Feature/scroll indication (#3)

Add scroll arrows when there are more items in the list than the list can show at a time.

These arrows can be shown in the main menu (although there aren't enough items in there to have them shown) or in the various DistributionEventPokemonListScene menus.

I also did provisions to support the same for the ScrollWidget in the about screen. Although I haven't implemented that (yet?)

include/core/DragonUtils.h

@@ -3,13 +3,13 @@
 
 #include <libdragon.h>
 
-enum class UINavigationKey
+enum class UINavigationDirection
 {
-    NONE,
     UP,
     RIGHT,
     DOWN,
-    LEFT
+    LEFT,
+    MAX
 };
 
 enum class NavigationInputSourceType
@@ -24,6 +24,6 @@ enum class NavigationInputSourceType
  * This function determines whether the joypad_inputs_t has analog or dpad positions/presses that could be considered for UI navigation.
  * If so, it will return the most prominent direction.
  */
-const UINavigationKey determineUINavigationKey(joypad_inputs_t inputs, NavigationInputSourceType sourceType);
+const UINavigationDirection determineUINavigationDirection(joypad_inputs_t inputs, NavigationInputSourceType sourceType);
 
 #endif

include/scenes/MenuScene.h

@@ -3,11 +3,13 @@
 
 #include "scenes/SceneWithDialogWidget.h"
 #include "widget/VerticalList.h"
+#include "widget/ImageWidget.h"
 #include "widget/DialogWidget.h"
 #include "widget/CursorWidget.h"
 #include "widget/MenuItemWidget.h"
 #include "widget/ListItemFiller.h"
 #include "widget/IFocusListener.h"
+#include "widget/IScrollWindowListener.h"
 
 typedef struct MenuSceneContext
 {
@@ -20,7 +22,7 @@ typedef struct MenuSceneContext
  * @brief A scene showing a menu
  * 
  */
-class MenuScene : public SceneWithDialogWidget, public IFocusListener
+class MenuScene : public SceneWithDialogWidget, public IFocusListener, public IScrollWindowListener
 {
 public:
     MenuScene(SceneDependencies& deps, void* context);
@@ -36,6 +38,7 @@ public:
     virtual void onDialogDone();
 
     void focusChanged(const FocusChangeStatus& status) override;
+    void onScrollWindowChanged(const ScrollWindowUpdate& update) override;
 
     SceneDependencies& getDependencies();
 
@@ -47,7 +50,11 @@ protected:
     MenuSceneContext* context_;
     sprite_t* menu9SliceSprite_;
     sprite_t* cursorSprite_;
+    sprite_t* uiArrowUpSprite_;
+    sprite_t* uiArrowDownSprite_;
     VerticalList menuList_;
+    ImageWidget scrollArrowUp_;
+    ImageWidget scrollArrowDown_;
     CursorWidget cursorWidget_;
     ListItemFiller<VerticalList, MenuItemData, MenuItemWidget, MenuItemStyle>  menuListFiller_;
     WidgetFocusChainSegment listFocusChainSegment_;

include/widget/IScrollWindowListener.h

@@ -0,0 +1,54 @@
+#ifndef ISCROLLWINDOWLISTENER_H
+#define ISCROLLWINDOWLISTENER_H
+
+#include "core/common.h"
+#include "core/DragonUtils.h"
+
+/**
+ * This struct contains the various things to know about the scroll window
+ * when it has been changed.
+ */
+typedef struct ScrollWindowUpdate
+{
+    /**
+     * The coords and size of the scroll window relative to the widget
+     * that implements the scrolling
+     */
+    Rectangle scrollWindowRectangle;
+    /**
+     * The total size of the panel containing all of the widgets in the scrolling widget.
+     * this includes the parts that aren't visible (because they're not in the scroll window)
+     */
+    Dimensions totalSize;
+} ScrollWindowUpdate;
+
+bool canScrollTo(const ScrollWindowUpdate& info, UINavigationDirection direction);
+
+/**
+ * This class allows you to react to changes to the scroll window of a widget.
+ * This is useful for showing UI indications like scrollbars or "more" arrows
+ */
+class IScrollWindowListener
+{
+public:
+    virtual ~IScrollWindowListener();
+
+    virtual void onScrollWindowChanged(const ScrollWindowUpdate& update) = 0;
+protected:
+private:
+};
+
+/**
+ * Test implementation that will just print the scroll window update
+ */
+class TestScrollWindowListener : public IScrollWindowListener
+{
+public:
+    virtual ~TestScrollWindowListener();
+
+    void onScrollWindowChanged(const ScrollWindowUpdate& update) override;
+protected:
+private:
+};
+
+#endif

