Put back prev/next buttons to non-split message views for now.

Some people prefer them over swiping / volume keys.

They could probably be made optional so they can be hidden.

Also: delete the now unused message_view_fragment.xml and message_view_option.xml.

res/menu/message_list_option.xml

@@ -10,6 +10,22 @@
     MessageList.configureMenu() if you make any changes to this file.
     -->
 
+    <!-- MessageView -->
+    <item
+        android:id="@+id/next_message"
+        android:title="@string/next_action"
+        android:icon="?attr/iconActionNextMessage"
+        android:showAsAction="always"
+    />
+
+    <!-- MessageView -->
+    <item
+        android:id="@+id/previous_message"
+        android:title="@string/previous_action"
+        android:icon="?attr/iconActionPreviousMessage"
+        android:showAsAction="always"
+    />
+
     <!-- MessageList -->
     <item
         android:id="@+id/search"

res/menu/message_view_fragment.xml

@@ -1,68 +0,0 @@
-<?xml version="1.0" encoding="utf-8"?>
-<menu xmlns:android="http://schemas.android.com/apk/res/android">
-    <item
-        android:id="@+id/delete"
-        android:alphabeticShortcut="q"
-        android:title="@string/delete_action"
-        android:icon="?attr/iconActionDelete"
-        android:showAsAction="always"
-    />
-    <item
-        android:id="@+id/single_message_options"
-        android:icon="?attr/iconActionSingleMessageOptions"
-        android:showAsAction="ifRoom"
-        android:title="@string/single_message_options_action">
-        <menu>
-            <item
-                android:id="@+id/reply"
-                android:title="@string/reply_action"/>
-            <item
-                android:id="@+id/reply_all"
-                android:title="@string/reply_all_action"/>
-            <item
-                android:id="@+id/forward"
-                android:title="@string/forward_action"/>
-            <item
-                android:id="@+id/share"
-                android:title="@string/send_alternate_action" />
-        </menu>
-    </item>
-    <item
-        android:id="@+id/archive"
-        android:title="@string/archive_action"
-        android:icon="?attr/iconActionArchive"
-        android:showAsAction="ifRoom"
-    />
-    <item
-        android:id="@+id/spam"
-        android:title="@string/spam_action"
-        android:icon="?attr/iconActionSpam"
-        android:showAsAction="ifRoom"
-    />
-    <item
-        android:id="@+id/move"
-            android:showAsAction="ifRoom"
-                android:icon="?attr/iconActionMoveOrCopy"
-        android:title="@string/move_action"
-    />
-    <item
-        android:id="@+id/copy"
-        android:title="@string/copy_action"
-    />
-    <item
-        android:id="@+id/toggle_unread"
-        android:alphabeticShortcut="u"
-        android:title="@string/mark_as_unread_action"
-        android:showAsAction="never"
-    />
-    <item
-        android:id="@+id/select_text"
-        android:title="@string/select_text_action"
-        android:showAsAction="never"
-    />
-    <item
-        android:id="@+id/toggle_message_view_theme"
-        android:title="@string/message_view_theme_action_dark"
-        android:showAsAction="never"
-    />
-</menu>

res/menu/message_view_option.xml

@@ -1,15 +0,0 @@
-<?xml version="1.0" encoding="utf-8"?>
-<menu xmlns:android="http://schemas.android.com/apk/res/android">
-    <item
-        android:id="@+id/next_message"
-        android:title="@string/next_action"
-        android:icon="?attr/iconActionNextMessage"
-        android:showAsAction="always"
-    />
-    <item
-        android:id="@+id/previous_message"
-        android:title="@string/previous_action"
-        android:icon="?attr/iconActionPreviousMessage"
-        android:showAsAction="always"
-    />
-</menu>

src/com/fsck/k9/activity/MessageList.java

@@ -777,6 +777,14 @@ public class MessageList extends K9FragmentActivity implements MessageListFragme
                 return true;
             }
             // MessageView
+            case R.id.next_message: {
+                showNextMessage();
+                return true;
+            }
+            case R.id.previous_message: {
+                showPreviousMessage();
+                return true;
+            }
             case R.id.delete: {
                 mMessageViewFragment.onDelete();
                 return true;
@@ -897,6 +905,8 @@ public class MessageList extends K9FragmentActivity implements MessageListFragme
          */
 
         if (mMessageViewFragment == null || !mMessageViewFragment.isInitialized()) {
+            menu.findItem(R.id.next_message).setVisible(false);
+            menu.findItem(R.id.previous_message).setVisible(false);
             menu.findItem(R.id.delete).setVisible(false);
             menu.findItem(R.id.single_message_options).setVisible(false);
             menu.findItem(R.id.archive).setVisible(false);
@@ -907,6 +917,11 @@ public class MessageList extends K9FragmentActivity implements MessageListFragme
             menu.findItem(R.id.select_text).setVisible(false);
             menu.findItem(R.id.toggle_message_view_theme).setVisible(false);
         } else {
+            // hide prev/next buttons in split mode
+            if (mDisplayMode != DisplayMode.MESSAGE_VIEW) {
+                menu.findItem(R.id.next_message).setVisible(false);
+                menu.findItem(R.id.previous_message).setVisible(false);
+            }
             // Set title of menu item to switch to dark/light theme
             MenuItem toggleTheme = menu.findItem(R.id.toggle_message_view_theme);
             if (K9.getK9MessageViewTheme() == K9.THEME_DARK) {