Implement submenus on Android

* java/org/gnu/emacs/EmacsActivity.java (onCreate): Set the
default theme to Theme.DeviceDefault.NoActionBar if possible.
(onContextMenuClosed): Add hack for Android bug.
* java/org/gnu/emacs/EmacsContextMenu.java (EmacsContextMenu)
(onMenuItemClick): Set flag upon submenu selection.
(inflateMenuItems): Set onClickListener for submenus as well.
(display1): Clear new flag.
* java/org/gnu/emacs/EmacsDrawRectangle.java (perform): Fix
rectangle bounds.
* java/org/gnu/emacs/EmacsNative.java (EmacsNative):
* java/org/gnu/emacs/EmacsService.java (onCreate): Pass cache
directory.
(sync): New function.
* src/android.c (struct android_emacs_service): New method
`sync'.
(setEmacsParams, initEmacs): Handle cache directory.
(android_init_emacs_service): Initialize new method `sync'.
(android_sync): New function.
* src/androidfns.c (Fx_show_tip): Call both functions.
* src/androidgui.h: Update prototypes.
* src/androidmenu.c (struct android_menu_subprefix)
(android_free_subprefixes, android_menu_show): Handle submenu
prefixes correctly.
* src/androidterm.c (handle_one_android_event): Clear help echo
on MotionNotify like on X.
* src/menu.c (single_menu_item): Enable submenus on Android.

6 files changed, 177 insertions, 17 deletions

diff --git a/src/android.c b/src/android.c
index ed162a903ba..3a965286460 100644
--- a/src/android.c
+++ b/src/android.c
@@ -88,6 +88,7 @@ struct android_emacs_service
   jmethodID get_screen_height;
   jmethodID detect_mouse;
   jmethodID name_keysym;
+  jmethodID sync;
 };
 
 struct android_emacs_pixmap
@@ -116,15 +117,18 @@ static AAssetManager *asset_manager;
 /* Whether or not Emacs has been initialized.  */
 static int emacs_initialized;
 
-/* The path used to store site-lisp.  */
+/* The directory used to store site-lisp.  */
 char *android_site_load_path;
 
-/* The path used to store native libraries.  */
+/* The directory used to store native libraries.  */
 char *android_lib_dir;
 
-/* The path used to store game files.  */
+/* The directory used to store game files.  */
 char *android_game_path;
 
+/* The directory used to store temporary files.  */
+char *android_cache_dir;
+
 /* The display's pixel densities.  */
 double android_pixel_density_x, android_pixel_density_y;
 
@@ -911,6 +915,7 @@ JNIEXPORT void JNICALL
 NATIVE_NAME (setEmacsParams) (JNIEnv *env, jobject object,
                               jobject local_asset_manager,
                               jobject files_dir, jobject libs_dir,
+                              jobject cache_dir,
                               jfloat pixel_density_x,
                               jfloat pixel_density_y,
                               jobject emacs_service_object)
@@ -986,6 +991,20 @@ NATIVE_NAME (setEmacsParams) (JNIEnv *env, jobject object,
   (*env)->ReleaseStringUTFChars (env, (jstring) libs_dir,
                                  java_string);
 
+  java_string = (*env)->GetStringUTFChars (env, (jstring) cache_dir,
+                                           NULL);
+
+  if (!java_string)
+    emacs_abort ();
+
+  android_cache_dir = strdup ((const char *) java_string);
+
+  if (!android_files_dir)
+    emacs_abort ();
+
+  (*env)->ReleaseStringUTFChars (env, (jstring) cache_dir,
+                                 java_string);
+
   /* Calculate the site-lisp path.  */
 
   android_site_load_path = malloc (PATH_MAX + 1);
@@ -1083,6 +1102,7 @@ android_init_emacs_service (void)
   FIND_METHOD (get_screen_height, "getScreenHeight", "(Z)I");
   FIND_METHOD (detect_mouse, "detectMouse", "()Z");
   FIND_METHOD (name_keysym, "nameKeysym", "(I)Ljava/lang/String;");
+  FIND_METHOD (sync, "sync", "()V");
 #undef FIND_METHOD
 }
 
@@ -1216,6 +1236,9 @@ NATIVE_NAME (initEmacs) (JNIEnv *env, jobject object, jarray argv)
   /* Set HOME to the app data directory.  */
   setenv ("HOME", android_files_dir, 1);
 
+  /* Set TMPDIR to the temporary files directory.  */
+  setenv ("TMPDIR", android_cache_dir, 1);
+
   /* Set the cwd to that directory as well.  */
   if (chdir (android_files_dir))
     __android_log_print (ANDROID_LOG_WARN, __func__,
@@ -3519,6 +3542,15 @@ android_get_keysym_name (int keysym, char *name_return, size_t size)
   ANDROID_DELETE_LOCAL_REF (string);
 }
 
+void
+android_sync (void)
+{
+  (*android_java_env)->CallVoidMethod (android_java_env,
+                                       emacs_service,
+                                       service_class.sync);
+  android_exception_check ();
+}
+
 
 
 #undef faccessat
diff --git a/src/androidfns.c b/src/androidfns.c
index ab136bc2722..bb37c415069 100644
--- a/src/androidfns.c
+++ b/src/androidfns.c
@@ -26,6 +26,7 @@ along with GNU Emacs.  If not, see <https://www.gnu.org/licenses/>.  */
 #include "blockinput.h"
 #include "keyboard.h"
 #include "buffer.h"
+#include "androidgui.h"
 
 #ifndef ANDROID_STUBIFY
 
@@ -2282,6 +2283,13 @@ DEFUN ("x-show-tip", Fx_show_tip, Sx_show_tip, 1, 6, 0,
   android_map_raised (FRAME_ANDROID_WINDOW (tip_f));
   unblock_input ();
 
+  /* Synchronize with the UI thread.  This is required to prevent ugly
+     black splotches.  */
+  android_sync ();
+
+  /* Garbage the tip frame too.  */
+  SET_FRAME_GARBAGED (tip_f);
+
   w->must_be_updated_p = true;
   update_single_window (w);
   flush_frame (tip_f);
diff --git a/src/androidgui.h b/src/androidgui.h
index 0e075fda95e..9df5b073a7c 100644
--- a/src/androidgui.h
+++ b/src/androidgui.h
@@ -504,6 +504,7 @@ extern void android_move_resize_window (android_window, int, int,
 extern void android_map_raised (android_window);
 extern void android_translate_coordinates (android_window, int,
                                            int, int *, int *);
+extern void android_sync (void);
 
 #endif
 
diff --git a/src/androidmenu.c b/src/androidmenu.c
index 7522f9c5a52..6fb4963174b 100644
--- a/src/androidmenu.c
+++ b/src/androidmenu.c
@@ -28,6 +28,8 @@ along with GNU Emacs.  If not, see <https://www.gnu.org/licenses/>.  */
 
 #ifndef ANDROID_STUBIFY
 
+#include <android/log.h>
+
 /* Flag indicating whether or not a popup menu has been posted and not
    yet popped down.  */
 
@@ -188,6 +190,35 @@ android_process_events_for_menu (int *id)
   *id = x_display_list->menu_event_id;
 }
 
+/* Structure describing a ``subprefix'' in the menu.  */
+
+struct android_menu_subprefix
+{
+  /* The subprefix above.  */
+  struct android_menu_subprefix *last;
+
+  /* The subprefix itself.  */
+  Lisp_Object subprefix;
+};
+
+/* Free the subprefixes starting from *DATA.  */
+
+static void
+android_free_subprefixes (void *data)
+{
+  struct android_menu_subprefix **head, *subprefix;
+
+  head = data;
+
+  while (*head)
+    {
+      subprefix = *head;
+      *head = subprefix->last;
+
+      xfree (subprefix);
+    }
+}
+
 Lisp_Object
 android_menu_show (struct frame *f, int x, int y, int menuflags,
                    Lisp_Object title, const char **error_name)
@@ -198,13 +229,15 @@ android_menu_show (struct frame *f, int x, int y, int menuflags,
   Lisp_Object pane_name, prefix;
   const char *pane_string;
   specpdl_ref count, count1;
-  Lisp_Object item_name, enable, def, tem;
+  Lisp_Object item_name, enable, def, tem, entry;
   jmethodID method;
   jobject store;
   bool rc;
   jobject window;
-  int id, item_id;
+  int id, item_id, submenu_depth;
   struct android_dismiss_menu_data data;
+  struct android_menu_subprefix *subprefix, *temp_subprefix;
+  struct android_menu_subprefix *subprefix_1;
 
   count = SPECPDL_INDEX ();
 
