samples/html/virtual/virtual.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        virtual.cpp
   3 // Purpose:     wxHtml sample: demonstrates virtual file systems feature
   4 // Author:      ?
   5 // Modified by:
   6 // Created:     ?
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) wxWidgets team
   9 // Licence:     wxWindows licence
  10 /////////////////////////////////////////////////////////////////////////////
  11
  12 // For compilers that support precompilation, includes "wx/wx.h".
  13 #include "wx/wxprec.h"
  14
  15 #ifdef __BORLANDC__
  16     #pragma hdrstop
  17 #endif
  18
  19 // for all others, include the necessary headers (this file is usually all you
  20 // need because it includes almost all "standard" wxWidgets headers
  21 #ifndef WX_PRECOMP
  22     #include "wx/wx.h"
  23 #endif
  24
  25 #include "wx/html/htmlwin.h"
  26
  27 #ifndef __WXMSW__
  28     #include "../../sample.xpm"
  29 #endif
  30
  31 // new handler class:
  32
  33 #include "wx/wfstream.h"
  34 #include "wx/mstream.h"
  35
  36
  37 // ----------------------------------------------------------------------------
  38 // MyVFS
  39 // ----------------------------------------------------------------------------
  40
  41 class MyVFS : public wxFileSystemHandler
  42 {
  43 public:
  44     MyVFS() : wxFileSystemHandler() {}
  45
  46     wxFSFile* OpenFile(wxFileSystem& fs, const wxString& location);
  47     bool CanOpen(const wxString& location);
  48 };
  49
  50 bool MyVFS::CanOpen(const wxString& location)
  51 {
  52     return (GetProtocol(location) == wxT("myVFS"));
  53 }
  54
  55 wxFSFile* MyVFS::OpenFile(wxFileSystem& WXUNUSED(fs), const wxString& location)
  56 {
  57     wxFSFile *f;
  58     wxInputStream *str;
  59     static char buf[1024];
  60     const wxWX2MBbuf loc = location.ToAscii();
  61
  62     sprintf(buf, "<html><body><h2><i>You're in Node <u>%s</u></i></h2><p>"
  63                 "Where do you want to go?<br><blockquote>"
  64                 "<a href=\"%s-1\">sub-1</a><br>"
  65                 "<a href=\"%s-2\">sub-2</a><br>"
  66                 "<a href=\"%s-3\">sub-3</a><br>"
  67                 "</blockquote></body></html>",
  68                 (const char*)loc, (const char*)loc, (const char*)loc,
  69                 (const char*)loc);
  70
  71     // NB: There's a terrible hack involved: we fill 'buf' with new data every
  72     //     time this method is called and return new wxMemoryInputStream pointing to it.
  73     //     This won't work as soon as there are 2+ myVFS files opened. Fortunately,
  74     //     this won't happen because wxHTML keeps only one "page" file opened at the
  75     //     time.
  76     str = new wxMemoryInputStream(buf, strlen(buf));
  77     f = new wxFSFile(str, location, wxT("text/html"), wxEmptyString, wxDateTime::Today());
  78
  79     return f;
  80 }
  81
  82
  83
  84 // ----------------------------------------------------------------------------
  85 // private classes
  86 // ----------------------------------------------------------------------------
  87
  88 // Define a new application type, each program should derive a class from wxApp
  89 class MyApp : public wxApp
  90 {
  91 public:
  92     // override base class virtuals
  93     // ----------------------------
  94
  95     // this one is called on application startup and is a good place for the app
  96     // initialization (doing it here and not in the ctor allows to have an error
  97     // return: if OnInit() returns false, the application terminates)
  98     virtual bool OnInit();
  99 };
 100
 101 // Define a new frame type: this is going to be our main frame
 102 class MyFrame : public wxFrame
 103 {
 104 public:
 105     // ctor(s)
 106     MyFrame(const wxString& title, const wxPoint& pos, const wxSize& size);
 107
 108     // event handlers (these functions should _not_ be virtual)
 109     void OnQuit(wxCommandEvent& event);
 110     void OnBack(wxCommandEvent& event);
 111     void OnForward(wxCommandEvent& event);
 112
 113 private:
 114     // any class wishing to process wxWidgets events must use this macro
 115     DECLARE_EVENT_TABLE()
 116 };
 117
 118 // ----------------------------------------------------------------------------
 119 // constants
 120 // ----------------------------------------------------------------------------
 121
 122 // IDs for the controls and the menu commands
 123 enum
 124 {
 125         // menu items
 126     Minimal_Quit = 1,
 127     Minimal_Back,
 128     Minimal_Forward,
 129
 130         // controls start here (the numbers are, of course, arbitrary)
 131     Minimal_Text = 1000
 132 };
 133
 134 // ----------------------------------------------------------------------------
 135 // event tables and other macros for wxWidgets
 136 // ----------------------------------------------------------------------------
 137
 138 // the event tables connect the wxWidgets events with the functions (event
 139 // handlers) which process them. It can be also done at run-time, but for the
 140 // simple menu events like this the static method is much simpler.
