adding measuring contexts, streamlining printing code

[wxWidgets.git] / include / wx / app.h

/////////////////////////////////////////////////////////////////////////////
// Name:        wx/app.h
// Purpose:     wxAppBase class and macros used for declaration of wxApp
//              derived class in the user code
// Author:      Julian Smart
// Modified by:
// Created:     01/02/97
// RCS-ID:      $Id$
// Copyright:   (c) Julian Smart
// Licence:     wxWindows licence
/////////////////////////////////////////////////////////////////////////////

#ifndef _WX_APP_H_BASE_
#define _WX_APP_H_BASE_

// ----------------------------------------------------------------------------
// headers we have to include here
// ----------------------------------------------------------------------------

#include "wx/event.h"       // for the base class
#include "wx/build.h"
#include "wx/init.h"        // we must declare wxEntry()
#include "wx/intl.h"        // for wxLayoutDirection

class WXDLLIMPEXP_BASE wxAppConsole;
class WXDLLIMPEXP_BASE wxAppTraits;
class WXDLLIMPEXP_BASE wxCmdLineParser;
class WXDLLIMPEXP_BASE wxLog;
class WXDLLIMPEXP_BASE wxMessageOutput;

#if wxUSE_GUI
    class WXDLLEXPORT wxEventLoop;
    struct WXDLLIMPEXP_CORE wxVideoMode;
#endif

// ----------------------------------------------------------------------------
// typedefs
// ----------------------------------------------------------------------------

// the type of the function used to create a wxApp object on program start up
typedef wxAppConsole* (*wxAppInitializerFunction)();

// ----------------------------------------------------------------------------
// constants
// ----------------------------------------------------------------------------

enum
{
    wxPRINT_WINDOWS = 1,
    wxPRINT_POSTSCRIPT = 2
};

// ----------------------------------------------------------------------------
// wxAppConsole: wxApp for non-GUI applications
// ----------------------------------------------------------------------------

class WXDLLIMPEXP_BASE wxAppConsole : public wxEvtHandler
{
public:
    // ctor and dtor
    wxAppConsole();
    virtual ~wxAppConsole();


    // the virtual functions which may/must be overridden in the derived class
    // -----------------------------------------------------------------------

    // This is the very first function called for a newly created wxApp object,
    // it is used by the library to do the global initialization. If, for some
    // reason, you must override it (instead of just overriding OnInit(), as
    // usual, for app-specific initializations), do not forget to call the base
    // class version!
    virtual bool Initialize(int& argc, wxChar **argv);

    // This gives wxCocoa a chance to call OnInit() with a memory pool in place
    virtual bool CallOnInit() { return OnInit(); }

    // Called before OnRun(), this is a good place to do initialization -- if
    // anything fails, return false from here to prevent the program from
    // continuing. The command line is normally parsed here, call the base
    // class OnInit() to do it.
    virtual bool OnInit();

    // this is here only temporary hopefully (FIXME)
    virtual bool OnInitGui() { return true; }

    // This is the replacement for the normal main(): all program work should
    // be done here. When OnRun() returns, the programs starts shutting down.
    virtual int OnRun() = 0;

    // This is only called if OnInit() returned true so it's a good place to do
    // any cleanup matching the initializations done there.
    virtual int OnExit();

    // This is the very last function called on wxApp object before it is
    // destroyed. If you override it (instead of overriding OnExit() as usual)
    // do not forget to call the base class version!
    virtual void CleanUp();

    // Called when a fatal exception occurs, this function should take care not
    // to do anything which might provoke a nested exception! It may be
    // overridden if you wish to react somehow in non-default way (core dump
    // under Unix, application crash under Windows) to fatal program errors,
    // however extreme care should be taken if you don't want this function to
    // crash.
    virtual void OnFatalException() { }

    // Called from wxExit() function, should terminate the application a.s.a.p.
    virtual void Exit();


    // application info: name, description, vendor
    // -------------------------------------------

    // NB: all these should be set by the application itself, there are no
    //     reasonable default except for the application name which is taken to
    //     be argv[0]

        // set/get the application name
    wxString GetAppName() const
    {
        return m_appName.empty() ? m_className : m_appName;
    }
    void SetAppName(const wxString& name) { m_appName = name; }

        // set/get the app class name
    wxString GetClassName() const { return m_className; }
    void SetClassName(const wxString& name) { m_className = name; }

        // set/get the vendor name
    const wxString& GetVendorName() const { return m_vendorName; }
    void SetVendorName(const wxString& name) { m_vendorName = name; }


    // cmd line parsing stuff
    // ----------------------

    // all of these methods may be overridden in the derived class to
    // customize the command line parsing (by default only a few standard
    // options are handled)
    //
    // you also need to call wxApp::OnInit() from YourApp::OnInit() for all
    // this to work

#if wxUSE_CMDLINE_PARSER
    // this one is called from OnInit() to add all supported options
    // to the given parser (don't forget to call the base class version if you
    // override it!)
    virtual void OnInitCmdLine(wxCmdLineParser& parser);

    // called after successfully parsing the command line, return true
    // to continue and false to exit (don't forget to call the base class
    // version if you override it!)
    virtual bool OnCmdLineParsed(wxCmdLineParser& parser);

    // called if "--help" option was specified, return true to continue
    // and false to exit
    virtual bool OnCmdLineHelp(wxCmdLineParser& parser);

    // called if incorrect command line options were given, return
    // false to abort and true to continue
    virtual bool OnCmdLineError(wxCmdLineParser& parser);
#endif // wxUSE_CMDLINE_PARSER


    // miscellaneous customization functions
    // -------------------------------------

    // create the app traits object to which we delegate for everything which
    // either should be configurable by the user (then he can change the
    // default behaviour simply by overriding CreateTraits() and returning his
    // own traits object) or which is GUI/console dependent as then wxAppTraits