Merge "Improve mailbox sync and load more." into jb-ub-mail-ur9

emailcommon/src/com/android/emailcommon/provider/EmailContent.java

@@ -1609,10 +1609,12 @@ public abstract class EmailContent {
         // Other states, as a bit field, e.g. CHILDREN_VISIBLE, HAS_CHILDREN
         public static final String FLAGS = "flags";
         // Backward compatible
+        @Deprecated
         public static final String VISIBLE_LIMIT = "visibleLimit";
         // Sync status (can be used as desired by sync services)
         public static final String SYNC_STATUS = "syncStatus";
         // Number of messages in the mailbox.
+        @Deprecated
         public static final String MESSAGE_COUNT = "messageCount";
         // The last time a message in this mailbox has been read (in millis)
         public static final String LAST_TOUCHED_TIME = "lastTouchedTime";

emailcommon/src/com/android/emailcommon/provider/Mailbox.java

@@ -29,17 +29,18 @@ import android.util.Log;
 import com.android.emailcommon.Logging;
 import com.android.emailcommon.R;
 import com.android.emailcommon.provider.EmailContent.MailboxColumns;
-import com.android.emailcommon.provider.EmailContent.SyncColumns;
 import com.android.emailcommon.utility.Utility;
 
-public class Mailbox extends EmailContent implements SyncColumns, MailboxColumns, Parcelable {
+public class Mailbox extends EmailContent implements MailboxColumns, Parcelable {
     public static final String TABLE_NAME = "Mailbox";
 
     public static Uri CONTENT_URI;
+    public static Uri MESSAGE_COUNT_URI;
     public static Uri FROM_ACCOUNT_AND_TYPE_URI;
 
     public static void initMailbox() {
         CONTENT_URI = Uri.parse(EmailContent.CONTENT_URI + "/mailbox");
+        MESSAGE_COUNT_URI = Uri.parse(EmailContent.CONTENT_URI + "/mailboxCount");
         FROM_ACCOUNT_AND_TYPE_URI = Uri.parse(EmailContent.CONTENT_URI +
                 "/mailboxIdFromAccountAndType");
     }
@@ -57,7 +58,6 @@ public class Mailbox extends EmailContent implements SyncColumns, MailboxColumns
     public long mSyncTime;
     public boolean mFlagVisible = true;
     public int mFlags;
-    public int mVisibleLimit;
     public String mSyncStatus;
     public long mLastTouchedTime;
     public int mUiSyncStatus;
@@ -78,14 +78,13 @@ public class Mailbox extends EmailContent implements SyncColumns, MailboxColumns
     public static final int CONTENT_SYNC_TIME_COLUMN = 10;
     public static final int CONTENT_FLAG_VISIBLE_COLUMN = 11;
     public static final int CONTENT_FLAGS_COLUMN = 12;
-    public static final int CONTENT_VISIBLE_LIMIT_COLUMN = 13;
+    public static final int CONTENT_SYNC_STATUS_COLUMN = 13;
-    public static final int CONTENT_SYNC_STATUS_COLUMN = 14;
+    public static final int CONTENT_PARENT_KEY_COLUMN = 14;
-    public static final int CONTENT_PARENT_KEY_COLUMN = 15;
+    public static final int CONTENT_LAST_TOUCHED_TIME_COLUMN = 15;
-    public static final int CONTENT_LAST_TOUCHED_TIME_COLUMN = 16;
+    public static final int CONTENT_UI_SYNC_STATUS_COLUMN = 16;
-    public static final int CONTENT_UI_SYNC_STATUS_COLUMN = 17;
+    public static final int CONTENT_UI_LAST_SYNC_RESULT_COLUMN = 17;
-    public static final int CONTENT_UI_LAST_SYNC_RESULT_COLUMN = 18;
+    public static final int CONTENT_TOTAL_COUNT_COLUMN = 18;
-    public static final int CONTENT_TOTAL_COUNT_COLUMN = 19;
+    public static final int CONTENT_HIERARCHICAL_NAME_COLUMN = 19;
-    public static final int CONTENT_HIERARCHICAL_NAME_COLUMN = 20;
 
