Make ellipsize retry if text doesn't fit
This fixes the cases where the replacement of parts of text with
ellipsis may result in more-than-expected width of text due to
contextual width changes in the font, such as kerning or Arabic
shaping.
The calculations in TextUtils.ellipsize() and StaticLayout are fixed
to recalculate the new width and reduce it further until the text
actuall fits. BoringLayout and DynamicLayout get fixed too since
they use the other two implementations indirectly.
Also reverse a recently-introduced incorrect check for
multi-character ellipsis in Layout.java.
Fixes: 31537595
Fixes: 64156587
Test: Manual (Arabic edge cases ellipsize correctly)
Test: bit CtsTextTestCases:*
Test: bit CtsWidgetTestCases:android.widget.cts.TextViewTest
Test: bit CtsWidgetTestCases:android.widget.cts.EditTextTest
Test: bit CtsWidgetTestCases:android.widget.cts.CheckedTextViewTest
Test: bit CtsWidgetTestCases:android.widget.cts.AutoCompleteTextViewTest
Test: bit CtsWidgetTestCases:android.widget.cts.MultiAutoCompleteTextViewTest
Test: bit FrameworksCoreTests:android.text.
Test: adb shell am instrument -w com.android.documentsui.tests/android.support.test.runner.AndroidJUnitRunner
Change-Id: Iaddcc8b01c78d477e2c29b339d321c9631426f34
diff --git a/core/java/android/text/StaticLayout.java b/core/java/android/text/StaticLayout.java
index 9ebf04d..a7be4dd 100644
--- a/core/java/android/text/StaticLayout.java
+++ b/core/java/android/text/StaticLayout.java
@@ -559,7 +559,7 @@
Builder.recycle(b);
}
- /* package */ StaticLayout(CharSequence text) {
+ /* package */ StaticLayout(@Nullable CharSequence text) {
super(text, null, 0, null, 0, 0);
mColumns = COLUMNS_ELLIPSIZE;
@@ -601,7 +601,7 @@
}
/* package */ void generate(Builder b, boolean includepad, boolean trackpad) {
- CharSequence source = b.mText;
+ final CharSequence source = b.mText;
int bufStart = b.mStart;
int bufEnd = b.mEnd;
TextPaint paint = b.mPaint;
@@ -722,7 +722,7 @@
// TODO: Support more justification mode, e.g. letter spacing, stretching.
b.mJustificationMode != Layout.JUSTIFICATION_MODE_NONE);
if (mLeftIndents != null || mRightIndents != null) {
- // TODO(raph) performance: it would be better to do this once per layout rather
+ // TODO(performance): it would be better to do this once per layout rather
// than once per paragraph, but that would require a change to the native
// interface.
int leftLen = mLeftIndents == null ? 0 : mLeftIndents.length;
@@ -809,7 +809,7 @@
width += widths[j];
}
}
- flag |= flags[i] & TAB_MASK;
+ flag |= flags[i] & TAB_MASK; // XXX May need to also have starting hyphen edit
}
// Treat the last line and overflowed lines as a single line.
breaks[remainingLineCount - 1] = breaks[breakCount - 1];
@@ -911,17 +911,16 @@
}
}
- private int out(CharSequence text, int start, int end,
- int above, int below, int top, int bottom, int v,
- float spacingmult, float spacingadd,
- LineHeightSpan[] chooseHt, int[] chooseHtv,
- Paint.FontMetricsInt fm, int flags,
- boolean needMultiply, byte[] chdirs, int dir,
- boolean easy, int bufEnd, boolean includePad,
- boolean trackPad, boolean addLastLineLineSpacing, char[] chs,
- float[] widths, int widthStart, TextUtils.TruncateAt ellipsize,
- float ellipsisWidth, float textWidth,
- TextPaint paint, boolean moreChars) {
+ // The parameters that are not changed in the method are marked as final to make the code
+ // easier to understand.
