The XML-based resource system, known as XRC, allows user interface elements such as
dialogs, menu bars and toolbars, to be stored in text files and loaded into
the application at run-time. XRC files can also be compiled into binary XRS files or C++
-code (the former makes it possible to store all resources in since file and the latter
+code (the former makes it possible to store all resources in a single file and the latter
is useful when you want to embed the resources into the executable).
There are several advantages to using XRC resources.
\begin{itemize}\itemsep=0pt
\item Recompiling and linking an application is not necessary if the
resources change.
-\item If you use a dialog designers that generates C++ code, it can be hard
+\item If you use a dialog designer that generates C++ code, it can be hard
to reintegrate this into existing C++ code. Separation of resources and code
is a more elegant solution.
\item You can choose between different alternative resource files at run time, if necessary.
\begin{itemize}\itemsep=0pt
\item Include the appropriate headers: normally "wx/xrc/xmlres.h" will suffice;
\item If you are going to use \helpref{XRS files}{binaryresourcefiles}, install
-wxFileSystem ZIP handler first with {\tt wxFileSystem::AddHandler(new wxZipFSHandler);}
+wxFileSystem archive handler first with {\tt wxFileSystem::AddHandler(new wxArchiveFSHandler);}
\item call {\tt wxXmlResource::Get()->InitAllHandlers()} from your wxApp::OnInit function,
and then call {\tt wxXmlResource::Get()->Load("myfile.xrc")} to load the resource file;
\item to create a dialog from a resource, create it using the default constructor, and then
-load using for example {\tt wxXmlResource::Get()->LoadDialog(\&dlg, this, "dlg1");}
+load it using for example {\tt wxXmlResource::Get()->LoadDialog(\&dlg, this, "dlg1");}
\item set up event tables as usual but use the {\tt XRCID(str)} macro to translate from XRC string names
to a suitable integer identifier, for example {\tt EVT\_MENU(XRCID("quit"), MyFrame::OnQuit)}.
\end{itemize}
\item use \urlref{XRCed}{http://xrced.sf.net}, a wxPython-based
dialog editor that you can find in the {\tt wxPython/tools} subdirectory of the wxWidgets
CVS archive;
-\item use \urlref{Glade}{http://wxglade.sf.net}, a GUI designer written in wxPython. At the moment it can generate Python, C++ and XRC;
+\item use \urlref{wxGlade}{http://wxglade.sf.net}, a GUI designer written in wxPython. At the moment it can generate Python, C++ and XRC;
\item convert WIN32 RC files to XRC with the tool in {\tt contrib/utils/convertrc}.
\end{itemize}
-A complete list of third-party tools that write to XRC can be found at \urlref{www.wxwidgets.org/lnk\_tool.htm}{http://www.wxwidgets.org/lnk\_tool.in}.
+A complete list of third-party tools that write to XRC can be found at \urlref{www.wxwidgets.org/lnk\_tool.htm}{http://www.wxwidgets.org/lnk\_tool.htm}.
It is highly recommended that you use a resource editing tool, since it's fiddly writing
XRC files by hand.
\item -e (--extra-cpp-code): if used together with -c, generates C++ header file
containing class definitions for the windows defined by the XRC file (see special subsection)
\item -u (--uncompressed): do not compress XML files (C++ only)
-\item -g (--gettext): output .po catalog (to stdout, or a file if -o is used)
+\item -g (--gettext): output underscore-wrapped strings that poEdit or gettext can scan. Outputs to stdout, or a file if -o is used
\item -n (--function) <name>: specify C++ function name (use with -c)
\item -o (--output) <filename>: specify the output file, such as resource.xrs or resource.cpp
\item -l (--list-of-handlers) <filename>: output a list of necessary handlers to this file
XRS file is essentially a renamed ZIP archive which means that you can manipulate
it with standard ZIP tools. Note that if you are using XRS files, you have
-to initialize \helpref{wxFileSystem}{wxfilesystem} ZIP handler first! It is a simple
+to initialize the \helpref{wxFileSystem}{wxfilesystem} archive handler first! It is a simple
thing to do:
\begin{verbatim}
#include <wx/filesys.h>
- #include <wx/fs_zip.h>
+ #include <wx/fs_arc.h>
...
- wxFileSystem::AddHandler(new wxZipFSHandler);
+ wxFileSystem::AddHandler(new wxArchiveFSHandler);
\end{verbatim}
\subsection{Using embedded resources}\label{embeddedresource}
It is sometimes useful to embed resources in the executable itself instead
-of loading external file (e.g. when your app is small and consists only of one
+of loading an external file (e.g. when your app is small and consists only of one
exe file). XRC provides means to convert resources into regular C++ file that
can be compiled and included in the executable.
a command line switch). Use it to load the resource:
\begin{verbatim}
- extern void InitXMLResource(); // defined in generated file
+ extern void InitXmlResource(); // defined in generated file
...
wxXmlResource::Get()->InitAllHandlers();
InitXmlResource();
The generated window class can be used as basis for the full window class. The
class members which represent widgets may be accessed by name instead of using
{\tt XRCCTRL} every time you wish to reference them (note that they are {\tt protected} class members),
-though you must still use {\tt XRCID} to refer to widget ids in the event
+though you must still use {\tt XRCID} to refer to widget IDs in the event
table.