@@ -232,7 +265,7 @@ android_menu_show (struct frame *f, int x, int y, int menuflags,
   android_push_local_frame ();
 
   /* Iterate over the menu.  */
-  i = 0;
+  i = 0, submenu_depth = 0;
 
   while (i < menu_items_used)
     {
@@ -241,6 +274,7 @@ android_menu_show (struct frame *f, int x, int y, int menuflags,
           /* This is the start of a new submenu.  However, it can be
              ignored here.  */
           i += 1;
+          submenu_depth += 1;
         }
       else if (EQ (AREF (menu_items, i), Qlambda))
         {
@@ -256,9 +290,18 @@ android_menu_show (struct frame *f, int x, int y, int menuflags,
           if (store != context_menu)
             ANDROID_DELETE_LOCAL_REF (store);
           i += 1;
+          submenu_depth -= 1;
 
-          eassert (current_context_menu);
+          if (!current_context_menu || submenu_depth < 0)
+            {
+              __android_log_print (ANDROID_LOG_FATAL, __func__,
+                                   "unbalanced submenu pop in menu_items");
+              emacs_abort ();
+            }
         }
+      else if (EQ (AREF (menu_items, i), Qt)
+               && submenu_depth != 0)
+        i += MENU_ITEMS_PANE_LENGTH;
       else if (EQ (AREF (menu_items, i), Qquote))
         i += 1;
       else if (EQ (AREF (menu_items, i), Qt))
@@ -300,8 +343,8 @@ android_menu_show (struct frame *f, int x, int y, int menuflags,
           /* This is an actual menu item (or submenu).  Add it to the
              menu.  */
 
-          if (i + MENU_ITEMS_ITEM_LENGTH < menu_items_used &&
-              NILP (AREF (menu_items, i + MENU_ITEMS_ITEM_LENGTH)))
+          if (i + MENU_ITEMS_ITEM_LENGTH < menu_items_used
+              && NILP (AREF (menu_items, i + MENU_ITEMS_ITEM_LENGTH)))
             {
               /* This is a submenu.  Add it.  */
               title_string = (!NILP (item_name)
@@ -312,7 +355,7 @@ android_menu_show (struct frame *f, int x, int y, int menuflags,
                 = (*android_java_env)->CallObjectMethod (android_java_env,
                                                          current_context_menu,
                                                          menu_class.add_submenu,
-                                                         title_string);
+                                                         title_string, NULL);
               android_exception_check ();
 
               if (store != context_menu)
@@ -385,13 +428,78 @@ android_menu_show (struct frame *f, int x, int y, int menuflags,
     /* This means no menu item was selected.  */
     goto finish;
 
-  /* id is an index into menu_items.  Check that it remains
-     valid.  */
+  /* This means the id is invalid.  */
   if (id >= ASIZE (menu_items))
     goto finish;
 
