As with all windows, an application can draw onto a wxScrolledWindow using a \helpref{device context}{dcoverview}.
-You have the option of handling the \helpref{OnPaint}{wxscrolledwindowonpaint} handler
+You have the option of handling the OnPaint handler
or overriding the \helpref{OnDraw}{wxscrolledwindowondraw} function, which is passed
a pre-scrolled device context (prepared by \helpref{PrepareDC}{wxscrolledwindowpreparedc}).
within OnDraw, to set the device origin for the device context according to the current
scroll position.
+A wxScrolledWindow will normally scroll itself and therefore its child windows as well. It
+might however be desired to scroll a different window than itself: e.g. when designing a
+spreadsheet, you'll normally only have to scroll the (usually white) cell area, whereas the
+(usually grey) label area will scroll very differently. For this special purpose, you can
+call \helpref{SetTargetWindow}{wxscrolledwindowsettargetwindow} which means that pressing
+the scrollbars will scroll a different window.
+
+Note that the underlying system knows nothing about scrolling coordinates, so that all system
+functions (mouse events, expose events, refresh calls etc) as well as the position of subwindows
+are relative to the "physical" origin of the scrolled window. If the user insert a child window at
+position (10,10) and scrolls the window down 100 pixels (moving the child window out of the visible
+area), the child window will report a position of (10,-90).
+
+
\wxheading{Derived from}
+\helpref{wxPanel}{wxpanel}\\
\helpref{wxWindow}{wxwindow}\\
\helpref{wxEvtHandler}{wxevthandler}\\
\helpref{wxObject}{wxobject}
Destructor.
+\membersection{wxScrolledWindow::CalcScrolledPosition}\label{wxscrolledwindowcalcscrolledposition}
+
+\constfunc{void}{CalcScrolledPosition}{
+ \param{int }{x},
+ \param{int }{y},
+ \param{int *}{xx}
+ \param{int *}{yy}}
+
+Translates the logical coordinates to the device ones. For example, if a window is
+scrolled 10 pixels to the bottom, the device coordinates of the origin are (0, 0)
+(as always), but the logical coordinates are (0, 10) and so the call to
+CalcScrolledPosition(0, 0, \&xx, \&yy) will return 10 in yy.
+
+\wxheading{See also}
+
+\helpref{CalcUnscrolledPosition}{wxscrolledwindowcalcunscrolledposition}
+
+\membersection{wxScrolledWindow::CalcUnscrolledPosition}\label{wxscrolledwindowcalcunscrolledposition}
+
+\constfunc{void}{CalcUnscrolledPosition}{
+ \param{int }{x},
+ \param{int }{y},
+ \param{int *}{xx}
+ \param{int *}{yy}}
+
+Translates the device coordinates to the logical ones. For example, if a window is
+scrolled 10 pixels to the bottom, the device coordinates of the origin are (0, 0)
+(as always), but the logical coordinates are (0, 10) and so the call to
+CalcUnscrolledPosition(0, 10, \&xx, \&yy) will return 0 in yy.
+
+\wxheading{See also}
+
+\helpref{CalcScrolledPosition}{wxscrolledwindowcalcscrolledposition}
+
\membersection{wxScrolledWindow::Create}\label{wxscrolledwindowcreate}
\func{bool}{Create}{\param{wxWindow*}{ parent}, \param{wxWindowID }{id = -1},\rtfsp
scrolling is the physical transfer of bits up or down the
screen when a scroll event occurs. If the application scrolls by a
variable amount (e.g. if there are different font sizes) then physical
-scrolling will not work, and you should switch it off.
+scrolling will not work, and you should switch it off. Note that you
+will have to reposition child windows yourself, if physical scrolling
+is disabled.
\wxheading{Parameters}
\constfunc{bool}{IsRetained}{\void}
-TRUE if the window has a backing bitmap.
+Motif only: TRUE if the window has a backing bitmap.
\membersection{wxScrolledWindow::PrepareDC}\label{wxscrolledwindowpreparedc}
Call this function to prepare the device context for drawing a scrolled image. It
sets the device origin according to the current scroll position.
-PrepareDC is called automatically within the default \helpref{wxScrolledWindow::OnPaint}{wxscrolledwindowonpaint} event
+PrepareDC is called automatically within the default wxScrolledWindow::OnPaint event
handler, so your \helpref{wxScrolledWindow::OnDraw}{wxscrolledwindowondraw} override
will be passed a 'pre-scrolled' device context. However, if you wish to draw from
outside of OnDraw (via OnPaint), or you wish to implement OnPaint yourself, you must
\func{virtual void}{OnDraw}{\param{wxDC\& }{dc}}
-Called by the default \helpref{wxScrolledWindow::OnPaint}{wxscrolledwindowonpaint} implementation
-to allow the application to define painting behaviour without having to worry about
-calling \helpref{wxScrolledWindow::PrepareDC}{wxscrolledwindowpreparedc}.
-
-\membersection{wxScrolledWindow::OnPaint}\label{wxscrolledwindowonpaint}
-
-\func{void}{OnPaint}{\param{wxPaintEvent\& }{event}}
-
-Sent to the window when the window must be refreshed.
+Called by the default paint event handler to allow the application to define
+painting behaviour without having to worry about calling
+\helpref{wxScrolledWindow::PrepareDC}{wxscrolledwindowpreparedc}.
-For more details, see \helpref{wxWindow::OnPaint}{wxwindowonpaint}.
-
-The default implementation for wxScrolledWindow's OnPaint handler is simply:
-
-\begin{verbatim}
-void wxScrolledWindow::OnPaint(wxPaintEvent& event)
-{
- wxPaintDC dc(this);
- PrepareDC(dc);
-
- OnDraw(dc);
-}
-\end{verbatim}
-
-\membersection{wxScrolledWindow::OnScroll}\label{wxscrolledwindowonscroll}
-
-\func{void}{OnScroll}{\param{wxScrollEvent\& }{event}}
-
-Override this function to intercept scroll events. This
-member function implements the default scroll behaviour. If
-you do not call the default function, you will have to manage
-all scrolling behaviour including drawing the window contents
-at an appropriate position relative to the scrollbars.
-
-For more details, see \helpref{wxWindow::OnScroll}{wxwindowonscroll}.
-
-\wxheading{See also}
-
-\helpref{wxScrollEvent}{wxscrollevent}
+Instead of overriding this function you may also just process the paint event
+in the derived class as usual, but then you will have to call PrepareDC()
+yourself.
\membersection{wxScrolledWindow::Scroll}\label{wxscrolledwindowscroll}
necessary to derive a new class from wxWindow, overriding {\bf OnSize} and
adjusting the scrollbars appropriately.
+\membersection{wxScrolledWindow::SetTargetWindow}\label{wxscrolledwindowsettargetwindow}
+
+\func{void}{SetTargetWindow}{\param{wxWindow* }{window}}
+
+Call this function to tell wxScrolledWindow to perform the actually scrolling on
+a different window (not on itself).
+
\membersection{wxScrolledWindow::ViewStart}\label{wxscrolledwindowviewstart}
\constfunc{void}{ViewStart}{\param{int* }{x}, \param{int* }{ y}}
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