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

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
   2 /*
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   9  * This file incorporates work covered by the following license notice:
  10  *
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  15  *   License, Version 2.0 (the "License"); you may not use this file
  16  *   except in compliance with the License. You may obtain a copy of
  17  *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
  18  */
  19
  20 #pragma once
  21
  22 #include <tools/link.hxx>
  23 #include <tools/gen.hxx>
  24 #include <svtools/scrolladaptor.hxx>
  25 #include <vcl/timer.hxx>
  26 #include <vcl/vclptr.hxx>
  27
  28 #include <functional>
  29
  30 namespace sd { class Window; }
  31
  32 namespace sd::slidesorter { class SlideSorter; }
  33
  34 namespace sd::slidesorter::controller {
  35
  36 /** Manage the horizontal and vertical scroll bars.  Listen for events, set
  37     their sizes, place them in the window, determine their visibilities.
  38
  39     <p>Handle auto scrolling, i.e. the scrolling of the window when the
  40     mouse comes near the window border while dragging a selection.</p>
  41
  42     <p>In order to make the slide sorter be used in the task pane with its
  43     own vertical scrollbars the vertical scrollbar of the use of the slide
  44     sorter is optional.  When using it the available area in a window is
  45     used and the vertical scrollbar is displayed when that area is not large
  46     enough.  When the vertical scrollbar is not used then the available area
  47     is assumed to be modifiable.  In that case the PlaceScrollBars() method
  48     may return an area larger than the one given.<p>
  49 */
  50 class ScrollBarManager
  51 {
  52 public:
  53     /** Create a new scroll bar manager that manages three controls: the
  54         horizontal scroll bar, the vertical scroll bar, and the little
  55         window that fills the gap at the bottom right corner that is left
  56         between the two scroll bars.  Call LateInitialization() after
  57         constructing a new object.
  58     */
  59     ScrollBarManager (SlideSorter& rSlideSorter);
  60
  61     ~ScrollBarManager();
  62
  63     /** Register listeners at the scroll bars.  This method is called after
  64         startup of a new slide sorter object or after a reactivation of a
  65         slide sorter that for example is taken from a cache.
  66     */
  67     void Connect();
  68
  69     /** Remove listeners from the scroll bars.  This method is called when
  70         the slide sorter is destroyed or when it is suspended, e.g. put
  71         into a cache for later reuse.
  72     */
  73     void Disconnect();
  74
  75     /** Set up the scroll bar, i.e. thumb size and position.  Call this
  76         method when the content of the browser window changed, i.e. pages
  77         were inserted or deleted, the layout or the zoom factor has
  78         changed.
  79         @param bScrollToCurrentPosition
  80             When <TRUE/> then scroll the window to the new offset that is
  81             defined by the scroll bars.  Otherwise the new offset is simply
  82             set and the whole window is repainted.
  83     */
  84     void UpdateScrollBars (
  85         bool bScrollToCurrentPosition);
  86
  87     /** Place the scroll bars inside the given area.  When the available
  88         area is not large enough for the content to display the horizontal
  89         and/or vertical scroll bar is enabled.
  90         @param rAvailableArea
  91             The scroll bars will be placed inside this rectangle.  It is
  92             expected to be given in pixel relative to its parent.
  93         @param bIsHorizontalScrollBarAllowed
  94             Only when this flag is <TRUE/> the horizontal scroll may be
  95             displayed.
  96         @param bIsVerticalScrollBarAllowed
  97             Only when this flag is <TRUE/> the horizontal scroll may be
  98             displayed.
  99         @return
 100             Returns the space that remains after the scroll bars are
 101             placed.
 102     */
 103     ::tools::Rectangle PlaceScrollBars (
 104         const ::tools::Rectangle& rAvailableArea,
 105         const bool bIsHorizontalScrollBarAllowed,
 106         const bool bIsVerticalScrollBarAllowed);
 107
 108     /** Update the vertical and horizontal scroll bars so that the visible
 109         area has the given top and left values.
 110     */
 111     void SetTopLeft (const Point& rNewTopLeft);
 112
 113     /** Return the width of the vertical scroll bar, which--when
 114         shown--should be fixed in contrast to its height.
 115         @return
 116            Returns 0 when the vertical scroll bar is not shown or does not
 117            exist, otherwise its width in pixel is returned.
 118     */
 119     int GetVerticalScrollBarWidth() const;
 120
 121     /** Return the height of the horizontal scroll bar, which--when
 122         shown--should be fixed in contrast to its width.
 123         @return
 124            Returns 0 when the vertical scroll bar is not shown or does not
 125            exist, otherwise its height in pixel is returned.
