samples/png/pngdemo.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        pngdemo.cpp
   3 // Purpose:     Demos PNG reading
   4 // Author:      Julian Smart
   5 // Modified by:
   6 // Created:     04/01/98
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) Julian Smart and Markus Holzem
   9 // Licence:     wxWindows license
  10 /////////////////////////////////////////////////////////////////////////////
  11
  12 #ifdef __GNUG__
  13 #pragma implementation "pngdemo.h"
  14 #endif
  15
  16 // For compilers that support precompilation, includes "wx.h".
  17 #include "wx/wxprec.h"
  18
  19 #ifdef __BORLANDC__
  20 #pragma hdrstop
  21 #endif
  22
  23 #ifdef __WXMSW__
  24 #include <wx/pnghand.h>
  25 #endif
  26
  27 #include "pngdemo.h"
  28
  29 MyFrame   *frame = NULL;
  30 wxBitmap  *g_TestBitmap = NULL;
  31
  32 IMPLEMENT_APP(MyApp)
  33
  34 MyApp::MyApp()
  35 {
  36 }
  37
  38 bool MyApp::OnInit(void)
  39 {
  40 #ifdef __WXMSW__
  41   wxBitmap::AddHandler(new wxPNGFileHandler);
  42 #endif
  43
  44   // Create the main frame window
  45   frame = new MyFrame(NULL, "wxPNGBitmap Demo", wxPoint(0, 0), wxSize(300, 300));
  46
  47   // Give it a status line
  48   frame->CreateStatusBar(2);
  49
  50   // Make a menubar
  51   wxMenu *file_menu = new wxMenu;
  52   wxMenu *help_menu = new wxMenu;
  53
  54   file_menu->Append(PNGDEMO_LOAD_FILE, "&Load file",                "Load file");
  55   file_menu->Append(PNGDEMO_QUIT, "E&xit",                "Quit program");
  56   help_menu->Append(PNGDEMO_ABOUT, "&About",              "About PNG demo");
  57
  58   wxMenuBar *menu_bar = new wxMenuBar;
  59
  60   menu_bar->Append(file_menu, "&File");
  61   menu_bar->Append(help_menu, "&Help");
  62
  63   // Associate the menu bar with the frame
  64   frame->SetMenuBar(menu_bar);
  65
  66   MyCanvas *canvas = new MyCanvas(frame, wxPoint(0, 0), wxSize(100, 100));
  67
  68   // Give it scrollbars: the virtual canvas is 20 * 50 = 1000 pixels in each direction
  69 //  canvas->SetScrollbars(20, 20, 50, 50, 4, 4);
  70   frame->canvas = canvas;
  71
  72   frame->Show(TRUE);
  73
  74   frame->SetStatusText("Hello, wxWindows");
  75
  76   return TRUE;
  77 }
  78
  79 BEGIN_EVENT_TABLE(MyFrame, wxFrame)
  80     EVT_MENU(PNGDEMO_QUIT,      MyFrame::OnQuit)
  81     EVT_MENU(PNGDEMO_ABOUT,     MyFrame::OnAbout)
  82     EVT_MENU(PNGDEMO_LOAD_FILE, MyFrame::OnLoadFile)
  83 END_EVENT_TABLE()
  84
  85 // Define my frame constructor
  86 MyFrame::MyFrame(wxFrame *frame, const wxString& title, const wxPoint& pos, const wxSize& size):
  87   wxFrame(frame, -1, title, pos, size)
  88 {
  89   canvas = NULL;
  90 }
  91
  92 void MyFrame::OnQuit(wxCommandEvent& event)
  93 {
  94     Close(TRUE);
  95 }
  96
  97 void MyFrame::OnAbout(wxCommandEvent& event)
  98 {
  99     (void)wxMessageBox("PNG demo\nJulian Smart (c) 1998",
 100             "About PNG Demo", wxOK);
 101 }
 102
 103 void MyFrame::OnLoadFile(wxCommandEvent& event)
 104 {
 105         // Show file selector.
 106         char *f = wxFileSelector("Open Image", NULL, NULL,"png",
 107                   "PNG files (*.png)|*.png");
 108
 109         if (!f)
 110           return;
 111
 112     if ( g_TestBitmap )
 113         delete g_TestBitmap;
 114     g_TestBitmap = new wxBitmap(f, wxBITMAP_TYPE_PNG);
 115     if (!g_TestBitmap->Ok())
 116     {
 117         delete g_TestBitmap;
 118         g_TestBitmap = NULL;
 119     }
 120
 121     canvas->Refresh();
 122 }
 123
 124 BEGIN_EVENT_TABLE(MyCanvas, wxScrolledWindow)
 125     EVT_PAINT(MyCanvas::OnPaint)
 126 END_EVENT_TABLE()
 127
 128 // Define a constructor for my canvas
 129 MyCanvas::MyCanvas(wxWindow *parent, const wxPoint& pos, const wxSize& size):
 130  wxScrolledWindow(parent, -1, pos, size)
 131 {
 132 }
 133
 134 MyCanvas::~MyCanvas(void)
 135 {
 136 }
 137
 138 // Define the repainting behaviour
 139 void MyCanvas::OnPaint(wxPaintEvent& event)
 140 {
 141   wxPaintDC dc(this);
 142   dc.SetPen(wxRED_PEN);
 143
 144   int i;
 145   for ( i = 0; i < 500; i += 10)
 146   {
 147     dc.DrawLine(0, i, 800, i);
 148   }
 149   if ( g_TestBitmap && g_TestBitmap->Ok() )
 150   {
 151     wxMemoryDC memDC;
 152     if ( g_TestBitmap->GetColourMap() )
 153     {
 154         memDC.SetColourMap(g_TestBitmap->GetColourMap());
 155         dc.SetColourMap(g_TestBitmap->GetColourMap());
 156     }
 157     memDC.SelectObject(g_TestBitmap);
 158
 159     // Normal, non-transparent blitting
 160     dc.Blit(20, 20, g_TestBitmap->GetWidth(), g_TestBitmap->GetHeight(), & memDC, 0, 0, wxCOPY, FALSE);
 161
 162     memDC.SelectObject(wxNullBitmap);
 163   }
 164
 165   if ( g_TestBitmap && g_TestBitmap->Ok() )
 166   {
 167     wxMemoryDC memDC;
 168     memDC.SelectObject(g_TestBitmap);
 169
 170     // Transparent blitting if there's a mask in the bitmap
 171     dc.Blit(20 + g_TestBitmap->GetWidth() + 20, 20, g_TestBitmap->GetWidth(), g_TestBitmap->GetHeight(), & memDC,
 172       0, 0, wxCOPY, TRUE);
 173
 174     memDC.SelectObject(wxNullBitmap);
 175   }
 176 }
 177
 178 // Define the behaviour for the frame closing
 179 // - must delete all frames except for the main one.
 180 bool MyFrame::OnClose(void)
 181 {
 182   Show(FALSE);
 183
 184   return TRUE;
 185 }
 186