 141 BEGIN_EVENT_TABLE(MyFrame, wxFrame)
 142     EVT_MENU(Minimal_Quit,  MyFrame::OnQuit)
 143     EVT_MENU(Minimal_Back, MyFrame::OnBack)
 144     EVT_MENU(Minimal_Forward, MyFrame::OnForward)
 145 END_EVENT_TABLE()
 146
 147 // Create a new application object: this macro will allow wxWidgets to create
 148 // the application object during program execution (it's better than using a
 149 // static object for many reasons) and also declares the accessor function
 150 // wxGetApp() which will return the reference of the right type (i.e. MyApp and
 151 // not wxApp)
 152 IMPLEMENT_APP(MyApp)
 153
 154 // ============================================================================
 155 // implementation
 156 // ============================================================================
 157
 158 // ----------------------------------------------------------------------------
 159 // the application class
 160 // ----------------------------------------------------------------------------
 161
 162 // `Main program' equivalent: the program execution "starts" here
 163 bool MyApp::OnInit()
 164 {
 165     if ( !wxApp::OnInit() )
 166         return false;
 167
 168     // Create the main application window
 169     MyFrame *frame = new MyFrame(_("wxHtmlWindow testing application"),
 170         wxDefaultPosition, wxSize(640, 480));
 171
 172     // Show it and tell the application that it's our main window
 173     // @@@ what does it do exactly, in fact? is it necessary here?
 174     frame->Show(true);
 175     SetTopWindow(frame);
 176     wxFileSystem::AddHandler(new MyVFS);
 177
 178     // success: wxApp::OnRun() will be called which will enter the main message
 179     // loop and the application will run. If we returned false here, the
 180     // application would exit immediately.
 181     return true;
 182 }
 183
 184 // ----------------------------------------------------------------------------
 185 // main frame
 186 // ----------------------------------------------------------------------------
 187
 188 wxHtmlWindow *html;
 189
 190 // frame constructor
 191 MyFrame::MyFrame(const wxString& title, const wxPoint& pos, const wxSize& size)
 192     : wxFrame((wxFrame *)NULL, wxID_ANY, title, pos, size)
 193 {
 194     SetIcon(wxICON(sample));
 195
 196     // create a menu bar
 197     wxMenu *menuFile = new wxMenu;
 198     wxMenu *menuNav = new wxMenu;
 199
 200     menuFile->Append(Minimal_Quit, _("E&xit"));
 201     menuNav->Append(Minimal_Back, _("Go &BACK"));
 202     menuNav->Append(Minimal_Forward, _("Go &FORWARD"));
 203
 204     // now append the freshly created menu to the menu bar...
 205     wxMenuBar *menuBar = new wxMenuBar;
 206     menuBar->Append(menuFile, _("&File"));
 207     menuBar->Append(menuNav, _("&Navigate"));
 208
 209     // ... and attach this menu bar to the frame
 210     SetMenuBar(menuBar);
 211
 212 #if wxUSE_STATUSBAR
 213     CreateStatusBar(2);
 214 #endif // wxUSE_STATUSBAR
 215
 216     html = new wxHtmlWindow(this);
 217     html -> SetRelatedFrame(this, _("VFS Demo: '%s'"));
 218 #if wxUSE_STATUSBAR
 219     html -> SetRelatedStatusBar(1);
 220 #endif // wxUSE_STATUSBAR
 221     html -> LoadPage(wxT("start.htm"));
 222 }
 223
 224
 225 // event handlers
 226
 227 void MyFrame::OnQuit(wxCommandEvent& WXUNUSED(event))
 228 {
 229     // true is to force the frame to close
 230     Close(true);
 231 }
 232
 233 void MyFrame::OnBack(wxCommandEvent& WXUNUSED(event))
 234 {
 235     if (!html -> HistoryBack()) wxMessageBox(_("You reached prehistory era!"));
 236 }
 237
 238 void MyFrame::OnForward(wxCommandEvent& WXUNUSED(event))
 239 {
 240     if (!html -> HistoryForward()) wxMessageBox(_("No more items in history!"));
 241 }