     /**
      * <em>NOTE</em>: If fields are added or removed, the method {@link #getHashes()}
@@ -95,31 +94,17 @@ public class Mailbox extends EmailContent implements SyncColumns, MailboxColumns
         RECORD_ID, MailboxColumns.DISPLAY_NAME, MailboxColumns.SERVER_ID,
         MailboxColumns.PARENT_SERVER_ID, MailboxColumns.ACCOUNT_KEY, MailboxColumns.TYPE,
         MailboxColumns.DELIMITER, MailboxColumns.SYNC_KEY, MailboxColumns.SYNC_LOOKBACK,
-        MailboxColumns.SYNC_INTERVAL, MailboxColumns.SYNC_TIME,
+        MailboxColumns.SYNC_INTERVAL, MailboxColumns.SYNC_TIME, MailboxColumns.FLAG_VISIBLE,
-        MailboxColumns.FLAG_VISIBLE, MailboxColumns.FLAGS, MailboxColumns.VISIBLE_LIMIT,
+        MailboxColumns.FLAGS, MailboxColumns.SYNC_STATUS, MailboxColumns.PARENT_KEY,
-        MailboxColumns.SYNC_STATUS, MailboxColumns.PARENT_KEY, MailboxColumns.LAST_TOUCHED_TIME,
+        MailboxColumns.LAST_TOUCHED_TIME, MailboxColumns.UI_SYNC_STATUS,
-        MailboxColumns.UI_SYNC_STATUS, MailboxColumns.UI_LAST_SYNC_RESULT,
+        MailboxColumns.UI_LAST_SYNC_RESULT, MailboxColumns.TOTAL_COUNT,
-        MailboxColumns.TOTAL_COUNT, MailboxColumns.HIERARCHICAL_NAME
+        MailboxColumns.HIERARCHICAL_NAME
     };
 
-    private static final String ACCOUNT_AND_MAILBOX_TYPE_SELECTION =
-            MailboxColumns.ACCOUNT_KEY + " =? AND " +
-            MailboxColumns.TYPE + " =?";
-    private static final String MAILBOX_TYPE_SELECTION =
-            MailboxColumns.TYPE + " =?";
     /** Selection by server pathname for a given account */
     public static final String PATH_AND_ACCOUNT_SELECTION =
         MailboxColumns.SERVER_ID + "=? and " + MailboxColumns.ACCOUNT_KEY + "=?";
 
-    private static final String[] MAILBOX_SUM_OF_UNREAD_COUNT_PROJECTION = new String [] {
-            "sum(" + MailboxColumns.UNREAD_COUNT + ")"
-            };
-    private static final int UNREAD_COUNT_COUNT_COLUMN = 0;
-    private static final String[] MAILBOX_SUM_OF_MESSAGE_COUNT_PROJECTION = new String [] {
-            "sum(" + MailboxColumns.MESSAGE_COUNT + ")"
-            };
-    private static final int MESSAGE_COUNT_COUNT_COLUMN = 0;
-
     private static final String[] MAILBOX_TYPE_PROJECTION = new String [] {
             MailboxColumns.TYPE
             };
@@ -228,6 +213,11 @@ public class Mailbox extends EmailContent implements SyncColumns, MailboxColumns
     public static final long QUERY_ALL_DRAFTS = -5;
     public static final long QUERY_ALL_OUTBOX = -6;
 
+    /**
+     * Specifies how many messages will be shown in a folder when it is first synced.
+     */
+    public static final int FIRST_SYNC_MESSAGE_COUNT = 25;
+
     public Mailbox() {
         mBaseUri = CONTENT_URI;
     }
@@ -380,7 +370,6 @@ public class Mailbox extends EmailContent implements SyncColumns, MailboxColumns
         mSyncTime = cursor.getLong(CONTENT_SYNC_TIME_COLUMN);
         mFlagVisible = cursor.getInt(CONTENT_FLAG_VISIBLE_COLUMN) == 1;
         mFlags = cursor.getInt(CONTENT_FLAGS_COLUMN);
-        mVisibleLimit = cursor.getInt(CONTENT_VISIBLE_LIMIT_COLUMN);
         mSyncStatus = cursor.getString(CONTENT_SYNC_STATUS_COLUMN);
         mLastTouchedTime = cursor.getLong(CONTENT_LAST_TOUCHED_TIME_COLUMN);
         mUiSyncStatus = cursor.getInt(CONTENT_UI_SYNC_STATUS_COLUMN);
@@ -405,7 +394,6 @@ public class Mailbox extends EmailContent implements SyncColumns, MailboxColumns
         values.put(MailboxColumns.SYNC_TIME, mSyncTime);
         values.put(MailboxColumns.FLAG_VISIBLE, mFlagVisible);
         values.put(MailboxColumns.FLAGS, mFlags);
-        values.put(MailboxColumns.VISIBLE_LIMIT, mVisibleLimit);
         values.put(MailboxColumns.SYNC_STATUS, mSyncStatus);
         values.put(MailboxColumns.LAST_TOUCHED_TIME, mLastTouchedTime);
         values.put(MailboxColumns.UI_SYNC_STATUS, mUiSyncStatus);
@@ -415,6 +403,44 @@ public class Mailbox extends EmailContent implements SyncColumns, MailboxColumns
         return values;
     }
 