   /* Now return the menu item at that location.  */
-  tem = AREF (menu_items, id);
+  tem = Qnil;
+  subprefix = NULL;
+  record_unwind_protect_ptr (android_free_subprefixes, &subprefix);
+
+  /* Find the selected item, and its pane, to return
+     the proper value.  */
+
+  prefix = entry = Qnil;
+  i = 0;
+  while (i < menu_items_used)
+    {
+      if (NILP (AREF (menu_items, i)))
+        {
+          temp_subprefix = xmalloc (sizeof *temp_subprefix);
+          temp_subprefix->last = subprefix;
+          subprefix = temp_subprefix;
+          subprefix->subprefix = prefix;
+
+          prefix = entry;
+          i++;
+        }
+      else if (EQ (AREF (menu_items, i), Qlambda))
+        {
+          prefix = subprefix->subprefix;
+          temp_subprefix = subprefix->last;
+          xfree (subprefix);
+          subprefix = temp_subprefix;
+
+          i++;
+        }
+      else if (EQ (AREF (menu_items, i), Qt))
+        {
+          prefix
+            = AREF (menu_items, i + MENU_ITEMS_PANE_PREFIX);
+          i += MENU_ITEMS_PANE_LENGTH;
+        }
+      /* Ignore a nil in the item list.
+         It's meaningful only for dialog boxes.  */
+      else if (EQ (AREF (menu_items, i), Qquote))
+        i += 1;
+      else
+        {
+          entry = AREF (menu_items, i + MENU_ITEMS_ITEM_VALUE);
+
+          if (i + MENU_ITEMS_ITEM_VALUE == id)
+            {
+              if (menuflags & MENU_KEYMAPS)
+                {
+                  entry = list1 (entry);
+
+                  if (!NILP (prefix))
+                    entry = Fcons (prefix, entry);
+
+                  for (subprefix_1 = subprefix; subprefix_1;
+                       subprefix_1 = subprefix_1->last)
+                    if (!NILP (subprefix_1->subprefix))
+                      entry = Fcons (subprefix_1->subprefix, entry);
+                }
+
+              tem = entry;
+            }
+          i += MENU_ITEMS_ITEM_LENGTH;
+        }
+    }
+
+  Fprint (tem, Qexternal_debugging_output);
+
   unblock_input ();
   return unbind_to (count, tem);
 
diff --git a/src/androidterm.c b/src/androidterm.c
index 4017fec60a5..6f452a52d85 100644
--- a/src/androidterm.c
+++ b/src/androidterm.c
@@ -689,6 +689,16 @@ handle_one_android_event (struct android_display_info *dpyinfo,
       goto OTHER;
 
     case ANDROID_MOTION_NOTIFY:
+
+      previous_help_echo_string = help_echo_string;
+      help_echo_string = Qnil;
+
+      if (hlinfo->mouse_face_hidden)
+        {
+          hlinfo->mouse_face_hidden = false;
+          clear_mouse_face (hlinfo);
+        }
+
       f = any;
 
       if (f)
diff --git a/src/menu.c b/src/menu.c
index 73d4215b94b..e1f899858d3 100644
--- a/src/menu.c
+++ b/src/menu.c
@@ -167,7 +167,7 @@ ensure_menu_items (int items)
     }
 }
 
-#ifdef HAVE_EXT_MENU_BAR
+#if defined HAVE_EXT_MENU_BAR || defined HAVE_ANDROID
 
 /* Begin a submenu.  */
 
@@ -191,7 +191,7 @@ push_submenu_end (void)
   menu_items_submenu_depth--;
 }
 
-#endif /* HAVE_EXT_MENU_BAR */
+#endif /* HAVE_EXT_MENU_BAR || HAVE_ANDROID */
 
 /* Indicate boundary between left and right.  */
 
@@ -420,8 +420,9 @@ single_menu_item (Lisp_Object key, Lisp_Object item, Lisp_Object dummy, void *sk
                   AREF (item_properties, ITEM_PROPERTY_SELECTED),
                   AREF (item_properties, ITEM_PROPERTY_HELP));
 
-#if defined (USE_X_TOOLKIT) || defined (USE_GTK) || defined (HAVE_NS) \
-  || defined (HAVE_NTGUI) || defined (HAVE_HAIKU) || defined (HAVE_PGTK)
+#if defined (USE_X_TOOLKIT) || defined (USE_GTK) || defined (HAVE_NS)   \
+  || defined (HAVE_NTGUI) || defined (HAVE_HAIKU) || defined (HAVE_PGTK) \
+  || defined (HAVE_ANDROID)
   /* Display a submenu using the toolkit.  */
   if (FRAME_WINDOW_P (XFRAME (Vmenu_updating_frame))
       && ! (NILP (map) || NILP (enabled)))