+ private int out(final CharSequence text, final int start, final int end, int above, int below,
+ int top, int bottom, int v, final float spacingmult, final float spacingadd,
+ final LineHeightSpan[] chooseHt, final int[] chooseHtv, final Paint.FontMetricsInt fm,
+ final int flags, final boolean needMultiply, final byte[] chdirs, final int dir,
+ final boolean easy, final int bufEnd, final boolean includePad, final boolean trackPad,
+ final boolean addLastLineLineSpacing, final char[] chs, final float[] widths,
+ final int widthStart, final TextUtils.TruncateAt ellipsize, final float ellipsisWidth,
+ final float textWidth, final TextPaint paint, final boolean moreChars) {
final int j = mLineCount;
final int off = j * mColumns;
final int want = off + mColumns + TOP;
@@ -941,30 +940,30 @@
mLineDirections = grow;
}
- if (chooseHt != null) {
- fm.ascent = above;
- fm.descent = below;
- fm.top = top;
- fm.bottom = bottom;
+ lines[off + START] = start;
+ lines[off + TOP] = v;
- for (int i = 0; i < chooseHt.length; i++) {
- if (chooseHt[i] instanceof LineHeightSpan.WithDensity) {
- ((LineHeightSpan.WithDensity) chooseHt[i]).
- chooseHeight(text, start, end, chooseHtv[i], v, fm, paint);
+ // Information about hyphenation, tabs, and directions are needed for determining
+ // ellipsization, so the values should be assigned before ellipsization.
- } else {
- chooseHt[i].chooseHeight(text, start, end, chooseHtv[i], v, fm);
- }
- }
+ // TODO: could move TAB to share same column as HYPHEN, simplifying this code and gaining
+ // one bit for start field
+ lines[off + TAB] |= flags & TAB_MASK;
+ lines[off + HYPHEN] = flags;
- above = fm.ascent;
- below = fm.descent;
- top = fm.top;
- bottom = fm.bottom;
+ lines[off + DIR] |= dir << DIR_SHIFT;
+ // easy means all chars < the first RTL, so no emoji, no nothing
+ // XXX a run with no text or all spaces is easy but might be an empty
+ // RTL paragraph. Make sure easy is false if this is the case.
+ if (easy) {
+ mLineDirections[j] = DIRS_ALL_LEFT_TO_RIGHT;
+ } else {
+ mLineDirections[j] = AndroidBidi.directions(dir, chdirs, start - widthStart, chs,
+ start - widthStart, end - start);
}
- boolean firstLine = (j == 0);
- boolean currentLineIsTheLastVisibleOne = (j + 1 == mMaximumVisibleLineCount);
+ final boolean firstLine = (j == 0);
+ final boolean currentLineIsTheLastVisibleOne = (j + 1 == mMaximumVisibleLineCount);
if (ellipsize != null) {
// If there is only one line, then do any type of ellipsis except when it is MARQUEE
@@ -977,9 +976,9 @@
(!firstLine && (currentLineIsTheLastVisibleOne || !moreChars) &&
ellipsize == TextUtils.TruncateAt.END);
if (doEllipsis) {
- calculateEllipsis(start, end, widths, widthStart,
- ellipsisWidth, ellipsize, j,
- textWidth, paint, forceEllipsis);
+ calculateEllipsis(text, start, end, widths, widthStart,
+ ellipsisWidth - getTotalInsets(j), ellipsize, j,
+ textWidth, paint, forceEllipsis, dir);
}
}
@@ -998,6 +997,28 @@
}
}
+ if (chooseHt != null) {
+ fm.ascent = above;
+ fm.descent = below;
+ fm.top = top;
+ fm.bottom = bottom;
+
+ for (int i = 0; i < chooseHt.length; i++) {
+ if (chooseHt[i] instanceof LineHeightSpan.WithDensity) {
+ ((LineHeightSpan.WithDensity) chooseHt[i])
+ .chooseHeight(text, start, end, chooseHtv[i], v, fm, paint);
+
+ } else {
+ chooseHt[i].chooseHeight(text, start, end, chooseHtv[i], v, fm);
+ }
+ }
+
+ above = fm.ascent;
+ below = fm.descent;
+ top = fm.top;
+ bottom = fm.bottom;
+ }
+
if (firstLine) {
if (trackPad) {
mTopPadding = top - above;
@@ -1008,8 +1029,6 @@
}
}
- int extra;
-
if (lastLine) {
if (trackPad) {
mBottomPadding = bottom - below;
@@ -1020,8 +1039,9 @@
}
}
+ final int extra;
if (needMultiply && (addLastLineLineSpacing || !lastLine)) {
- double ex = (below - above) * (spacingmult - 1) + spacingadd;
+ final double ex = (below - above) * (spacingmult - 1) + spacingadd;
if (ex >= 0) {
extra = (int)(ex + EXTRA_ROUNDING);
} else {
@@ -1031,8 +1051,6 @@
extra = 0;
}
- lines[off + START] = start;
- lines[off + TOP] = v;
lines[off + DESCENT] = below + extra;
lines[off + EXTRA] = extra;
@@ -1040,7 +1058,7 @@
// store the height as if it was ellipsized
if (!mEllipsized && currentLineIsTheLastVisibleOne) {
// below calculation as if it was the last line
- int maxLineBelow = includePad ? bottom : below;
+ final int maxLineBelow = includePad ? bottom : below;
// similar to the calculation of v below, without the extra.
mMaxLineHeight = v + (maxLineBelow - above);
}
@@ -1049,33 +1067,13 @@
lines[off + mColumns + START] = end;
lines[off + mColumns + TOP] = v;
- // TODO: could move TAB to share same column as HYPHEN, simplifying this code and gaining
- // one bit for start field
- lines[off + TAB] |= flags & TAB_MASK;
- lines[off + HYPHEN] = flags;
-
- lines[off + DIR] |= dir << DIR_SHIFT;
- Directions linedirs = DIRS_ALL_LEFT_TO_RIGHT;
- // easy means all chars < the first RTL, so no emoji, no nothing
- // XXX a run with no text or all spaces is easy but might be an empty
- // RTL paragraph. Make sure easy is false if this is the case.
- if (easy) {
- mLineDirections[j] = linedirs;
- } else {
- mLineDirections[j] = AndroidBidi.directions(dir, chdirs, start - widthStart, chs,
- start - widthStart, end - start);
- }
-
mLineCount++;
return v;
}
- private void calculateEllipsis(int lineStart, int lineEnd,
- float[] widths, int widthStart,
- float avail, TextUtils.TruncateAt where,
- int line, float textWidth, TextPaint paint,
- boolean forceEllipsis) {
- avail -= getTotalInsets(line);
+ private void calculateEllipsis(CharSequence text, int lineStart, int lineEnd, float[] widths,
+ int widthStart, float avail, TextUtils.TruncateAt where, int line, float textWidth,
+ TextPaint paint, boolean forceEllipsis, int dir) {
if (textWidth <= avail && !forceEllipsis) {
// Everything fits!
mLines[mColumns * line + ELLIPSIS_START] = 0;
@@ -1083,11 +1081,53 @@
return;
}
- float ellipsisWidth = paint.measureText(TextUtils.getEllipsisString(where));
- int ellipsisStart = 0;
- int ellipsisCount = 0;
- int len = lineEnd - lineStart;
+ float tempAvail = avail;
+ int numberOfTries = 0;
+ boolean lineFits = false;
+ mWorkPaint.set(paint);
+ do {
+ final float ellipsizedWidth = guessEllipsis(text, lineStart, lineEnd, widths,
+ widthStart, tempAvail, where, line, textWidth, mWorkPaint, forceEllipsis, dir);
+ if (ellipsizedWidth <= avail) {
+ lineFits = true;
+ } else {
+ numberOfTries++;
+ if (numberOfTries > 10) {
+ // If the text still doesn't fit after ten tries, assume it will never fit and
+ // ellipsize it all.