 126     */
 127     int GetHorizontalScrollBarHeight() const;
 128
 129     /** Call this method to scroll a window while the mouse is in dragging a
 130         selection.  If the mouse is near the window border or is outside the
 131         window then scroll the window accordingly.
 132         @param rMouseWindowPosition
 133             The mouse position for which the scroll amount is calculated.
 134         @param rAutoScrollFunctor
 135             Every time when the window is scrolled then this functor is executed.
 136         @return
 137             When the window is scrolled then this method returns <TRUE/>.
 138             When the window is not changed then <FALSE/> is returned.
 139     */
 140     bool AutoScroll (
 141         const Point& rMouseWindowPosition,
 142         const ::std::function<void ()>& rAutoScrollFunctor);
 143
 144     void StopAutoScroll();
 145
 146     void clearAutoScrollFunctor();
 147
 148     enum Orientation { Orientation_Horizontal, Orientation_Vertical };
 149     /** Scroll the slide sorter by setting the thumbs of the scroll bars and
 150         by moving the content of the content window.
 151         @param eOrientation
 152             Defines whether to scroll horizontally or vertically.
 153         @param nDistance
 154             distance in slides.
 155     */
 156     void Scroll(
 157         const Orientation eOrientation,
 158         const sal_Int32 nDistance);
 159
 160 private:
 161     SlideSorter& mrSlideSorter;
 162
 163     /** The horizontal scroll bar.  Note that is used but not owned by
 164         objects of this class.  It is given to the constructor.
 165     */
 166     VclPtr<ScrollAdaptor> mpHorizontalScrollBar;
 167
 168     /** The vertical scroll bar.  Note that is used but not owned by
 169         objects of this class.  It is given to the constructor.
 170     */
 171     VclPtr<ScrollAdaptor> mpVerticalScrollBar;
 172
 173     /// Relative horizontal position of the visible area in the view.
 174     double mnHorizontalPosition;
 175     /// Relative vertical position of the visible area in the view.
 176     double mnVerticalPosition;
 177     /** The width and height of the border at the inside of the window which
 178         when entered while in drag mode leads to a scrolling of the window.
 179     */
 180     Size maScrollBorder;
 181
 182     /** The auto scroll timer is used for keep scrolling the window when the
 183         mouse reaches its border while dragging a selection.  When the mouse
 184         is not moved the timer issues events to keep scrolling.
 185     */
 186     Timer maAutoScrollTimer;
 187     Size maAutoScrollOffset;
 188     bool mbIsAutoScrollActive;
 189
 190     /** The content window is the one whose view port is controlled by the
 191         scroll bars.
 192     */
 193     VclPtr<sd::Window> mpContentWindow;
 194
 195     ::std::function<void ()> maAutoScrollFunctor;
 196
 197     void SetWindowOrigin (
 198         double nHorizontalPosition,
 199         double nVerticalPosition);
 200
 201     /** Determine the visibility of the scroll bars so that the window
 202         content is not clipped in any dimension without showing a scroll
 203         bar.
 204         @param rAvailableArea
 205             The area in which the scroll bars, the scroll bar filler, and
 206             the SlideSorterView will be placed.
 207         @return
 208             The area that is enclosed by the scroll bars is returned.  It
 209             will be filled with the SlideSorterView.
 210     */
 211     ::tools::Rectangle DetermineScrollBarVisibilities(
 212         const ::tools::Rectangle& rAvailableArea,
 213         const bool bIsHorizontalScrollBarAllowed,
 214         const bool bIsVerticalScrollBarAllowed);
 215
 216     /** Typically called by DetermineScrollBarVisibilities() this method
 217         tests a specific configuration of the two scroll bars being visible
 218         or hidden.
 219         @return
 220             When the window content can be shown with only being clipped in
 221             an orientation where the scroll bar would be shown then <TRUE/>
 222             is returned.
 223     */
 224     bool TestScrollBarVisibilities (
 225         bool bHorizontalScrollBarVisible,
 226         bool bVerticalScrollBarVisible,
 227         const ::tools::Rectangle& rAvailableArea);
 228
 229     void CalcAutoScrollOffset (const Point& rMouseWindowPosition);
 230     bool RepeatAutoScroll();
 231
 232     DECL_LINK(HorizontalScrollBarHandler, weld::Scrollbar&, void);
 233     DECL_LINK(VerticalScrollBarHandler, weld::Scrollbar&, void);
 234     DECL_LINK(AutoScrollTimeoutHandler, Timer *, void);
 235
 236     void PlaceHorizontalScrollBar (const ::tools::Rectangle& aArea);
 237     void PlaceVerticalScrollBar (const ::tools::Rectangle& aArea);
 238 };
 239
 240 } // end of namespace ::sd::slidesorter::controller
 241
 242 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */