-// ========================================================================
-// wxWindowCocoaScrollView
-// ========================================================================
-class wxWindowCocoaScrollView: protected wxCocoaNSView
-{
- DECLARE_NO_COPY_CLASS(wxWindowCocoaScrollView)
-public:
- wxWindowCocoaScrollView(wxWindow *owner);
- virtual ~wxWindowCocoaScrollView();
- inline WX_NSScrollView GetNSScrollView() { return m_cocoaNSScrollView; }
- void ClientSizeToSize(int &width, int &height);
- void DoGetClientSize(int *x, int *y) const;
- void Encapsulate();
- void Unencapsulate();
-
- // wxWindow calls this to do the work. Note that we don't have the refresh parameter
- // because wxWindow handles that itself.
- void SetScrollbar(int orientation, int position, int thumbSize, int range);
- int GetScrollPos(wxOrientation orient);
- void SetScrollPos(wxOrientation orient, int position);
- int GetScrollRange(wxOrientation orient);
- int GetScrollThumb(wxOrientation orient);
- void ScrollWindow(int dx, int dy, const wxRect*);
- void UpdateSizes();
-
- void _wx_doScroller(NSScroller *sender);
-
-protected:
- wxWindowCocoa *m_owner;
- WX_NSScrollView m_cocoaNSScrollView;
- virtual void Cocoa_FrameChanged(void);
- virtual void Cocoa_synthesizeMouseMoved(void) {}
- /*!
- Flag as to whether we're scrolling for a native view or a custom
- wxWindow. This controls the scrolling behavior. When providing
- scrolling for a native view we don't catch scroller action messages
- and thus don't send scroll events and we don't actually scroll the
- window when the application calls ScrollWindow.
-
- When providing scrolling for a custom wxWindow, we make the NSScroller
- send their action messages to us which we in turn package as wx window
- scrolling events. At this point, the window will not physically be
- scrolled. The application will most likely handle the event by calling
- ScrollWindow which will do the real scrolling. On the other hand,
- the application may instead not call ScrollWindow until some threshold
- is reached. This causes the window to only scroll in steps which is
- what, for instance, wxScrolledWindow does.
- */
- bool m_isNativeView;
- /*!
- The range as the application code wishes to see it. That is, the
- range from the last SetScrollbar call for the appropriate dimension.
- The horizontal dimension is the first [0] element and the vertical
- dimension the second [1] element.
-
- In wxMSW, a SCROLLINFO with nMin=0 and nMax=range-1 is used which
- gives exactly range possible positions so long as nPage (which is
- the thumb size) is less than or equal to 1.
- */
- int m_scrollRange[2];
- /*!
- The thumb size is intended to reflect the size of the visible portion
- of the scrolled document. As the document size increases, the thumb
- visible thumb size decreases. As document size decreases, the visible
- thumb size increases. However, the thumb size on wx is defined in
- terms of scroll units (which are effectively defined by the scroll
- range) and so increasing the number of scroll units to reflect increased
- document size will have the effect of decreasing the visible thumb
- size even though the number doesn't change.
-
- It's also important to note that subtracting the thumb size from the
- full range gives you the real range that can be used. Microsoft
- defines nPos (the current scrolling position) to be within the range
- from nMin to nMax - max(nPage - 1, 0). We know that wxMSW code always
- sets nMin = 0 and nMax = range -1. So let's algebraically reduce the
- definition of the maximum allowed position:
-
- Begin:
- = nMax - max(nPage - 1, 0)
- Substitute (range - 1) for nMax and thumbSize for nPage:
- = range - 1 - max(thumbSize - 1, 0)
- Add one inside the max conditional and subtract one outside of it:
- = range - 1 - (max(thumbSize - 1 + 1, 1) - 1)
- Reduce some constants:
- = range - 1 - (max(thumbSize, 1) - 1)
- Distribute the negative across the parenthesis:
- = range - 1 - max(thumbSize, 1) + 1
- Reduce the constants:
- = range - max(thumbSize, 1)
-
- Also keep in mind that thumbSize may never be greater than range but
- can be equal to it. Thus for the smallest possible thumbSize there
- are exactly range possible scroll positions (numbered from 0 to
- range - 1) and for the largest possible thumbSize there is exactly
- one possible scroll position (numbered 0).
- */
- int m_scrollThumb[2];
-
- /*!
- The origin of the virtual coordinate space expressed in terms of client
- coordinates. Starts at (0,0) and each call to ScrollWindow accumulates
- into it. Thus if the user scrolls the window right (thus causing the
- contents to move left with respect to the client origin, the
- application code (typically wxScrolledWindow) will be called with
- dx of -something, for example -20. This is added to m_virtualOrigin
- and thus m_virtualOrigin will be (-20,0) in this example.
- */
- wxPoint m_virtualOrigin;
-private:
- wxWindowCocoaScrollView();
-};
-