diff --git a/src/app/widget_loader.cpp b/src/app/widget_loader.cpp
index 00e5c5e22..afcaf5c8f 100644
--- a/src/app/widget_loader.cpp
+++ b/src/app/widget_loader.cpp
@@ -215,7 +215,7 @@ Widget* WidgetLoader::convertXmlElementToWidget(const TiXmlElement* elem, Widget
     text = (text ? TRANSLATE_ATTR(text): NULL);
 
     if (looklike != NULL && strcmp(looklike, "button") == 0) {
-      widget = new CheckBox(text, JI_BUTTON);
+      widget = new CheckBox(text, kButtonWidget);
     }
     else {
       widget = new CheckBox(text);
@@ -324,7 +324,7 @@ Widget* WidgetLoader::convertXmlElementToWidget(const TiXmlElement* elem, Widget
     int radio_group = (group ? ustrtol(group, NULL, 10): 1);
 
     if (looklike != NULL && strcmp(looklike, "button") == 0) {
-      widget = new RadioButton(text, radio_group, JI_BUTTON);
+      widget = new RadioButton(text, radio_group, kButtonWidget);
     }
     else {
       widget = new RadioButton(text, radio_group);
@@ -466,12 +466,12 @@ Widget* WidgetLoader::convertXmlElementToWidget(const TiXmlElement* elem, Widget
       child = convertXmlElementToWidget(childElem, root);
       if (child) {
         // Attach the child in the view
-        if (widget->type == JI_VIEW) {
+        if (widget->type == kViewWidget) {
           static_cast<View*>(widget)->attachToView(child);
           break;
         }
         // Add the child in the grid
-        else if (widget->type == JI_GRID) {
+        else if (widget->type == kGridWidget) {
           const char* cell_hspan = childElem->Attribute("cell_hspan");
           const char* cell_vspan = childElem->Attribute("cell_vspan");
           const char* cell_align = childElem->Attribute("cell_align");
@@ -490,7 +490,7 @@ Widget* WidgetLoader::convertXmlElementToWidget(const TiXmlElement* elem, Widget
       childElem = childElem->NextSiblingElement();
     }
 
-    if (widget->type == JI_VIEW) {
+    if (widget->type == kViewWidget) {
       bool maxsize = bool_attr_is_true(elem, "maxsize");
       if (maxsize)
         static_cast<View*>(widget)->makeVisibleAllScrollableArea();
diff --git a/src/app_menus.cpp b/src/app_menus.cpp
index 402948875..b70581a5e 100644
--- a/src/app_menus.cpp
+++ b/src/app_menus.cpp
@@ -369,7 +369,7 @@ void AppMenus::applyShortcutToMenuitemsWithCommand(Menu* menu, Command *command,
   UI_FOREACH_WIDGET(menu->getChildren(), it) {
     Widget* child = *it;
 
-    if (child->getType() == JI_MENUITEM) {
+    if (child->getType() == kMenuItemWidget) {
       ASSERT(dynamic_cast<MenuItem2*>(child) != NULL);
 
       MenuItem2* menuitem = static_cast<MenuItem2*>(child);
diff --git a/src/commands/cmd_palette_editor.cpp b/src/commands/cmd_palette_editor.cpp
index 7eb41145a..dc2ad5ec1 100644
--- a/src/commands/cmd_palette_editor.cpp
+++ b/src/commands/cmd_palette_editor.cpp
@@ -249,8 +249,8 @@ PaletteEntryEditor::PaletteEntryEditor()
   , m_vbox(JI_VERTICAL)
   , m_topBox(JI_HORIZONTAL)
   , m_bottomBox(JI_HORIZONTAL)
-  , m_rgbButton("RGB", 1, JI_BUTTON)
-  , m_hsvButton("HSB", 1, JI_BUTTON)
+  , m_rgbButton("RGB", 1, kButtonWidget)
+  , m_hsvButton("HSB", 1, kButtonWidget)
   , m_entryLabel("")
   , m_moreOptions("+")
   , m_copyButton("Copy")
diff --git a/src/commands/filters/color_curve_editor.cpp b/src/commands/filters/color_curve_editor.cpp
index 0672692f6..955d8c8c5 100644
--- a/src/commands/filters/color_curve_editor.cpp
+++ b/src/commands/filters/color_curve_editor.cpp
@@ -75,7 +75,7 @@ enum {
 using namespace ui;
 
 ColorCurveEditor::ColorCurveEditor(ColorCurve* curve, int x1, int y1, int x2, int y2)
-  : Widget(JI_WIDGET)
+  : Widget(kGenericWidget)
   , m_curve(curve)
 {
   this->setFocusStop(true);
diff --git a/src/commands/filters/filter_preview.cpp b/src/commands/filters/filter_preview.cpp
index 063327d01..68b82c496 100644
--- a/src/commands/filters/filter_preview.cpp
+++ b/src/commands/filters/filter_preview.cpp
@@ -30,7 +30,7 @@
 using namespace ui;
 
 FilterPreview::FilterPreview(FilterManagerImpl* filterMgr)
-  : Widget(JI_WIDGET)
+  : Widget(kGenericWidget)
   , m_filterMgr(filterMgr)
   , m_timer(1, this)
 {
diff --git a/src/dialogs/aniedit.cpp b/src/dialogs/aniedit.cpp
index d1f041034..ad2c75298 100644
--- a/src/dialogs/aniedit.cpp
+++ b/src/dialogs/aniedit.cpp
@@ -236,7 +236,7 @@ void switch_between_animation_and_sprite_editor(Context* context)
 // The Animation Editor
 
 AnimationEditor::AnimationEditor(Context* context)
-  : Widget(JI_WIDGET)
+  : Widget(kGenericWidget)
   , m_context(context)
 {
   DocumentLocation location = context->getActiveLocation();
diff --git a/src/modules/gui.cpp b/src/modules/gui.cpp
index 8d248127d..a9ba229c7 100644
--- a/src/modules/gui.cpp
+++ b/src/modules/gui.cpp
@@ -451,7 +451,7 @@ void set_gfxicon_to_button(ButtonBase* button,
 
 CheckBox* check_button_new(const char *text, int b1, int b2, int b3, int b4)
 {
-  CheckBox* widget = new CheckBox(text, JI_BUTTON);
+  CheckBox* widget = new CheckBox(text, kButtonWidget);
 
   widget->setAlign(JI_CENTER | JI_MIDDLE);
 
diff --git a/src/skin/skin_theme.cpp b/src/skin/skin_theme.cpp
index 61a7d6ecf..2b1fb828f 100644
--- a/src/skin/skin_theme.cpp
+++ b/src/skin/skin_theme.cpp
@@ -609,12 +609,12 @@ void SkinTheme::initWidget(Widget* widget)
 
   switch (widget->type) {
 
-    case JI_BOX:
+    case kBoxWidget:
       BORDER(0);
       widget->child_spacing = 4 * scale;
       break;
 
-    case JI_BUTTON:
+    case kButtonWidget:
       BORDER4(m_part[PART_BUTTON_NORMAL_W]->w,
               m_part[PART_BUTTON_NORMAL_N]->h,
               m_part[PART_BUTTON_NORMAL_E]->w,
@@ -622,7 +622,7 @@ void SkinTheme::initWidget(Widget* widget)
       widget->child_spacing = 0;
       break;
 
-    case JI_CHECK:
+    case kCheckWidget:
       BORDER(2 * scale);
       widget->child_spacing = 4 * scale;
 
@@ -634,33 +634,33 @@ void SkinTheme::initWidget(Widget* widget)
                             JI_LEFT | JI_MIDDLE));
       break;
 
-    case JI_ENTRY:
+    case kEntryWidget:
       BORDER4(m_part[PART_SUNKEN_NORMAL_W]->w,
               m_part[PART_SUNKEN_NORMAL_N]->h,
               m_part[PART_SUNKEN_NORMAL_E]->w,
               m_part[PART_SUNKEN_NORMAL_S]->h);
       break;
 
-    case JI_GRID:
+    case kGridWidget:
       BORDER(0);
       widget->child_spacing = 4 * scale;
       break;
 
