Merge scrollarea classes into one.

9 files changed, 791 insertions, 23 deletions

diff --git a/src/gui/widgets/basiccontainer.cpp b/src/gui/widgets/basiccontainer.cpp
index 48ab683be..d3dd62fc7 100644
--- a/src/gui/widgets/basiccontainer.cpp
+++ b/src/gui/widgets/basiccontainer.cpp
@@ -313,7 +313,7 @@ void BasicContainer::logicChildren()
     BLOCK_END("BasicContainer::logicChildren")
 }
 
-void BasicContainer::showWidgetPart(Widget* widget, Rect area)
+void BasicContainer::showWidgetPart(Widget *const widget, Rect area)
 {
     const Rect widgetArea = getChildrenArea();
 
diff --git a/src/gui/widgets/basiccontainer.h b/src/gui/widgets/basiccontainer.h
index 240e9375f..bf018e0de 100644
--- a/src/gui/widgets/basiccontainer.h
+++ b/src/gui/widgets/basiccontainer.h
@@ -106,7 +106,7 @@ class BasicContainer : public Widget,
           *               itself to be visible.
           * @param rectangle The rectangle to be visible.
           */
-        virtual void showWidgetPart(Widget* widget, Rect area);
+        virtual void showWidgetPart(Widget *const widget, Rect area);
 
         // Inherited from Widget
 
diff --git a/src/gui/widgets/scrollarea.cpp b/src/gui/widgets/scrollarea.cpp
index dcc3a871b..3c50abca0 100644
--- a/src/gui/widgets/scrollarea.cpp
+++ b/src/gui/widgets/scrollarea.cpp
@@ -20,6 +20,49 @@
  *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+/*      _______   __   __   __   ______   __   __   _______   __   __
+ *     / _____/\ / /\ / /\ / /\ / ____/\ / /\ / /\ / ___  /\ /  |\/ /\
+ *    / /\____\// / // / // / // /\___\// /_// / // /\_/ / // , |/ / /
+ *   / / /__   / / // / // / // / /    / ___  / // ___  / // /| ' / /
+ *  / /_// /\ / /_// / // / // /_/_   / / // / // /\_/ / // / |  / /
+ * /______/ //______/ //_/ //_____/\ /_/ //_/ //_/ //_/ //_/ /|_/ /
+ * \______\/ \______\/ \_\/ \_____\/ \_\/ \_\/ \_\/ \_\/ \_\/ \_\/
+ *
+ * Copyright (c) 2004 - 2008 Olof Naessén and Per Larsson
+ *
+ *
+ * Per Larsson a.k.a finalman
+ * Olof Naessén a.k.a jansem/yakslem
+ *
+ * Visit: http://guichan.sourceforge.net
+ *
+ * License: (BSD)
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name of Guichan nor the names of its contributors may
+ *    be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
+ * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
 #include "gui/widgets/scrollarea.h"
 
 #include "client.h"
@@ -53,8 +96,29 @@ ScrollArea::ScrollArea(Widget2 *const widget2,
                        Widget *const widget,
                        const bool opaque,
                        const std::string &skin) :
-    gcn::ScrollArea(widget2, widget),
+    BasicContainer(widget2),
+    MouseListener(),
     WidgetListener(),
+    mVScroll(0),
+    mHScroll(0),
+    mScrollbarWidth(12),
+    mHPolicy(SHOW_AUTO),
+    mVPolicy(SHOW_AUTO),
+    mVBarVisible(false),
+    mHBarVisible(false),
+    mUpButtonPressed(false),
+    mDownButtonPressed(false),
+    mLeftButtonPressed(false),
+    mRightButtonPressed(false),
+    mUpButtonScrollAmount(10),
+    mDownButtonScrollAmount(10),
+    mLeftButtonScrollAmount(10),
+    mRightButtonScrollAmount(10),
+    mIsVerticalMarkerDragged(false),
+    mIsHorizontalMarkerDragged(false),
+    mHorizontalMarkerDragOffset(0),
+    mVerticalMarkerDragOffset(0),
+    mOpaque(true),
     mX(0),
     mY(0),
     mClickX(0),
@@ -68,6 +132,8 @@ ScrollArea::ScrollArea(Widget2 *const widget2,
     mHasMouse(false),
     mRedraw(true)
 {
+    setContent(widget);
+    addMouseListener(this);
     mOpaque = opaque;
     init(skin);
 }
@@ -102,6 +168,8 @@ ScrollArea::~ScrollArea()
     mVertexes = nullptr;
     delete mVertexes2;
     mVertexes2 = nullptr;
+
+    setContent(nullptr);
 }
 
