Implement toolkit menus on Android

* java/org/gnu/emacs/EmacsActivity.java (onContextMenuClosed):
New function.
* java/org/gnu/emacs/EmacsContextMenu.java (EmacsContextMenu):
New field `itemAlreadySelected'.
(onMenuItemClick): New function.
(inflateMenuItems): Attach onClickListener as appropriate.
(display1): Clear itemAlreadySelected.
(display): Fix runnable synchronization.
* java/org/gnu/emacs/EmacsNative.java (sendContextMenu): New
function.
* java/org/gnu/emacs/EmacsView.java (popupMenu):
(cancelPopupMenu): Set popupactive correctly.

* src/android.c (android_run_select_thread): Fix android_select
again.
(android_wait_event): New function.
* src/android.h: Update prototypes.
* src/androidgui.h (enum android_event_type): New
`ANDROID_CONTEXT_MENU' event.
(struct android_menu_event, union android_event): Add new event.

* src/androidmenu.c (struct android_emacs_context_menu): New
structure.
(android_init_emacs_context_menu): Add `dismiss' method.
(struct android_dismiss_menu_data): New structure.
(android_dismiss_menu, android_process_events_for_menu): New
functions.
(android_menu_show): Set an actual item ID.
(popup_activated): Define when stubify as well.
(Fmenu_or_popup_active_p): New function.
(syms_of_androidmenu): New function.

* src/androidterm.c (handle_one_android_event): Handle context
menu events.
* src/androidterm.h (struct android_display_info): New field for
menu item ID.
* src/emacs.c (android_emacs_init): Call syms_of_androidmenu.
* src/xdisp.c (note_mouse_highlight): Return if popup_activated
on Android as well.

8 files changed, 181 insertions, 9 deletions

diff --git a/src/android.c b/src/android.c
index 5e5e28c60ca..ed162a903ba 100644
--- a/src/android.c
+++ b/src/android.c
@@ -236,7 +236,7 @@ static sem_t android_pselect_sem, android_pselect_start_sem;
 static void *
 android_run_select_thread (void *data)
 {
-  sigset_t signals;
+  sigset_t signals, sigset;
   int rc;
 
   sigfillset (&signals);
@@ -259,7 +259,11 @@ android_run_select_thread (void *data)
 
       /* Make sure SIGUSR1 can always wake pselect up.  */
       if (android_pselect_sigset)
-        sigdelset (android_pselect_sigset, SIGUSR1);
+        {
+          sigset = *android_pselect_sigset;
+          sigdelset (&sigset, SIGUSR1);
+          android_pselect_sigset = &sigset;
+        }
       else
         android_pselect_sigset = &signals;
 
@@ -356,6 +360,23 @@ android_pending (void)
   return i;
 }
 
+/* Wait for events to become available synchronously.  Return once an
+   event arrives.  */
+
+void
+android_wait_event (void)
+{
+  pthread_mutex_lock (&event_queue.mutex);
+
+  /* Wait for events to appear if there are none available to
+     read.  */
+  if (!event_queue.num_events)
+    pthread_cond_wait (&event_queue.read_var,
+                       &event_queue.mutex);
+
+  pthread_mutex_unlock (&event_queue.mutex);
+}
+
 void
 android_next_event (union android_event *event_return)
 {
@@ -1472,6 +1493,8 @@ NATIVE_NAME (sendIconified) (JNIEnv *env, jobject object,
 
   event.iconified.type = ANDROID_ICONIFIED;
   event.iconified.window = window;
+
+  android_write_event (&event);
 }
 
 extern JNIEXPORT void JNICALL
@@ -1482,6 +1505,21 @@ NATIVE_NAME (sendDeiconified) (JNIEnv *env, jobject object,
 
   event.iconified.type = ANDROID_DEICONIFIED;
   event.iconified.window = window;
+
+  android_write_event (&event);
+}
+
+extern JNIEXPORT void JNICALL
+NATIVE_NAME (sendContextMenu) (JNIEnv *env, jobject object,
+                               jshort window, jint menu_event_id)
+{
+  union android_event event;
+
+  event.menu.type = ANDROID_CONTEXT_MENU;
+  event.menu.window = window;
+  event.menu.menu_event_id = menu_event_id;
+
+  android_write_event (&event);
 }
 
 #pragma clang diagnostic pop
diff --git a/src/android.h b/src/android.h
index 98f2494e9a3..e68e0a51fbf 100644
--- a/src/android.h
+++ b/src/android.h
@@ -89,6 +89,7 @@ extern jstring android_build_string (Lisp_Object);
 extern void android_exception_check (void);
 
 extern void android_get_keysym_name (int, char *, size_t);
+extern void android_wait_event (void);
 
 
 
diff --git a/src/androidgui.h b/src/androidgui.h
index 8450a1f637b..0e075fda95e 100644
--- a/src/androidgui.h
+++ b/src/androidgui.h
@@ -233,6 +233,7 @@ enum android_event_type
     ANDROID_WHEEL,
     ANDROID_ICONIFIED,
     ANDROID_DEICONIFIED,
+    ANDROID_CONTEXT_MENU,
   };
 
 struct android_any_event
@@ -371,6 +372,18 @@ struct android_iconify_event
   android_window window;
 };
 
+struct android_menu_event
+{
+  /* Type of the event.  */
+  enum android_event_type type;
+
+  /* Window associated with the event.  Always None.  */
+  android_window window;
+
+  /* Menu event ID.  */
+  int menu_event_id;
+};
+
 union android_event
 {
   enum android_event_type type;
@@ -395,6 +408,9 @@ union android_event
   /* This has no parallel in X because Android doesn't have window
      properties.  */
   struct android_iconify_event iconified;
+
+  /* This is only used to transmit selected menu items.  */
+  struct android_menu_event menu;
 };
 
 enum
diff --git a/src/androidmenu.c b/src/androidmenu.c
index 0f0c6f4ef1f..7522f9c5a52 100644
--- a/src/androidmenu.c
+++ b/src/androidmenu.c
@@ -54,6 +54,7 @@ struct android_emacs_context_menu
   jmethodID add_pane;
   jmethodID parent;
   jmethodID display;
+  jmethodID dismiss;
 };
 
 /* Identifiers associated with the EmacsContextMenu class.  */
@@ -101,6 +102,7 @@ android_init_emacs_context_menu (void)
   FIND_METHOD (add_pane, "addPane", "(Ljava/lang/String;)V");
   FIND_METHOD (parent, "parent", "()Lorg/gnu/emacs/EmacsContextMenu;");
   FIND_METHOD (display, "display", "(Lorg/gnu/emacs/EmacsWindow;II)Z");
+  FIND_METHOD (dismiss, "dismiss", "(Lorg/gnu/emacs/EmacsWindow;)V");
 
 #undef FIND_METHOD
 #undef FIND_METHOD_STATIC
@@ -130,6 +132,62 @@ android_push_local_frame (void)
   record_unwind_protect_void (android_unwind_local_frame);
 }
 
+/* Data for android_dismiss_menu.  */
+
+struct android_dismiss_menu_data
+{
+  /* The menu object.  */
+  jobject menu;
+
+  /* The window object.  */
+  jobject window;
+};
+
+/* Cancel the context menu passed in POINTER.  Also, clear
+   popup_activated_flag.  */
+
+static void
+android_dismiss_menu (void *pointer)
+{
+  struct android_dismiss_menu_data *data;
+
+  data = pointer;
+  (*android_java_env)->CallVoidMethod (android_java_env,
+                                       data->menu,
+                                       menu_class.dismiss,
+                                       data->window);
+  popup_activated_flag = 0;
+}
+
+/* Recursively process events until a ANDROID_CONTEXT_MENU event
+   arrives.  Then, return the item ID specified in the event in
+   *ID.  */
+
+static void
+android_process_events_for_menu (int *id)
+{
+  /* Set menu_event_id to -1; handle_one_android_event will set it to
+     the event ID upon receiving a context menu event.  This can cause
+     a non-local exit.  */
+  x_display_list->menu_event_id = -1;
+
+  /* Now wait for the menu event ID to change.  */
+  while (x_display_list->menu_event_id == -1)
+    {
+      /* Wait for events to become available.  */
+      android_wait_event ();
+
+      /* Process pending signals.  */
+      process_pending_signals ();
+
+      /* Maybe quit.  */
+      maybe_quit ();
+    }
+
+  /* Return the ID.  */
+  *id = x_display_list->menu_event_id;
+}
+
 Lisp_Object
 android_menu_show (struct frame *f, int x, int y, int menuflags,
                    Lisp_Object title, const char **error_name)
@@ -140,11 +198,13 @@ 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;
+  Lisp_Object item_name, enable, def, tem;
   jmethodID method;
   jobject store;
   bool rc;
   jobject window;
+  int id, item_id;
+  struct android_dismiss_menu_data data;
 
   count = SPECPDL_INDEX ();
 
@@ -266,6 +326,12 @@ android_menu_show (struct frame *f, int x, int y, int menuflags,
             ;
           else
             {
+              /* Compute the item ID.  This is the index of value.
+                 Make sure it doesn't overflow.  */
+
+              if (!INT_ADD_OK (0, i + MENU_ITEMS_ITEM_VALUE, &item_id))
+                memory_full (i + MENU_ITEMS_ITEM_VALUE * sizeof (Lisp_Object));
+
               /* Add this menu item with the appropriate state.  */
 
               title_string = (!NILP (item_name)
@@ -274,7 +340,7 @@ android_menu_show (struct frame *f, int x, int y, int menuflags,
               (*android_java_env)->CallVoidMethod (android_java_env,
                                                    current_context_menu,
                                                    menu_class.add_item,
-                                                   (jint) 1,
+                                                   (jint) item_id,
                                                    title_string,
                                                    (jboolean) !NILP (enable));
               android_exception_check ();
@@ -295,6 +361,7 @@ android_menu_show (struct frame *f, int x, int y, int menuflags,
                                    ANDROID_HANDLE_WINDOW);
   rc = (*android_java_env)->CallBooleanMethod (android_java_env,
                                                context_menu,
+                                               menu_class.display,
                                                window, (jint) x,
                                                (jint) y);
   android_exception_check ();
@@ -303,25 +370,54 @@ android_menu_show (struct frame *f, int x, int y, int menuflags,
     /* This means displaying the menu failed.  */
     goto finish;
 
