sd/source/ui/slidesorter/inc/controller/SlsScrollBarManager.hxx

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  19
  20 #ifndef INCLUDED_SD_SOURCE_UI_SLIDESORTER_INC_CONTROLLER_SLSSCROLLBARMANAGER_HXX
  21 #define INCLUDED_SD_SOURCE_UI_SLIDESORTER_INC_CONTROLLER_SLSSCROLLBARMANAGER_HXX
  22
  23 #include <tools/link.hxx>
  24 #include <tools/gen.hxx>
  25 #include <vcl/timer.hxx>
  26 #include <vcl/scrbar.hxx>
  27 #include <vcl/vclptr.hxx>
  28
  29 #include <functional>
  30
  31 namespace sd { class Window; }
  32
  33 namespace sd { namespace slidesorter { class SlideSorter; } }
  34
  35 namespace sd { namespace slidesorter { namespace controller {
  36
  37 /** Manage the horizontal and vertical scroll bars.  Listen for events, set
  38     their sizes, place them in the window, determine their visibilities.
  39
  40     <p>Handle auto scrolling, i.e. the scrolling of the window when the
  41     mouse comes near the window border while dragging a selection.</p>
  42
  43     <p>In order to make the slide sorter be used in the task pane with its
  44     own vertical scrollbars the vertical scrollbar of the use of the slide
  45     sorter is optional.  When using it the available area in a window is
  46     used and the vertical scrollbar is displayed when that area is not large
  47     enough.  When the vertical scrollbar is not used then the available area
  48     is assumed to be modifiable.  In that case the PlaceScrollBars() method
  49     may return an area larger than the one given.<p>
  50 */
  51 class ScrollBarManager
  52 {
  53 public:
  54     /** Create a new scroll bar manager that manages three controls: the
  55         horizontal scroll bar, the vertical scroll bar, and the little
  56         window that fills the gap at the bottom right corner that is left
  57         between the two scroll bars.  Call LateInitialization() after
  58         constructing a new object.
  59     */
  60     ScrollBarManager (SlideSorter& rSlideSorter);
  61
  62     ~ScrollBarManager();
  63
  64     /** Register listeners at the scroll bars.  This method is called after
  65         startup of a new slide sorter object or after a reactivation of a
  66         slide sorter that for example is taken from a cache.
  67     */
  68     void Connect();
  69
  70     /** Remove listeners from the scroll bars.  This method is called when
  71         the slide sorter is destroyed or when it is suspended, e.g. put
  72         into a cache for later reuse.
  73     */
  74     void Disconnect();
  75
  76     /** Set up the scroll bar, i.e. thumb size and position.  Call this
  77         method when the content of the browser window changed, i.e. pages
  78         were inserted or deleted, the layout or the zoom factor has
  79         changed.
  80         @param bScrollToCurrentPosition
  81             When <TRUE/> then scroll the window to the new offset that is
  82             defined by the scroll bars.  Otherwise the new offset is simply
  83             set and the whole window is repainted.
  84     */
  85     void UpdateScrollBars (
  86         bool bScrollToCurrentPosition);
  87
  88     /** Place the scroll bars inside the given area.  When the available
  89         area is not large enough for the content to display the horizontal
  90         and/or vertical scroll bar is enabled.
  91         @param rAvailableArea
  92             The scroll bars will be placed inside this rectangle.  It is
  93             expected to be given in pixel relative to its parent.
  94         @param bIsHorizontalScrollBarAllowed
  95             Only when this flag is <TRUE/> the horizontal scroll may be
  96             displayed.
  97         @param bIsVerticalScrollBarAllowed
  98             Only when this flag is <TRUE/> the horizontal scroll may be
  99             displayed.
 100         @return
 101             Returns the space that remains after the scroll bars are
 102             placed.
 103     */
 104     ::tools::Rectangle PlaceScrollBars (
 105         const ::tools::Rectangle& rAvailableArea,
 106         const bool bIsHorizontalScrollBarAllowed,
 107         const bool bIsVerticalScrollBarAllowed);
 108
 109     /** Update the vertical and horizontal scroll bars so that the visible
 110         area has the given top and left values.
 111     */
 112     void SetTopLeft (const Point& rNewTopLeft);
 113
 114     /** Return the width of the vertical scroll bar, which--when
 115         shown--should be fixed in contrast to its height.
 116         @return
 117            Returns 0 when the vertical scroll bar is not shown or does not
 118            exist, otherwise its width in pixel is returned.
 119     */
 120     int GetVerticalScrollBarWidth() const;
 121
 122     /** Return the height of the horizontal scroll bar, which--when
 123         shown--should be fixed in contrast to its width.
 124         @return
 125            Returns 0 when the vertical scroll bar is not shown or does not
 126            exist, otherwise its height in pixel is returned.
 127     */
 128     int GetHorizontalScrollBarHeight() const;
 129
 130     /** Call this method to scroll a window while the mouse is in dragging a
 131         selection.  If the mouse is near the window border or is outside the
 132         window then scroll the window accordingly.