+ mLines[mColumns * line + ELLIPSIS_START] = 0;
+ mLines[mColumns * line + ELLIPSIS_COUNT] = lineEnd - lineStart;
+ lineFits = true;
+ } else {
+ // Some side effect of ellipsization has caused the text to go over the
+ // available width. Let's make the available width shorter by exactly that
+ // amount and retry.
+ tempAvail -= ellipsizedWidth - avail;
+ }
+ }
+ } while (!lineFits);
+ mEllipsized = true;
+ }
+ // Returns the width of the ellipsized line which in some rare cases can actually be larger
+ // than 'avail' (due to kerning or other context-based effect of replacement of text by
+ // ellipsis). If all the line needs to ellipsized away, or it's an invalud hyphenation mode,
+ // returns 0 so the caller can stop iterating.
+ //
+ // This method temporarily modifies the TextPaint passed to it, so the TextPaint passed to it
+ // should not be accessed while the method is running.
+ private float guessEllipsis(CharSequence text, int lineStart, int lineEnd, float[] widths,
+ int widthStart, float avail, TextUtils.TruncateAt where, int line, float textWidth,
+ TextPaint paint, boolean forceEllipsis, int dir) {
+ final int savedHyphenEdit = paint.getHyphenEdit();
+ paint.setHyphenEdit(0);
+ final float ellipsisWidth = paint.measureText(TextUtils.getEllipsisString(where));
+ final int ellipsisStart;
+ final int ellipsisCount;
+ final int len = lineEnd - lineStart;
+ final int offset = lineStart - widthStart;
+
+ int hyphen = getHyphen(line);
// We only support start ellipsis on a single line
if (where == TextUtils.TruncateAt.START) {
if (mMaximumVisibleLineCount == 1) {
@@ -1095,9 +1135,9 @@
int i;
for (i = len; i > 0; i--) {
- float w = widths[i - 1 + lineStart - widthStart];
+ final float w = widths[i - 1 + offset];
if (w + sum + ellipsisWidth > avail) {
- while (i < len && widths[i + lineStart - widthStart] == 0.0f) {
+ while (i < len && widths[i + offset] == 0.0f) {
i++;
}
break;
@@ -1108,9 +1148,13 @@
ellipsisStart = 0;
ellipsisCount = i;
+ // Strip the potential hyphenation at beginning of line.
+ hyphen &= ~Paint.HYPHENEDIT_MASK_START_OF_LINE;
} else {
+ ellipsisStart = 0;
+ ellipsisCount = 0;
if (Log.isLoggable(TAG, Log.WARN)) {
- Log.w(TAG, "Start Ellipsis only supported with one line");
+ Log.w(TAG, "Start ellipsis only supported with one line");
}
}
} else if (where == TextUtils.TruncateAt.END || where == TextUtils.TruncateAt.MARQUEE ||
@@ -1119,7 +1163,7 @@
int i;
for (i = 0; i < len; i++) {
- float w = widths[i + lineStart - widthStart];
+ final float w = widths[i + offset];
if (w + sum + ellipsisWidth > avail) {
break;
@@ -1128,24 +1172,27 @@
sum += w;
}
- ellipsisStart = i;
- ellipsisCount = len - i;
- if (forceEllipsis && ellipsisCount == 0 && len > 0) {
+ if (forceEllipsis && i == len && len > 0) {
ellipsisStart = len - 1;
ellipsisCount = 1;
+ } else {
+ ellipsisStart = i;
+ ellipsisCount = len - i;
}
- } else {
- // where = TextUtils.TruncateAt.MIDDLE We only support middle ellipsis on a single line
+ // Strip the potential hyphenation at end of line.