-    case JI_LABEL:
+    case kLabelWidget:
       BORDER(1 * scale);
       static_cast<Label*>(widget)->setTextColor(getColor(ThemeColor::Text));
       break;
 
-    case JI_LISTBOX:
+    case kListBoxWidget:
       BORDER(0);
       widget->child_spacing = 0;
       break;
 
-    case JI_LISTITEM:
+    case kListItemWidget:
       BORDER(1 * scale);
       break;
 
-    case JI_COMBOBOX:
+    case kComboBoxWidget:
       {
         ComboBox* combobox = dynamic_cast<ComboBox*>(widget);
         ASSERT(combobox != NULL);
@@ -684,24 +684,24 @@ void SkinTheme::initWidget(Widget* widget)
       }
       break;
 
-    case JI_MENU:
-    case JI_MENUBAR:
-    case JI_MENUBOX:
+    case kMenuWidget:
+    case kMenuBarWidget:
+    case kMenuBoxWidget:
       BORDER(0);
       widget->child_spacing = 0;
       break;
 
-    case JI_MENUITEM:
+    case kMenuItemWidget:
       BORDER(2 * scale);
       widget->child_spacing = 18 * scale;
       break;
 
-    case JI_SPLITTER:
+    case kSplitterWidget:
       BORDER(0);
       widget->child_spacing = 3 * scale;
       break;
 
-    case JI_RADIO:
+    case kRadioWidget:
       BORDER(2 * scale);
       widget->child_spacing = 4 * scale;
 
@@ -713,7 +713,7 @@ void SkinTheme::initWidget(Widget* widget)
                             JI_LEFT | JI_MIDDLE));
       break;
 
-    case JI_SEPARATOR:
+    case kSeparatorWidget:
       /* frame */
       if ((widget->getAlign() & JI_HORIZONTAL) &&
           (widget->getAlign() & JI_VERTICAL)) {
@@ -736,7 +736,7 @@ void SkinTheme::initWidget(Widget* widget)
       }
       break;
 
-    case JI_SLIDER:
+    case kSliderWidget:
       BORDER4(m_part[PART_SLIDER_EMPTY_W]->w-1*scale,
               m_part[PART_SLIDER_EMPTY_N]->h,
               m_part[PART_SLIDER_EMPTY_E]->w-1*scale,
@@ -745,12 +745,12 @@ void SkinTheme::initWidget(Widget* widget)
       widget->setAlign(JI_CENTER | JI_MIDDLE);
       break;
 
-    case JI_TEXTBOX:
+    case kTextBoxWidget:
       BORDER(0);
       widget->child_spacing = 0;
       break;
 
-    case JI_VIEW:
+    case kViewWidget:
       BORDER4(m_part[PART_SUNKEN_NORMAL_W]->w-1*scale,
               m_part[PART_SUNKEN_NORMAL_N]->h,
               m_part[PART_SUNKEN_NORMAL_E]->w-1*scale,
@@ -758,17 +758,17 @@ void SkinTheme::initWidget(Widget* widget)
       widget->child_spacing = 0;
       break;
 
-    case JI_VIEW_SCROLLBAR:
+    case kViewScrollbarWidget:
       BORDER(1 * scale);
       widget->child_spacing = 0;
       break;
 
-    case JI_VIEW_VIEWPORT:
+    case kViewViewportWidget:
       BORDER(0);
       widget->child_spacing = 0;
       break;
 
-    case JI_WINDOW:
+    case kWindowWidget:
       if (!static_cast<Window*>(widget)->isDesktop()) {
         if (widget->hasText()) {
           BORDER4(6 * scale, (4+6) * scale, 6 * scale, 6 * scale);
@@ -1166,7 +1166,7 @@ void SkinTheme::draw_menuitem(MenuItem* widget, JRect clip)
   if (!widget->getParent()->getParent())
     return;
 
-  bar = (widget->getParent()->getParent()->type == JI_MENUBAR);
+  bar = (widget->getParent()->getParent()->type == kMenuBarWidget);
 
   // Colors
   if (!widget->isEnabled()) {
diff --git a/src/ui/base.h b/src/ui/base.h
index ecb61cef2..f6ceac706 100644
--- a/src/ui/base.h
+++ b/src/ui/base.h
@@ -60,41 +60,6 @@ namespace ui {
 #define JI_NOTEXT       0x0800 // The widget does not have text.
 #define JI_DIRTY        0x1000 // The widget (or one child) is dirty (update_region != empty).
 
-  // Widget types.
-  enum {
-    // Undefined (or anonymous) widget type.
-    JI_WIDGET,
-
-    // Known widgets.
-    JI_BOX,
-    JI_BUTTON,
-    JI_CHECK,
-    JI_COMBOBOX,
-    JI_ENTRY,
-    JI_GRID,
-    JI_IMAGE_VIEW,
-    JI_LABEL,
-    JI_LISTBOX,
-    JI_LISTITEM,
-    JI_MANAGER,
-    JI_MENU,
-    JI_MENUBAR,
-    JI_MENUBOX,
-    JI_MENUITEM,
-    JI_SPLITTER,
-    JI_RADIO,
-    JI_SEPARATOR,
-    JI_SLIDER,
-    JI_TEXTBOX,
-    JI_VIEW,
-    JI_VIEW_SCROLLBAR,
-    JI_VIEW_VIEWPORT,
-    JI_WINDOW,
-
-    // User widgets.
-    JI_USER_WIDGET,
-  };
-
   // JINETE Message types.
   enum {
     // General messages.
diff --git a/src/ui/box.cpp b/src/ui/box.cpp
index b5ee24e84..c37cffe5a 100644
--- a/src/ui/box.cpp
+++ b/src/ui/box.cpp
@@ -20,7 +20,7 @@ using namespace gfx;
 namespace ui {
 
 Box::Box(int align)
-  : Widget(JI_BOX)
+  : Widget(kBoxWidget)
 {
   setAlign(align);
   initTheme();
diff --git a/src/ui/button.cpp b/src/ui/button.cpp
index 9d717022e..e4dae0fd0 100644
--- a/src/ui/button.cpp
+++ b/src/ui/button.cpp
@@ -23,7 +23,10 @@
 
 namespace ui {
 
-ButtonBase::ButtonBase(const char* text, int type, int behaviorType, int drawType)
+ButtonBase::ButtonBase(const char* text,
+                       WidgetType type,
+                       WidgetType behaviorType,
+                       WidgetType drawType)
   : Widget(type)
   , m_pressedStatus(false)
   , m_handleSelect(true)
@@ -47,12 +50,12 @@ ButtonBase::~ButtonBase()
     m_iconInterface->destroy();
 }
 
-int ButtonBase::getBehaviorType() const
+WidgetType ButtonBase::getBehaviorType() const
 {
   return m_behaviorType;
 }
 
-int ButtonBase::getDrawType() const
+WidgetType ButtonBase::getDrawType() const
 {
   return m_drawType;
 }
@@ -80,7 +83,7 @@ bool ButtonBase::onProcessMessage(Message* msg)
     case JM_FOCUSENTER:
     case JM_FOCUSLEAVE:
       if (isEnabled()) {
-        if (m_behaviorType == JI_BUTTON) {
+        if (m_behaviorType == kButtonWidget) {
           // Deselect the widget (maybe the user press the key, but
           // before release it, changes the focus).
           if (isSelected())
@@ -95,8 +98,8 @@ bool ButtonBase::onProcessMessage(Message* msg)
     case JM_KEYPRESSED:
       // If the button is enabled.
       if (isEnabled()) {
-        // For JI_BUTTON
-        if (m_behaviorType == JI_BUTTON) {
+        // For kButtonWidget
+        if (m_behaviorType == kButtonWidget) {
           // Has focus and press enter/space
           if (hasFocus()) {
             if ((msg->key.scancode == KEY_ENTER) ||
@@ -126,7 +129,7 @@ bool ButtonBase::onProcessMessage(Message* msg)
             return true;
           }
         }
-        // For JI_CHECK or JI_RADIO
+        // For kCheckWidget or kRadioWidget
         else {
           /* if the widget has the focus and the user press space or
              if the user press Alt+the underscored letter of the button */
@@ -134,13 +137,13 @@ bool ButtonBase::onProcessMessage(Message* msg)
                (msg->key.scancode == KEY_SPACE)) ||
               ((msg->any.shifts & KB_ALT_FLAG) &&
                (isScancodeMnemonic(msg->key.scancode)))) {
-            if (m_behaviorType == JI_CHECK) {
+            if (m_behaviorType == kCheckWidget) {
               // Swap the select status
               setSelected(!isSelected());
 
               invalidate();
             }
-            else if (m_behaviorType == JI_RADIO) {
+            else if (m_behaviorType == kRadioWidget) {
               if (!isSelected()) {
                 setSelected(true);
               }
@@ -153,7 +156,7 @@ bool ButtonBase::onProcessMessage(Message* msg)
 
     case JM_KEYRELEASED:
       if (isEnabled()) {
-        if (m_behaviorType == JI_BUTTON) {
+        if (m_behaviorType == kButtonWidget) {
           if (isSelected()) {
             generateButtonSelectSignal();
             return true;
@@ -165,7 +168,7 @@ bool ButtonBase::onProcessMessage(Message* msg)
     case JM_BUTTONPRESSED:
       switch (m_behaviorType) {
 
-        case JI_BUTTON:
+        case kButtonWidget:
           if (isEnabled()) {
             setSelected(true);
 
@@ -174,7 +177,7 @@ bool ButtonBase::onProcessMessage(Message* msg)
           }
           return true;
 
-        case JI_CHECK:
+        case kCheckWidget:
           if (isEnabled()) {
             setSelected(!isSelected());
 
@@ -183,7 +186,7 @@ bool ButtonBase::onProcessMessage(Message* msg)
           }
           return true;
 
-        case JI_RADIO:
+        case kRadioWidget:
           if (isEnabled()) {
             if (!isSelected()) {
               m_handleSelect = false;
@@ -205,11 +208,11 @@ bool ButtonBase::onProcessMessage(Message* msg)
         if (hasMouseOver()) {
           switch (m_behaviorType) {
 
-            case JI_BUTTON:
+            case kButtonWidget:
               generateButtonSelectSignal();
               break;
 
-            case JI_CHECK:
+            case kCheckWidget:
               {
                 // Fire onClick() event
                 Event ev(this);
@@ -219,7 +222,7 @@ bool ButtonBase::onProcessMessage(Message* msg)
               }
               break;
 
-            case JI_RADIO:
+            case kRadioWidget:
               {
                 setSelected(false);
                 setSelected(true);
@@ -281,9 +284,9 @@ void ButtonBase::onPreferredSize(PreferredSizeEvent& ev)
 void ButtonBase::onPaint(PaintEvent& ev)
 {
   switch (m_drawType) {
-    case JI_BUTTON: getTheme()->paintButton(ev); break;
-    case JI_CHECK:  getTheme()->paintCheckBox(ev); break;
-    case JI_RADIO:  getTheme()->paintRadioButton(ev); break;
+    case kButtonWidget: getTheme()->paintButton(ev); break;
+    case kCheckWidget:  getTheme()->paintCheckBox(ev); break;
+    case kRadioWidget:  getTheme()->paintRadioButton(ev); break;
   }
 }
 
@@ -302,7 +305,7 @@ void ButtonBase::generateButtonSelectSignal()
 // ======================================================================
 
 Button::Button(const char *text)
-  : ButtonBase(text, JI_BUTTON, JI_BUTTON, JI_BUTTON)
+  : ButtonBase(text, kButtonWidget, kButtonWidget, kButtonWidget)
 {
   setAlign(JI_CENTER | JI_MIDDLE);
 }
@@ -311,8 +314,8 @@ Button::Button(const char *text)
 // CheckBox class
 // ======================================================================
 
-CheckBox::CheckBox(const char *text, int drawType)
-  : ButtonBase(text, JI_CHECK, JI_CHECK, drawType)
+CheckBox::CheckBox(const char *text, WidgetType drawType)
+  : ButtonBase(text, kCheckWidget, kCheckWidget, drawType)
 {
   setAlign(JI_LEFT | JI_MIDDLE);
 }
@@ -321,8 +324,8 @@ CheckBox::CheckBox(const char *text, int drawType)
 // RadioButton class
 // ======================================================================
 
-RadioButton::RadioButton(const char *text, int radioGroup, int drawType)
-  : ButtonBase(text, JI_RADIO, JI_RADIO, drawType)
+RadioButton::RadioButton(const char *text, int radioGroup, WidgetType drawType)
+  : ButtonBase(text, kRadioWidget, kRadioWidget, drawType)
 {
   setAlign(JI_LEFT | JI_MIDDLE);
   setRadioGroup(radioGroup);
@@ -371,7 +374,7 @@ void RadioButton::onSelect()
   if (!m_handleSelect)
     return;
 
-  if (getBehaviorType() == JI_RADIO) {
+  if (getBehaviorType() == kRadioWidget) {
     deselectRadioGroup();
 
     m_handleSelect = false;
diff --git a/src/ui/button.h b/src/ui/button.h
index 8f43cc07a..fca340b1a 100644
--- a/src/ui/button.h
+++ b/src/ui/button.h
@@ -37,13 +37,13 @@ namespace ui {
   {
   public:
     ButtonBase(const char* text,
-               int type,
-               int behaviorType,
-               int drawType);
+               WidgetType type,
+               WidgetType behaviorType,
+               WidgetType drawType);
     virtual ~ButtonBase();
 
-    int getBehaviorType() const;
-    int getDrawType() const;
+    WidgetType getBehaviorType() const;
+    WidgetType getDrawType() const;
 
     // Sets the interface used to get icons for the button depending its
     // state. This interface is deleted automatically in the ButtonBase dtor.
@@ -68,8 +68,8 @@ namespace ui {
     void generateButtonSelectSignal();
 
     bool m_pressedStatus;
-    int m_behaviorType;
-    int m_drawType;
+    WidgetType m_behaviorType;
+    WidgetType m_drawType;
     IButtonIcon* m_iconInterface;
 
   protected:
@@ -87,14 +87,14 @@ namespace ui {
   class CheckBox : public ButtonBase
   {
   public:
-    CheckBox(const char* text, int drawType = JI_CHECK);
+    CheckBox(const char* text, WidgetType drawType = kCheckWidget);
   };
 
   // Radio buttons
   class RadioButton : public ButtonBase
   {
   public:
-    RadioButton(const char* text, int radioGroup, int drawType = JI_RADIO);
+    RadioButton(const char* text, int radioGroup, WidgetType drawType = kRadioWidget);
 
     int getRadioGroup() const;
     void setRadioGroup(int radioGroup);
diff --git a/src/ui/combobox.cpp b/src/ui/combobox.cpp
index 935089fa5..5005cd4af 100644
--- a/src/ui/combobox.cpp
+++ b/src/ui/combobox.cpp
@@ -78,7 +78,7 @@ private:
 };
 
 ComboBox::ComboBox()
-  : Widget(JI_COMBOBOX)
+  : Widget(kComboBoxWidget)
 {
   m_entry = new ComboBoxEntry(this);
   m_button = new ComboBoxButton();
diff --git a/src/ui/entry.cpp b/src/ui/entry.cpp
index 541946a93..8dacbb9b3 100644
--- a/src/ui/entry.cpp
+++ b/src/ui/entry.cpp
@@ -28,7 +28,7 @@
 namespace ui {
 
 Entry::Entry(size_t maxsize, const char *format, ...)
-  : Widget(JI_ENTRY)
+  : Widget(kEntryWidget)
   , m_timer(500, this)
 {
   char buf[4096];
diff --git a/src/ui/grid.cpp b/src/ui/grid.cpp
index 2f2b69474..2b24a579c 100644
--- a/src/ui/grid.cpp
+++ b/src/ui/grid.cpp
@@ -35,7 +35,7 @@ Grid::Cell::Cell()
 }
 