+    /**
+     * During sync, updates the remote message count, and determine how many messages to sync down
+     * for this mailbox.
+     * @param c
+     * @param remoteMessageCount the current message count on the server; this might be different
+     * from this object's current message count (in which case it will be written back to the db).
+     * @param deltaMessageCount the minimum number of additional messages to sync for this request.
+     * @return
+     */
+    public int handleCountsForSync(Context c, final int remoteMessageCount,
+            final int deltaMessageCount) {
+        // Write the remote message count to the DB if necessary.
+        if (remoteMessageCount != mTotalCount) {
+            ContentValues values = new ContentValues();
+            values.put(MailboxColumns.TOTAL_COUNT, remoteMessageCount);
+            update(c, values);
+        }
+
+        // TODO: The value computed below is not quite right if the messages we have are not
+        // actually a subset of the server side messages, but it's close enough?
+
+        final int currentMessageCount = getMailboxMessageCount(c, mId);
+
+        // Determine how many "new" messages we have. If we've never synced before, then use a
+        // default value, otherwise it's the actual change in remote count.
+        final int newMessageCount;
+        if (mSyncTime == 0) {
+            newMessageCount = FIRST_SYNC_MESSAGE_COUNT;
+        } else {
+            newMessageCount = Math.max(0, remoteMessageCount - mTotalCount);
+        }
+
+        // Determine the desired number of messages to sync.
+        final int messageCount = currentMessageCount + Math.max(newMessageCount, deltaMessageCount);
+        // Limit to [0, remoteMessageCount].
+        return Math.min(Math.max(0, messageCount), remoteMessageCount);
+    }
+
     /**
      * Convenience method to return the id of a given type of Mailbox for a given Account; the
      * common Mailbox types (Inbox, Outbox, Sent, Drafts, Trash, and Search) are all cached by
@@ -461,29 +487,6 @@ public class Mailbox extends EmailContent implements SyncColumns, MailboxColumns
         return null;
     }
 
-    public static int getUnreadCountByAccountAndMailboxType(Context context, long accountId,
-            int type) {
-        return Utility.getFirstRowInt(context, Mailbox.CONTENT_URI,
-                MAILBOX_SUM_OF_UNREAD_COUNT_PROJECTION,
-                ACCOUNT_AND_MAILBOX_TYPE_SELECTION,
-                new String[] { String.valueOf(accountId), String.valueOf(type) },
-                null, UNREAD_COUNT_COUNT_COLUMN, 0);
-    }
-
-    public static int getUnreadCountByMailboxType(Context context, int type) {
-        return Utility.getFirstRowInt(context, Mailbox.CONTENT_URI,
-                MAILBOX_SUM_OF_UNREAD_COUNT_PROJECTION,
-                MAILBOX_TYPE_SELECTION,
-                new String[] { String.valueOf(type) }, null, UNREAD_COUNT_COUNT_COLUMN, 0);
-    }
-
-    public static int getMessageCountByMailboxType(Context context, int type) {
-        return Utility.getFirstRowInt(context, Mailbox.CONTENT_URI,
-                MAILBOX_SUM_OF_MESSAGE_COUNT_PROJECTION,
-                MAILBOX_TYPE_SELECTION,
-                new String[] { String.valueOf(type) }, null, MESSAGE_COUNT_COUNT_COLUMN, 0);
-    }
-
     /**
      * Return the mailbox for a message with a given id
      * @param context the caller's context
@@ -517,6 +520,21 @@ public class Mailbox extends EmailContent implements SyncColumns, MailboxColumns
                 null, null, null, MAILBOX_DISPLAY_NAME_COLUMN);
     }
 
+    public static int getMailboxMessageCount(Context c, long mailboxId) {
+        Cursor cursor = c.getContentResolver().query(
+                ContentUris.withAppendedId(MESSAGE_COUNT_URI, mailboxId), null, null, null, null);
+        if (cursor != null) {
+            try {
+                if (cursor.moveToFirst()) {
+                    return cursor.getInt(0);
+                }
+            } finally {
+                cursor.close();
+            }
+        }
+        return 0;
+    }
+
     /**
      * @param mailboxId ID of a mailbox.  This method accepts magic mailbox IDs, such as
      * {@link #QUERY_ALL_INBOXES}. (They're all non-refreshable.)
@@ -589,8 +607,6 @@ public class Mailbox extends EmailContent implements SyncColumns, MailboxColumns
                 = mFlagVisible;
         hash[CONTENT_FLAGS_COLUMN]
                 = mFlags;
-        hash[CONTENT_VISIBLE_LIMIT_COLUMN]
-                = mVisibleLimit;
         hash[CONTENT_SYNC_STATUS_COLUMN]
                 = mSyncStatus;
         hash[CONTENT_PARENT_KEY_COLUMN]
@@ -632,7 +648,6 @@ public class Mailbox extends EmailContent implements SyncColumns, MailboxColumns
         dest.writeLong(mSyncTime);
         dest.writeInt(mFlagVisible ? 1 : 0);
         dest.writeInt(mFlags);
-        dest.writeInt(mVisibleLimit);
         dest.writeString(mSyncStatus);
         dest.writeLong(mLastTouchedTime);
         dest.writeInt(mUiSyncStatus);
@@ -657,7 +672,6 @@ public class Mailbox extends EmailContent implements SyncColumns, MailboxColumns
         mSyncTime = in.readLong();
         mFlagVisible = in.readInt() == 1;
         mFlags = in.readInt();
-        mVisibleLimit = in.readInt();
         mSyncStatus = in.readString();
         mLastTouchedTime = in.readLong();
         mUiSyncStatus = in.readInt();