-#if 0
-  record_unwind_protect_ptr (android_dismiss_menu, &context_menu);
+  /* Make sure the context menu is always dismissed.  */
+  data.menu = context_menu;
+  data.window = window;
+  record_unwind_protect_ptr (android_dismiss_menu, &data);
 
-  /* Otherwise, loop waiting for the menu event to arrive.  */
+  /* Next, process events waiting for something to be selected.  */
+  popup_activated_flag = 1;
+  unblock_input ();
   android_process_events_for_menu (&id);
+  block_input ();
 
   if (!id)
     /* This means no menu item was selected.  */
     goto finish;
 
-#endif
+  /* id is an index into menu_items.  Check that it remains
+     valid.  */
+  if (id >= ASIZE (menu_items))
+    goto finish;
+
+  /* Now return the menu item at that location.  */
+  tem = AREF (menu_items, id);
+  unblock_input ();
+  return unbind_to (count, tem);
 
  finish:
   unblock_input ();
   return unbind_to (count, Qnil);
 }
 
+#else
+
+int
+popup_activated (void)
+{
+  return 0;
+}
+
 #endif
 
+DEFUN ("menu-or-popup-active-p", Fmenu_or_popup_active_p,
+       Smenu_or_popup_active_p, 0, 0, 0,
+       doc: /* SKIP: real doc in xfns.c.  */)
+  (void)
+{
+  return (popup_activated ()) ? Qt : Qnil;
+}
+
 void
 init_androidmenu (void)
 {
@@ -329,3 +425,9 @@ init_androidmenu (void)
   android_init_emacs_context_menu ();
 #endif
 }
+
+void
+syms_of_androidmenu (void)
+{
+  defsubr (&Smenu_or_popup_active_p);
+}
diff --git a/src/androidterm.c b/src/androidterm.c
index 002d39af707..4017fec60a5 100644
--- a/src/androidterm.c
+++ b/src/androidterm.c
@@ -1125,6 +1125,14 @@ handle_one_android_event (struct android_display_info *dpyinfo,
       XSETFRAME (inev.ie.frame_or_window, any);
       goto OTHER;
 
+      /* Context menu handling.  */
+    case ANDROID_CONTEXT_MENU:
+
+      if (dpyinfo->menu_event_id == -1)
+        dpyinfo->menu_event_id = event->menu.menu_event_id;
+
+      goto OTHER;
+
     default:
       goto OTHER;
     }
diff --git a/src/androidterm.h b/src/androidterm.h
index e83e32a5854..9aa09877196 100644
--- a/src/androidterm.h
+++ b/src/androidterm.h
@@ -132,6 +132,10 @@ struct android_display_info
 
   /* The time of the last mouse movement.  */
   Time last_mouse_movement_time;
+
+  /* ID of the last menu event received.  -1 means Emacs is waiting
+     for a context menu event.  */
+  int menu_event_id;
 };
 
 /* Structure representing a single tool (finger or stylus) pressed
@@ -407,6 +411,7 @@ extern void android_finalize_font_entity (struct font_entity *);
 extern Lisp_Object android_menu_show (struct frame *, int, int, int,
                                       Lisp_Object, const char **);
 extern void init_androidmenu (void);
+extern void syms_of_androidmenu (void);
 
 /* Defined in sfntfont-android.c.  */
 
diff --git a/src/emacs.c b/src/emacs.c
index 8f5be53aad9..f4973c70610 100644
--- a/src/emacs.c
+++ b/src/emacs.c
@@ -2397,6 +2397,7 @@ Using an Emacs configured with --with-x-toolkit=lucid does not have this problem
 #ifdef HAVE_ANDROID
       syms_of_androidterm ();
       syms_of_androidfns ();
+      syms_of_androidmenu ();
       syms_of_fontset ();
 #if !defined ANDROID_STUBIFY
       syms_of_androidfont ();
diff --git a/src/xdisp.c b/src/xdisp.c
index b9ee102af26..262a823f899 100644
--- a/src/xdisp.c
+++ b/src/xdisp.c
@@ -34959,7 +34959,8 @@ note_mouse_highlight (struct frame *f, int x, int y)
   struct buffer *b;
 
   /* When a menu is active, don't highlight because this looks odd.  */
-#if defined (HAVE_X_WINDOWS) || defined (HAVE_NS) || defined (MSDOS)
+#if defined (HAVE_X_WINDOWS) || defined (HAVE_NS) || defined (MSDOS) \
+  || defined (HAVE_ANDROID)
   if (popup_activated ())
     return;
 #endif