 Grid::Grid(int columns, bool same_width_columns)
-  : Widget(JI_GRID)
+  : Widget(kGridWidget)
   , m_colstrip(columns)
 {
   ASSERT(columns > 0);
diff --git a/src/ui/grid_ui_unittest.cpp b/src/ui/grid_ui_unittest.cpp
index 3509a9f71..7ad30032f 100644
--- a/src/ui/grid_ui_unittest.cpp
+++ b/src/ui/grid_ui_unittest.cpp
@@ -27,8 +27,8 @@ using namespace ui;
 TEST(JGrid, Simple2x1Grid)
 {
   Grid* grid = new Grid(2, false);
-  Widget* w1 = new Widget(JI_WIDGET);
-  Widget* w2 = new Widget(JI_WIDGET);
+  Widget* w1 = new Widget(kGenericWidget);
+  Widget* w2 = new Widget(kGenericWidget);
 
   jwidget_set_min_size(w1, 10, 10);
   jwidget_set_min_size(w2, 10, 10);
@@ -66,8 +66,8 @@ TEST(JGrid, Simple2x1Grid)
 TEST(JGrid, Expand2ndWidget)
 {
   Grid* grid = new Grid(2, false);
-  Widget* w1 = new Widget(JI_WIDGET);
-  Widget* w2 = new Widget(JI_WIDGET);
+  Widget* w1 = new Widget(kGenericWidget);
+  Widget* w2 = new Widget(kGenericWidget);
   JRect rect;
 
   jwidget_set_min_size(w1, 20, 20);
@@ -102,8 +102,8 @@ TEST(JGrid, Expand2ndWidget)
 TEST(JGrid, SameWidth2x1Grid)
 {
   Grid* grid = new Grid(2, true);
-  Widget* w1 = new Widget(JI_WIDGET);
-  Widget* w2 = new Widget(JI_WIDGET);
+  Widget* w1 = new Widget(kGenericWidget);
+  Widget* w2 = new Widget(kGenericWidget);
   JRect rect;
 
   jwidget_set_min_size(w1, 20, 20);
@@ -167,10 +167,10 @@ TEST(JGrid, SameWidth2x1Grid)
 TEST(JGrid, Intrincate3x3Grid)
 {
   Grid* grid = new Grid(3, false);
-  Widget* w1 = new Widget(JI_WIDGET);
-  Widget* w2 = new Widget(JI_WIDGET);
-  Widget* w3 = new Widget(JI_WIDGET);
-  Widget* w4 = new Widget(JI_WIDGET);
+  Widget* w1 = new Widget(kGenericWidget);
+  Widget* w2 = new Widget(kGenericWidget);
+  Widget* w3 = new Widget(kGenericWidget);
+  Widget* w4 = new Widget(kGenericWidget);
   JRect rect;
 
   jwidget_set_min_size(w1, 10, 10);
diff --git a/src/ui/gui.h b/src/ui/gui.h
index 1812e0431..bb9b56546 100644
--- a/src/ui/gui.h
+++ b/src/ui/gui.h
@@ -58,6 +58,7 @@
 #include "ui/view.h"
 #include "ui/viewport.h"
 #include "ui/widget.h"
+#include "ui/widget_type.h"
 #include "ui/widgets_list.h"
 #include "ui/window.h"
 
diff --git a/src/ui/image_view.cpp b/src/ui/image_view.cpp
index 73d3a8c9a..68697b847 100644
--- a/src/ui/image_view.cpp
+++ b/src/ui/image_view.cpp
@@ -20,7 +20,7 @@
 namespace ui {
 
 ImageView::ImageView(BITMAP* bmp, int align)
- : Widget(JI_IMAGE_VIEW)
+ : Widget(kImageViewWidget)
 {
   setAlign(align);
 }
diff --git a/src/ui/intern.cpp b/src/ui/intern.cpp
index c6509ba1b..609ead773 100644
--- a/src/ui/intern.cpp
+++ b/src/ui/intern.cpp
@@ -62,7 +62,7 @@ void reinitThemeForAllWidgets()
   // Remap the windows
   for (std::list<Widget*>::iterator it=widgets->begin(), end=widgets->end();
        it != end; ++it) {
-    if ((*it)->type == JI_WINDOW)
+    if ((*it)->type == kWindowWidget)
       static_cast<Window*>(*it)->remapWindow();
   }
 
diff --git a/src/ui/label.cpp b/src/ui/label.cpp
index 85bb1b9a8..0bb9c3f2a 100644
--- a/src/ui/label.cpp
+++ b/src/ui/label.cpp
@@ -14,7 +14,7 @@
 namespace ui {
 
 Label::Label(const char *text)
-  : Widget(JI_LABEL)
+  : Widget(kLabelWidget)
 {
   setAlign(JI_LEFT | JI_MIDDLE);
   setText(text);
diff --git a/src/ui/listbox.cpp b/src/ui/listbox.cpp
index a788a5548..1bfacf264 100644
--- a/src/ui/listbox.cpp
+++ b/src/ui/listbox.cpp
@@ -22,7 +22,7 @@ using namespace gfx;
 namespace ui {
 
 ListBox::ListBox()
-  : Widget(JI_LISTBOX)
+  : Widget(kListBoxWidget)
 {
   setFocusStop(true);
   initTheme();
diff --git a/src/ui/listitem.cpp b/src/ui/listitem.cpp
index f6e59b2e8..328a121aa 100644
--- a/src/ui/listitem.cpp
+++ b/src/ui/listitem.cpp
@@ -18,7 +18,7 @@ using namespace gfx;
 namespace ui {
 
 ListItem::ListItem(const char* text)
-  : Widget(JI_LISTITEM)
+  : Widget(kListItemWidget)
 {
   setAlign(JI_LEFT | JI_MIDDLE);
   setText(text);
diff --git a/src/ui/manager.cpp b/src/ui/manager.cpp
index 0fa7460f9..f82dbd68f 100644
--- a/src/ui/manager.cpp
+++ b/src/ui/manager.cpp
@@ -109,7 +109,7 @@ Manager* Manager::getDefault()
 }
 
 Manager::Manager()
-  : Widget(JI_MANAGER)
+  : Widget(kManagerWidget)
 {
   if (!m_defaultManager) {
     // Hook the window close message
@@ -1399,7 +1399,7 @@ static Widget* next_widget(Widget* widget)
   if (!widget->getChildren().empty())
     return UI_FIRST_WIDGET(widget->getChildren());
 
-  while (widget->getParent()->type != JI_MANAGER) {
+  while (widget->getParent()->type != kManagerWidget) {
     WidgetsList::const_iterator begin = widget->getParent()->getChildren().begin();
     WidgetsList::const_iterator end = widget->getParent()->getChildren().end();
     WidgetsList::const_iterator it = std::find(begin, end, widget);
diff --git a/src/ui/menu.cpp b/src/ui/menu.cpp
index d29d6233a..ff4fdc34e 100644
--- a/src/ui/menu.cpp
+++ b/src/ui/menu.cpp
@@ -110,7 +110,7 @@ static MenuItem* find_nextitem(Menu* menu, MenuItem* menuitem);
 static MenuItem* find_previtem(Menu* menu, MenuItem* menuitem);
 
 Menu::Menu()
-  : Widget(JI_MENU)
+  : Widget(kMenuWidget)
   , m_menuitem(NULL)
 {
   initTheme();
@@ -128,7 +128,7 @@ Menu::~Menu()
   }
 }
 
-MenuBox::MenuBox(int type)
+MenuBox::MenuBox(WidgetType type)
  : Widget(type)
  , m_base(NULL)
 {
@@ -147,13 +147,13 @@ MenuBox::~MenuBox()
 }
 
 MenuBar::MenuBar()
-  : MenuBox(JI_MENUBAR)
+  : MenuBox(kMenuBarWidget)
 {
   createBase();
 }
 
 MenuItem::MenuItem(const char *text)
-  : Widget(JI_MENUITEM)
+  : Widget(kMenuItemWidget)
 {
   m_accel = NULL;
   m_highlighted = false;
@@ -320,7 +320,7 @@ void Menu::onPreferredSize(PreferredSizeEvent& ev)
   UI_FOREACH_WIDGET_WITH_END(getChildren(), it, end) {
     reqSize = (*it)->getPreferredSize();
 
-    if (this->getParent()->type == JI_MENUBAR) {
+    if (this->getParent()->type == kMenuBarWidget) {
       size.w += reqSize.w + ((it+1 != end) ? this->child_spacing: 0);
       size.h = MAX(size.h, reqSize.h);
     }
@@ -350,14 +350,14 @@ void Menu::set_position(JRect rect)
 
     reqSize = child->getPreferredSize();
 