emailcommon/src/com/android/emailcommon/service/EmailServiceProxy.java

@@ -157,14 +157,16 @@ public class EmailServiceProxy extends ServiceProxy implements IEmailService {
      *
      * @param mailboxId the id of the mailbox record
      * @param userRequest whether or not the user specifically asked for the sync
+     * @param deltaMessageCount amount by which to change the number of messages synced.
      */
     @Override
-    public void startSync(final long mailboxId, final boolean userRequest) throws RemoteException {
+    public void startSync(final long mailboxId, final boolean userRequest,
+            final int deltaMessageCount) throws RemoteException {
         setTask(new ProxyTask() {
             @Override
             public void run() throws RemoteException {
                 if (mCallback != null) mService.setCallback(mCallback);
-                mService.startSync(mailboxId, userRequest);
+                mService.startSync(mailboxId, userRequest, deltaMessageCount);
             }
         }, "startSync");
     }

emailcommon/src/com/android/emailcommon/service/IEmailService.aidl

@@ -26,9 +26,10 @@ import android.os.Bundle;
 interface IEmailService {
     Bundle validate(in HostAuth hostauth);
 
-    oneway void startSync(long mailboxId, boolean userRequest);
+    oneway void startSync(long mailboxId, boolean userRequest, int deltaMessageCount);
     oneway void stopSync(long mailboxId);
 
+    // TODO: loadMore appears to be unused; if so, delete it.
     oneway void loadMore(long messageId);
     oneway void loadAttachment(long attachmentId, boolean background);
 

src/com/android/email/mail/Store.java

@@ -198,6 +198,5 @@ public abstract class Store {
         //mailbox.mSyncTime;
         mailbox.mType = type;
         //box.mUnreadCount;
-        mailbox.mVisibleLimit = MailActivityEmail.VISIBLE_LIMIT_DEFAULT;
     }
 }

src/com/android/email/mail/store/Pop3Store.java

@@ -110,8 +110,6 @@ public class Pop3Store extends Store {
         if (mailbox == null) {
             mailbox = Mailbox.newSystemMailbox(mContext, mAccount.mId, Mailbox.TYPE_INBOX);
         }
-        // TODO: Mailbox.newSystemMailbox should be aware of these default values for inbox?
-        mailbox.mVisibleLimit = MailActivityEmail.VISIBLE_LIMIT_DEFAULT;
         if (mailbox.isSaved()) {
             mailbox.update(mContext, mailbox.toContentValues());
         } else {

src/com/android/email/provider/EmailProvider.java

@@ -192,6 +192,7 @@ public class EmailProvider extends ContentProvider {
     private static final int MAILBOX_ID_FROM_ACCOUNT_AND_TYPE = MAILBOX_BASE + 2;
     private static final int MAILBOX_NOTIFICATION = MAILBOX_BASE + 3;
     private static final int MAILBOX_MOST_RECENT_MESSAGE = MAILBOX_BASE + 4;
+    private static final int MAILBOX_MESSAGE_COUNT = MAILBOX_BASE + 5;
 
     private static final int MESSAGE_BASE = 0x2000;
     private static final int MESSAGE = MESSAGE_BASE;
@@ -1086,6 +1087,7 @@ public class EmailProvider extends ContentProvider {
                         MAILBOX_NOTIFICATION);
                 matcher.addURI(EmailContent.AUTHORITY, "mailboxMostRecentMessage/#",
                         MAILBOX_MOST_RECENT_MESSAGE);
+                matcher.addURI(EmailContent.AUTHORITY, "mailboxCount/#", MAILBOX_MESSAGE_COUNT);
 
