Add static patternToString() with pattern sizelp5.0

Sometimes we need to generate a pattern string when lock pattern utils
cannot query the actual size of the pattern. Add a method which doesn't
depend on LockPatternUtils and accepts a pattern length parameter to
generate the string.

Change-Id: If73334b7030800bed2eec0cd0934b762b10dcaa3
Signed-off-by: Roman Birg <roman@cyngn.com>

2 files changed, 12 insertions, 2 deletions

diff --git a/core/java/com/android/internal/widget/LockPatternUtils.java b/core/java/com/android/internal/widget/LockPatternUtils.java
index 97b9509cff3b..f1d505eedd21 100644
--- a/core/java/com/android/internal/widget/LockPatternUtils.java
+++ b/core/java/com/android/internal/widget/LockPatternUtils.java
@@ -1084,6 +1084,16 @@ public class LockPatternUtils {
      * @return The pattern in string form.
      */
     public String patternToString(List<LockPatternView.Cell> pattern) {
+        return patternToString(pattern, getLockPatternSize());
+    }
+
+    /**
+     * Serialize a pattern.
+     * @param pattern The pattern.
+     * @param patternGridSize the pattern size
+     * @return The pattern in string form.
+     */
+    public static String patternToString(List<LockPatternView.Cell> pattern, int patternGridSize) {
         if (pattern == null) {
             return "";
         }
@@ -1092,7 +1102,7 @@ public class LockPatternUtils {
         byte[] res = new byte[patternSize];
         for (int i = 0; i < patternSize; i++) {
             LockPatternView.Cell cell = pattern.get(i);
-            res[i] = (byte) (cell.getRow() * getLockPatternSize() + cell.getColumn());
+            res[i] = (byte) (cell.getRow() * patternGridSize + cell.getColumn());
         }
         return new String(res);
     }
diff --git a/core/java/com/android/internal/widget/LockPatternView.java b/core/java/com/android/internal/widget/LockPatternView.java
index 816ad1d4ee52..ebaced689d6a 100644
--- a/core/java/com/android/internal/widget/LockPatternView.java
+++ b/core/java/com/android/internal/widget/LockPatternView.java
@@ -1096,7 +1096,7 @@ public class LockPatternView extends View {
     protected Parcelable onSaveInstanceState() {
         Parcelable superState = super.onSaveInstanceState();
         return new SavedState(superState,
-                mLockPatternUtils.patternToString(mPattern),
+                LockPatternUtils.patternToString(mPattern, mPatternSize),
                 mPatternDisplayMode.ordinal(), mPatternSize,
                 mInputEnabled, mInStealthMode, mEnableHapticFeedback, mVisibleDots, mShowErrorPath);
     }