commit 09da71a6dcfe07e0efdc35933322fba16091f555
author Seigo Nonaka <nona@google.com> Mon Nov 28 16:24:14 2016 +0900
committer Seigo Nonaka <nona@google.com> Thu Jan 05 18:14:15 2017 +0900
tree 23e2b4c7de31883d6c156a8678a5605a7dc93eb4
parent ab156196f88bf7adac9cbf2779c049fc414be890

Introduce full justification.

Adds a new get/setJustify API to TextView and StaticLayout.Builder for
justification, and fully justifies text when it's enabled.

This is based on a patch by Raph Levien (raph@google.com).

Bug: 31707212
Test: Manually done and CTS will introduced with
      I0f3bbf39d60a66b71b30e1351f7c741208f05dce passes.
Change-Id: Icbfab2faa11a6a0b52e6f0a77a9c9b5ef6e191da

core/java/android/text/StaticLayout.java

diff --git a/core/java/android/text/StaticLayout.java b/core/java/android/text/StaticLayout.java
index 081be3a..cb5b073 100644
--- a/core/java/android/text/StaticLayout.java
+++ b/core/java/android/text/StaticLayout.java
@@ -94,6 +94,7 @@
             b.mMaxLines = Integer.MAX_VALUE;
             b.mBreakStrategy = Layout.BREAK_STRATEGY_SIMPLE;
             b.mHyphenationFrequency = Layout.HYPHENATION_FREQUENCY_NONE;
+            b.mJustify = false;
 
             b.mMeasuredText = MeasuredText.obtain();
             return b;
@@ -320,6 +321,17 @@
         }
 
         /**
+         * Enables or disables paragraph justification. The default value is disabled (false).
+         *
+         * @param justify true for enabling and false for disabling paragraph justification.
+         * @return this builder, useful for chaining.
+         */
+        public Builder setJustify(boolean justify) {
+            mJustify = justify;
+            return this;
+        }
+
+        /**
          * Measurement and break iteration is done in native code. The protocol for using
          * the native code is as follows.
          *
@@ -404,6 +416,7 @@
         int mHyphenationFrequency;
         int[] mLeftIndents;
         int[] mRightIndents;
+        boolean mJustify;
 
         Paint.FontMetricsInt mFontMetricsInt = new Paint.FontMetricsInt();
 
@@ -557,6 +570,7 @@
 
         mLeftIndents = b.mLeftIndents;
         mRightIndents = b.mRightIndents;
+        setJustify(b.mJustify);
 
         generate(b, b.mIncludePad, b.mIncludePad);
     }
@@ -676,7 +690,8 @@
 
             nSetupParagraph(b.mNativePtr, chs, paraEnd - paraStart,
                     firstWidth, firstWidthLineCount, restWidth,
-                    variableTabStops, TAB_INCREMENT, b.mBreakStrategy, b.mHyphenationFrequency);
+                    variableTabStops, TAB_INCREMENT, b.mBreakStrategy, b.mHyphenationFrequency,
+                    b.mJustify);
             if (mLeftIndents != null || mRightIndents != null) {
                 // TODO(raph) 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
@@ -1284,7 +1299,8 @@
     // Set up paragraph text and settings; done as one big method to minimize jni crossings
     private static native void nSetupParagraph(long nativePtr, char[] text, int length,
             float firstWidth, int firstWidthLineCount, float restWidth,
-            int[] variableTabStops, int defaultTabStop, int breakStrategy, int hyphenationFrequency);
+            int[] variableTabStops, int defaultTabStop, int breakStrategy, int hyphenationFrequency,
+            boolean isJustified);
 
     private static native float nAddStyleRun(long nativePtr, long nativePaint,
             long nativeTypeface, int start, int end, boolean isRtl);