 133         @param rMouseWindowPosition
 134             The mouse position for which the scroll amount is calculated.
 135         @param rAutoScrollFunctor
 136             Every time when the window is scrolled then this functor is executed.
 137         @return
 138             When the window is scrolled then this method returns <TRUE/>.
 139             When the window is not changed then <FALSE/> is returned.
 140     */
 141     bool AutoScroll (
 142         const Point& rMouseWindowPosition,
 143         const ::std::function<void ()>& rAutoScrollFunctor);
 144
 145     void StopAutoScroll();
 146
 147     void clearAutoScrollFunctor();
 148
 149     enum Orientation { Orientation_Horizontal, Orientation_Vertical };
 150     /** Scroll the slide sorter by setting the thumbs of the scroll bars and
 151         by moving the content of the content window.
 152         @param eOrientation
 153             Defines whether to scroll horizontally or vertically.
 154         @param nDistance
 155             distance in slides.
 156     */
 157     void Scroll(
 158         const Orientation eOrientation,
 159         const sal_Int32 nDistance);
 160
 161 private:
 162     SlideSorter& mrSlideSorter;
 163
 164     /** The horizontal scroll bar.  Note that is used but not owned by
 165         objects of this class.  It is given to the constructor.
 166     */
 167     VclPtr<ScrollBar> mpHorizontalScrollBar;
 168
 169     /** The vertical scroll bar.  Note that is used but not owned by
 170         objects of this class.  It is given to the constructor.
 171     */
 172     VclPtr<ScrollBar> mpVerticalScrollBar;
 173
 174     /// Relative horizontal position of the visible area in the view.
 175     double mnHorizontalPosition;
 176     /// Relative vertical position of the visible area in the view.
 177     double mnVerticalPosition;
 178     /** The width and height of the border at the inside of the window which
 179         when entered while in drag mode leads to a scrolling of the window.
 180     */
 181     Size const maScrollBorder;
 182     /** The only task of this little window is to paint the little square at
 183         the bottom right corner left by the two scroll bars (when both are
 184         visible).
 185     */
 186     VclPtr<ScrollBarBox> mpScrollBarFiller;
 187
 188     /** The auto scroll timer is used for keep scrolling the window when the
 189         mouse reaches its border while dragging a selection.  When the mouse
 190         is not moved the timer issues events to keep scrolling.
 191     */
 192     Timer maAutoScrollTimer;
 193     Size maAutoScrollOffset;
 194     bool mbIsAutoScrollActive;
 195
 196     /** The content window is the one whose view port is controlled by the
 197         scroll bars.
 198     */
 199     VclPtr<sd::Window> mpContentWindow;
 200
 201     ::std::function<void ()> maAutoScrollFunctor;
 202
 203     void SetWindowOrigin (
 204         double nHorizontalPosition,
 205         double nVerticalPosition);
 206
 207     /** Determine the visibility of the scroll bars so that the window
 208         content is not clipped in any dimension without showing a scroll
 209         bar.
 210         @param rAvailableArea
 211             The area in which the scroll bars, the scroll bar filler, and
 212             the SlideSorterView will be placed.
 213         @return
 214             The area that is enclosed by the scroll bars is returned.  It
 215             will be filled with the SlideSorterView.
 216     */
 217     ::tools::Rectangle DetermineScrollBarVisibilities(
 218         const ::tools::Rectangle& rAvailableArea,
 219         const bool bIsHorizontalScrollBarAllowed,
 220         const bool bIsVerticalScrollBarAllowed);
 221
 222     /** Typically called by DetermineScrollBarVisibilities() this method
 223         tests a specific configuration of the two scroll bars being visible
 224         or hidden.
 225         @return
 226             When the window content can be shown with only being clipped in
 227             an orientation where the scroll bar would be shown then <TRUE/>
 228             is returned.
 229     */
 230     bool TestScrollBarVisibilities (
 231         bool bHorizontalScrollBarVisible,
 232         bool bVerticalScrollBarVisible,
 233         const ::tools::Rectangle& rAvailableArea);
 234
 235     void CalcAutoScrollOffset (const Point& rMouseWindowPosition);
 236     bool RepeatAutoScroll();
 237
 238     DECL_LINK(HorizontalScrollBarHandler, ScrollBar*, void);
 239     DECL_LINK(VerticalScrollBarHandler, ScrollBar*, void);
 240     DECL_LINK(AutoScrollTimeoutHandler, Timer *, void);
 241
 242     void PlaceHorizontalScrollBar (const ::tools::Rectangle& aArea);
 243     void PlaceVerticalScrollBar (const ::tools::Rectangle& aArea);
 244     void PlaceFiller (const ::tools::Rectangle& aArea);
 245 };
 246
 247 } } } // end of namespace ::sd::slidesorter::controller
 248
 249 #endif
 250
 251 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */