Improve transition between plugin and WPS

Eliminate flashing when plugins are launched
from WPS, by not enabling the SBS, and by
deferring other lcd updates.

Also prevents flashing root menu activity when
returning from plugins.

Change-Id: I7d761867027f2275c4ab8e16ada3107c7ba0be6e

6 files changed, 109 insertions, 40 deletions

diff --git a/apps/gui/wps.c b/apps/gui/wps.c
index 430746cc8d..fe4bcf3213 100644
--- a/apps/gui/wps.c
+++ b/apps/gui/wps.c
@@ -63,6 +63,7 @@
 #include "wps.h"
 #include "statusbar-skinned.h"
 #include "skin_engine/wps_internals.h"
+#include "open_plugin.h"
 
 #define RESTORE_WPS_INSTANTLY       0l
 #define RESTORE_WPS_NEXT_SECOND     ((long)(HZ+current_tick))
@@ -514,16 +515,19 @@ static void wps_lcd_activation_hook(unsigned short id, void *param)
 }
 #endif
 
-static void gwps_leave_wps(void)
+static void gwps_leave_wps(bool theme_enabled)
 {
     FOR_NB_SCREENS(i)
     {
         struct gui_wps *gwps = skin_get_gwps(WPS, i);
         gwps->display->scroll_stop();
+        if (theme_enabled)
+        {
 #ifdef HAVE_BACKDROP_IMAGE
-        skin_backdrop_show(sb_get_backdrop(i));
+            skin_backdrop_show(sb_get_backdrop(i));
 #endif
-        viewportmanager_theme_undo(i, skin_has_sbs(gwps));
+            viewportmanager_theme_undo(i, skin_has_sbs(gwps));
+        }
     }
 
 #if defined(HAVE_LCD_ENABLE) || defined(HAVE_LCD_SLEEP)
@@ -539,7 +543,7 @@ static void gwps_leave_wps(void)
 
 /*
  * display the wps on entering or restoring */
-static void gwps_enter_wps(void)
+static void gwps_enter_wps(bool theme_enabled)
 {
     struct gui_wps *gwps;
     struct screen *display;
@@ -548,7 +552,8 @@ static void gwps_enter_wps(void)
         gwps = skin_get_gwps(WPS, i);
         display = gwps->display;
         display->scroll_stop();
-        viewportmanager_theme_enable(i, skin_has_sbs(gwps), NULL);
+        if (theme_enabled)
+            viewportmanager_theme_enable(i, skin_has_sbs(gwps), NULL);
 
         /* Update the values in the first (default) viewport - in case the user
            has modified the statusbar or colour settings */
@@ -609,7 +614,7 @@ void wps_do_playpause(bool updatewps)
  *      b)  return with a value evaluated by root_menu.c, in this case the wps
  *          is really left, and root_menu will handle the next screen
  *
- * In either way, call gwps_leave_wps(), in order to restore the correct
+ * In either way, call gwps_leave_wps(true), in order to restore the correct
  * "main screen" backdrops and statusbars
  */
 long gui_wps_show(void)
@@ -632,6 +637,7 @@ long gui_wps_show(void)
 
     while ( 1 )
     {
+        bool theme_enabled = true;
         bool audio_paused = (audio_status() & AUDIO_STATUS_PAUSE)?true:false;
 
