minimal.cpp 8.93 KB
// ============================================================================
// declarations
// ============================================================================

// ----------------------------------------------------------------------------
// headers
// ----------------------------------------------------------------------------

// For compilers that support precompilation, includes "wx/wx.h".
#include "wx/wxprec.h"

#ifdef __BORLANDC__
    #pragma hdrstop
#endif

// for all others, include the necessary headers (this file is usually all you
// need because it includes almost all "standard" wxWindows headers)
#ifndef WX_PRECOMP
    #include "wx/wx.h"
#endif

#include <list>
using namespace std;

// ----------------------------------------------------------------------------
// resources
// ----------------------------------------------------------------------------

// the application icon (under Windows and OS/2 it is in resources)
#if defined(__WXGTK__) || defined(__WXMOTIF__) || defined(__WXMAC__) || defined(__WXMGL__) || defined(__WXX11__)
    #include "mondrian.xpm"
#endif

// ----------------------------------------------------------------------------
// private classes
// ----------------------------------------------------------------------------

// Define a new application type, each program should derive a class from wxApp
class MyApp : public wxApp
{
public:
    // override base class virtuals
    // ----------------------------

    // this one is called on application startup and is a good place for the app
    // initialization (doing it here and not in the ctor allows to have an error
    // return: if OnInit() returns false, the application terminates)
    virtual bool OnInit();
};


// Plots a line from one point to the other
class DoodleLine
{
 public:
  wxInt32 x1;
  wxInt32 y1;
  wxInt32 x2;
  wxInt32 y2;
};

// Contains a list of lines: represents a mouse-down doodle
class DoodleSegment
{
 public:
  list<DoodleLine> lines;
  bool empty() {return lines.begin()==lines.end();};
  void clear(){lines.clear();};
  void Draw(wxDC *dc);
};

// Define a new canvas type
class MyCanvas : public wxScrolledWindow
{
 private:
 DoodleSegment currentSegment;
 list<DoodleSegment> segments; 
 int xpos;
 int ypos;
 protected:
 public:
   
  MyCanvas(wxFrame *parent, const wxPoint& pos = wxDefaultPosition, const wxSize& size = wxDefaultSize, 
	  long style = 0)
	  :wxScrolledWindow(parent, -1, pos, size, style)
  {
	  SetScrollbars(1, 1, 1024, 768);
	  SetBackgroundColour(wxColour(_T("YELLOW")));
  };
  ~MyCanvas(void){};
  void OnPaint(wxPaintEvent& event);
  void OnMouse(wxMouseEvent& event);
  DECLARE_EVENT_TABLE()
};


// Define a new frame type: this is going to be our main frame
class MyFrame : public wxFrame
{
public:
    // ctor(s)
    MyFrame(const wxString& title, const wxPoint& pos, const wxSize& size,
            long style = wxDEFAULT_FRAME_STYLE);

    // event handlers (these functions should _not_ be virtual)
    void OnQuit(wxCommandEvent& event);
    void OnAbout(wxCommandEvent& event);

private:
    // any class wishing to process wxWindows events must use this macro
    DECLARE_EVENT_TABLE()
};

// ----------------------------------------------------------------------------
// constants
// ----------------------------------------------------------------------------

// IDs for the controls and the menu commands
enum
{
    // menu items
    Minimal_Quit = 1,

    // it is important for the id corresponding to the "About" command to have
    // this standard value as otherwise it won't be handled properly under Mac
    // (where it is special and put into the "Apple" menu)
    Minimal_About = wxID_ABOUT
};

// ----------------------------------------------------------------------------
// event tables and other macros for wxWindows
// ----------------------------------------------------------------------------

// the event tables connect the wxWindows events with the functions (event
// handlers) which process them. It can be also done at run-time, but for the
// simple menu events like this the static method is much simpler.
BEGIN_EVENT_TABLE(MyFrame, wxFrame)
    EVT_MENU(Minimal_Quit,  MyFrame::OnQuit)
    EVT_MENU(Minimal_About, MyFrame::OnAbout)
END_EVENT_TABLE()

// Create a new application object: this macro will allow wxWindows to create
// the application object during program execution (it's better than using a
// static object for many reasons) and also implements the accessor function
// wxGetApp() which will return the reference of the right type (i.e. MyApp and
// not wxApp)
IMPLEMENT_APP(MyApp)

// ============================================================================
// implementation
// ============================================================================

// ----------------------------------------------------------------------------
// the application class
// ----------------------------------------------------------------------------

// 'Main program' equivalent: the program execution "starts" here
bool MyApp::OnInit()
{
    // create the main application window
    MyFrame *frame = new MyFrame(_T("Minimal wxWindows App"),
                                 wxPoint(50, 50), wxSize(450, 340));

    // and show it (the frames, unlike simple controls, are not shown when
    // created initially)
    frame->Show(TRUE);

    // success: wxApp::OnRun() will be called which will enter the main message
    // loop and the application will run. If we returned FALSE here, the
    // application would exit immediately.
    return TRUE;
}

// ----------------------------------------------------------------------------
// main frame
// ----------------------------------------------------------------------------

// frame constructor
MyFrame::MyFrame(const wxString& title, const wxPoint& pos, const wxSize& size, long style)
       : wxFrame(NULL, -1, title, pos, size, style)
{
    // set the frame icon
    SetIcon(wxICON(mondrian));

#if wxUSE_MENUS
    // create a menu bar
    wxMenu *menuFile = new wxMenu;

    // the "About" item should be in the help menu
    wxMenu *helpMenu = new wxMenu;
    helpMenu->Append(Minimal_About, _T("&About...\tF1"), _T("Show about dialog"));

    menuFile->Append(Minimal_Quit, _T("E&xit\tAlt-X"), _T("Quit this program"));

    // now append the freshly created menu to the menu bar...
    wxMenuBar *menuBar = new wxMenuBar();
    menuBar->Append(menuFile, _T("&File"));
    menuBar->Append(helpMenu, _T("&Help"));

    // ... and attach this menu bar to the frame
    SetMenuBar(menuBar);
#endif // wxUSE_MENUS

#if wxUSE_STATUSBAR
    // create a status bar just for fun (by default with 1 pane only)
    CreateStatusBar(2);
    SetStatusText(_T("Welcome to wxWindows!"));
#endif // wxUSE_STATUSBAR
	new MyCanvas(this);
}


// event handlers

void MyFrame::OnQuit(wxCommandEvent& WXUNUSED(event))
{
    // TRUE is to force the frame to close
    Close(TRUE);
}

void MyFrame::OnAbout(wxCommandEvent& WXUNUSED(event))
{
    wxString msg;
    msg.Printf( _T("This is the About dialog of the minimal sample.\n")
                _T("Welcome to %s"), wxVERSION_STRING);

    wxMessageBox(msg, _T("About Minimal"), wxOK | wxICON_INFORMATION, this);
}



BEGIN_EVENT_TABLE(MyCanvas, wxScrolledWindow)
    EVT_PAINT(MyCanvas::OnPaint)
	EVT_MOUSE_EVENTS(MyCanvas::OnMouse)
END_EVENT_TABLE()


void MyCanvas::OnPaint(wxPaintEvent& event)
{
  wxSize size=GetSize();
  wxPaintDC dc(this);
  PrepareDC(dc);
  wxPen redPen(_T("RED"), 1, wxSOLID);
  wxBrush yellowBrush(_T("YELLOW"),wxSOLID);
  dc.SetPen(redPen);

  list<DoodleSegment>::iterator i;  
  for(i=segments.begin();i!=segments.end();++i)
    i->Draw(&dc);
  
  dc.SetPen(wxNullPen);
  dc.SetBrush(wxNullBrush);  
}

void MyCanvas::OnMouse(wxMouseEvent& event)
{
  wxClientDC dc(this);
  PrepareDC(dc);

  wxPen redPen(_T("RED"), 1, wxSOLID);
  dc.SetPen(redPen);

  int x,y;
  event.GetPosition(&x,&y);
  wxPoint pt(event.GetLogicalPosition(dc));

  if (HasCapture() && event.LeftUp())
  {
	ReleaseMouse();
    if (!currentSegment.empty())
    {
      // We've got a valid segment on mouse left up, so store it.
	  segments.push_back(currentSegment);
	  currentSegment.clear();
    }
  }

  if (HasCapture() && event.Dragging())
  {
    DoodleLine newLine;
    newLine.x1 = (long)xpos; 
    newLine.y1 = (long)ypos;
    newLine.x2 = pt.x; 
    newLine.y2 = pt.y;
    currentSegment.lines.push_back(newLine);
    dc.DrawLine( (long)xpos, (long)ypos, pt.x, pt.y);
    xpos = pt.x;
    ypos = pt.y;
  }
  if(event.LeftDown())
  {
	  CaptureMouse();
      currentSegment.clear();
      xpos = pt.x;
	  ypos = pt.y;
  }
}


void DoodleSegment::Draw(wxDC *dc)
{

  list<DoodleLine>::iterator i;  
  for(i=lines.begin();i!=lines.end();++i)
    dc->DrawLine(i->x1, i->y1, i->x2, i->y2);
}