                 // All messages
                 matcher.addURI(EmailContent.AUTHORITY, "message", MESSAGE);
@@ -1303,7 +1305,7 @@ public class EmailProvider extends ContentProvider {
                     c = uiFolderLoadMore(uri);
                     return c;
                 case UI_FOLDER_REFRESH:
-                    c = uiFolderRefresh(uri);
+                    c = uiFolderRefresh(uri, 0);
                     return c;
                 case MAILBOX_NOTIFICATION:
                     c = notificationQuery(uri);
@@ -1311,6 +1313,9 @@ public class EmailProvider extends ContentProvider {
                 case MAILBOX_MOST_RECENT_MESSAGE:
                     c = mostRecentMessageQuery(uri);
                     return c;
+                case MAILBOX_MESSAGE_COUNT:
+                    c = getMailboxMessageCount(uri);
+                    return c;
                 case ACCOUNT_DEFAULT_ID:
                     // Start with a snapshot of the cache
                     Map<String, Cursor> accountCache = mCacheAccount.getSnapshot();
@@ -2064,7 +2069,14 @@ outer:
         String mailboxId = uri.getLastPathSegment();
         return db.rawQuery("select max(_id) from Message where mailboxKey=?",
                 new String[] {mailboxId});
-   }
+    }
+
+    private Cursor getMailboxMessageCount(Uri uri) {
+        SQLiteDatabase db = getDatabase(getContext());
+        String mailboxId = uri.getLastPathSegment();
+        return db.rawQuery("select count(*) from Message where mailboxKey=?",
+                new String[] {mailboxId});
+    }
 
     /**
      * Support for UnifiedEmail below
@@ -3755,7 +3767,7 @@ outer:
             final EmailServiceProxy service = EmailServiceUtils.getServiceForAccount(context,
                     mServiceCallback, mailbox.mAccountKey);
             try {
-                service.startSync(mailbox.mId, true);
+                service.startSync(mailbox.mId, true, 0);
             } catch (RemoteException e) {
             }
             final long originalMsgId = msg.mSourceKey;
@@ -4342,7 +4354,7 @@ outer:
         }
     };
 
-    private Cursor uiFolderRefresh(Uri uri) {
+    private Cursor uiFolderRefresh(Uri uri, int deltaMessageCount) {
         Context context = getContext();
         String idString = uri.getLastPathSegment();
         long id = Long.parseLong(idString);
@@ -4351,7 +4363,7 @@ outer:
         EmailServiceProxy service = EmailServiceUtils.getServiceForAccount(context,
                 mServiceCallback, mailbox.mAccountKey);
         try {
-            service.startSync(id, true);
+            service.startSync(id, true, deltaMessageCount);
         } catch (RemoteException e) {
         }
         return null;
@@ -4373,21 +4385,7 @@ outer:
             mSearchParams.mOffset += SEARCH_MORE_INCREMENT;
             runSearchQuery(context, mailbox.mAccountKey, id);
         } else {
-            // Compute the new visibleLimit for this mailbox.
+            uiFolderRefresh(uri, VISIBLE_LIMIT_INCREMENT);
-            int newLimit = mailbox.mVisibleLimit + VISIBLE_LIMIT_INCREMENT;
-            if (newLimit > mailbox.mTotalCount) {
-                newLimit = mailbox.mTotalCount;
-            }
-            // Only do something if the limit is changing.
-            if (newLimit != mailbox.mVisibleLimit) {
-                // Save the new limit to the db.
-                ContentValues values = new ContentValues();
-                values.put(MailboxColumns.VISIBLE_LIMIT, newLimit);
-                context.getContentResolver().update(ContentUris.withAppendedId(Mailbox.CONTENT_URI,
-                        id), values, null, null);
-                // And order a refresh
-                uiFolderRefresh(uri);
-            }
         }
         return null;
     }

src/com/android/email/service/EmailServiceStub.java

@@ -79,6 +79,7 @@ public abstract class EmailServiceStub extends IEmailService.Stub implements IEm
     private static final int MAILBOX_COLUMN_TYPE = 2;
 
     public static final String SYNC_EXTRA_MAILBOX_ID = "__mailboxId__";
+    public static final String SYNC_EXTRA_DELTA_MESSAGE_COUNT = "__deltaMessageCount__";
 
     /** System folders that should always exist. */
     private final int[] DEFAULT_FOLDERS = {
@@ -111,7 +112,8 @@ public abstract class EmailServiceStub extends IEmailService.Stub implements IEm
     }
 