include/widget/ScrollWidget.h

@@ -5,11 +5,13 @@
 #include "animations/IAnimation.h"
 #include <vector>
 
-typedef std::vector<IWidget*> WidgetList;
-
+class IScrollWindowListener;
 class ScrollWidget;
 class AnimationManager;
 
+typedef std::vector<IWidget*> WidgetList;
+typedef std::vector<IScrollWindowListener*> ScrollWindowListenerList;
+
 typedef struct ScrollWidgetStyle
 {
     // it defines the amount of pixels we should scroll when the analog stick or dpad is used.
@@ -84,16 +86,8 @@ public:
      */
     void setWindowStart(const Point& windowStart);
 
-    /**
-     * @brief Indicates the percentage at which the current window position is at horizontally
-     *  in relation to the entire window
-     */
-    float getWindowProgressX() const;
-    /**
-     * @brief Indicates the percentage at which the current window position is at vertically
-     *  in relation to the entire window
-     */
-    float getWindowProgressY() const;
+    void registerScrollWindowListener(IScrollWindowListener* listener);
+    void unregisterScrollWindowListener(IScrollWindowListener* listener);
 protected:
 private:
     /**
@@ -107,8 +101,11 @@ private:
      */
     void recalculateWindowSize();
 
+    void notifyScrollWindowListeners();
+
     MoveScrollWidgetWindowAnimation windowAnimation_;
     WidgetList widgets_;
+    ScrollWindowListenerList scrollWindowListeners_;
     ScrollWidgetStyle style_;
     AnimationManager& animManager_;
     Rectangle bounds_;

include/widget/VerticalList.h

@@ -11,13 +11,14 @@ class RDPQGraphics;
 class IWidget;
 class VerticalList;
 class AnimationManager;
+struct FocusChangeStatus;
+class IFocusListener;
+class IScrollWindowListener;
 
 typedef std::vector<IWidget*> IWidgetList;
 typedef std::vector<Rectangle> WidgetBoundsList;
-
-struct FocusChangeStatus;
-class IFocusListener;
 typedef std::vector<IFocusListener*> FocusListenerList;
+typedef std::vector<IScrollWindowListener*> ScrollWindowListenerList;
 
 /**
  * @brief This Animation implementation is used internal in VerticalList
@@ -138,6 +139,7 @@ public:
     bool focusPrevious();
 
     void addWidget(IWidget* widget);
+    void removeWidget(IWidget* widget);
     void clearWidgets();
 
     VerticalListStyle& getStyle();
@@ -160,6 +162,10 @@ public:
 
     void registerFocusListener(IFocusListener* listener);
     void unregisterFocusListener(IFocusListener* listener);
+
+    void registerScrollWindowListener(IScrollWindowListener* listener);
+    void unregisterScrollWindowListener(IScrollWindowListener* listener);
+    void notifyScrollWindowListeners();
 protected:
 private:
     void rebuildLayout();
@@ -176,6 +182,7 @@ private:
     IWidgetList widgetList_;
     WidgetBoundsList widgetBoundsList_;
     FocusListenerList focusListeners_;
+    ScrollWindowListenerList scrollWindowListeners_;
     VerticalListStyle listStyle_;
     Rectangle bounds_;
     uint32_t windowMinY_;