samples/erase/erase.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        erase.cpp
   3 // Purpose:     Erase wxWindows sample
   4 // Author:      Robert Roebling
   5 // Modified by:
   6 // Created:     04/01/98
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) Robert Roebling
   9 // Licence:     wxWindows licence
  10 /////////////////////////////////////////////////////////////////////////////
  11
  12 // ============================================================================
  13 // declarations
  14 // ============================================================================
  15
  16 // ----------------------------------------------------------------------------
  17 // headers
  18 // ----------------------------------------------------------------------------
  19
  20 #ifdef __GNUG__
  21     #pragma implementation "erase.cpp"
  22     #pragma interface "erase.cpp"
  23 #endif
  24
  25 // For compilers that support precompilation, includes "wx/wx.h".
  26 #include "wx/wxprec.h"
  27
  28 #ifdef __BORLANDC__
  29     #pragma hdrstop
  30 #endif
  31
  32 // for all others, include the necessary headers (this file is usually all you
  33 // need because it includes almost all "standard" wxWindows headers)
  34 #ifndef WX_PRECOMP
  35     #include "wx/wx.h"
  36 #endif
  37
  38 // ----------------------------------------------------------------------------
  39 // resources
  40 // ----------------------------------------------------------------------------
  41 // the application icon
  42 #if defined(__WXGTK__) || defined(__WXMOTIF__) || defined(__WXMAC__) || defined(__WXMGL__) || defined(__WXX11__)
  43     #include "mondrian.xpm"
  44 #endif
  45
  46 // ----------------------------------------------------------------------------
  47 // private classes
  48 // ----------------------------------------------------------------------------
  49
  50 class MyApp : public wxApp
  51 {
  52 public:
  53     virtual bool OnInit();
  54 };
  55
  56
  57 class MyFrame : public wxFrame
  58 {
  59 public:
  60     MyFrame(const wxString& title, const wxPoint& pos, const wxSize& size);
  61
  62     void OnQuit(wxCommandEvent& event);
  63     void OnAbout(wxCommandEvent& event);
  64
  65 private:
  66     DECLARE_EVENT_TABLE()
  67 };
  68
  69
  70 class MyCanvas : public wxScrolledWindow
  71 {
  72 public:
  73     MyCanvas( MyFrame *parent );
  74
  75     void OnPaint( wxPaintEvent &event );
  76     void OnEraseBackground( wxEraseEvent &event );
  77
  78     wxBitmap    m_bitmap;
  79
  80 private:
  81     DECLARE_EVENT_TABLE()
  82 };
  83
  84 // ----------------------------------------------------------------------------
  85 // constants
  86 // ----------------------------------------------------------------------------
  87
  88 enum
  89 {
  90     // menu items
  91     Minimal_Quit = 1,
  92     Minimal_About
  93 };
  94
  95
  96 // ----------------------------------------------------------------------------
  97 // the application class
  98 // ----------------------------------------------------------------------------
  99
 100 IMPLEMENT_APP(MyApp)
 101
 102 bool MyApp::OnInit()
 103 {
 104     MyFrame *frame = new MyFrame(_T("Minimal wxWindows App"),
 105                                  wxPoint(50, 50), wxSize(450, 340));
 106
 107     frame->Show(TRUE);
 108
 109     return TRUE;
 110 }
 111
 112 // ----------------------------------------------------------------------------
 113 // main frame
 114 // ----------------------------------------------------------------------------
 115
 116 BEGIN_EVENT_TABLE(MyFrame, wxFrame)
 117     EVT_MENU(Minimal_Quit,  MyFrame::OnQuit)
 118     EVT_MENU(Minimal_About, MyFrame::OnAbout)
 119 END_EVENT_TABLE()
 120
 121 // frame constructor
 122 MyFrame::MyFrame(const wxString& title, const wxPoint& pos, const wxSize& size)
 123        : wxFrame((wxFrame *)NULL, -1, title, pos, size)
 124 {
 125 #ifdef __WXMAC__
 126     wxApp::s_macAboutMenuItemId = Minimal_About;
 127 #endif
 128
 129     SetIcon(wxICON(mondrian));
 130
 131     wxMenu *menuFile = new wxMenu("", wxMENU_TEAROFF);