 void ScrollArea::init(std::string skinName)
@@ -178,20 +246,30 @@ void ScrollArea::logic()
         return;
     }
 
-    gcn::ScrollArea::logic();
+    checkPolicies();
+
+    setVerticalScrollAmount(getVerticalScrollAmount());
+    setHorizontalScrollAmount(getHorizontalScrollAmount());
+
     Widget *const content = getContent();
+    if (content)
+    {
+        const int frameSize = content->getFrameSize();
+        content->setPosition(-mHScroll + frameSize, -mVScroll + frameSize);
+        content->logic();
+    }
 
     // When no scrollbar in a certain direction, adapt content size to match
     // the content dimension exactly.
     if (content)
     {
         const unsigned int frameSize = 2 * content->getFrameSize();
-        if (mHPolicy == gcn::ScrollArea::SHOW_NEVER)
+        if (mHPolicy == ScrollArea::SHOW_NEVER)
         {
             content->setWidth((mVBarVisible ? (mDimension.width
                 - mScrollbarWidth) : mDimension.width) - frameSize);
         }
-        if (mVPolicy == gcn::ScrollArea::SHOW_NEVER)
+        if (mVPolicy == ScrollArea::SHOW_NEVER)
         {
             content->setHeight((mHBarVisible ? (mDimension.height
                 - mScrollbarWidth) : mDimension.height) - frameSize);
@@ -803,7 +881,13 @@ void ScrollArea::mouseReleased(MouseEvent& event)
                 event.consume();
         }
     }
-    gcn::ScrollArea::mouseReleased(event);
+    mUpButtonPressed = false;
+    mDownButtonPressed = false;
+    mLeftButtonPressed = false;
+    mRightButtonPressed = false;
+    mIsHorizontalMarkerDragged = false;
+    mIsVerticalMarkerDragged = false;
+    event.consume();
     mRedraw = true;
 }
 
