samples/html/virtual/virtual.cpp

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