fixed crash in OnSize() handler

[wxWidgets.git] / docs / latex / wx / scrolwin.tex

diff --git a/docs/latex/wx/scrolwin.tex b/docs/latex/wx/scrolwin.tex
index 5b53e8aa360735373bd29bc2631e2b486c7f1827..0129bee0436aa3dfd7a1094851202939f83372b4 100644 (file)
--- a/docs/latex/wx/scrolwin.tex
+++ b/docs/latex/wx/scrolwin.tex
@@ -6,7 +6,7 @@ scroll positions, thumb sizes and ranges according to the area in view.
 
 As with all windows, an application can draw onto a wxScrolledWindow using a \helpref{device context}{dcoverview}.
 
 
 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}).
 
 or overriding the \helpref{OnDraw}{wxscrolledwindowondraw} function, which is passed
 a pre-scrolled device context (prepared by \helpref{PrepareDC}{wxscrolledwindowpreparedc}).
 


@@ -14,8 +14,23 @@ If you don't wish to calculate your own scrolling, you must call PrepareDC when
 within OnDraw, to set the device origin for the device context according to the current
 scroll position.
 
 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 will 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}
 
 \wxheading{Derived from}
 

+\helpref{wxPanel}{wxpanel}\\

 \helpref{wxWindow}{wxwindow}\\
 \helpref{wxEvtHandler}{wxevthandler}\\
 \helpref{wxObject}{wxobject}
 \helpref{wxWindow}{wxwindow}\\
 \helpref{wxEvtHandler}{wxevthandler}\\
 \helpref{wxObject}{wxobject}


@@ -86,6 +101,52 @@ specify how big the virtual window size should be.
 
 Destructor.
 
 
 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, 10, \&xx, \&yy) will return 0 in yy.
+
+\wxheading{See also}
+
+\helpref{CalcUnscrolledPosition}{wxscrolledwindowcalcunscrolledposition}
+
+\pythonnote{The wxPython version of this methods accepts only two
+parameters and returns xx and yy as a tuple of values.}
+
+\perlnote{In wxPerl this method takes two parameters and returns a
+2-element list {\tt ( xx, yy )}.}
+
+\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, 0, \&xx, \&yy) will return 10 in yy.
+
+\wxheading{See also}
+
+\helpref{CalcScrolledPosition}{wxscrolledwindowcalcscrolledposition}
+
+\pythonnote{The wxPython version of this methods accepts only two
+parameters and returns xx and yy as a tuple of values.}
+
+\perlnote{In wxPerl this method takes two parameters and returns a
+2-element list {\tt ( xx, yy )}.}
+

 \membersection{wxScrolledWindow::Create}\label{wxscrolledwindowcreate}
 
 \func{bool}{Create}{\param{wxWindow*}{ parent}, \param{wxWindowID }{id = -1},\rtfsp
 \membersection{wxScrolledWindow::Create}\label{wxscrolledwindowcreate}
 
 \func{bool}{Create}{\param{wxWindow*}{ parent}, \param{wxWindowID }{id = -1},\rtfsp


@@ -104,7 +165,9 @@ Enable or disable physical scrolling in the given direction. Physical
 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 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}
 
 
 \wxheading{Parameters}
 


@@ -136,6 +199,12 @@ scrolling in that direction.
 \helpref{wxScrolledWindow::SetScrollbars}{wxscrolledwindowsetscrollbars},\rtfsp
 \helpref{wxScrolledWindow::GetVirtualSize}{wxscrolledwindowgetvirtualsize}
 
 \helpref{wxScrolledWindow::SetScrollbars}{wxscrolledwindowsetscrollbars},\rtfsp
 \helpref{wxScrolledWindow::GetVirtualSize}{wxscrolledwindowgetvirtualsize}
 

+\pythonnote{The wxPython version of this methods accepts no
+parameters and returns a tuple of values for xUnit and yUnit.}
+
+\perlnote{In wxPerl this method takes no parameters and returns a
+2-element list {\tt ( xUnit, yUnit )}.}
+

 \membersection{wxScrolledWindow::GetVirtualSize}\label{wxscrolledwindowgetvirtualsize}
 
 \constfunc{void}{GetVirtualSize}{\param{int* }{x}, \param{int* }{y}}
 \membersection{wxScrolledWindow::GetVirtualSize}\label{wxscrolledwindowgetvirtualsize}
 
 \constfunc{void}{GetVirtualSize}{\param{int* }{x}, \param{int* }{y}}


@@ -160,11 +229,17 @@ to translate these units to logical units.
 \helpref{wxScrolledWindow::SetScrollbars}{wxscrolledwindowsetscrollbars},\rtfsp
 \helpref{wxScrolledWindow::GetScrollPixelsPerUnit}{wxscrolledwindowgetscrollpixelsperunit}
 
 \helpref{wxScrolledWindow::SetScrollbars}{wxscrolledwindowsetscrollbars},\rtfsp
 \helpref{wxScrolledWindow::GetScrollPixelsPerUnit}{wxscrolledwindowgetscrollpixelsperunit}
 

+\pythonnote{The wxPython version of this methods accepts no
+parameters and returns a tuple of values for x and y.}
+
+\perlnote{In wxPerl this method takes no parameters and returns a
+2-element list {\tt ( x, y )}.}
+

 \membersection{wxScrolledWindow::IsRetained}\label{wxscrolledwindowisretained}
 
 \constfunc{bool}{IsRetained}{\void}
 
 \membersection{wxScrolledWindow::IsRetained}\label{wxscrolledwindowisretained}
 
 \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}
 
 
 \membersection{wxScrolledWindow::PrepareDC}\label{wxscrolledwindowpreparedc}
 


@@ -173,7 +248,7 @@ TRUE if the window has a backing bitmap.
 Call this function to prepare the device context for drawing a scrolled image. It
 sets the device origin according to the current scroll position.
 
 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
 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


@@ -201,45 +276,13 @@ void MyWindow::OnEvent(wxMouseEvent& event)
 
 \func{virtual void}{OnDraw}{\param{wxDC\& }{dc}}
 
 
 \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}.
+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}.

 
 

-\membersection{wxScrolledWindow::OnPaint}\label{wxscrolledwindowonpaint}
-
-\func{void}{OnPaint}{\param{wxPaintEvent\& }{event}}
-
-Sent to the window when the window must be refreshed.
-
-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}
 
 
 \membersection{wxScrolledWindow::Scroll}\label{wxscrolledwindowscroll}
 


@@ -269,7 +312,8 @@ that direction).
 
 \func{void}{SetScrollbars}{\param{int}{ pixelsPerUnitX}, \param{int}{ pixelsPerUnitY},\rtfsp
 \param{int}{ noUnitsX}, \param{int}{ noUnitsY},\rtfsp
 
 \func{void}{SetScrollbars}{\param{int}{ pixelsPerUnitX}, \param{int}{ pixelsPerUnitY},\rtfsp
 \param{int}{ noUnitsX}, \param{int}{ noUnitsY},\rtfsp

-\param{int }{xPos = 0}, \param{int}{ yPos = 0}}
+\param{int }{xPos = 0}, \param{int}{ yPos = 0},\rtfsp
+\param{bool }{noRefresh = FALSE}}

 
 Sets up vertical and/or horizontal scrollbars.
 
 
 Sets up vertical and/or horizontal scrollbars.
 


@@ -287,6 +331,8 @@ Sets up vertical and/or horizontal scrollbars.
 
 \docparam{yPos}{Position to initialize the scrollbars in the vertical direction, in scroll units.}
 
 
 \docparam{yPos}{Position to initialize the scrollbars in the vertical direction, in scroll units.}
 

+\docparam{noRefresh}{Will not refresh window if TRUE.}
+

 \wxheading{Remarks}
 
 The first pair of parameters give the number of pixels per `scroll step', i.e. amount
 \wxheading{Remarks}
 
 The first pair of parameters give the number of pixels per `scroll step', i.e. amount


@@ -312,9 +358,16 @@ scroll steps may be variable according to the position in the document, it will
 necessary to derive a new class from wxWindow, overriding {\bf OnSize} and
 adjusting the scrollbars appropriately.
 
 necessary to derive a new class from wxWindow, overriding {\bf OnSize} and
 adjusting the scrollbars appropriately.
 

-\membersection{wxScrolledWindow::ViewStart}\label{wxscrolledwindowviewstart}
+\membersection{wxScrolledWindow::SetTargetWindow}\label{wxscrolledwindowsettargetwindow}

 
 

-\constfunc{void}{ViewStart}{\param{int* }{x}, \param{int* }{ y}}
+\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::GetViewStart}\label{wxscrolledwindowgetviewstart}
+
+\constfunc{void}{GetViewStart}{\param{int* }{x}, \param{int* }{ y}}

 
 Get the position at which the visible portion of the window starts.
 
 
 Get the position at which the visible portion of the window starts.
 


@@ -337,3 +390,9 @@ by the number of pixels per scroll increment.
 
 \helpref{wxScrolledWindow::SetScrollbars}{wxscrolledwindowsetscrollbars}
 
 
 \helpref{wxScrolledWindow::SetScrollbars}{wxscrolledwindowsetscrollbars}
 

+\pythonnote{The wxPython version of this methods accepts no
+parameters and returns a tuple of values for x and y.}
+
+\perlnote{In wxPerl this method takes no parameters and returns a
+2-element list {\tt ( x, y )}.}
+