         /* did someone else (i.e power thread) change audio pause mode? */
@@ -693,23 +699,59 @@ long gui_wps_show(void)
             case ACTION_WPS_CONTEXT:
             {
                 bool hotkey = button == ACTION_WPS_HOTKEY;
-                gwps_leave_wps();
-                int retval = onplay(state->id3->path,
+
+#ifdef HAVE_HOTKEY
+                if (hotkey && global_settings.hotkey_wps == HOTKEY_PLUGIN)
+                {
+                    /* leave WPS without re-enabling theme */
+                    theme_enabled = false;
+                    gwps_leave_wps(theme_enabled);
+                    onplay(state->id3->path,
                            FILE_ATTR_AUDIO, CONTEXT_WPS, hotkey);
-                /* if music is stopped in the context menu we want to exit the wps */
-                if (retval == ONPLAY_MAINMENU
-                    || !audio_status())
-                    return GO_TO_ROOT;
-                else if (retval == ONPLAY_PLAYLIST)
-                    return GO_TO_PLAYLIST_VIEWER;
-                else if (retval == ONPLAY_PLUGIN)
-                    return GO_TO_PLUGIN;
+                    if (!audio_status())
+                    {
+                        /* re-enable theme since we're returning to SBS */
+                        FOR_NB_SCREENS(i)
+                        {
+                            struct gui_wps *gwps = skin_get_gwps(WPS, i);
+#ifdef HAVE_BACKDROP_IMAGE
+                            skin_backdrop_show(sb_get_backdrop(i));
+#endif
+                            viewportmanager_theme_undo(i, skin_has_sbs(gwps));
+                        }
+                        return GO_TO_ROOT;
+                    }
+                }
+                else
+#endif
+                {
+                    gwps_leave_wps(true);
+                    int retval = onplay(state->id3->path,
+                           FILE_ATTR_AUDIO, CONTEXT_WPS, hotkey);
+                    /* if music is stopped in the context menu we want to exit the wps */
+                    if (retval == ONPLAY_MAINMENU
+                        || !audio_status())
+                        return GO_TO_ROOT;
+                    else if (retval == ONPLAY_PLAYLIST)
+                        return GO_TO_PLAYLIST_VIEWER;
+                    else if (retval == ONPLAY_PLUGIN)
+                    {
+                        FOR_NB_SCREENS(i)
+                        {
+                            struct gui_wps *gwps = skin_get_gwps(WPS, i);
+                            viewportmanager_theme_enable(i, skin_has_sbs(gwps), NULL);
+                        }
+                        theme_enabled = false;
+                        open_plugin_run(ID2P(LANG_OPEN_PLUGIN_SET_WPS_CONTEXT_PLUGIN));
+                    }
+                }
+
                 restore = true;
             }
             break;
 
             case ACTION_WPS_BROWSE:
-                gwps_leave_wps();
+                gwps_leave_wps(true);
                 return GO_TO_PREVIOUS_BROWSER;
                 break;
 
@@ -852,7 +894,7 @@ long gui_wps_show(void)
                 break;
             /* menu key functions */
             case ACTION_WPS_MENU:
-                gwps_leave_wps();
+                gwps_leave_wps(true);
                 return GO_TO_ROOT;
                 break;
 
@@ -860,7 +902,7 @@ long gui_wps_show(void)
 #ifdef HAVE_QUICKSCREEN
             case ACTION_WPS_QUICKSCREEN:
             {
-                gwps_leave_wps();
+                gwps_leave_wps(true);
                 bool enter_shortcuts_menu = global_settings.shortcuts_replaces_qs;
                 if (!enter_shortcuts_menu)
                 {
@@ -889,7 +931,7 @@ long gui_wps_show(void)
 #ifdef HAVE_PITCHCONTROL
             case ACTION_WPS_PITCHSCREEN:
             {
-                gwps_leave_wps();
+                gwps_leave_wps(true);
                 if (1 == gui_syncpitchscreen_run())
                     return GO_TO_ROOT;
                 restore = true;
@@ -917,7 +959,7 @@ long gui_wps_show(void)
                 break;
 
             case ACTION_WPS_LIST_BOOKMARKS:
-                gwps_leave_wps();
+                gwps_leave_wps(true);
                 if (bookmark_load_menu() == BOOKMARK_USB_CONNECTED)
                 {
                     return GO_TO_ROOT;
@@ -926,14 +968,14 @@ long gui_wps_show(void)
                 break;
 
             case ACTION_WPS_CREATE_BOOKMARK:
-                gwps_leave_wps();
+                gwps_leave_wps(true);
                 bookmark_create_menu();
                 restore = true;
                 break;
 
