samples/erase/erase.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        erase.cpp
   3 // Purpose:     Erase wxWidgets 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 #if defined(__GNUG__) && !defined(__APPLE__)
  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" wxWidgets 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 OnChar( wxKeyEvent &event );
  77     void OnEraseBackground( wxEraseEvent &event );
  78
  79     wxBitmap    m_bitmap;
  80     wxString    m_text;
  81
  82 private:
  83     DECLARE_EVENT_TABLE()
  84 };
  85
  86 // ----------------------------------------------------------------------------
  87 // constants
  88 // ----------------------------------------------------------------------------
  89
  90 enum
  91 {
  92     // menu items
  93     ID_MENU_QUIT = 1,
  94 };
  95
  96
  97 // ----------------------------------------------------------------------------
  98 // the application class
  99 // ----------------------------------------------------------------------------
 100
 101 IMPLEMENT_APP(MyApp)
 102
 103 bool MyApp::OnInit()
 104 {
 105     MyFrame *frame = new MyFrame(_T("Erase sample"),
 106                                  wxPoint(50, 50), wxSize(450, 340));
 107
 108     frame->Show(true);
 109
 110     return true;
 111 }
 112
 113 // ----------------------------------------------------------------------------
 114 // main frame
 115 // ----------------------------------------------------------------------------
 116
 117 BEGIN_EVENT_TABLE(MyFrame, wxFrame)
 118     EVT_MENU(ID_MENU_QUIT,  MyFrame::OnQuit)
 119     EVT_MENU(wxID_ABOUT, MyFrame::OnAbout)
 120 END_EVENT_TABLE()
 121
 122 // frame constructor
 123 MyFrame::MyFrame(const wxString& title, const wxPoint& pos, const wxSize& size)
 124        : wxFrame((wxFrame *)NULL, wxID_ANY, title, pos, size)
 125 {
 126     SetIcon(wxICON(mondrian));
 127
 128     wxMenu *menuFile = new wxMenu(_T(""), wxMENU_TEAROFF);
 129
 130     wxMenu *helpMenu = new wxMenu;
 131     helpMenu->Append(wxID_ABOUT, _T("&About...\tCtrl-A"), _T("Show about dialog"));
 132
 133     menuFile->Append(ID_MENU_QUIT, _T("E&xit\tAlt-X"), _T("Quit this program"));
 134
 135     wxMenuBar *menuBar = new wxMenuBar();
 136     menuBar->Append(menuFile, _T("&File"));
 137     menuBar->Append(helpMenu, _T("&Help"));
 138
 139     SetMenuBar(menuBar);
 140
 141 #if wxUSE_STATUSBAR
 142     // create a status bar just for fun (by default with 1 pane only)
 143     CreateStatusBar(2);
 144     SetStatusText(_T("Welcome to wxWidgets erase sample!"));
 145 #endif // wxUSE_STATUSBAR
 146
 147     (void)new MyCanvas( this );
 148 }
 149
 150
 151 void MyFrame::OnQuit(wxCommandEvent& WXUNUSED(event))
 152 {
 153     Close(true);
 154 }
 155
 156 void MyFrame::OnAbout(wxCommandEvent& WXUNUSED(event))
 157 {
 158     wxMessageBox(_T("This sample shows how you can draw custom background."),
 159                  _T("About Erase Sample"), wxOK | wxICON_INFORMATION, this);
 160 }
 161
 162
 163 BEGIN_EVENT_TABLE(MyCanvas, wxScrolledWindow)
 164     EVT_PAINT(  MyCanvas::OnPaint)
 165     EVT_CHAR(  MyCanvas::OnChar)
 166     EVT_ERASE_BACKGROUND(  MyCanvas::OnEraseBackground)
 167 END_EVENT_TABLE()
 168
 169 MyCanvas::MyCanvas( MyFrame *parent )
 170         : wxScrolledWindow( parent, wxID_ANY, wxDefaultPosition, wxDefaultSize,
 171                             wxScrolledWindowStyle |
 172                             wxNO_FULL_REPAINT_ON_RESIZE|
 173                             wxSUNKEN_BORDER )
 174 {