-    if (this->getParent()->type == JI_MENUBAR)
+    if (this->getParent()->type == kMenuBarWidget)
       cpos->x2 = cpos->x1+reqSize.w;
     else
       cpos->y2 = cpos->y1+reqSize.h;
 
     jwidget_set_rect(child, cpos);
 
-    if (this->getParent()->type == JI_MENUBAR)
+    if (this->getParent()->type == kMenuBarWidget)
       cpos->x1 += jrect_w(cpos);
     else
       cpos->y1 += jrect_h(cpos);
@@ -400,9 +400,9 @@ bool MenuBox::onProcessMessage(Message* msg)
           if (picked == NULL ||         // If the button was clicked nowhere
               picked == this ||         // If the button was clicked in this menubox
               // The picked widget isn't menu-related
-              (picked->type != JI_MENUBOX &&
-               picked->type != JI_MENUBAR &&
-               picked->type != JI_MENUITEM) ||
+              (picked->type != kMenuBoxWidget &&
+               picked->type != kMenuBarWidget &&
+               picked->type != kMenuItemWidget) ||
               // The picked widget (that is menu-related) isn't from
               // the same tree of menus
               (get_base_menubox(picked) != this)) {
@@ -416,7 +416,7 @@ bool MenuBox::onProcessMessage(Message* msg)
         // Get the widget below the mouse cursor
         Widget* picked = menu->pick(msg->mouse.x, msg->mouse.y);
         if (picked) {
-          if ((picked->type == JI_MENUITEM) &&
+          if ((picked->type == kMenuItemWidget) &&
               !(picked->flags & JI_DISABLED)) {
 
             // If the picked menu-item is not highlighted...
@@ -424,7 +424,7 @@ bool MenuBox::onProcessMessage(Message* msg)
               // In menu-bar always open the submenu, in other popup-menus
               // open the submenu only if the user does click
               bool open_submenu =
-                (this->type == JI_MENUBAR) ||
+                (this->type == kMenuBarWidget) ||
                 (msg->type == JM_BUTTONPRESSED);
 
               menu->highlightItem(static_cast<MenuItem*>(picked), false, open_submenu, false);
@@ -485,9 +485,9 @@ bool MenuBox::onProcessMessage(Message* msg)
         get_base(this)->was_clicked = false;
 
         // Check for ALT+some underlined letter
-        if (((this->type == JI_MENUBOX) && (msg->any.shifts == 0 || // Inside menu-boxes we can use letters without Alt modifier pressed
-                                            msg->any.shifts == KB_ALT_FLAG)) ||
-            ((this->type == JI_MENUBAR) && (msg->any.shifts == KB_ALT_FLAG))) {
+        if (((this->type == kMenuBoxWidget) && (msg->any.shifts == 0 || // Inside menu-boxes we can use letters without Alt modifier pressed
+                                                msg->any.shifts == KB_ALT_FLAG)) ||
+            ((this->type == kMenuBarWidget) && (msg->any.shifts == KB_ALT_FLAG))) {
           selected = check_for_letter(menu, scancode_to_ascii(msg->key.scancode));
           if (selected) {
             menu->highlightItem(selected, true, true, true);
@@ -504,7 +504,7 @@ bool MenuBox::onProcessMessage(Message* msg)
           // Search a child with highlight or the submenu opened
           UI_FOREACH_WIDGET(menu->getChildren(), it) {
             Widget* child = *it;
-            if (child->type != JI_MENUITEM)
+            if (child->type != kMenuItemWidget)
               continue;
 
             if (static_cast<MenuItem*>(child)->hasSubmenuOpened())
@@ -518,7 +518,7 @@ bool MenuBox::onProcessMessage(Message* msg)
 
             case KEY_ESC:
               // In menu-bar
-              if (this->type == JI_MENUBAR) {
+              if (this->type == kMenuBarWidget) {
                 if (highlight) {
                   cancelMenuLoop();
                   used = true;
@@ -541,7 +541,7 @@ bool MenuBox::onProcessMessage(Message* msg)
 
             case KEY_UP:
               // In menu-bar
-              if (this->type == JI_MENUBAR) {
+              if (this->type == kMenuBarWidget) {
                 if (child_with_submenu_opened)
                   child_with_submenu_opened->closeSubmenu(true);
               }
@@ -556,7 +556,7 @@ bool MenuBox::onProcessMessage(Message* msg)
 
             case KEY_DOWN:
               // In menu-bar
-              if (this->type == JI_MENUBAR) {
+              if (this->type == kMenuBarWidget) {
                 // Select the active menu
                 menu->highlightItem(highlight, true, true, true);
               }
@@ -571,7 +571,7 @@ bool MenuBox::onProcessMessage(Message* msg)
 
             case KEY_LEFT:
               // In menu-bar
-              if (this->type == JI_MENUBAR) {
+              if (this->type == kMenuBarWidget) {
                 // Go to previous
                 highlight = find_previtem(menu, highlight);
                 menu->highlightItem(highlight, false, false, false);
@@ -585,7 +585,7 @@ bool MenuBox::onProcessMessage(Message* msg)
                   // Go to the previous item in the parent
 
                   // If the parent is the menu-bar
-                  if (parent->type == JI_MENUBAR) {
+                  if (parent->type == kMenuBarWidget) {
                     menu = static_cast<MenuBar*>(parent)->getMenu();
                     MenuItem* menuitem = find_previtem(menu, menu->getHighlightedItem());
 
@@ -604,7 +604,7 @@ bool MenuBox::onProcessMessage(Message* msg)
 
             case KEY_RIGHT:
               // In menu-bar
-              if (this->type == JI_MENUBAR) {
+              if (this->type == kMenuBarWidget) {
                 // Go to next
                 highlight = find_nextitem(menu, highlight);
                 menu->highlightItem(highlight, false, false, false);
@@ -733,7 +733,7 @@ bool MenuItem::onProcessMessage(Message* msg)
         // Menubox position
         pos = jwidget_get_rect(window);
 
-        if (this->getParent()->getParent()->type == JI_MENUBAR) {
+        if (this->getParent()->getParent()->type == kMenuBarWidget) {
           jrect_moveto(pos,
                        MID(0, this->rc->x1, JI_SCREEN_W-jrect_w(pos)),
                        MID(0, this->rc->y2, JI_SCREEN_H-jrect_h(pos)));
@@ -785,7 +785,7 @@ bool MenuItem::onProcessMessage(Message* msg)
           UI_FOREACH_WIDGET(m_submenu->getChildren(), it) {
             Widget* child = *it;
 
-            if (child->type != JI_MENUITEM)
+            if (child->type != kMenuItemWidget)
               continue;
 
             if (child->isEnabled()) {
@@ -824,7 +824,7 @@ bool MenuItem::onProcessMessage(Message* msg)
         ASSERT(menubox != NULL);
 
         window = (Window*)menubox->getParent();
-        ASSERT(window && window->type == JI_WINDOW);
+        ASSERT(window && window->type == kWindowWidget);
 
         // Fetch the "menu" to avoid destroy it with 'delete'.
         menubox->setMenu(NULL);
@@ -886,7 +886,7 @@ void MenuItem::onClick()
 void MenuItem::onPreferredSize(PreferredSizeEvent& ev)
 {
   Size size(0, 0);
-  int bar = (this->getParent()->getParent()->type == JI_MENUBAR);
+  int bar = (this->getParent()->getParent()->type == kMenuBarWidget);
 
   if (this->hasText()) {
     size.w =
@@ -915,7 +915,7 @@ static MenuBox* get_base_menubox(Widget* widget)
     ASSERT_VALID_WIDGET(widget);
 
