Use system collator for display names.

Continue sorting directory names first, but use system collator in
case-insensitive ordering.

Bug: 13545569
Change-Id: I24b314c9ef42f397bc96f474d9593bdefc0061d1

2 files changed, 37 insertions, 12 deletions

diff --git a/packages/DocumentsUI/src/com/android/documentsui/SortingCursorWrapper.java b/packages/DocumentsUI/src/com/android/documentsui/SortingCursorWrapper.java
index a23dd15..6c8ca20 100644
--- a/packages/DocumentsUI/src/com/android/documentsui/SortingCursorWrapper.java
+++ b/packages/DocumentsUI/src/com/android/documentsui/SortingCursorWrapper.java
@@ -27,6 +27,8 @@ import android.database.Cursor;
 import android.os.Bundle;
 import android.provider.DocumentsContract.Document;
 
+import com.android.documentsui.model.DocumentInfo;
+
 /**
  * Cursor wrapper that presents a sorted view of the underlying cursor. Handles
  * common {@link Document} sorting modes, such as ordering directories first.
@@ -68,7 +70,7 @@ public class SortingCursorWrapper extends AbstractCursor {
                     final String displayName = getCursorString(
                             cursor, Document.COLUMN_DISPLAY_NAME);
                     if (Document.MIME_TYPE_DIR.equals(mimeType)) {
-                        mValueString[i] = '\001' + displayName;
+                        mValueString[i] = DocumentInfo.DIR_PREFIX + displayName;
                     } else {
                         mValueString[i] = displayName;
                     }
@@ -180,14 +182,7 @@ public class SortingCursorWrapper extends AbstractCursor {
 
                 final String lhs = pivotValue;
                 final String rhs = value[mid];
-                final int compare;
-                if (lhs == null) {
-                    compare = -1;
-                } else if (rhs == null) {
-                    compare = 1;
-                } else {
-                    compare = lhs.compareToIgnoreCase(rhs);
-                }
+                final int compare = DocumentInfo.compareToIgnoreCaseNullable(lhs, rhs);
 
                 if (compare < 0) {
                     right = mid;
diff --git a/packages/DocumentsUI/src/com/android/documentsui/model/DocumentInfo.java b/packages/DocumentsUI/src/com/android/documentsui/model/DocumentInfo.java
index 91d9124..1c5ca86 100644
--- a/packages/DocumentsUI/src/com/android/documentsui/model/DocumentInfo.java
+++ b/packages/DocumentsUI/src/com/android/documentsui/model/DocumentInfo.java
@@ -25,6 +25,7 @@ import android.os.Parcelable;
 import android.provider.DocumentsContract;
 import android.provider.DocumentsContract.Document;
 import android.provider.DocumentsProvider;
+import android.text.TextUtils;
 
 import com.android.documentsui.DocumentsApplication;
 import com.android.documentsui.RootCursorWrapper;
@@ -36,6 +37,7 @@ import java.io.DataOutputStream;
 import java.io.FileNotFoundException;
 import java.io.IOException;
 import java.net.ProtocolException;
+import java.text.Collator;
 
 /**
  * Representation of a {@link Document}.
@@ -44,6 +46,13 @@ public class DocumentInfo implements Durable, Parcelable {
     private static final int VERSION_INIT = 1;
     private static final int VERSION_SPLIT_URI = 2;
 
+    private static final Collator sCollator;
+
+    static {
+        sCollator = Collator.getInstance();
+        sCollator.setStrength(Collator.SECONDARY);
+    }
+
     public String authority;
     public String documentId;
     public String mimeType;
@@ -268,9 +277,30 @@ public class DocumentInfo implements Durable, Parcelable {
         throw fnfe;
     }
 
+    /**
+     * String prefix used to indicate the document is a directory.
+     */
+    public static final char DIR_PREFIX = '\001';
+
+    /**
+     * Compare two strings against each other using system default collator in a
+     * case-insensitive mode. Clusters strings prefixed with {@link #DIR_PREFIX}
+     * before other items.
+     */
     public static int compareToIgnoreCaseNullable(String lhs, String rhs) {
-        if (lhs == null) return -1;
-        if (rhs == null) return 1;
-        return lhs.compareToIgnoreCase(rhs);
+        final boolean leftEmpty = TextUtils.isEmpty(lhs);
+        final boolean rightEmpty = TextUtils.isEmpty(rhs);
+
+        if (leftEmpty && rightEmpty) return 0;
+        if (leftEmpty) return -1;
+        if (rightEmpty) return 1;
+
+        final boolean leftDir = (lhs.charAt(0) == DIR_PREFIX);
+        final boolean rightDir = (rhs.charAt(0) == DIR_PREFIX);
+
+        if (leftDir && !rightDir) return -1;
+        if (rightDir && !leftDir) return 1;
+
+        return sCollator.compare(lhs, rhs);
     }
 }