@@ -1066,3 +1150,290 @@ Rect ScrollArea::getRightButtonDimension() const
         mScrollbarWidth,
         mScrollbarWidth);
 }
+
+void ScrollArea::setContent(Widget* widget)
+{
+    if (widget)
+    {
+        clear();
+        add(widget);
+        widget->setPosition(0, 0);
+    }
+    else
+    {
+        clear();
+    }
+
+    checkPolicies();
+}
+
+Widget* ScrollArea::getContent()
+{
+    if (!mWidgets.empty())
+        return *mWidgets.begin();
+
+    return nullptr;
+}
+
+void ScrollArea::setHorizontalScrollPolicy(const ScrollPolicy hPolicy)
+{
+    mHPolicy = hPolicy;
+    checkPolicies();
+}
+
+void ScrollArea::setVerticalScrollPolicy(const ScrollPolicy vPolicy)
+{
+    mVPolicy = vPolicy;
+    checkPolicies();
+}
+
+void ScrollArea::setScrollPolicy(const ScrollPolicy hPolicy,
+                                 const ScrollPolicy vPolicy)
+{
+    mHPolicy = hPolicy;
+    mVPolicy = vPolicy;
+    checkPolicies();
+}
+
+void ScrollArea::setVerticalScrollAmount(const int vScroll)
+{
+    const int max = getVerticalMaxScroll();
+
+    mVScroll = vScroll;
+
+    if (vScroll > max)
+        mVScroll = max;
+
+    if (vScroll < 0)
+        mVScroll = 0;
+}
+
+void ScrollArea::setHorizontalScrollAmount(int hScroll)
+{
+    const int max = getHorizontalMaxScroll();
+
+    mHScroll = hScroll;
+
+    if (hScroll > max)
+        mHScroll = max;
+    else if (hScroll < 0)
+        mHScroll = 0;
+}
+
+void ScrollArea::setScrollAmount(const int hScroll, const int vScroll)
+{
+    setHorizontalScrollAmount(hScroll);
+    setVerticalScrollAmount(vScroll);
+}
+
+int ScrollArea::getHorizontalMaxScroll()
+{
+    checkPolicies();
+
+    const Widget *const content = getContent();
+    if (!content)
+        return 0;
+
+    const int value = content->getWidth() - getChildrenArea().width +
+        2 * content->getFrameSize();
+
+    if (value < 0)
+        return 0;
+
+    return value;
+}
+
+int ScrollArea::getVerticalMaxScroll()
+{
+    checkPolicies();
+
+    const Widget *const content = getContent();
+    if (!content)
+        return 0;
+
+    int value;
+
+    value = content->getHeight() - getChildrenArea().height +
+        2 * content->getFrameSize();
+
+    if (value < 0)
+        return 0;
+
+    return value;
+}
+
+void ScrollArea::setScrollbarWidth(const int width)
+{
+    if (width > 0)
+        mScrollbarWidth = width;
+}
+
+void ScrollArea::showWidgetPart(Widget *const widget, Rect area)
+{
+    const Widget *const content = getContent();
+    if (widget != content)
+        return;
+
+    BasicContainer::showWidgetPart(widget, area);
+
+    setHorizontalScrollAmount(content->getFrameSize()
+        - content->getX());
+    setVerticalScrollAmount(content->getFrameSize()
+        - content->getY());
+}
+
+Rect ScrollArea::getChildrenArea()
+{
+    const Rect area = Rect(0, 0,
+        mVBarVisible ? (getWidth() - mScrollbarWidth) : getWidth(),
+        mHBarVisible ? (getHeight() - mScrollbarWidth) : getHeight());
+
+    if (area.width < 0 || area.height < 0)
+        return Rect();
+
+    return area;
+}
+
+Widget *ScrollArea::getWidgetAt(int x, int y)
+{
+    if (getChildrenArea().isPointInRect(x, y))
+        return getContent();
+
+    return nullptr;
+}
+
+void ScrollArea::setWidth(int width)
+{
+    Widget::setWidth(width);
+    checkPolicies();
+}
+
+void ScrollArea::setHeight(int height)
+{
+    Widget::setHeight(height);
+    checkPolicies();
+}
+
+void ScrollArea::setDimension(const Rect& dimension)
+{
+    Widget::setDimension(dimension);
+    checkPolicies();
+}
+
+void ScrollArea::mouseWheelMovedUp(MouseEvent& mouseEvent)
+{
+    if (mouseEvent.isConsumed())
+        return;
+
+    setVerticalScrollAmount(getVerticalScrollAmount()
+        - getChildrenArea().height / 8);
