twice (7425d982) · Commits · e / os / android_frameworks_base

core/java/android/text/Layout.java

+71 −42

Original line number	Diff line number	Diff line
		@@ -1269,29 +1269,47 @@ public abstract class Layout {
		* scrolling on the specified line.
		*/
		public float getLineLeft(int line) {
		int dir = getParagraphDirection(line);
		Alignment align = getParagraphAlignment(line);
		final int dir = getParagraphDirection(line);
		final Alignment align = getParagraphAlignment(line);

		if (align == Alignment.ALIGN_LEFT) {
		return 0;
		} else if (align == Alignment.ALIGN_NORMAL) {
		if (dir == DIR_RIGHT_TO_LEFT)
		return getParagraphRight(line) - getLineMax(line);
		else
		return 0;
		} else if (align == Alignment.ALIGN_RIGHT) {
		// First convert combinations of alignment and direction settings to
		// three basic cases: ALIGN_LEFT, ALIGN_RIGHT and ALIGN_CENTER.
		// For unexpected cases, it will fallback to ALIGN_LEFT.
		final Alignment resultAlign;
		switch(align) {
		case ALIGN_NORMAL:
		resultAlign =
		dir == DIR_RIGHT_TO_LEFT ? Alignment.ALIGN_RIGHT : Alignment.ALIGN_LEFT;
		break;
		case ALIGN_OPPOSITE:
		resultAlign =
		dir == DIR_RIGHT_TO_LEFT ? Alignment.ALIGN_LEFT : Alignment.ALIGN_RIGHT;
		break;
		case ALIGN_CENTER:
		resultAlign = Alignment.ALIGN_CENTER;
		break;
		case ALIGN_RIGHT:
		resultAlign = Alignment.ALIGN_RIGHT;
		break;
		default: /* align == Alignment.ALIGN_LEFT */
		resultAlign = Alignment.ALIGN_LEFT;
		}

		// Here we must use getLineMax() to do the computation, because it maybe overridden by
		// derived class. And also note that line max equals the width of the text in that line
		// plus the leading margin.
		switch (resultAlign) {
		case ALIGN_CENTER:
		final int left = getParagraphLeft(line);
		final float max = getLineMax(line);
		// This computation only works when mWidth equals leadingMargin plus
		// the width of text in this line. If this condition doesn't meet anymore,
		// please change here too.
		return (float) Math.floor(left + (mWidth - max) / 2);
		case ALIGN_RIGHT:
		return mWidth - getLineMax(line);
		} else if (align == Alignment.ALIGN_OPPOSITE) {
		if (dir == DIR_RIGHT_TO_LEFT)
		default: /* resultAlign == Alignment.ALIGN_LEFT */
		return 0;
		else
		return mWidth - getLineMax(line);
		} else { /* align == Alignment.ALIGN_CENTER */
		int left = getParagraphLeft(line);
		int right = getParagraphRight(line);
		int max = ((int) getLineMax(line)) & ~1;

		return left + ((right - left) - max) / 2;
		}
		}

		@@ -1300,29 +1318,40 @@ public abstract class Layout {
		* scrolling on the specified line.
		*/
		public float getLineRight(int line) {
		int dir = getParagraphDirection(line);
		Alignment align = getParagraphAlignment(line);
		final int dir = getParagraphDirection(line);
		final Alignment align = getParagraphAlignment(line);

		if (align == Alignment.ALIGN_LEFT) {
		return getParagraphLeft(line) + getLineMax(line);
		} else if (align == Alignment.ALIGN_NORMAL) {
		if (dir == DIR_RIGHT_TO_LEFT)
		return mWidth;
		else
		return getParagraphLeft(line) + getLineMax(line);
		} else if (align == Alignment.ALIGN_RIGHT) {
		final Alignment resultAlign;
		switch(align) {
		case ALIGN_NORMAL:
		resultAlign =
		dir == DIR_RIGHT_TO_LEFT ? Alignment.ALIGN_RIGHT : Alignment.ALIGN_LEFT;
		break;
		case ALIGN_OPPOSITE:
		resultAlign =
		dir == DIR_RIGHT_TO_LEFT ? Alignment.ALIGN_LEFT : Alignment.ALIGN_RIGHT;
		break;
		case ALIGN_CENTER:
		resultAlign = Alignment.ALIGN_CENTER;
		break;
		case ALIGN_RIGHT:
		resultAlign = Alignment.ALIGN_RIGHT;
		break;
		default: /* align == Alignment.ALIGN_LEFT */
		resultAlign = Alignment.ALIGN_LEFT;
		}

		switch (resultAlign) {
		case ALIGN_CENTER:
		final int right = getParagraphRight(line);
		final float max = getLineMax(line);
		// This computation only works when mWidth equals leadingMargin plus width of the
		// text in this line. If this condition doesn't meet anymore, please change here.
		return (float) Math.ceil(right - (mWidth - max) / 2);
		case ALIGN_RIGHT:
		return mWidth;
		} else if (align == Alignment.ALIGN_OPPOSITE) {
		if (dir == DIR_RIGHT_TO_LEFT)
		default: /* resultAlign == Alignment.ALIGN_LEFT */
		return getLineMax(line);
		else
		return mWidth;
		} else { /* align == Alignment.ALIGN_CENTER */
		int left = getParagraphLeft(line);
		int right = getParagraphRight(line);
		int max = ((int) getLineMax(line)) & ~1;

		return right - ((right - left) - max) / 2;
		}
		}

		@@ -1671,7 +1700,7 @@ public abstract class Layout {
		* Return the vertical position of the baseline of the specified line.
		*/
		public final int getLineBaseline(int line) {
		// getLineTop(line+1) == getLineTop(line)
		// getLineTop(line+1) == getLineBottom(line)
		return getLineTop(line+1) - getLineDescent(line);
		}