Merge "Support fallback linespacing in DynamicLayout" (c4c3a0f5) · Commits · e / os / android_frameworks_base

api/current.txt

+1 −0

Original line number	Diff line number	Diff line
		@@ -41414,6 +41414,7 @@ package android.text {
		method public android.text.DynamicLayout.Builder setJustificationMode(int);
		method public android.text.DynamicLayout.Builder setLineSpacing(float, float);
		method public android.text.DynamicLayout.Builder setTextDirection(android.text.TextDirectionHeuristic);
		method public android.text.DynamicLayout.Builder setUseLineSpacingFromFallbacks(boolean);
		}

		public abstract interface Editable implements java.lang.Appendable java.lang.CharSequence android.text.GetChars android.text.Spannable {

api/system-current.txt

+1 −0

Original line number	Diff line number	Diff line
		@@ -45018,6 +45018,7 @@ package android.text {
		method public android.text.DynamicLayout.Builder setJustificationMode(int);
		method public android.text.DynamicLayout.Builder setLineSpacing(float, float);
		method public android.text.DynamicLayout.Builder setTextDirection(android.text.TextDirectionHeuristic);
		method public android.text.DynamicLayout.Builder setUseLineSpacingFromFallbacks(boolean);
		}

		public abstract interface Editable implements java.lang.Appendable java.lang.CharSequence android.text.GetChars android.text.Spannable {

api/test-current.txt

+1 −0

Original line number	Diff line number	Diff line
		@@ -41678,6 +41678,7 @@ package android.text {
		method public android.text.DynamicLayout.Builder setJustificationMode(int);
		method public android.text.DynamicLayout.Builder setLineSpacing(float, float);
		method public android.text.DynamicLayout.Builder setTextDirection(android.text.TextDirectionHeuristic);
		method public android.text.DynamicLayout.Builder setUseLineSpacingFromFallbacks(boolean);
		}

		public abstract interface Editable implements java.lang.Appendable java.lang.CharSequence android.text.GetChars android.text.Spannable {

core/java/android/text/DynamicLayout.java

+28 −3

Original line number	Diff line number	Diff line
		@@ -80,6 +80,7 @@ public class DynamicLayout extends Layout
		b.mSpacingMult = DEFAULT_LINESPACING_MULTIPLIER;
		b.mSpacingAdd = DEFAULT_LINESPACING_ADDITION;
		b.mIncludePad = true;
		b.mFallbackLineSpacing = false;
		b.mEllipsizedWidth = width;
		b.mEllipsize = null;
		b.mBreakStrategy = Layout.BREAK_STRATEGY_SIMPLE;
		@@ -171,6 +172,25 @@ public class DynamicLayout extends Layout
		return this;
		}

		/**
		* Set whether to respect the ascent and descent of the fallback fonts that are used in
		* displaying the text (which is needed to avoid text from consecutive lines running into
		* each other). If set, fallback fonts that end up getting used can increase the ascent
		* and descent of the lines that they are used on.
		*
		* <p>For backward compatibility reasons, the default is {@code false}, but setting this to
		* true is strongly recommended. It is required to be true if text could be in languages
		* like Burmese or Tibetan where text is typically much taller or deeper than Latin text.
		*
		* @param useLineSpacingFromFallbacks whether to expand linespacing based on fallback fonts
		* @return this builder, useful for chaining
		*/
		@NonNull
		public Builder setUseLineSpacingFromFallbacks(boolean useLineSpacingFromFallbacks) {
		mFallbackLineSpacing = useLineSpacingFromFallbacks;
		return this;
		}

		/**
		* Set the width as used for ellipsizing purposes, if it differs from the normal layout
		* width. The default is the {@code width} passed to {@link #obtain}.
		@@ -270,6 +290,7 @@ public class DynamicLayout extends Layout
		private float mSpacingMult;
		private float mSpacingAdd;
		private boolean mIncludePad;
		private boolean mFallbackLineSpacing;
		private int mBreakStrategy;
		private int mHyphenationFrequency;
		private int mJustificationMode;
		@@ -320,7 +341,7 @@ public class DynamicLayout extends Layout
		@IntRange(from = 0) int ellipsizedWidth) {
		this(base, display, paint, width, align, TextDirectionHeuristics.FIRSTSTRONG_LTR,
		spacingmult, spacingadd, includepad,
		StaticLayout.BREAK_STRATEGY_SIMPLE, StaticLayout.HYPHENATION_FREQUENCY_NONE,
		Layout.BREAK_STRATEGY_SIMPLE, Layout.HYPHENATION_FREQUENCY_NONE,
		Layout.JUSTIFICATION_MODE_NONE, ellipsize, ellipsizedWidth);
		}