     @Override
-    public void startSync(long mailboxId, boolean userRequest) throws RemoteException {
+    public void startSync(long mailboxId, boolean userRequest, int deltaMessageCount)
+            throws RemoteException {
         Mailbox mailbox = Mailbox.restoreMailboxWithId(mContext, mailboxId);
         if (mailbox == null) return;
         Account account = Account.restoreAccountWithId(mContext, mailbox.mAccountKey);
@@ -126,6 +128,9 @@ public abstract class EmailServiceStub extends IEmailService.Stub implements IEm
             extras.putBoolean(ContentResolver.SYNC_EXTRAS_EXPEDITED, true);
         }
         extras.putLong(SYNC_EXTRA_MAILBOX_ID, mailboxId);
+        if (deltaMessageCount != 0) {
+            extras.putInt(SYNC_EXTRA_DELTA_MESSAGE_COUNT, deltaMessageCount);
+        }
         ContentResolver.requestSync(acct, EmailContent.AUTHORITY, extras);
     }
 
@@ -420,7 +425,7 @@ public abstract class EmailServiceStub extends IEmailService.Stub implements IEm
             }
             // If we just created the inbox, sync it
             if (inboxId != -1) {
-                startSync(inboxId, true);
+                startSync(inboxId, true, 0);
             }
         }
     }

src/com/android/email/service/EmailServiceUtils.java

@@ -58,7 +58,6 @@ import com.android.emailcommon.service.IEmailServiceCallback;
 import com.android.emailcommon.service.SearchParams;
 import com.android.emailcommon.service.SyncWindow;
 
-import com.android.mail.utils.LogUtils;
 import com.google.common.collect.Lists;
 import com.google.common.collect.Maps;
 import org.xmlpull.v1.XmlPullParserException;
@@ -597,7 +596,8 @@ public class EmailServiceUtils {
         }
 
         @Override
-        public void startSync(long mailboxId, boolean userRequest) throws RemoteException {
+        public void startSync(long mailboxId, boolean userRequest, int deltaMessageCount)
+                throws RemoteException {
         }
 
         @Override

src/com/android/email/service/ImapService.java

@@ -165,10 +165,11 @@ public class ImapService extends Service {
      * TODO this should use ID's instead of fully-restored objects
      * @param account
      * @param folder
+     * @param deltaMessageCount requested change in number of messages to sync
      * @throws MessagingException
      */
     public static void synchronizeMailboxSynchronous(Context context, final Account account,
-            final Mailbox folder) throws MessagingException {
+            final Mailbox folder, final int deltaMessageCount) throws MessagingException {
         sendMailboxStatus(folder, EmailServiceStatus.IN_PROGRESS);
 
         TrafficStats.setThreadStatsTag(TrafficFlags.getSyncFlags(context, account));
@@ -178,7 +179,7 @@ public class ImapService extends Service {
         NotificationController nc = NotificationController.getInstance(context);
         try {
             processPendingActionsSynchronous(context, account);
-            synchronizeMailboxGeneric(context, account, folder);
+            synchronizeMailboxGeneric(context, account, folder, deltaMessageCount);
             // Clear authentication notification for this account
             nc.cancelLoginFailedNotification(account.mId);
             sendMailboxStatus(folder, EmailServiceStatus.SUCCESS);
@@ -335,12 +336,12 @@ public class ImapService extends Service {
      *
      * @param account the account to sync
      * @param mailbox the mailbox to sync
+     * @param deltaMessageCount requested change in number of messages to sync
      * @return results of the sync pass
      * @throws MessagingException
      */
-    private static void synchronizeMailboxGeneric(final Context context,
+    private static void synchronizeMailboxGeneric(final Context context, final Account account,
-            final Account account, final Mailbox mailbox) throws MessagingException {
+            final Mailbox mailbox, final int deltaMessageCount) throws MessagingException {
-
         /*
          * A list of IDs for messages that were downloaded and did not have the seen flag set.
          * This serves as the "true" new message count reported to the user via notification.
@@ -414,25 +415,12 @@ public class ImapService extends Service {
         // 4. Trash any remote messages that are marked as trashed locally.
         // TODO - this comment was here, but no code was here.
 
-        ContentValues values = new ContentValues();
+        // 5. Get the number of messages on the server.
+        final int remoteMessageCount = remoteFolder.getMessageCount();
 
-        // 5. Get the remote message count.
+        // 6. Update the total count and determine new message count to sync.
-        int remoteMessageCount = remoteFolder.getMessageCount();
+        final int messageCount = mailbox.handleCountsForSync(context, remoteMessageCount,
-        values.put(MailboxColumns.TOTAL_COUNT, remoteMessageCount);
+                deltaMessageCount);
-
-        // 6. Determine the limit # of messages to download
-        int visibleLimit = mailbox.mVisibleLimit;
-        if (visibleLimit <= 0) {
-            visibleLimit = MailActivityEmail.VISIBLE_LIMIT_DEFAULT;
-        }
-        if (visibleLimit > remoteMessageCount) {
-            visibleLimit = remoteMessageCount;
-        }
-        if (visibleLimit != mailbox.mVisibleLimit) {
-            values.put(MailboxColumns.VISIBLE_LIMIT, visibleLimit);
-        }
-
-        mailbox.update(context, values);
 
