diff --git a/samples/main.cpp b/samples/main.cpp
index bfb60bc..5fd507b 100644
--- a/samples/main.cpp
+++ b/samples/main.cpp
@@ -31,7 +31,7 @@ static constexpr Id RootPanelId = 1;
 
 static constexpr Id NextPanelId = 100;
 
-int quit(uint32_t, void *instance) {
+int quit(Id, void *instance) {
     if (instance == nullptr) {
         return ErrorCode;
     }
@@ -46,7 +46,7 @@ static uint32_t LastTick = 0;
 static uint32_t Diff = 0;
 static constexpr uint32_t TimeDiff = 10;
 
-int updateProgressbar(uint32_t, void *instance) {
+int updateProgressbar(Id, void *instance) {
     if (instance == nullptr) {
         return ErrorCode;
     }
diff --git a/src/tinyui.cpp b/src/tinyui.cpp
index ff25acc..3720e55 100644
--- a/src/tinyui.cpp
+++ b/src/tinyui.cpp
@@ -41,7 +41,7 @@ static Style DefaultStyle {
     { "Arial.ttf", 35, nullptr }
 };
 
-static const char *SeverityToken[] = {
+static constexpr char const *SeverityToken[] = {
     "",
     "*TRACE*",
     "*DEBUG*",
@@ -57,7 +57,7 @@ void log_message(LogSeverity severity, const char *message) {
 
 Context *gCtx = nullptr;
 
-Context *Context::create(const char *title, Style &style) {
+Context *Context::create(const char *title, const Style &style) {
     Context *ctx = new Context;
     ctx->mLogger = log_message;
     ctx->mAppTitle = title;
@@ -71,7 +71,7 @@ void Context::destroy(Context *ctx) {
     delete ctx;
 }
 
-bool TinyUi::createContext(const char *title, Style &style) {
+bool TinyUi::createContext(const char *title, const Style &style) {
     if (gCtx != nullptr) {
         return false;
     }
diff --git a/src/tinyui.h b/src/tinyui.h
index 44b8643..d6a30b2 100644
--- a/src/tinyui.h
+++ b/src/tinyui.h
@@ -74,6 +74,9 @@ struct Widget;
 
 // Type declarations ----------------------------------------------------------
 
+/// @brief This enum is used to describe the alignment of a widget.
+using Id = uint64_t;
+
 /// @brief The return code type used in the ui library.
 using ret_code = int32_t;
 
@@ -319,7 +322,7 @@ struct EventPayload {
 /// @brief This interface is used to store all neede message handlers.
 struct CallbackI {
     /// The function callback
-    typedef int (*funcCallback) (uint32_t id, void *data);
+    typedef int (*funcCallback) (Id id, void *data);
     /// The function callback array, not handled callbacks are marked as a nullptr.
     funcCallback mfuncCallback[Events::NumEvents];
     /// The data instance.
@@ -336,7 +339,7 @@ struct CallbackI {
     /// @param callbackFunc The callback function.
     /// @param instance The instance to use.
     /// @param eventType The event type to use.
-    CallbackI(funcCallback callbackFunc, void *instance, size_t eventType = Events::MouseButtonDownEvent) :
+     CallbackI(funcCallback callbackFunc, void *instance, size_t eventType = Events::MouseButtonDownEvent) :
             mfuncCallback{ nullptr }, mInstance(instance) {
         clear();
         mfuncCallback[eventType] = callbackFunc;
@@ -411,7 +414,7 @@ struct Context {
     /// @param title The title of the context.
     /// @param style The style to use.
     /// @return The created context.
-    static Context *create(const char *title, Style &style);
+    static Context *create(const char *title, const Style &style);
     
     /// @brief Will destroy a valid tinyui context.
     /// @param ctx  The context to destroy.
@@ -431,7 +434,7 @@ struct TinyUi {
     /// @param title    The app title.
     /// @param style    The style to use.
     /// @return true if successful.
-    static bool createContext(const char *title, Style &style);
+    static bool createContext(const char *title, const Style &style);
     