+ hyphen &= ~Paint.HYPHENEDIT_MASK_END_OF_LINE;
+ } else { // where = TextUtils.TruncateAt.MIDDLE
+ // We only support middle ellipsis on a single line.
if (mMaximumVisibleLineCount == 1) {
float lsum = 0, rsum = 0;
int left = 0, right = len;
- float ravail = (avail - ellipsisWidth) / 2;
+ final float ravail = (avail - ellipsisWidth) / 2;
for (right = len; right > 0; right--) {
- float w = widths[right - 1 + lineStart - widthStart];
+ final float w = widths[right - 1 + offset];
if (w + rsum > ravail) {
- while (right < len && widths[right + lineStart - widthStart] == 0.0f) {
+ while (right < len && widths[right + offset] == 0.0f) {
right++;
}
break;
@@ -1153,9 +1200,9 @@
rsum += w;
}
- float lavail = avail - ellipsisWidth - rsum;
+ final float lavail = avail - ellipsisWidth - rsum;
for (left = 0; left < right; left++) {
- float w = widths[left + lineStart - widthStart];
+ final float w = widths[left + offset];
if (w + lsum > lavail) {
break;
@@ -1167,14 +1214,53 @@
ellipsisStart = left;
ellipsisCount = right - left;
} else {
+ ellipsisStart = 0;
+ ellipsisCount = 0;
if (Log.isLoggable(TAG, Log.WARN)) {
- Log.w(TAG, "Middle Ellipsis only supported with one line");
+ Log.w(TAG, "Middle ellipsis only supported with one line");
}
}
}
- mEllipsized = true;
mLines[mColumns * line + ELLIPSIS_START] = ellipsisStart;
mLines[mColumns * line + ELLIPSIS_COUNT] = ellipsisCount;
+
+ if (ellipsisStart == 0 && (ellipsisCount == 0 || ellipsisCount == len)) {
+ // Unsupported ellipsization mode or all text is ellipsized away. Return 0.
+ return 0.0f;
+ }
+
+ final boolean isSpanned = text instanceof Spanned;
+ final Ellipsizer ellipsizedText = isSpanned
+ ? new SpannedEllipsizer(text)
+ : new Ellipsizer(text);
+ ellipsizedText.mLayout = this;
+ ellipsizedText.mMethod = where;
+
+ final boolean hasTabs = getLineContainsTab(line);
+ final TabStops tabStops;
+ if (hasTabs && isSpanned) {
+ final TabStopSpan[] tabs = getParagraphSpans((Spanned) ellipsizedText, lineStart,
+ lineEnd, TabStopSpan.class);
+ if (tabs.length == 0) {
+ tabStops = null;
+ } else {
+ tabStops = new TabStops(TAB_INCREMENT, tabs);
+ }
+ } else {
+ tabStops = null;
+ }
+ paint.setHyphenEdit(hyphen);
+ final TextLine textline = TextLine.obtain();
+ textline.set(paint, ellipsizedText, lineStart, lineEnd, dir, getLineDirections(line),
+ hasTabs, tabStops);
+ // Since TextLine.metric() returns negative values for RTL text, multiplication by dir
+ // converts it to an actual width. Note that we don't want to use the absolute value,
+ // since we may actually have glyphs with negative advances, which by definition always
+ // fit.
+ final float ellipsizedWidth = textline.metrics(null) * dir;
+ TextLine.recycle(textline);
+ paint.setHyphenEdit(savedHyphenEdit);
+ return ellipsizedWidth;
}
private float getTotalInsets(int line) {
@@ -1407,6 +1493,8 @@
*/
private int mMaxLineHeight = DEFAULT_MAX_LINE_HEIGHT;
+ private TextPaint mWorkPaint = new TextPaint();
+
private static final int COLUMNS_NORMAL = 5;
private static final int COLUMNS_ELLIPSIZE = 7;
private static final int START = 0;