+
+    mouseEvent.consume();
+}
+
+void ScrollArea::mouseWheelMovedDown(MouseEvent& mouseEvent)
+{
+    if (mouseEvent.isConsumed())
+        return;
+
+    setVerticalScrollAmount(getVerticalScrollAmount()
+        + getChildrenArea().height / 8);
+
+    mouseEvent.consume();
+}
+
+void ScrollArea::checkPolicies()
+{
+    const int w = getWidth();
+    const int h = getHeight();
+
+    mHBarVisible = false;
+    mVBarVisible = false;
+
+    const Widget *const content = getContent();
+    if (!content)
+    {
+        mHBarVisible = (mHPolicy == SHOW_ALWAYS);
+        mVBarVisible = (mVPolicy == SHOW_ALWAYS);
+        return;
+    }
+
+    if (mHPolicy == SHOW_AUTO &&
+        mVPolicy == SHOW_AUTO)
+    {
+        if (content->getWidth() <= w
+            && content->getHeight() <= h)
+        {
+            mHBarVisible = false;
+            mVBarVisible = false;
+        }
+
+        if (content->getWidth() > w)
+        {
+            mHBarVisible = true;
+        }
+
+        if ((content->getHeight() > h)
+            || (mHBarVisible && content->getHeight()
+            > h - mScrollbarWidth))
+        {
+            mVBarVisible = true;
+        }
+
+        if (mVBarVisible && content->getWidth() > w - mScrollbarWidth)
+            mHBarVisible = true;
+
+        return;
+    }
+
+    switch (mHPolicy)
+    {
+        case SHOW_NEVER:
+            mHBarVisible = false;
+            break;
+
+        case SHOW_ALWAYS:
+            mHBarVisible = true;
+            break;
+
+        case SHOW_AUTO:
+            if (mVPolicy == SHOW_NEVER)
+            {
+                mHBarVisible = (content->getWidth() > w);
+            }
+            else  // (mVPolicy == SHOW_ALWAYS)
+            {
+                mHBarVisible = (content->getWidth()
+                    > w - mScrollbarWidth);
+            }
+            break;
+
+        default:
+            break;
+    }
+
+    switch (mVPolicy)
+    {
+        case SHOW_NEVER:
+            mVBarVisible = false;
+            break;
+
+        case SHOW_ALWAYS:
+            mVBarVisible = true;
+            break;
+
+        case SHOW_AUTO:
+            if (mHPolicy == SHOW_NEVER)
+            {
+                mVBarVisible = (content->getHeight() > h);
+            }
+            else  // (mHPolicy == SHOW_ALWAYS)
+            {
+                mVBarVisible = (content->getHeight()
+                    > h - mScrollbarWidth);
+            }
+            break;
+        default:
+            break;
+    }
+}
diff --git a/src/gui/widgets/scrollarea.h b/src/gui/widgets/scrollarea.h
index 7d2b39a96..70abac6ef 100644
--- a/src/gui/widgets/scrollarea.h
+++ b/src/gui/widgets/scrollarea.h
@@ -20,11 +20,55 @@
  *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+/*      _______   __   __   __   ______   __   __   _______   __   __
+ *     / _____/\ / /\ / /\ / /\ / ____/\ / /\ / /\ / ___  /\ /  |\/ /\
+ *    / /\____\// / // / // / // /\___\// /_// / // /\_/ / // , |/ / /
+ *   / / /__   / / // / // / // / /    / ___  / // ___  / // /| ' / /
+ *  / /_// /\ / /_// / // / // /_/_   / / // / // /\_/ / // / |  / /
+ * /______/ //______/ //_/ //_____/\ /_/ //_/ //_/ //_/ //_/ /|_/ /
+ * \______\/ \______\/ \_\/ \_____\/ \_\/ \_\/ \_\/ \_\/ \_\/ \_\/
+ *
+ * Copyright (c) 2004 - 2008 Olof Naessén and Per Larsson
+ *
+ *
+ * Per Larsson a.k.a finalman
+ * Olof Naessén a.k.a jansem/yakslem
+ *
+ * Visit: http://guichan.sourceforge.net
+ *
+ * License: (BSD)
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name of Guichan nor the names of its contributors may
+ *    be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
+ * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
 #ifndef GUI_WIDGETS_SCROLLAREA_H
 #define GUI_WIDGETS_SCROLLAREA_H
 
-#include "gui/base/widgets/scrollarea.hpp"
+#include "gui/widgets/basiccontainer.h"
 
+#include "listeners/mouselistener.h"
 #include "listeners/widgetlistener.h"
 
 #include "localconsts.h"
@@ -41,11 +85,28 @@ class ImageCollection;
  *
  * \ingroup GUI
  */
-class ScrollArea final : public gcn::ScrollArea,
+class ScrollArea final : public BasicContainer,
+                         public MouseListener,
                          public WidgetListener
 {
     public:
         /**
+         * Scrollpolicies for the horizontal and vertical scrollbar.
+         * The policies are:
+         *
+         * SHOW_ALWAYS - Always show the scrollbars no matter what.
+         * SHOW_NEVER  - Never show the scrollbars no matter waht.
+         * SHOW_AUTO   - Show the scrollbars only when needed. That is if the
+         *               content grows larger then the ScrollArea.
+         */
+        enum ScrollPolicy
+        {
+            SHOW_ALWAYS = 0,
+            SHOW_NEVER,
+            SHOW_AUTO
+        };
+
+        /**
          * Constructor.
          *
          * @param content the initial content to show in the scroll area
@@ -135,6 +196,234 @@ class ScrollArea final : public gcn::ScrollArea,
 
         Rect getRightButtonDimension() const;
 