             case ACTION_WPS_ID3SCREEN:
             {
-                gwps_leave_wps();
+                gwps_leave_wps(true);
                 if (browse_id3(audio_current_track(),
                         playlist_get_display_index(),
                         playlist_amount()))
@@ -956,7 +998,7 @@ long gui_wps_show(void)
                 break;
 #endif
             case ACTION_WPS_VIEW_PLAYLIST:
-                gwps_leave_wps();
+                gwps_leave_wps(true);
                 return GO_TO_PLAYLIST_VIEWER;
                 break;
             default:
@@ -965,7 +1007,7 @@ long gui_wps_show(void)
                     case SYS_USB_CONNECTED:
                     case SYS_CALL_INCOMING:
                     case BUTTON_MULTIMEDIA_STOP:
-                        gwps_leave_wps();
+                        gwps_leave_wps(true);
                         return GO_TO_ROOT;
                 }
                 update = true;
@@ -1003,7 +1045,7 @@ long gui_wps_show(void)
             sb_skin_set_update_delay(0);
             skin_request_full_update(WPS);
             update = true;
-            gwps_enter_wps();
+            gwps_enter_wps(theme_enabled);
         }
         else
         {
@@ -1038,7 +1080,7 @@ long gui_wps_show(void)
 #ifdef AB_REPEAT_ENABLE
             ab_reset_markers();
 #endif
-            gwps_leave_wps();
+            gwps_leave_wps(true);
 #ifdef HAVE_RECORDING
             if (button == ACTION_WPS_REC)
                 return GO_TO_RECSCREEN;
diff --git a/apps/misc.c b/apps/misc.c
index 7da3c57c73..aa79ec632d 100644
--- a/apps/misc.c
+++ b/apps/misc.c
@@ -1579,6 +1579,13 @@ void push_current_activity(enum current_activity screen)
     }
 }
 
+void push_activity_without_refresh(enum current_activity screen)
+{
+    current_activity[current_activity_top++] = screen;
+    FOR_NB_SCREENS(i)
+        skinlist_set_cfg(i, NULL);
+}
+
 void pop_current_activity(enum activity_refresh refresh)
 {
     current_activity_top--;
diff --git a/apps/misc.h b/apps/misc.h
index 4f4527f686..e59399d55b 100644
--- a/apps/misc.h
+++ b/apps/misc.h
@@ -221,6 +221,7 @@ enum activity_refresh
 };
 
 void push_current_activity(enum current_activity screen);
+void push_activity_without_refresh(enum current_activity screen);
 void pop_current_activity(enum activity_refresh refresh);
 enum current_activity get_current_activity(void);
 
diff --git a/apps/playlist_viewer.c b/apps/playlist_viewer.c
index 90a47c35ea..4c57d1a5ce 100644
--- a/apps/playlist_viewer.c
+++ b/apps/playlist_viewer.c
@@ -143,7 +143,7 @@ static void format_line(const struct playlist_entry* track, char* str,
 static bool update_playlist(bool force);
 static enum pv_onplay_result onplay_menu(int index);
 
-static void close_playlist_viewer(void);
+static void close_playlist_viewer(bool pop_activity);
 
 static void playlist_buffer_init(struct playlist_buffer *pb, char *names_buffer,
                                  int names_buffer_size)
@@ -525,11 +525,12 @@ static enum pv_onplay_result show_track_info(const struct playlist_entry *curren
 static enum pv_onplay_result open_with(const struct playlist_entry *current_track)
 {
     char selected_track[MAX_PATH];
-    close_playlist_viewer();
+    close_playlist_viewer(false); /* don't pop activity yet – relevant for plugin_load */
 
     strmemccpy(selected_track, current_track->name, sizeof(selected_track));
 
     int plugin_return = filetype_list_viewers(selected_track);
+    pop_current_activity(ACTIVITY_REFRESH_DEFERRED);
 
     switch (plugin_return)
     {
@@ -547,11 +548,11 @@ static enum pv_onplay_result open_with(const struct playlist_entry *current_trac
 static enum pv_onplay_result open_pictureflow(const struct playlist_entry *current_track)
 {
     char selected_track[MAX_PATH];
-    close_playlist_viewer();
+    close_playlist_viewer(false); /* don't pop activity yet – relevant for plugin_load */
 
     strmemccpy(selected_track, current_track->name, sizeof(selected_track));
-
     int plugin_return = filetype_load_plugin((void *)"pictureflow", selected_track);
+    pop_current_activity(ACTIVITY_REFRESH_DEFERRED);
 
     switch (plugin_return)
     {
@@ -1092,14 +1093,15 @@ enum playlist_viewer_result playlist_viewer_ex(const char* filename,
     }
 
 exit:
-    close_playlist_viewer();
+    close_playlist_viewer(true);
     return ret;
 }
 