     // We are in a menubox
-    if (widget->type == JI_MENUBOX || widget->type == JI_MENUBAR) {
+    if (widget->type == kMenuBoxWidget || widget->type == kMenuBarWidget) {
       if (static_cast<MenuBox*>(widget)->getBase()) {
         return static_cast<MenuBox*>(widget);
       }
@@ -930,9 +930,9 @@ static MenuBox* get_base_menubox(Widget* widget)
     }
     // We are in a menuitem
     else {
-      ASSERT(widget->type == JI_MENUITEM);
+      ASSERT(widget->type == kMenuItemWidget);
       ASSERT(widget->getParent() != NULL);
-      ASSERT(widget->getParent()->type == JI_MENU);
+      ASSERT(widget->getParent()->type == kMenuWidget);
 
       widget = widget->getParent()->getParent();
     }
@@ -952,7 +952,7 @@ MenuItem* Menu::getHighlightedItem()
 {
   UI_FOREACH_WIDGET(getChildren(), it) {
     Widget* child = *it;
-    if (child->type != JI_MENUITEM)
+    if (child->type != kMenuItemWidget)
       continue;
 
     MenuItem* menuitem = static_cast<MenuItem*>(child);
@@ -967,7 +967,7 @@ void Menu::highlightItem(MenuItem* menuitem, bool click, bool open_submenu, bool
   // Find the menuitem with the highlight
   UI_FOREACH_WIDGET(getChildren(), it) {
     Widget* child = *it;
-    if (child->type != JI_MENUITEM)
+    if (child->type != kMenuItemWidget)
       continue;
 
     if (child != menuitem) {
@@ -1033,7 +1033,7 @@ void MenuItem::openSubmenu(bool select_first)
   if (menu->getParent()) {
     UI_FOREACH_WIDGET(menu->getChildren(), it) {
       Widget* child = *it;
-      if (child->type != JI_MENUITEM)
+      if (child->type != kMenuItemWidget)
         continue;
 
       MenuItem* childMenuItem = static_cast<MenuItem*>(child);
@@ -1081,7 +1081,7 @@ void MenuItem::closeSubmenu(bool last_of_close_chain)
 
   UI_FOREACH_WIDGET(menu->getChildren(), it) {
     Widget* child = *it;
-    if (child->type != JI_MENUITEM)
+    if (child->type != kMenuItemWidget)
       continue;
 
     if (static_cast<MenuItem*>(child)->hasSubmenuOpened())
@@ -1149,7 +1149,7 @@ void Menu::closeAll()
   else {
     UI_FOREACH_WIDGET(menu->getChildren(), it) {
       Widget* child = *it;
-      if (child->type != JI_MENUITEM)
+      if (child->type != kMenuItemWidget)
         continue;
 
       menuitem = static_cast<MenuItem*>(child);
@@ -1159,7 +1159,7 @@ void Menu::closeAll()
   }
 
   // For popuped menus
-  if (base_menubox->type == JI_MENUBOX)
+  if (base_menubox->type == kMenuBoxWidget)
     base_menubox->closePopup();
 }
 
@@ -1198,7 +1198,7 @@ static MenuItem* check_for_letter(Menu* menu, int ascii)
 {
   UI_FOREACH_WIDGET(menu->getChildren(), it) {
     Widget* child = *it;
-    if (child->type != JI_MENUITEM)
+    if (child->type != kMenuItemWidget)
       continue;
 
     MenuItem* menuitem = static_cast<MenuItem*>(child);
@@ -1213,7 +1213,7 @@ static MenuItem* check_for_accel(Menu* menu, Message* msg)
 {
   UI_FOREACH_WIDGET(menu->getChildren(), it) {
     Widget* child = *it;
-    if (child->type != JI_MENUITEM)
+    if (child->type != kMenuItemWidget)
       continue;
 
     MenuItem* menuitem = static_cast<MenuItem*>(child);
@@ -1250,7 +1250,7 @@ static MenuItem* find_nextitem(Menu* menu, MenuItem* menuitem)
 
   for (; it != end; ++it) {
     Widget* nextitem = *it;
-    if ((nextitem->type == JI_MENUITEM) && nextitem->isEnabled())
+    if ((nextitem->type == kMenuItemWidget) && nextitem->isEnabled())
       return static_cast<MenuItem*>(nextitem);
   }
 
@@ -1275,7 +1275,7 @@ static MenuItem* find_previtem(Menu* menu, MenuItem* menuitem)
 
   for (; it != end; ++it) {
     Widget* nextitem = *it;
-    if ((nextitem->type == JI_MENUITEM) && nextitem->isEnabled())
+    if ((nextitem->type == kMenuItemWidget) && nextitem->isEnabled())
       return static_cast<MenuItem*>(nextitem);
   }
 
diff --git a/src/ui/menu.h b/src/ui/menu.h
index dd412da00..b64274ca8 100644
--- a/src/ui/menu.h
+++ b/src/ui/menu.h
@@ -57,7 +57,7 @@ namespace ui {
   class MenuBox : public Widget
   {
   public:
-    MenuBox(int type = JI_MENUBOX);
+    MenuBox(WidgetType type = kMenuBoxWidget);
     ~MenuBox();
 
     Menu* getMenu();
diff --git a/src/ui/message.cpp b/src/ui/message.cpp
index 30d5df6ad..11a7d6b5b 100644
--- a/src/ui/message.cpp
+++ b/src/ui/message.cpp
@@ -140,7 +140,7 @@ void jmessage_broadcast_to_parents(Message* msg, Widget* widget)
   ASSERT(msg != NULL);
   ASSERT_VALID_WIDGET(widget);
 
-  if (widget && widget->type != JI_MANAGER) {
+  if (widget && widget->type != kManagerWidget) {
     jmessage_add_dest(msg, widget);
     jmessage_broadcast_to_parents(msg, widget->getParent());
   }
diff --git a/src/ui/scroll_bar.cpp b/src/ui/scroll_bar.cpp
index d73a0e7b6..9a82af6ef 100644
--- a/src/ui/scroll_bar.cpp
+++ b/src/ui/scroll_bar.cpp
@@ -22,7 +22,7 @@ int ScrollBar::m_wherepos = 0;
 int ScrollBar::m_whereclick = 0;
 
 ScrollBar::ScrollBar(int align)
-  : Widget(JI_VIEW_SCROLLBAR)
+  : Widget(kViewScrollbarWidget)
   , m_pos(0)
   , m_size(0)
 {
diff --git a/src/ui/separator.cpp b/src/ui/separator.cpp
index 3a5e1cf80..8120be7ad 100644
--- a/src/ui/separator.cpp
+++ b/src/ui/separator.cpp
@@ -18,7 +18,7 @@ using namespace gfx;
 namespace ui {
 
 Separator::Separator(const char* text, int align)
- : Widget(JI_SEPARATOR)
+ : Widget(kSeparatorWidget)
 {
   setAlign(align);
   setText(text);
diff --git a/src/ui/slider.cpp b/src/ui/slider.cpp
index c4009ce7f..7272bd1d0 100644
--- a/src/ui/slider.cpp
+++ b/src/ui/slider.cpp
@@ -25,7 +25,7 @@ static int slider_press_value;
 static int slider_press_left;
 
 Slider::Slider(int min, int max, int value)
-  : Widget(JI_SLIDER)
+  : Widget(kSliderWidget)
 {
   m_min = min;
   m_max = max;
diff --git a/src/ui/splitter.cpp b/src/ui/splitter.cpp
index aee50cff9..1efa08af8 100644
--- a/src/ui/splitter.cpp
+++ b/src/ui/splitter.cpp
@@ -22,7 +22,7 @@ using namespace gfx;
 namespace ui {
 
 Splitter::Splitter(Type type, int align)
-  : Widget(JI_SPLITTER)
+  : Widget(kSplitterWidget)
   , m_type(type)
   , m_pos(50)
 {
diff --git a/src/ui/textbox.cpp b/src/ui/textbox.cpp
index a95201aa2..ec901fa1e 100644
--- a/src/ui/textbox.cpp
+++ b/src/ui/textbox.cpp
@@ -21,7 +21,7 @@
 namespace ui {
 
 TextBox::TextBox(const char* text, int align)
- : Widget(JI_TEXTBOX)
+ : Widget(kTextBoxWidget)
 {
   setFocusStop(true);
   setAlign(align);
diff --git a/src/ui/tooltips.cpp b/src/ui/tooltips.cpp
index 67871e498..d3babd1fa 100644
--- a/src/ui/tooltips.cpp
+++ b/src/ui/tooltips.cpp
@@ -24,7 +24,7 @@ using namespace gfx;
 namespace ui {
 