         // 7.  Create a list of messages to download
         Message[] remoteMessages = new Message[0];
@@ -443,7 +431,7 @@ public class ImapService extends Service {
             /*
              * Message numbers start at 1.
              */
-            int remoteStart = Math.max(0, remoteMessageCount - visibleLimit) + 1;
+            int remoteStart = Math.max(0, remoteMessageCount - messageCount) + 1;
             int remoteEnd = remoteMessageCount;
             remoteMessages = remoteFolder.getMessages(remoteStart, remoteEnd, null);
             // TODO Why are we running through the list twice? Combine w/ for loop below
@@ -616,7 +604,7 @@ public class ImapService extends Service {
                     protocolSearchInfo.equals(mLastSearchServerId)) {
                 return mLastSearchRemoteMailbox;
             }
-            Cursor c =  context.getContentResolver().query(Mailbox.CONTENT_URI,
+            Cursor c = context.getContentResolver().query(Mailbox.CONTENT_URI,
                     Mailbox.CONTENT_PROJECTION, Mailbox.PATH_AND_ACCOUNT_SELECTION,
                     new String[] {protocolSearchInfo, Long.toString(accountKey)},
                     null);

src/com/android/email/service/Pop3Service.java

@@ -103,7 +103,7 @@ public class Pop3Service extends Service {
             long inboxId = Mailbox.findMailboxOfType(mContext, att.mAccountKey, Mailbox.TYPE_INBOX);
             if (inboxId == Mailbox.NO_MAILBOX) return;
             // We load attachments during a sync
-            startSync(inboxId, true);
+            startSync(inboxId, true, 0);
         }
 
         @Override
@@ -129,10 +129,11 @@ public class Pop3Service extends Service {
      *
      * @param account
      * @param folder
+     * @param deltaMessageCount the requested change in number of messages to sync.
      * @throws MessagingException
      */
     public static void synchronizeMailboxSynchronous(Context context, final Account account,
-            final Mailbox folder) throws MessagingException {
+            final Mailbox folder, final int deltaMessageCount) throws MessagingException {
         sendMailboxStatus(folder, EmailServiceStatus.IN_PROGRESS);
 
         TrafficStats.setThreadStatsTag(TrafficFlags.getSyncFlags(context, account));
@@ -141,7 +142,7 @@ public class Pop3Service extends Service {
         }
         NotificationController nc = NotificationController.getInstance(context);
         try {
-            synchronizePop3Mailbox(context, account, folder);
+            synchronizePop3Mailbox(context, account, folder, deltaMessageCount);
             // Clear authentication notification for this account
             nc.cancelLoginFailedNotification(account.mId);
             sendMailboxStatus(folder, EmailServiceStatus.SUCCESS);
@@ -243,10 +244,11 @@ public class Pop3Service extends Service {
      *
      * @param account the account to sync
      * @param mailbox the mailbox to sync
+     * @param deltaMessageCount the requested change to number of messages to sync
      * @throws MessagingException
      */
-    private static void synchronizePop3Mailbox(final Context context,
+    private static void synchronizePop3Mailbox(final Context context, final Account account,
-            final Account account, final Mailbox mailbox) throws MessagingException {
+            final Mailbox mailbox, final int deltaMessageCount) throws MessagingException {
         // TODO Break this into smaller pieces
         ContentResolver resolver = context.getContentResolver();
 
@@ -293,12 +295,6 @@ public class Pop3Service extends Service {
         // count.
         remoteFolder.open(OpenMode.READ_WRITE);
 
-        // Get the remote message count.
-        int remoteMessageCount = remoteFolder.getMessageCount();
-        ContentValues values = new ContentValues();
-        values.put(MailboxColumns.TOTAL_COUNT, remoteMessageCount);
-        mailbox.update(context, values);
-
         String[] accountIdArgs = new String[] { Long.toString(account.mId) };
         long trashMailboxId = Mailbox.findMailboxOfType(context, account.mId, Mailbox.TYPE_TRASH);
         Cursor updates = resolver.query(
@@ -328,11 +324,12 @@ public class Pop3Service extends Service {
             updates.close();
         }
 
-        // Determine the limit # of messages to download
+        // Get the remote message count.
-        int visibleLimit = mailbox.mVisibleLimit;
+        final int remoteMessageCount = remoteFolder.getMessageCount();
-        if (visibleLimit <= 0) {
+
-            visibleLimit = MailActivityEmail.VISIBLE_LIMIT_DEFAULT;
+        // Update the total count and determine new message count to sync.
-        }
+        final int messageCount = mailbox.handleCountsForSync(context, remoteMessageCount,
+                deltaMessageCount);
 