Example:
\end{verbatim}
+
+
\subsection{Adding new resource handlers}\label{newresourcehandlers}
-Coming soon.
+Adding a new resource handler is pretty easy.
+Typically, to add an handler for the {\tt MyControl} class, you'll want to create
+the {\tt xh\_mycontrol.h} {\tt xh\_mycontrol.cpp} files.
+
+The header needs to contains the {\tt MyControlXmlHandler} class definition:
+
+\begin{verbatim}
+class MyControlXmlHandler : public wxXmlResourceHandler
+{
+public:
+
+ // Constructor.
+ MyControlXmlHandler();
+
+ // Creates the control and returns a pointer to it.
+ virtual wxObject *DoCreateResource();
+
+ // Returns true if we know how to create a control for the given node.
+ virtual bool CanHandle(wxXmlNode *node);
+
+ // Register with wxWidgets' dynamic class subsystem.
+ DECLARE_DYNAMIC_CLASS(MyControlXmlHandler)
+};
+\end{verbatim}
+
+The implementation of your custom XML handler will typically look as:
+
+\begin{verbatim}
+// Register with wxWidgets' dynamic class subsystem.
+IMPLEMENT_DYNAMIC_CLASS(MyControlXmlHandler, wxXmlResourceHandler)
+
+MyControlXmlHandler::MyControlXmlHandler()
+{
+ // this call adds support for all wxWindows class styles
+ // (e.g. wxSIMPLE_BORDER, wxSUNKEN_BORDER, wxWS_EX_* etc etc)
+ AddWindowStyles();
+
+ // if MyControl class supports e.g. MYCONTROL_DEFAULT_STYLE
+ // you should use:
+ // XRC_ADD_STYLE(MYCONTROL_DEFAULT_STYLE);
+}
+
+wxObject *MyControlXmlHandler::DoCreateResource()
+{
+ // the following macro will init a pointer named "control"
+ // with a new instance of the MyControl class, but will NOT
+ // Create() it!
+ XRC_MAKE_INSTANCE(control, MyControl)
+
+ // this is the point where you'll typically need to do the most
+ // important changes: here the control is created and initialized.
+ // You'll want to use the wxXmlResourceHandler's getters to
+ // do most of your work.
+ // If e.g. the MyControl::Create function looks like:
+ //
+ // bool MyControl::Create(wxWindow *parent, int id,
+ // const wxBitmap &first, const wxPoint &posFirst,
+ // const wxBitmap &second, const wxPoint &posSecond,
+ // const wxString &theTitle, const wxFont &titleFont,
+ // const wxPoint &pos, const wxSize &size,
+ // long style = MYCONTROL_DEFAULT_STYLE,
+ // const wxString &name = wxT("MyControl"));
+ //
+ // then the XRC for your component should look like:
+ //
+ // <object class="MyControl" name="some_name">
+ // <first-bitmap>first.xpm</first-bitmap>
+ // <second-bitmap>text.xpm</second-bitmap>
+ // <first-pos>3,3</first-pos>
+ // <second-pos>4,4</second-pos>
+ // <the-title>a title</the-title>
+ // <title-font>
+ // <!-- the standard XRC tags for describing a font: <size>, <style>, <weight>, etc -->
+ // </title-font>
+ // <!-- XRC also accepts other usual tags for wxWindow-derived classes:
+ // like e.g. <name>, <style>, <size>, <position>, etc -->
+ // </object>
+ //
+ // and the code to read your custom tags from the XRC file is just:
+ control->Create(m_parentAsWindow, GetID(),
+ GetBitmap(wxT("first-bitmap")),
+ GetPosition(wxT("first-pos")),
+ GetBitmap(wxT("second-bitmap")),
+ GetPosition(wxT("second-pos")),
+ GetText(wxT("the-title")),
+ GetFont(wxT("title-font")),
+ GetPosition(), GetSize(), GetStyle(), GetName());
+
+ SetupWindow(control);
+
+ return control;
+}
+
+bool MyControlXmlHandler::CanHandle(wxXmlNode *node)
+{
+ // this function tells XRC system that this handler can parse
+ // the <object class="MyControl"> tags
+ return IsOfClass(node, wxT("MyControl"));
+}
+\end{verbatim}
+
+You may want to check the \helpref{wxXmlResourceHandler}{wxxmlresourcehandler} documentation
+to see how many built-in getters it contains. It's very easy to retrieve also complex structures
+out of XRC files using them.
projects / wxWidgets.git / blobdiff