+        /**
+         * Sets the content.
+         *
+         * @param widget The content of the scroll area.
+         */
+        void setContent(Widget* widget);
+
+        /**
+         * Gets the content.
+         *
+         * @return The content of the scroll area.
+         */
+        Widget* getContent();
+
+        /**
+         * Sets the horizontal scrollbar policy. See enum with policies.
+         *
+         * @param hPolicy The policy for the horizontal scrollbar.
+         * @see getHorizontalScrollPolicy
+         */
+        void setHorizontalScrollPolicy(const ScrollPolicy hPolicy);
+
+        /**
+         * Gets the horizontal scrollbar policy. See enum with policies.
+         *
+         * @return The policy for the horizontal scrollbar policy.
+         * @see setHorizontalScrollPolicy, setScrollPolicy
+         */
+        ScrollPolicy getHorizontalScrollPolicy() const
+        { return mHPolicy; }
+
+        /**
+         * Sets the vertical scrollbar policy. See enum with policies.
+         *
+         * @param vPolicy The policy for the vertical scrollbar.
+         * @see getVerticalScrollPolicy
+         */
+        void setVerticalScrollPolicy(const ScrollPolicy vPolicy);
+
+        /**
+         * Gets the vertical scrollbar policy. See enum with policies.
+         *
+         * @return The policy for the vertical scrollbar.
+         * @see setVerticalScrollPolicy, setScrollPolicy
+         */
+        ScrollPolicy getVerticalScrollPolicy() const
+        { return mVPolicy; }
+
+        /**
+         * Sets the horizontal and vertical scrollbar policy.
+         *
+         * @param hPolicy The policy for the horizontal scrollbar.
+         * @param vPolicy The policy for the vertical scrollbar.
+         * @see getVerticalScrollPolicy, getHorizontalScrollPolicy
+         */
+        void setScrollPolicy(const ScrollPolicy hPolicy,
+                             const ScrollPolicy vPolicy);
+
+        /**
+         * Sets the amount to scroll vertically.
+         *
+         * @param vScroll The amount to scroll.
+         * @see getVerticalScrollAmount
+         */
+        void setVerticalScrollAmount(const int vScroll);
+
+        /**
+         * Gets the amount that is scrolled vertically.
+         *
+         * @return The scroll amount on vertical scroll.
+         * @see setVerticalScrollAmount, setScrollAmount
+         */
+        int getVerticalScrollAmount() const
+        { return mVScroll; }
+
+        /**
+         * Sets the amount to scroll horizontally.
+         *
+         * @param hScroll The amount to scroll.
+         * @see getHorizontalScrollAmount
+         */
+        void setHorizontalScrollAmount(int hScroll);
+
+        /**
+         * Gets the amount that is scrolled horizontally.
+         *
+         * @return The scroll amount on horizontal scroll.
+         * @see setHorizontalScrollAmount, setScrollAmount
+         */
+        int getHorizontalScrollAmount() const
+        { return mHScroll; }
+
+        /**
+         * Sets the amount to scroll horizontally and vertically.
+         *
+         * @param hScroll The amount to scroll on horizontal scroll.
+         * @param vScroll The amount to scroll on vertical scroll.
+         * @see getHorizontalScrollAmount, getVerticalScrollAmount
+         */
+        void setScrollAmount(const int hScroll, const int vScroll);
+
+        /**
+         * Gets the maximum amount of horizontal scroll.
+         *
+         * @return The horizontal max scroll.
+         */
+        int getHorizontalMaxScroll();
+
+        /**
+         * Gets the maximum amount of vertical scroll.
+         *
+         * @return The vertical max scroll.
+         */
+        int getVerticalMaxScroll();
+
+        /**
+         * Sets the width of the scroll bars.
+         *
+         * @param width The width of the scroll bars.
+         * @see getScrollbarWidth
+         */
+        void setScrollbarWidth(const int width);
+
+        /**
+         * Gets the width of the scroll bars.
+         *
+         * @return the width of the ScrollBar.
+         * @see setScrollbarWidth
+         */
+        int getScrollbarWidth() const
+        { return mScrollbarWidth; }
+
+        /**
+         * Sets the amount to scroll in pixels when the left scroll button is
+         * pushed.
+         *
+         * @param amount The amount to scroll in pixels. 
+         * @see getLeftButtonScrollAmount
+         */
+        void setLeftButtonScrollAmount(const int amount)
+        { mLeftButtonScrollAmount = amount; }
+
+        /**
+         * Sets the amount to scroll in pixels when the right scroll button is
+         * pushed.
+         *
+         * @param amount The amount to scroll in pixels.
+         * @see getRightButtonScrollAmount
+         */
+        void setRightButtonScrollAmount(const int amount)
+        { mRightButtonScrollAmount = amount; }
+
+        /**
+         * Sets the amount to scroll in pixels when the up scroll button is
+         * pushed.
+         *
+         * @param amount The amount to scroll in pixels.
+         * @see getUpButtonScrollAmount
+         */
+        void setUpButtonScrollAmount(const int amount)
+        { mUpButtonScrollAmount = amount; }
+
+        /**
+         * Sets the amount to scroll in pixels when the down scroll button is
+         * pushed.
+         *
+         * @param amount The amount to scroll in pixels.
+         * @see getDownButtonScrollAmount
+         */
+        void setDownButtonScrollAmount(const int amount)
+        { mDownButtonScrollAmount = amount; }
+
+        /**
+         * Gets the amount to scroll in pixels when the left scroll button is
+         * pushed.
+         *
+         * @return The amount to scroll in pixels.
+         * @see setLeftButtonScrollAmount
+         */
+        int getLeftButtonScrollAmount() const
+        { return mLeftButtonScrollAmount; }
+
+        /**
+         * Gets the amount to scroll in pixels when the right scroll button is
+         * pushed.
+         *
+         * @return The amount to scroll in pixels.
+         * @see setRightButtonScrollAmount
+         */
+        int getRightButtonScrollAmount() const
+        { return mRightButtonScrollAmount; }
+
+        /**
+         * Gets the amount to scroll in pixels when the up scroll button is
+         * pushed.
+         *
+         * @return The amount to scroll in pixels.
+         * @see setUpButtonScrollAmount
+         */
+        int getUpButtonScrollAmount() const
+        { return mUpButtonScrollAmount; }
+
+        /**
+         * Gets the amount to scroll in pixels when the down scroll button is
+         * pushed.
+         *
+         * @return The amount to scroll in pixels.
+         * @see setDownButtonScrollAmount
+         */
+        int getDownButtonScrollAmount() const
+        { return mDownButtonScrollAmount; }
+
+        void showWidgetPart(Widget *const widget, Rect area) override final;
+
+        Rect getChildrenArea() override final;
+
+        Widget *getWidgetAt(int x, int y) override final;
+
+        void setWidth(int width);
+
+        void setHeight(int height);
+
+        void setDimension(const Rect& dimension);
+
+        void mouseWheelMovedUp(MouseEvent& mouseEvent) override final;
+
+        void mouseWheelMovedDown(MouseEvent& mouseEvent) override final;
+
     protected:
         enum BUTTON_DIR
         {
@@ -150,12 +439,17 @@ class ScrollArea final : public gcn::ScrollArea,
          */
         void init(std::string skinName);
 