 TooltipManager::TooltipManager()
-  : Widget(JI_WIDGET)
+  : Widget(kGenericWidget)
 {
   Manager* manager = Manager::getDefault();
   manager->addMessageFilter(JM_MOUSEENTER, this);
diff --git a/src/ui/view.cpp b/src/ui/view.cpp
index 72b035c1c..72138cc09 100644
--- a/src/ui/view.cpp
+++ b/src/ui/view.cpp
@@ -23,7 +23,7 @@ using namespace gfx;
 namespace ui {
 
 View::View()
-  : Widget(JI_VIEW)
+  : Widget(kViewWidget)
   , m_scrollbar_h(JI_HORIZONTAL)
   , m_scrollbar_v(JI_VERTICAL)
 {
@@ -227,9 +227,9 @@ Rect View::getViewportBounds()
 View* View::getView(Widget* widget)
 {
   if ((widget->getParent()) &&
-      (widget->getParent()->type == JI_VIEW_VIEWPORT) &&
+      (widget->getParent()->type == kViewViewportWidget) &&
       (widget->getParent()->getParent()) &&
-      (widget->getParent()->getParent()->type == JI_VIEW))
+      (widget->getParent()->getParent()->type == kViewWidget))
     return static_cast<View*>(widget->getParent()->getParent());
   else
     return 0;
diff --git a/src/ui/viewport.cpp b/src/ui/viewport.cpp
index 3085b4eb0..5e8131cd8 100644
--- a/src/ui/viewport.cpp
+++ b/src/ui/viewport.cpp
@@ -19,7 +19,7 @@ using namespace gfx;
 namespace ui {
 
 Viewport::Viewport()
-  : Widget(JI_VIEW_VIEWPORT)
+  : Widget(kViewViewportWidget)
 {
   initTheme();
 }
diff --git a/src/ui/widget.cpp b/src/ui/widget.cpp
index f97942b9e..99ac9a0f2 100644
--- a/src/ui/widget.cpp
+++ b/src/ui/widget.cpp
@@ -33,13 +33,13 @@ static inline void mark_dirty_flag(Widget* widget)
   }
 }
 
-int ji_register_widget_type()
+WidgetType register_widget_type()
 {
-  static int type = JI_USER_WIDGET;
-  return type++;
+  static int type = (int)kFirstUserWidget;
+  return (WidgetType)type++;
 }
 
-Widget::Widget(int type)
+Widget::Widget(WidgetType type)
 {
   addWidget(this);
 
@@ -80,7 +80,7 @@ Widget::Widget(int type)
 Widget::~Widget()
 {
   // Break relationship with the manager.
-  if (this->type != JI_MANAGER) {
+  if (this->type != kManagerWidget) {
     Manager* manager = getManager();
     manager->freeWidget(this);
     manager->removeMessagesFor(this);
@@ -341,7 +341,7 @@ Window* Widget::getRoot()
   Widget* widget = this;
 
   while (widget) {
-    if (widget->type == JI_WINDOW)
+    if (widget->type == kWindowWidget)
       return dynamic_cast<Window*>(widget);
 
     widget = widget->m_parent;
@@ -355,7 +355,7 @@ Manager* Widget::getManager()
   Widget* widget = this;
 
   while (widget) {
-    if (widget->type == JI_MANAGER)
+    if (widget->type == kManagerWidget)
       return static_cast<Manager*>(widget);
 
     widget = widget->m_parent;
@@ -609,7 +609,7 @@ void Widget::setBorder(const Border& br)
 
 void Widget::getRegion(gfx::Region& region)
 {
-  if (this->type == JI_WINDOW)
+  if (this->type == kWindowWidget)
     getTheme()->getWindowMask(this, region);
   else
     region = getBounds();
diff --git a/src/ui/widget.h b/src/ui/widget.h
index d55dcec87..48f9c5498 100644
--- a/src/ui/widget.h
+++ b/src/ui/widget.h
@@ -17,6 +17,7 @@
 #include "ui/color.h"
 #include "ui/component.h"
 #include "ui/rect.h"
+#include "ui/widget_type.h"
 #include "ui/widgets_list.h"
 
 #define ASSERT_VALID_WIDGET(widget) ASSERT((widget) != NULL)
@@ -37,7 +38,7 @@ namespace ui {
   class Theme;
   class Window;
 
-  int ji_register_widget_type();
+  WidgetType register_widget_type();
 
   // Position and geometry
 
@@ -61,7 +62,7 @@ namespace ui {
   class Widget : public Component
   {
   public:
-    int type;                     /* widget's type */
+    WidgetType type;              // widget's type
 
     JRect rc;                     /* position rectangle */
     struct {
@@ -87,7 +88,7 @@ namespace ui {
     // CTOR & DTOR
     // ===============================================================
 
-    Widget(int type);
+    Widget(WidgetType type);
     virtual ~Widget();
 
     // Safe way to delete a widget when it is not in the manager message
@@ -96,7 +97,7 @@ namespace ui {
 
     // Main properties.
 
-    int getType() const { return this->type; }
+    WidgetType getType() const { return this->type; }
 
     const std::string& getId() const { return m_id; }
     void setId(const char* id) { m_id = id; }
diff --git a/src/ui/widget_type.h b/src/ui/widget_type.h
new file mode 100644
index 000000000..062bf7f8a
--- /dev/null
+++ b/src/ui/widget_type.h
@@ -0,0 +1,50 @@
+// ASEPRITE gui library
+// Copyright (C) 2001-2013  David Capello
+//
+// This source file is distributed under a BSD-like license, please
+// read LICENSE.txt for more information.
+
+#ifndef UI_WIDGET_TYPE_H_INCLUDED
+#define UI_WIDGET_TYPE_H_INCLUDED
+
+namespace ui {
+
+  // Widget types.
+  enum WidgetType {
+    // Undefined (or anonymous) widget type.
+    kGenericWidget,
+
+    // Known widgets.
+    kBoxWidget,
+    kButtonWidget,
+    kCheckWidget,
+    kComboBoxWidget,
+    kEntryWidget,
+    kGridWidget,
+    kImageViewWidget,
+    kLabelWidget,
+    kListBoxWidget,
+    kListItemWidget,
+    kManagerWidget,
+    kMenuWidget,
+    kMenuBarWidget,
+    kMenuBoxWidget,
+    kMenuItemWidget,
+    kSplitterWidget,
+    kRadioWidget,
+    kSeparatorWidget,
+    kSliderWidget,
+    kTextBoxWidget,
+    kViewWidget,
+    kViewScrollbarWidget,
+    kViewViewportWidget,
+    kWindowWidget,
+
+    // User widgets.
+    kFirstUserWidget,
+    kLastUserWidget = 0x7fffffff
+  };
+
+} // namespace ui
+
+#endif  // UI_WIDGET_TYPE_H_INCLUDED
diff --git a/src/ui/window.cpp b/src/ui/window.cpp
index 80552fdaf..0841fd5fc 100644
--- a/src/ui/window.cpp
+++ b/src/ui/window.cpp
@@ -34,7 +34,7 @@ static int press_x, press_y;
 static void displace_widgets(Widget* widget, int x, int y);
 
 Window::Window(bool desktop, const char* text)
-  : Widget(JI_WINDOW)
+  : Widget(kWindowWidget)
 {
   m_killer = NULL;
   m_isDesktop = desktop;
diff --git a/src/widgets/button_set.cpp b/src/widgets/button_set.cpp
index 101eea906..d288280fc 100644
--- a/src/widgets/button_set.cpp
+++ b/src/widgets/button_set.cpp
@@ -39,7 +39,7 @@ class ButtonSet::Item : public RadioButton
 {
 public:
   Item(int index, int radioGroup, int b1, int b2, int b3, int b4)
-    : RadioButton(NULL, radioGroup, JI_BUTTON)
+    : RadioButton(NULL, radioGroup, kButtonWidget)
     , m_index(index)
   {
     setRadioGroup(radioGroup);
diff --git a/src/widgets/color_bar.cpp b/src/widgets/color_bar.cpp
index 6111b9765..70acd4ce0 100644
--- a/src/widgets/color_bar.cpp
+++ b/src/widgets/color_bar.cpp
@@ -77,7 +77,7 @@ ColorBar* ColorBar::m_instance = NULL;
 
