Fix scrolling left button inadvertently cancels listtree

Depending on the actual keymap, canceling a listtree with the
"scroll left" button may not be intended, especially
if the list is entered from a completely different focus
(think of leaving a plugin with "long left")

Note:
initializing "scrolling_left" with true without anything actually
scrolling sounds odd to me... maybe this variable should be renamed?
"pgleft_allow_cancel" comes to my mind (with opposite boolean states)

Change-Id: I58a747fc90e91ae96e75932febb462f1f1a1b4ca

1 files changed, 8 insertions, 6 deletions

diff --git a/apps/gui/list.c b/apps/gui/list.c
index 8663abe..eb5f298 100644
--- a/apps/gui/list.c
+++ b/apps/gui/list.c
@@ -625,7 +625,7 @@ bool gui_synclist_do_button(struct gui_synclist * lists,
 {
     int action = *actionptr;
 #ifdef HAVE_LCD_BITMAP
-    static bool scrolling_left = false;
+    static bool pgleft_allow_cancel = false;
 #endif
 
 #ifdef HAVE_WHEEL_ACCELERATION
@@ -735,24 +735,26 @@ bool gui_synclist_do_button(struct gui_synclist * lists,
             to skip to root. ACTION_TREE_ROOT_INIT must be defined in the
             keymaps as a repeated button press (the same as the repeated
             ACTION_TREE_PGLEFT) with the pre condition being the non-repeated
-            button press */
+            button press. Leave out ACTION_TREE_ROOT_INIT in your keymaps to
+            disable cancel action by PGLEFT key (e.g. if PGLEFT and CANCEL
+            are mapped to different keys) */
             if (lists->offset_position[0] == 0)
             {
-                scrolling_left = false;
+                pgleft_allow_cancel = true;
                 *actionptr = ACTION_STD_CANCEL;
                 return true;
             }
             *actionptr = ACTION_TREE_PGLEFT;
         case ACTION_TREE_PGLEFT:
-            if(!scrolling_left && (lists->offset_position[0] == 0))
+            if(pgleft_allow_cancel && (lists->offset_position[0] == 0))
             {
                 *actionptr = ACTION_STD_CANCEL;
                 return false;
             }
             gui_synclist_scroll_left(lists);
             gui_synclist_draw(lists);
-            scrolling_left = true; /* stop ACTION_TREE_PAGE_LEFT
-                                      skipping to root */
+            pgleft_allow_cancel = false; /* stop ACTION_TREE_PAGE_LEFT
+                                            skipping to root */
             return true;
 #endif
 /* for pgup / pgdown, we are obliged to have a different behaviour depending