feature/android 7e8904e7968: Use context menu header titles on Android

[Po Lu]

branch: feature/android
commit 7e8904e796807e3b8bfc20ed45135c53d8a86f50
Author: Po Lu <luangruo@yahoo.com>
Commit: Po Lu <luangruo@yahoo.com>

    Use context menu header titles on Android
    
    * java/org/gnu/emacs/EmacsContextMenu.java (EmacsContextMenu):
    New field `title'.
    (addSubmenu): New arg TITLE.  Set that field.
    (expandTo): Set MENU's header title if it's a context menu.
    * src/androidmenu.c (android_init_emacs_context_menu): Adjust
    signature of `createContextMenu'.
    (android_menu_show): Use TITLE instead of pane titles if there's
    only one pane.
---
 java/org/gnu/emacs/EmacsContextMenu.java | 26 +++++++++++++++++++++++---
 src/androidmenu.c                        | 27 +++++++++++++++++++++++++--
 2 files changed, 48 insertions(+), 5 deletions(-)

diff --git a/java/org/gnu/emacs/EmacsContextMenu.java 
b/java/org/gnu/emacs/EmacsContextMenu.java
index eb83016c849..46eddeeda3d 100644
--- a/java/org/gnu/emacs/EmacsContextMenu.java
+++ b/java/org/gnu/emacs/EmacsContextMenu.java
@@ -27,6 +27,7 @@ import android.content.Intent;
 
 import android.os.Build;
 
+import android.view.ContextMenu;
 import android.view.Menu;
 import android.view.MenuItem;
 import android.view.View;
@@ -130,18 +131,27 @@ public final class EmacsContextMenu
     }
   };
 
+  /* List of menu items contained in this menu.  */
   public List<Item> menuItems;
+
+  /* The parent context menu, or NULL if none.  */
   private EmacsContextMenu parent;
 
+  /* The title of this context menu, or NULL if none.  */
+  private String title;
+
+
+
   /* Create a context menu with no items inside and the title TITLE,
      which may be NULL.  */
 
   public static EmacsContextMenu
-  createContextMenu ()
+  createContextMenu (String title)
   {
     EmacsContextMenu menu;
 
     menu = new EmacsContextMenu ();
+    menu.title = title;
     menu.menuItems = new ArrayList<Item> ();
 
     return menu;
@@ -204,7 +214,7 @@ public final class EmacsContextMenu
     item.itemID = 0;
     item.itemName = itemName;
     item.tooltip = tooltip;
-    item.subMenu = createContextMenu ();
+    item.subMenu = createContextMenu (itemName);
     item.subMenu.parent = this;
 
     menuItems.add (item);
@@ -287,12 +297,22 @@ public final class EmacsContextMenu
 
   /* Enter the items in this context menu to MENU.
      Assume that MENU will be displayed in VIEW; this may lead to
-     popupMenu being called on VIEW if a submenu is selected.  */
+     popupMenu being called on VIEW if a submenu is selected.
+
+     If MENU is a ContextMenu, set its header title to the one
+     contained in this object.  */
 
   public void
   expandTo (Menu menu, EmacsView view)
   {
     inflateMenuItems (menu, view);
+
+    /* See if menu is a ContextMenu and a title is set.  */
+    if (title == null || !(menu instanceof ContextMenu))
+      return;
+
+    /* Set its title to this.title.  */
+    ((ContextMenu) menu).setHeaderTitle (title);
   }
 
   /* Return the parent or NULL.  */
diff --git a/src/androidmenu.c b/src/androidmenu.c
index 75710486c75..94e3f646b44 100644
--- a/src/androidmenu.c
+++ b/src/androidmenu.c
@@ -101,7 +101,8 @@ android_init_emacs_context_menu (void)
   eassert (menu_class.c_name);
 
   FIND_METHOD_STATIC (create_context_menu, "createContextMenu",
-                     "()Lorg/gnu/emacs/EmacsContextMenu;");
+                     "(Ljava/lang/String;)"
+                     "Lorg/gnu/emacs/EmacsContextMenu;");
 
   FIND_METHOD (add_item, "addItem", "(ILjava/lang/String;ZZZ"
               "Ljava/lang/String;Z)V");
@@ -269,12 +270,26 @@ android_menu_show (struct frame *f, int x, int y, int 
menuflags,
   /* Push the first local frame.  */
   android_push_local_frame ();
 
+  /* Set title_string to a Java string containing TITLE if non-nil.
+     If the menu consists of more than one pane, replace the title
+     with the pane header item so that the menu looks consistent.  */
+
+  title_string = NULL;
+  if (STRINGP (title) && menu_items_n_panes < 2)
+    title_string = android_build_string (title);
+
   /* Push the first local frame for the context menu.  */
   method = menu_class.create_context_menu;
   current_context_menu = context_menu
     = (*android_java_env)->CallStaticObjectMethod (android_java_env,
                                                   menu_class.class,
-                                                  method);
+                                                  method,
+                                                  title_string);
+
+  /* Delete the unused title reference.  */
+
+  if (title_string)
+    ANDROID_DELETE_LOCAL_REF (title_string);
 
   /* Push the second local frame for temporaries.  */
   count1 = SPECPDL_INDEX ();
@@ -322,6 +337,13 @@ android_menu_show (struct frame *f, int x, int y, int 
menuflags,
        i += 1;
       else if (EQ (AREF (menu_items, i), Qt))
        {
+         /* If the menu contains a single pane, then the pane is
+            actually TITLE.  Don't duplicate the text within the
+            context menu title.  */
+
+         if (menu_items_n_panes < 2)
+           goto next_item;
+
          /* This is a new pane.  Switch back to the topmost context
             menu.  */
          if (current_context_menu != context_menu)
@@ -348,6 +370,7 @@ android_menu_show (struct frame *f, int x, int y, int 
menuflags,
          android_exception_check ();
          ANDROID_DELETE_LOCAL_REF (temp);
 
+       next_item:
          i += MENU_ITEMS_PANE_LENGTH;
        }
       else