 ColorBar::ColorBar(int align)
   : Box(align)
-  , m_paletteButton("Edit Palette", JI_BUTTON)
+  , m_paletteButton("Edit Palette", kButtonWidget)
   , m_paletteView(false)
   , m_fgColor(app::Color::fromIndex(15), IMAGE_INDEXED)
   , m_bgColor(app::Color::fromIndex(0), IMAGE_INDEXED)
diff --git a/src/widgets/color_button.cpp b/src/widgets/color_button.cpp
index aa1d6a957..d8ecd5f95 100644
--- a/src/widgets/color_button.cpp
+++ b/src/widgets/color_button.cpp
@@ -37,16 +37,16 @@
 
 using namespace ui;
 
-static int colorbutton_type()
+static WidgetType colorbutton_type()
 {
-  static int type = 0;
-  if (!type)
-    type = ji_register_widget_type();
+  static WidgetType type = kGenericWidget;
+  if (type == kGenericWidget)
+    type = register_widget_type();
   return type;
 }
 
 ColorButton::ColorButton(const app::Color& color, PixelFormat pixelFormat)
-  : ButtonBase("", colorbutton_type(), JI_BUTTON, JI_BUTTON)
+  : ButtonBase("", colorbutton_type(), kButtonWidget, kButtonWidget)
   , m_color(color)
   , m_pixelFormat(pixelFormat)
   , m_window(NULL)
diff --git a/src/widgets/color_selector.cpp b/src/widgets/color_selector.cpp
index e584b727c..8800d018f 100644
--- a/src/widgets/color_selector.cpp
+++ b/src/widgets/color_selector.cpp
@@ -43,11 +43,11 @@ ColorSelector::ColorSelector()
   , m_vbox(JI_VERTICAL)
   , m_topBox(JI_HORIZONTAL)
   , m_colorPalette(false)
-  , m_indexButton("Index", 1, JI_BUTTON)
-  , m_rgbButton("RGB", 1, JI_BUTTON)
-  , m_hsvButton("HSB", 1, JI_BUTTON)
-  , m_grayButton("Gray", 1, JI_BUTTON)
-  , m_maskButton("Mask", 1, JI_BUTTON)
+  , m_indexButton("Index", 1, kButtonWidget)
+  , m_rgbButton("RGB", 1, kButtonWidget)
+  , m_hsvButton("HSB", 1, kButtonWidget)
+  , m_grayButton("Gray", 1, kButtonWidget)
+  , m_maskButton("Mask", 1, kButtonWidget)
   , m_maskLabel("Transparent Color Selected")
   , m_disableHexUpdate(false)
 {
diff --git a/src/widgets/color_sliders.cpp b/src/widgets/color_sliders.cpp
index 2dbea2c35..506a9bd96 100644
--- a/src/widgets/color_sliders.cpp
+++ b/src/widgets/color_sliders.cpp
@@ -91,7 +91,7 @@ namespace {
 // ColorSliders
 
 ColorSliders::ColorSliders()
-  : Widget(JI_WIDGET)
+  : Widget(kGenericWidget)
   , m_grid(3, false)
 {
   addChild(&m_grid);
diff --git a/src/widgets/editor/editor.cpp b/src/widgets/editor/editor.cpp
index e1fff10fb..acba1971a 100644
--- a/src/widgets/editor/editor.cpp
+++ b/src/widgets/editor/editor.cpp
@@ -175,11 +175,11 @@ Editor::~Editor()
   delete m_fgColorChangeSlot;
 }
 
-int editor_type()
+WidgetType editor_type()
 {
-  static int type = 0;
-  if (!type)
-    type = ji_register_widget_type();
+  static WidgetType type = kGenericWidget;
+  if (type == kGenericWidget)
+    type = register_widget_type();
   return type;
 }
 
diff --git a/src/widgets/editor/editor.h b/src/widgets/editor/editor.h
index f10c66937..f3277f439 100644
--- a/src/widgets/editor/editor.h
+++ b/src/widgets/editor/editor.h
@@ -236,6 +236,6 @@ private:
   widgets::DocumentView* m_docView;
 };
 
-int editor_type();
+ui::WidgetType editor_type();
 
 #endif
diff --git a/src/widgets/file_list.cpp b/src/widgets/file_list.cpp
index 718bb16a2..2a4c4328e 100644
--- a/src/widgets/file_list.cpp
+++ b/src/widgets/file_list.cpp
@@ -36,7 +36,7 @@ using namespace ui;
 namespace widgets {
 
 FileList::FileList()
-  : Widget(JI_WIDGET)
+  : Widget(kGenericWidget)
   , m_generateThumbnailTimer(200, this)
   , m_monitoringTimer(50, this)
 {
diff --git a/src/widgets/palette_view.cpp b/src/widgets/palette_view.cpp
index cd126544f..68ea91c04 100644
--- a/src/widgets/palette_view.cpp
+++ b/src/widgets/palette_view.cpp
@@ -43,11 +43,11 @@
 
 using namespace ui;
 
-int palette_view_type()
+WidgetType palette_view_type()
 {
-  static int type = 0;
-  if (!type)
-    type = ji_register_widget_type();
+  static WidgetType type = kGenericWidget;
+  if (type == kGenericWidget)
+    type = register_widget_type();
   return type;
 }
 
diff --git a/src/widgets/palette_view.h b/src/widgets/palette_view.h
index 52e9a639f..5a5373a7f 100644
--- a/src/widgets/palette_view.h
+++ b/src/widgets/palette_view.h
@@ -67,6 +67,6 @@ private:
   bool m_isUpdatingColumns;
 };
 
-int palette_view_type();
+ui::WidgetType palette_view_type();
 
 #endif
diff --git a/src/widgets/status_bar.cpp b/src/widgets/status_bar.cpp
index fb3e42693..ae72bdb56 100644
--- a/src/widgets/status_bar.cpp
+++ b/src/widgets/status_bar.cpp
@@ -90,11 +90,11 @@ private:
 static void slider_change_hook(Slider* slider);
 static void ani_button_command(Button* widget, AniAction action);
 
-static int statusbar_type()
+static WidgetType statusbar_type()
 {
-  static int type = 0;
-  if (!type)
-    type = ji_register_widget_type();
+  static WidgetType type = kGenericWidget;
+  if (type == kGenericWidget)
+    type = register_widget_type();
   return type;
 }
 
diff --git a/src/widgets/tabs.cpp b/src/widgets/tabs.cpp
index 6accd3e00..b6b2044ad 100644
--- a/src/widgets/tabs.cpp
+++ b/src/widgets/tabs.cpp
@@ -39,11 +39,11 @@ using namespace ui;
 
 #define HAS_ARROWS(tabs) ((m_button_left->getParent() == (tabs)))
 
-static int tabs_type()
+static WidgetType tabs_type()
 {
-  static int type = 0;
-  if (!type)
-    type = ji_register_widget_type();
+  static WidgetType type = kGenericWidget;
+  if (type == kGenericWidget)
+    type = register_widget_type();
   return type;
 }
 
diff --git a/src/widgets/toolbar.cpp b/src/widgets/toolbar.cpp
index 43863a104..80017df31 100644
--- a/src/widgets/toolbar.cpp
+++ b/src/widgets/toolbar.cpp
@@ -86,7 +86,7 @@ static Size getToolIconSize(Widget* widget)
 ToolBar* ToolBar::m_instance = NULL;
 
 ToolBar::ToolBar()
-  : Widget(JI_WIDGET)
+  : Widget(kGenericWidget)
   , m_tipTimer(300, this)
 {
   m_instance = this;
@@ -576,7 +576,7 @@ void ToolBar::onClosePopup()
 //////////////////////////////////////////////////////////////////////
 
 ToolStrip::ToolStrip(ToolGroup* group, ToolBar* toolbar)
-  : Widget(JI_WIDGET)
+  : Widget(kGenericWidget)
 {
   m_group = group;
   m_hot_tool = NULL;