 175     SetScrollbars( 10, 10, 40, 100, 0, 0 );
 176
 177     m_bitmap = wxBitmap( wxICON(mondrian) );
 178
 179     new wxStaticBitmap( this, wxID_ANY, m_bitmap, wxPoint(80,20) );
 180 }
 181
 182 void MyCanvas::OnChar( wxKeyEvent &event )
 183 {
 184 #if wxUSE_UNICODE
 185     if (event.m_uniChar)
 186     {
 187         m_text += event.m_uniChar;
 188         Refresh();
 189         return;
 190     }
 191 #endif
 192
 193     // some test cases
 194     switch (event.m_keyCode)
 195     {
 196         case WXK_UP: m_text += wxT( "<UP>" ); break;
 197         case WXK_LEFT: m_text += wxT( "<LEFT>" ); break;
 198         case WXK_RIGHT: m_text += wxT( "<RIGHT>" ); break;
 199         case WXK_DOWN: m_text += wxT( "<DOWN>" ); break;
 200         case WXK_RETURN: m_text += wxT( "<ENTER>" ); break;
 201         default: m_text += event.m_keyCode; break;
 202     }
 203
 204 }
 205
 206 void MyCanvas::OnPaint( wxPaintEvent &WXUNUSED(event) )
 207 {
 208     wxPaintDC dc(this);
 209     PrepareDC( dc );
 210
 211     dc.SetBrush( *wxBLACK_BRUSH );
 212     dc.DrawRectangle( 0,0,200,50 );
 213
 214     dc.DrawBitmap( m_bitmap, 10, 20, true );
 215
 216     dc.SetTextForeground(*wxBLUE);
 217     dc.DrawText(_T("This text is drawn from OnPaint"), 65, 65);
 218
 219     wxString tmp;
 220     tmp.Printf( _T("Hit any key to display more text: %s"), m_text.c_str() );
 221     int w,h;
 222     dc.GetTextExtent( tmp, &w, &h );
 223     dc.SetBrush( *wxWHITE_BRUSH );
 224     dc.DrawRectangle( 65, 85, w, h );
 225     dc.DrawText( tmp, 65, 85 );
 226
 227 #if 0
 228     wxRegionIterator upd( GetUpdateRegion() );
 229     while (upd)
 230     {
 231         wxLogDebug( _T("Paint: %d %d %d %d"), upd.GetX(), upd.GetY(), upd.GetWidth(), upd.GetHeight() );
 232         upd ++;
 233     }
 234 #endif
 235
 236 #if 0
 237     wxSize size = GetSize();
 238     wxSize client_size = GetClientSize();
 239     wxLogDebug( _T("size %d %d client_size %d %d"), size.x, size.y, client_size.x, client_size.y );
 240 #endif
 241
 242 #if 0
 243     int i;
 244     dc.SetPen( *wxWHITE_PEN );
 245     for (i = 0; i < 20; i += 2)
 246        dc.DrawLine( i,i, i+100,i );
 247
 248     dc.SetPen( *wxWHITE_PEN );
 249     for (i = 200; i < 220; i += 2)
 250        dc.DrawLine( i-200,i, i-100,i );
 251
 252     wxRegion region( 110, 110, 80, 80 );
 253     wxRegion hole( 130, 130, 40, 1 );
 254     region.Intersect( hole );
 255     dc.SetClippingRegion( region );
 256
 257     dc.SetBrush( *wxRED_BRUSH );
 258     dc.DrawRectangle( 100, 100, 200, 200 );
 259
 260     dc.DestroyClippingRegion();
 261
 262     dc.SetPen( *wxTRANSPARENT_PEN );
 263
 264     wxRegion strip( 110, 200, 30, 1 );
 265     wxRegionIterator it( strip );
 266     while (it)
 267     {
 268         dc.DrawRectangle( it.GetX(), it.GetY(), it.GetWidth(), it.GetHeight() );
 269         it ++;
 270     }
 271 #endif // 0
 272 }
 273
 274 void MyCanvas::OnEraseBackground( wxEraseEvent& event )
 275 {
 276     wxDC& dc = *event.GetDC();
 277     dc.SetPen(*wxGREEN_PEN);
 278
 279     // this line is needed, otherwise the junk is left on win the background
 280     dc.Clear();
 281
 282     wxSize size = GetClientSize();
 283     for ( int x = 0; x < size.x; x+= 10 )
 284     {
 285         dc.DrawLine(x, 0, x, size.y);
 286     }
 287
 288     for ( int y = 0; y < size.y; y+= 10 )
 289     {
 290         dc.DrawLine(0, y, size.x, y);
 291     }
 292
 293     dc.SetTextForeground(*wxRED);
 294     dc.DrawText(_T("This text is drawn from OnEraseBackground"), 60, 60);
 295 }
 296