-static void close_playlist_viewer(void)
+static void close_playlist_viewer(bool pop_activity)
 {
     talk_shutup();
-    pop_current_activity(ACTIVITY_REFRESH_DEFERRED);
+    if (pop_activity)
+        pop_current_activity(ACTIVITY_REFRESH_DEFERRED);
     if (viewer.playlist)
     {
         if (viewer.initial_selection)
diff --git a/apps/plugin.c b/apps/plugin.c
index 2be6e10308..21dbe47c54 100644
--- a/apps/plugin.c
+++ b/apps/plugin.c
@@ -894,14 +894,16 @@ int plugin_load(const char* plugin, const void* parameter)
     *(p_hdr->api) = &rockbox_api;
     lcd_set_viewport(NULL);
     lcd_clear_display();
-    lcd_update();
 
 #ifdef HAVE_REMOTE_LCD
     lcd_remote_set_viewport(NULL);
     lcd_remote_clear_display();
     lcd_remote_update();
 #endif
-    push_current_activity(ACTIVITY_PLUGIN);
+    if (get_current_activity() == ACTIVITY_WPS)
+        push_activity_without_refresh(ACTIVITY_PLUGIN);
+    else
+        push_current_activity(ACTIVITY_PLUGIN);
     /* some plugins assume the entry cache doesn't move and save pointers to it
      * they should be fixed properly instead of this lock */
     tree_lock_cache(tree_get_context());
@@ -922,7 +924,16 @@ int plugin_load(const char* plugin, const void* parameter)
     int rc = p_hdr->entry_point(parameter);
 
     tree_unlock_cache(tree_get_context());
-    pop_current_activity(ACTIVITY_REFRESH_NOW);
+
+    pop_current_activity(ACTIVITY_REFRESH_DEFERRED);
+    int curr_activity = get_current_activity();
+    if ((curr_activity != ACTIVITY_PLAYLISTVIEWER) &&
+        (curr_activity != ACTIVITY_WPS) &&
+        (rc != PLUGIN_GOTO_WPS))
+    {
+        FOR_NB_SCREENS(i)
+            skin_update(CUSTOM_STATUSBAR, i, SKIN_REFRESH_ALL);
+    }
 
     if (!pfn_tsr_exit)
     {   /* close handle if plugin is no tsr one */
diff --git a/apps/root_menu.c b/apps/root_menu.c
index 3553b794fa..6008c87eda 100644
--- a/apps/root_menu.c
+++ b/apps/root_menu.c
@@ -708,8 +708,11 @@ static inline int load_screen(int screen)
 
     if (activity != ACTIVITY_UNKNOWN)
     {
-        if (ret_val == GO_TO_WPS
-            || ret_val == GO_TO_PREVIOUS_MUSIC)
+        if (ret_val == GO_TO_PLUGIN
+            || ret_val == GO_TO_WPS
+            || ret_val == GO_TO_PREVIOUS_MUSIC
+            || ret_val == GO_TO_PREVIOUS_BROWSER
+            || ret_val == GO_TO_FILEBROWSER)
         {
             pop_current_activity(ACTIVITY_REFRESH_DEFERRED);
         }
@@ -986,7 +989,10 @@ void root_menu(void)
                     }
                 }
 
-                next_screen = load_plugin_screen(key);
+
+                push_activity_without_refresh(ACTIVITY_UNKNOWN); /* prevent plugin_load */
+                next_screen = load_plugin_screen(key);           /* from flashing root  */
+                pop_current_activity(ACTIVITY_REFRESH_DEFERRED); /* menu activity       */
 
                 if (next_screen == GO_TO_PREVIOUS)
                 {