F2 renames the layer if a range of frames is not selected (fix #2326)

In this way we can use F2 to:

1. Set the Loop section if two or more frames are selected
2. Remove the loop section if only one frame is selected
3. Rename the active layer if the layer is selected (or no frames are selected)

data/gui.xml

@@ -76,6 +76,7 @@
       <key command="CanvasSize" shortcut="C" />
       <!-- Layer -->
       <key command="LayerProperties" shortcut="Shift+P" />
+      <key command="LayerProperties" shortcut="F2" context="Normal" />
       <key command="LayerVisibility" shortcut="Shift+X" />
       <key command="OpenGroup" shortcut="Shift+E" />
       <key command="NewLayer" shortcut="Shift+N" />
@@ -147,7 +148,7 @@
       <key command="ShowGrid" shortcut="Ctrl+'" mac="Cmd+'" />
       <key command="ShowPixelGrid" shortcut="Ctrl+Shift+'" mac="Cmd+Shift+'" />
       <key command="SnapToGrid" shortcut="Shift+S" />
-      <key command="SetLoopSection" shortcut="F2" />
+      <key command="SetLoopSection" shortcut="F2" context="FramesSelection" />
       <key command="ShowOnionSkin" shortcut="F3" />
       <key command="ToggleTimelineThumbnails" shortcut="F6" />
       <key command="Timeline" shortcut="Tab">

data/strings/en.ini

@@ -1080,6 +1080,7 @@ key_context_rotating_selection = Rotating Selection
 key_context_move_tool = Move Tool
 key_context_freehand_tool = Freehand Tool
 key_context_shape_tool = Shape Tool
+key_context_frames_selection = Frames Selection
 copy_selection = Copy Selection
 snap_to_grid = Snap To Grid
 lock_axis = Lock Axis

src/app/ui/key_context.h

@@ -1,4 +1,5 @@
 // Aseprite
+// Copyright (C) 2023  Igara Studio S.A.
 // Copyright (C) 2017  David Capello
 //
 // This program is distributed under the terms of
@@ -21,6 +22,7 @@ namespace app {
     FreehandTool,
     ShapeTool,
     MouseWheel,
+    FramesSelection,
   };
 
 } // namespace app

src/app/ui/keyboard_shortcuts.cpp

@@ -1,5 +1,5 @@
 // Aseprite
-// Copyright (C) 2018-2022  Igara Studio S.A.
+// Copyright (C) 2018-2023  Igara Studio S.A.
 // Copyright (C) 2001-2018  David Capello
 //
 // This program is distributed under the terms of
@@ -23,6 +23,7 @@
 #include "app/tools/tool.h"
 #include "app/tools/tool_box.h"
 #include "app/ui/key.h"
+#include "app/ui/timeline/timeline.h"
 #include "app/ui_context.h"
 #include "app/xml_document.h"
 #include "app/xml_exception.h"
@@ -90,6 +91,7 @@ namespace {
     { "MoveTool"             , app::KeyContext::MoveTool },
     { "FreehandTool"         , app::KeyContext::FreehandTool },
     { "ShapeTool"            , app::KeyContext::ShapeTool },
+    { "FramesSelection"      , app::KeyContext::FramesSelection },
     { NULL                   , app::KeyContext::Any }
   };
 
@@ -435,13 +437,15 @@ void Key::add(const ui::Accelerator& accel,
 const ui::Accelerator* Key::isPressed(const Message* msg,
                                       KeyboardShortcuts& globalKeys) const
 {
+  const KeyContext currentKeyContext = globalKeys.getCurrentKeyContext();
+
   if (auto keyMsg = dynamic_cast<const KeyMessage*>(msg)) {
     for (const Accelerator& accel : accels()) {
       if (accel.isPressed(keyMsg->modifiers(),
                           keyMsg->scancode(),
                           keyMsg->unicodeChar()) &&
           (m_keycontext == KeyContext::Any ||
-           m_keycontext == globalKeys.getCurrentKeyContext())) {
+           m_keycontext == currentKeyContext)) {
         return &accel;
       }
     }
@@ -1081,10 +1085,19 @@ KeyContext KeyboardShortcuts::getCurrentKeyContext()
       // eyedropper, but we want to use alt+left and alt+right in the
       // original context (the selection tool).
       App::instance()->activeToolManager()
-        ->selectedTool()->getInk(0)->isSelection())
+        ->selectedTool()->getInk(0)->isSelection()) {
     return KeyContext::SelectionTool;
-  else
-    return KeyContext::Normal;
+  }
+
+  auto timeline = App::instance()->timeline();
+  if (doc && timeline &&
+      !timeline->selectedFrames().empty() &&
+      (timeline->range().type() == DocRange::kFrames ||
+       timeline->range().type() == DocRange::kCels)) {
+    return KeyContext::FramesSelection;
+  }
+
+  return KeyContext::Normal;
 }
 
 bool KeyboardShortcuts::getCommandFromKeyMessage(const Message* msg, Command** command, Params* params)
@@ -1338,6 +1351,8 @@ std::string convertKeyContextToUserFriendlyString(KeyContext keyContext)
       return I18N_KEY(key_context_freehand_tool);
     case KeyContext::ShapeTool:
       return I18N_KEY(key_context_shape_tool);
+    case KeyContext::FramesSelection:
+      return I18N_KEY(key_context_frames_selection);
   }
   return std::string();
 }