 132
 133     wxMenu *helpMenu = new wxMenu;
 134     helpMenu->Append(Minimal_About, _T("&About...\tCtrl-A"), _T("Show about dialog"));
 135
 136     menuFile->Append(Minimal_Quit, _T("E&xit\tAlt-X"), _T("Quit this program"));
 137
 138     wxMenuBar *menuBar = new wxMenuBar();
 139     menuBar->Append(menuFile, _T("&File"));
 140     menuBar->Append(helpMenu, _T("&Help"));
 141
 142     SetMenuBar(menuBar);
 143
 144 #if wxUSE_STATUSBAR
 145     // create a status bar just for fun (by default with 1 pane only)
 146     CreateStatusBar(2);
 147     SetStatusText(_T("Welcome to wxWindows erase sample!"));
 148 #endif // wxUSE_STATUSBAR
 149
 150     (void)new MyCanvas( this );
 151 }
 152
 153
 154 void MyFrame::OnQuit(wxCommandEvent& WXUNUSED(event))
 155 {
 156     Close(TRUE);
 157 }
 158
 159 void MyFrame::OnAbout(wxCommandEvent& WXUNUSED(event))
 160 {
 161     wxMessageBox(_T("This sample shows how you can draw custom background."),
 162                  _T("About Erase Sample"), wxOK | wxICON_INFORMATION, this);
 163 }
 164
 165
 166 BEGIN_EVENT_TABLE(MyCanvas, wxScrolledWindow)
 167     EVT_PAINT(  MyCanvas::OnPaint)
 168     EVT_ERASE_BACKGROUND(  MyCanvas::OnEraseBackground)
 169 END_EVENT_TABLE()
 170
 171 MyCanvas::MyCanvas( MyFrame *parent )
 172         : wxScrolledWindow( parent, -1, wxDefaultPosition, wxDefaultSize,
 173                             wxScrolledWindowStyle |
 174                             wxNO_FULL_REPAINT_ON_RESIZE|
 175                             wxSUNKEN_BORDER )
 176 {
 177     SetScrollbars( 10, 10, 40, 100, 0, 0 );
 178
 179     m_bitmap = wxBitmap( wxICON(mondrian) );
 180
 181     new wxStaticBitmap( this, -1, m_bitmap, wxPoint(80,20) );
 182 }
 183
 184 void MyCanvas::OnPaint( wxPaintEvent &event )
 185 {
 186     wxPaintDC dc(this);
 187     PrepareDC( dc );
 188
 189     dc.SetBrush( *wxBLACK_BRUSH );
 190     dc.DrawRectangle( 0,0,200,50 );
 191
 192     dc.DrawBitmap( m_bitmap, 10, 20, TRUE );
 193
 194     dc.SetTextForeground(*wxBLUE);
 195     dc.DrawText(_T("This text is drawn from OnPaint"), 65, 65);
 196
 197 #if 0
 198     wxRegionIterator upd( GetUpdateRegion() );
 199     while (upd)
 200     {
 201         wxLogDebug( "Paint: %d %d %d %d", upd.GetX(), upd.GetY(), upd.GetWidth(), upd.GetHeight() );
 202         upd ++;
 203     }
 204 #endif
 205
 206 #if 0
 207     wxSize size = GetSize();
 208     wxSize client_size = GetClientSize();
 209     wxLogDebug( "size %d %d client_size %d %d", size.x, size.y, client_size.x, client_size.y );
 210 #endif
 211
 212 #if 0
 213     int i;
 214     dc.SetPen( *wxWHITE_PEN );
 215     for (i = 0; i < 20; i += 2)
 216        dc.DrawLine( i,i, i+100,i );
 217
 218     dc.SetPen( *wxWHITE_PEN );
 219     for (i = 200; i < 220; i += 2)
 220        dc.DrawLine( i-200,i, i-100,i );
 221
 222     wxRegion region( 110, 110, 80, 80 );
 223     wxRegion hole( 130, 130, 40, 1 );
 224     region.Intersect( hole );
 225     dc.SetClippingRegion( region );
 226
 227     dc.SetBrush( *wxRED_BRUSH );
 228     dc.DrawRectangle( 100, 100, 200, 200 );
 229
 230     dc.DestroyClippingRegion();
 231
 232     dc.SetPen( *wxTRANSPARENT_PEN );
 233
 234     wxRegion strip( 110, 200, 30, 1 );
 235     wxRegionIterator it( strip );
 236     while (it)
 237     {
 238         dc.DrawRectangle( it.GetX(), it.GetY(), it.GetWidth(), it.GetHeight() );
 239         it ++;
 240     }
 241 #endif // 0
 242 }
 243
 244 void MyCanvas::OnEraseBackground( wxEraseEvent& event )
 245 {
 246     wxDC& dc = *event.GetDC();
 247     dc.SetPen(*wxGREEN_PEN);
 248
 249     // this line is needed, otherwise the junk is left on win the background
 250     dc.Clear();
 251
 252     wxSize size = GetClientSize();
 253     for ( int x = 0; x < size.x; x+= 10 )
 254     {
 255         dc.DrawLine(x, 0, x, size.y);
 256     }
 257
 258     for ( int y = 0; y < size.y; y+= 10 )
 259     {
 260         dc.DrawLine(0, y, size.x, y);
 261     }
 262
 263     dc.SetTextForeground(*wxRED);
 264     dc.DrawText(_T("This text is drawn from OnEraseBackground"), 60, 60);
 265 }
 266