+        /**
+         * Checks the policies for the scroll bars.
+         */
+        void checkPolicies();
+
         void drawButton(Graphics *const graphics, const BUTTON_DIR dir);
         void calcButton(Graphics *const graphics, const BUTTON_DIR dir);
-        void drawVBar(Graphics *const graphics) override final;
-        void drawHBar(Graphics *const graphics) override final;
-        void drawVMarker(Graphics *const graphics) override final;
-        void drawHMarker(Graphics *const graphics) override final;
+        void drawVBar(Graphics *const graphics);
+        void drawHBar(Graphics *const graphics);
+        void drawVMarker(Graphics *const graphics);
+        void drawHMarker(Graphics *const graphics);
 
         void calcVBar(Graphics *const graphics);
         void calcHBar(Graphics *const graphics);
@@ -176,8 +470,111 @@ class ScrollArea final : public gcn::ScrollArea,
         static ImageRect hBackground;
         static Image *buttons[4][2];
 
-        int mX, mY;
-        int mClickX, mClickY;
+        /**
+         * Holds the vertical scroll amount.
+         */
+        int mVScroll;
+
+        /**
+         * Holds the horizontal scroll amount.
+         */
+        int mHScroll;
+
+        /**
+         * Holds the width of the scroll bars.
+         */
+        int mScrollbarWidth;
+
+        /**
+         * Holds the horizontal scroll bar policy.
+         */
+        ScrollPolicy mHPolicy;
+
+        /**
+         * Holds the vertical scroll bar policy.
+         */
+        ScrollPolicy mVPolicy;
+
+        /**
+         * True if the vertical scroll bar is visible, false otherwise.
+         */
+        bool mVBarVisible;
+
+        /**
+         * True if the horizontal scroll bar is visible, false otherwise.
+         */
+        bool mHBarVisible;
+
+        /**
+         * True if the up button is pressed, false otherwise.
+         */
+        bool mUpButtonPressed;
+
+        /**
+         * True if the down button is pressed, false otherwise.
+         */
+        bool mDownButtonPressed;
+
+        /**
+         * True if the left button is pressed, false otherwise.
+         */
+        bool mLeftButtonPressed;
+
+        /**
+         * True if the right button is pressed, false otherwise.
+         */
+        bool mRightButtonPressed;
+
+        /**
+         * Holds the up button scroll amount.
+         */
+        int mUpButtonScrollAmount;
+
+        /**
+         * Holds the down button scroll amount.
+         */
+        int mDownButtonScrollAmount;
+
+        /**
+         * Holds the left button scroll amount.
+         */
+        int mLeftButtonScrollAmount;
+
+        /**
+         * Holds the right button scroll amount.
+         */
+        int mRightButtonScrollAmount;
+
+        /**
+         * True if the vertical marked is dragged.
+         */
+        bool mIsVerticalMarkerDragged;
+
+        /**
+         * True if the horizontal marked is dragged.
+         */
+        bool mIsHorizontalMarkerDragged;
+
+        /**
+         * Holds the horizontal markers drag offset.
+         */
+        int mHorizontalMarkerDragOffset;
+
+        /**
+         * Holds the vertical markers drag offset.
+         */
+        int mVerticalMarkerDragOffset;
+
+        /**
+         * True if the scroll area should be opaque (that is
+         * display its background), false otherwise.
+         */
+        bool mOpaque;
+
+        int mX;
+        int mY;
+        int mClickX;
+        int mClickY;
         ImageCollection *mVertexes;
         ImageCollection *mVertexes2;
         int mXOffset;
diff --git a/src/gui/widgets/tabs/chattab.cpp b/src/gui/widgets/tabs/chattab.cpp
index fe979ae5a..8fe9d707b 100644
--- a/src/gui/widgets/tabs/chattab.cpp
+++ b/src/gui/widgets/tabs/chattab.cpp
@@ -72,8 +72,8 @@ ChatTab::ChatTab(const Widget2 *const widget,
         mTextOutput->setLinkHandler(chatWindow->mItemLinkHandler);
     mTextOutput->setAlwaysUpdate(false);
 