		@@ -388,6 +409,7 @@ public class DynamicLayout extends Layout

		private void generate(@NonNull Builder b) {
		mBase = b.mBase;
		mFallbackLineSpacing = b.mFallbackLineSpacing;
		if (b.mEllipsize != null) {
		mInts = new PackedIntVector(COLUMNS_ELLIPSIZE);
		mEllipsizedWidth = b.mEllipsizedWidth;
		@@ -573,6 +595,7 @@ public class DynamicLayout extends Layout
		.setWidth(getWidth())
		.setTextDirection(getTextDirectionHeuristic())
		.setLineSpacing(getSpacingAdd(), getSpacingMultiplier())
		.setUseLineSpacingFromFallbacks(mFallbackLineSpacing)
		.setEllipsizedWidth(mEllipsizedWidth)
		.setEllipsize(mEllipsizeAt)
		.setBreakStrategy(mBreakStrategy)
		@@ -1033,11 +1056,12 @@ public class DynamicLayout extends Layout
		private void reflow(CharSequence s, int where, int before, int after) {
		DynamicLayout ml = mLayout.get();

		if (ml != null)
		if (ml != null) {
		ml.reflow(s, where, before, after);
		else if (s instanceof Spannable)
		} else if (s instanceof Spannable) {
		((Spannable) s).removeSpan(this);
		}
		}

		public void beforeTextChanged(CharSequence s, int where, int before, int after) {
		// Intentionally empty
		@@ -1093,6 +1117,7 @@ public class DynamicLayout extends Layout
		private CharSequence mDisplay;
		private ChangeWatcher mWatcher;
		private boolean mIncludePad;
		private boolean mFallbackLineSpacing;
		private boolean mEllipsize;
		private int mEllipsizedWidth;
		private TextUtils.TruncateAt mEllipsizeAt;

core/tests/coretests/src/android/text/DynamicLayoutTest.java

+73 −0

Original line number	Diff line number	Diff line
		@@ -186,4 +186,77 @@ public class DynamicLayoutTest {
		ALIGN_NORMAL, 1.0f /spacingMultiplier/, 0f /spacingAdd/, false /includepad/);
		layout.getLineExtra(100);
		}

		@Test
		public void testFallbackLineSpacing() {
		// All glyphs in the fonts are 1em wide.
		final String[] testFontFiles = {
		// ascent == 1em, descent == 2em, only supports 'a' and space
		"ascent1em-descent2em.ttf",
		// ascent == 3em, descent == 4em, only supports 'b'
		"ascent3em-descent4em.ttf"
		};
		final String xml = "<?xml version='1.0' encoding='UTF-8'?>"
		+ "<familyset>"
		+ " <family name='sans-serif'>"
		+ " <font weight='400' style='normal'>ascent1em-descent2em.ttf</font>"
		+ " </family>"
		+ " <family>"
		+ " <font weight='400' style='normal'>ascent3em-descent4em.ttf</font>"
		+ " </family>"
		+ "</familyset>";

		try (FontFallbackSetup setup =
		new FontFallbackSetup("DynamicLayout", testFontFiles, xml)) {
		final TextPaint paint = setup.getPaintFor("sans-serif");
		final int textSize = 100;
		paint.setTextSize(textSize);
		assertEquals(-textSize, paint.ascent(), 0.0f);
		assertEquals(2 * textSize, paint.descent(), 0.0f);

		final int paraWidth = 5 * textSize;
		final String text = "aaaaa aabaa aaaaa"; // This should result in three lines.

		// Old line spacing. All lines should get their ascent and descents from the first font.
		DynamicLayout layout = DynamicLayout.Builder
		.obtain(text, paint, paraWidth)
		.setIncludePad(false)
		.setUseLineSpacingFromFallbacks(false)
		.build();
		assertEquals(3, layout.getLineCount());
		assertEquals(-textSize, layout.getLineAscent(0));
		assertEquals(2 * textSize, layout.getLineDescent(0));
		assertEquals(-textSize, layout.getLineAscent(1));
		assertEquals(2 * textSize, layout.getLineDescent(1));
		assertEquals(-textSize, layout.getLineAscent(2));
		assertEquals(2 * textSize, layout.getLineDescent(2));

		// New line spacing. The second line has a 'b', so it needs more ascent and descent.
		layout = DynamicLayout.Builder
		.obtain(text, paint, paraWidth)
		.setIncludePad(false)
		.setUseLineSpacingFromFallbacks(true)
		.build();
		assertEquals(3, layout.getLineCount());
		assertEquals(-textSize, layout.getLineAscent(0));
		assertEquals(2 * textSize, layout.getLineDescent(0));
		assertEquals(-3 * textSize, layout.getLineAscent(1));
		assertEquals(4 * textSize, layout.getLineDescent(1));
		assertEquals(-textSize, layout.getLineAscent(2));
		assertEquals(2 * textSize, layout.getLineDescent(2));

		// The default is the old line spacing, for backward compatibility.
		layout = DynamicLayout.Builder
		.obtain(text, paint, paraWidth)
		.setIncludePad(false)
		.build();
		assertEquals(3, layout.getLineCount());
		assertEquals(-textSize, layout.getLineAscent(0));
		assertEquals(2 * textSize, layout.getLineDescent(0));
		assertEquals(-textSize, layout.getLineAscent(1));
		assertEquals(2 * textSize, layout.getLineDescent(1));
		assertEquals(-textSize, layout.getLineAscent(2));
		assertEquals(2 * textSize, layout.getLineDescent(2));
		}
		}
		}