     /// @brief Will destroy the context.
     /// @return true if successful.
diff --git a/src/widgets.cpp b/src/widgets.cpp
index 535ae63..802cabb 100644
--- a/src/widgets.cpp
+++ b/src/widgets.cpp
@@ -82,8 +82,7 @@ static Image *loadIntoImageCache(Context &ctx, const char *filename) {
 
 static void releaseImageCache(Context &ctx) {
     for (auto it = ctx.mImageCache.begin(); it != ctx.mImageCache.end(); ++it) {
-        Image *image = it->second;
-        if (image != nullptr) {
+        if (Image *image = it->second; image != nullptr) {
             Renderer::releaseSurfaceImpl(image->mSurfaceImpl);
             delete image;
         }
@@ -125,10 +124,10 @@ static Widget *createWidget(Context &ctx, Id id, Id parentId, const Rect &rect,
     if (widget != nullptr) {
         if (widget->mType == type) {
             return widget;
-        } else {
-            ctx.mLogger(LogSeverity::Error, "A widget with the same id but different type already exists.");
-            return nullptr;
-        } 
+        }
+
+        ctx.mLogger(LogSeverity::Error, "A widget with the same id but different type already exists.");
+        return nullptr;
     }
 
     widget = new Widget;
@@ -344,7 +343,7 @@ ret_code Widgets::imageBox(Id id, Id parentId, const char* image, const Rect& re
     if (ctx.mRoot == nullptr) {
         return InvalidRenderHandle;
     }
-    Widget *child = createWidget(ctx, id, parentId, rect, WidgetType::Box);
+    Widget *child = createWidget(ctx, id, parentId, rect, WidgetType::ImageBox);
     if (child == nullptr) {
         return ErrorCode;
     }
@@ -371,7 +370,7 @@ ret_code Widgets::panel(Id id, Id parentId, const char *title, const Rect &rect,
     return ResultOk;
 }
 
-static int onTreeViewItemClicked(uint32_t id, void *data) {
+static int onTreeViewItemClicked(Id id, void *data) {
     Widget *treeView = Widgets::findWidget(id, TinyUi::getContext().mRoot);
     if (treeView == nullptr) {
         return ErrorCode;
@@ -437,7 +436,8 @@ ret_code Widgets::treeItem(Id id, Id parentItemId, const char *text) {
     const int32_t w = parentRect.width;
     const int32_t h = parentRect.height;
     size_t numChildren = parentWidget->mChildren.size() + 1;
-    const Rect rect(parentRect.top.x + margin, parentRect.top.y + numChildren * margin + numChildren * h, w, h);
+    const Rect rect(parentRect.top.x + margin, parentRect.top.y + numChildren * margin +
+        static_cast<int32_t>(numChildren) * h, w, h);
     Widget *child = createWidget(ctx, id, parentItemId, rect, WidgetType::Label);
     if (child == nullptr) {
         return ErrorCode;
@@ -568,6 +568,15 @@ static void render(Context &ctx, Widget *currentWidget) {
                 Renderer::drawRect(ctx, r.top.x, r.top.y, r.width, r.height, currentWidget->mFilledRect, ctx.mStyle.mBorder);
             }
             break;
+
+        case WidgetType::ImageBox:
+            {
+                Renderer::drawRect(ctx, r.top.x, r.top.y, r.width, r.height, currentWidget->mFilledRect, ctx.mStyle.mBorder);
+                if (currentWidget->mImage != nullptr) {
+                    Renderer::drawImage(ctx, r.top.x, r.top.y, r.width, r.height, currentWidget->mImage);
+                }
+            }
+            break;
     }
 
     for (auto &child : currentWidget->mChildren) {
diff --git a/src/widgets.h b/src/widgets.h
index 4e897a1..08e224f 100644
--- a/src/widgets.h
+++ b/src/widgets.h
@@ -36,10 +36,11 @@ enum class WidgetType {
     Container = 0,      ///< A container widget
     Button,             ///< A button widget
     Label,              ///< A label widget
-    InputField,         ///< 
+    InputField,         ///< An input field widget
     Panel,              ///< A panel widget
     Box,                ///< A box widget
-    TreeView,           ///< A treeeview widget
+    ImageBox,           ///< An image box widget
+    TreeView,           ///< A treeview widget
     ProgressBar,        ///< A status bar widget
     Count               ///< The number of widgets
 };
@@ -56,10 +57,7 @@ struct FilledState {
     uint32_t filledState{0};    ///< The filled state in percent (0-100)
 };
 
-/// @brief This enum is used to descripe the alignment of a widget.
-using Id = uint64_t;
-
-/// @brief This enum is used to descripe the alignment of a widget.
+/// @brief This enum is used to describe the alignment of a widget.
 enum class WidgetStyle {
     Invalid = -1,
     BorderStyle,        ///< The widget has a border