-    mScrollArea->setScrollPolicy(gcn::ScrollArea::SHOW_NEVER,
-                                 gcn::ScrollArea::SHOW_ALWAYS);
+    mScrollArea->setScrollPolicy(ScrollArea::SHOW_NEVER,
+        ScrollArea::SHOW_ALWAYS);
     mScrollArea->setScrollAmount(0, 1);
 
     if (chatWindow)
diff --git a/src/gui/widgets/tabs/setup_colors.cpp b/src/gui/widgets/tabs/setup_colors.cpp
index ac6bf2837..940d0cd3f 100644
--- a/src/gui/widgets/tabs/setup_colors.cpp
+++ b/src/gui/widgets/tabs/setup_colors.cpp
@@ -84,15 +84,15 @@ Setup_Colors::Setup_Colors(const Widget2 *const widget) :
     // TRANSLATORS: settings colors tab name
     setName(_("Colors"));
     mColorBox->addSelectionListener(this);
-    mScroll->setHorizontalScrollPolicy(gcn::ScrollArea::SHOW_NEVER);
+    mScroll->setHorizontalScrollPolicy(ScrollArea::SHOW_NEVER);
     mPreview->setOpaque(false);
 
     // don't do anything with links
     mPreview->setLinkHandler(nullptr);
 
     mPreviewBox->setHeight(20);
-    mPreviewBox->setScrollPolicy(gcn::ScrollArea::SHOW_NEVER,
-                                 gcn::ScrollArea::SHOW_NEVER);
+    mPreviewBox->setScrollPolicy(ScrollArea::SHOW_NEVER,
+        ScrollArea::SHOW_NEVER);
 
     mGradTypeSlider->setWidth(180);
     mGradTypeSlider->setActionEventId("slider_grad");
diff --git a/src/gui/widgets/tabs/setup_relations.cpp b/src/gui/widgets/tabs/setup_relations.cpp
index 1458ecd25..ca060477f 100644
--- a/src/gui/widgets/tabs/setup_relations.cpp
+++ b/src/gui/widgets/tabs/setup_relations.cpp
@@ -221,7 +221,7 @@ Setup_Relations::Setup_Relations(const Widget2 *const widget) :
 
     mPlayerTitleTable->setLinewiseSelection(true);
 
-    mPlayerScrollArea->setHorizontalScrollPolicy(gcn::ScrollArea::SHOW_NEVER);
+    mPlayerScrollArea->setHorizontalScrollPolicy(ScrollArea::SHOW_NEVER);
     mPlayerTable->setActionEventId(ACTION_TABLE);
     mPlayerTable->setLinewiseSelection(true);
     mPlayerTable->addActionListener(this);
diff --git a/src/gui/widgets/tabs/setup_video.cpp b/src/gui/widgets/tabs/setup_video.cpp
index f55dceaa4..d09704203 100644
--- a/src/gui/widgets/tabs/setup_video.cpp
+++ b/src/gui/widgets/tabs/setup_video.cpp
@@ -227,7 +227,7 @@ Setup_Video::Setup_Video(const Widget2 *const widget) :
     ScrollArea *const scrollArea = new ScrollArea(this, mModeList,
         true, "setup_video_background.xml");
     scrollArea->setWidth(150);
-    scrollArea->setHorizontalScrollPolicy(gcn::ScrollArea::SHOW_NEVER);
+    scrollArea->setHorizontalScrollPolicy(ScrollArea::SHOW_NEVER);
 
     mOpenGLDropDown->setSelected(renderToIndex[mOpenGLEnabled]);
 
diff --git a/src/gui/widgets/widget.h b/src/gui/widgets/widget.h
index 17f016c76..34f3647d5 100644
--- a/src/gui/widgets/widget.h
+++ b/src/gui/widgets/widget.h
@@ -959,7 +959,7 @@ class Widget : public Widget2
           * @param area The area to show.
           * @since 0.1.0
           */
-        virtual void showWidgetPart(Widget* widget A_UNUSED,
+        virtual void showWidgetPart(Widget *const widget A_UNUSED,
                                     Rect area A_UNUSED)
         { }