         // Create a list of messages to download
         Pop3Message[] remoteMessages = new Pop3Message[0];
@@ -343,7 +340,7 @@ public class Pop3Service extends Service {
             /*
              * Message numbers start at 1.
              */
-            remoteMessages = remoteFolder.getMessages(remoteMessageCount, visibleLimit);
+            remoteMessages = remoteFolder.getMessages(remoteMessageCount, messageCount);
 
             /*
              * Get a list of the messages that are in the remote list but not on
@@ -378,7 +375,7 @@ public class Pop3Service extends Service {
                         AttachmentColumns.UI_STATE + "=" + AttachmentState.DOWNLOADING,
                 new String[] {Long.toString(account.mId)}, null);
         try {
-            values.clear();
+            final ContentValues values = new ContentValues();
             while (c.moveToNext()) {
                 values.put(AttachmentColumns.UI_STATE, UIProvider.AttachmentState.SAVED);
                 Attachment att = new Attachment();

src/com/android/email/service/PopImapSyncAdapterService.java

@@ -109,7 +109,7 @@ public class PopImapSyncAdapterService extends Service {
     }
 
     private static void sync(Context context, long mailboxId, SyncResult syncResult,
-            boolean uiRefresh) {
+            boolean uiRefresh, int deltaMessageCount) {
         TempDirectory.setTempDirectory(context);
         Mailbox mailbox = Mailbox.restoreMailboxWithId(context, mailboxId);
         if (mailbox == null) return;
@@ -139,9 +139,11 @@ public class PopImapSyncAdapterService extends Service {
                 if (mailbox.mType == Mailbox.TYPE_OUTBOX) {
                     EmailServiceStub.sendMailImpl(context, account.mId);
                 } else if (protocol.equals(legacyImapProtocol)) {
-                    ImapService.synchronizeMailboxSynchronous(context, account, mailbox);
+                    ImapService.synchronizeMailboxSynchronous(context, account, mailbox,
+                            deltaMessageCount);
                 } else {
-                    Pop3Service.synchronizeMailboxSynchronous(context, account, mailbox);
+                    Pop3Service.synchronizeMailboxSynchronous(context, account, mailbox,
+                            deltaMessageCount);
                 }
             } catch (MessagingException e) {
                 int cause = e.getExceptionType();
@@ -155,8 +157,9 @@ public class PopImapSyncAdapterService extends Service {
                 }
             }
         } finally {
-            // Always clear our sync state
+            // Always clear our sync state and update sync time.
             values.put(Mailbox.UI_SYNC_STATUS, EmailContent.SYNC_STATUS_NONE);
+            values.put(Mailbox.SYNC_TIME, System.currentTimeMillis());
             resolver.update(mailboxUri, values, null, null);
         }
     }
@@ -200,7 +203,7 @@ public class PopImapSyncAdapterService extends Service {
                         }
                     }
                     for (long mailboxId: mailboxesToUpdate) {
-                        sync(context, mailboxId, syncResult, false);
+                        sync(context, mailboxId, syncResult, false, 0);
                     }
                 } else {
                     Log.d(TAG, "Sync request for " + acct.mDisplayName);
@@ -222,7 +225,9 @@ public class PopImapSyncAdapterService extends Service {
                     if (mailboxId == Mailbox.NO_MAILBOX) return;
                     boolean uiRefresh =
                             extras.getBoolean(ContentResolver.SYNC_EXTRAS_EXPEDITED, false);
-                    sync(context, mailboxId, syncResult, uiRefresh);
+                    int deltaMessageCount =
+                            extras.getInt(EmailServiceStub.SYNC_EXTRA_DELTA_MESSAGE_COUNT, 0);
+                    sync(context, mailboxId, syncResult, uiRefresh, deltaMessageCount);
 
                     // Outbox is a special case here
                     Mailbox mailbox = Mailbox.restoreMailboxWithId(context, mailboxId);

src/com/android/email2/ui/MailActivityEmail.java

@@ -78,18 +78,6 @@ public class MailActivityEmail extends com.android.mail.ui.MailActivity {
      */
     public static boolean sDebugInhibitGraphicsAcceleration = false;
 
-    /**
-     * Specifies how many messages will be shown in a folder by default. This number is set
-     * on each new folder and can be incremented with "Load more messages..." by the
-     * VISIBLE_LIMIT_INCREMENT
-     */
-    public static final int VISIBLE_LIMIT_DEFAULT = 25;
-
-    /**
-     * Number of additional messages to load when a user selects "Load more messages..."
-     */
-    public static final int VISIBLE_LIMIT_INCREMENT = 25;
-
     /**
      * This is used to force stacked UI to return to the "welcome" screen any time we change
      * the accounts list (e.g. deleting accounts in the Account Manager preferences.)