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