samples/scroll/scroll.cpp

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        scroll.cpp
   3 // Purpose:     wxScrolledWindow sample
   4 // Author:      Robert Roebling
   5 // Modified by:
   6 // Created:
   7 // RCS-ID:      $Id$
   8 // Copyright:   (C) 1998 Robert Roebling, 2002 Ron Lee, 2003 Matt Gregory
   9 // Licence:     wxWindows license
  10 /////////////////////////////////////////////////////////////////////////////
  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 #ifndef WX_PRECOMP
  20 #include "wx/wx.h"
  21 #endif
  22
  23 #include "wx/image.h"
  24 #include "wx/listctrl.h"
  25 #include "wx/sizer.h"
  26 #include "wx/log.h"
  27
  28 const long ID_QUIT       = wxID_EXIT;
  29 const long ID_ABOUT      = wxID_ABOUT;
  30 const long ID_DELETE_ALL = 100;
  31 const long ID_INSERT_NEW = 101;
  32
  33 // ----------------------------------------------------------------------
  34 // a trivial example
  35 // ----------------------------------------------------------------------
  36
  37 // MySimpleCanvas: a scrolled window which draws a simple rectangle
  38 class MySimpleCanvas: public wxScrolledWindow
  39 {
  40 public:
  41     MySimpleCanvas() { }
  42     MySimpleCanvas(wxWindow *parent);
  43
  44 private:
  45     void OnPaint(wxPaintEvent& event);
  46
  47     enum
  48     {
  49         CANVAS_WIDTH = 292,
  50         CANVAS_HEIGHT = 297
  51     };
  52
  53     DECLARE_DYNAMIC_CLASS(MyCanvas)
  54     DECLARE_EVENT_TABLE()
  55 };
  56
  57 IMPLEMENT_DYNAMIC_CLASS(MySimpleCanvas, wxScrolledWindow)
  58
  59 BEGIN_EVENT_TABLE(MySimpleCanvas, wxScrolledWindow)
  60   EVT_PAINT(      MySimpleCanvas::OnPaint)
  61 END_EVENT_TABLE()
  62
  63 MySimpleCanvas::MySimpleCanvas(wxWindow *parent)
  64               : wxScrolledWindow(parent, wxID_ANY,
  65                                  wxDefaultPosition,
  66                                  wxDefaultSize,
  67                                  wxSUNKEN_BORDER)
  68 {
  69     SetScrollRate( 10, 10 );
  70     SetVirtualSize( CANVAS_WIDTH, CANVAS_HEIGHT );
  71     SetBackgroundColour( *wxWHITE );
  72 }
  73
  74 void MySimpleCanvas::OnPaint( wxPaintEvent &WXUNUSED(event) )
  75 {
  76     wxPaintDC dc(this);
  77     PrepareDC( dc );
  78
  79     dc.SetPen( *wxRED_PEN );
  80     dc.SetBrush( *wxTRANSPARENT_BRUSH );
  81     dc.DrawRectangle( 0, 0, CANVAS_WIDTH, CANVAS_HEIGHT );
  82 }
  83
  84 // MySimpleFrame: a frame which contains a MySimpleCanvas
  85 class MySimpleFrame: public wxFrame
  86 {
  87 public:
  88     MySimpleFrame();
  89
  90 private:
  91     void OnClose(wxCommandEvent& WXUNUSED(event)) { Close(true); }
  92
  93     DECLARE_DYNAMIC_CLASS(MySimpleFrame)
  94     DECLARE_EVENT_TABLE()
  95 };
  96
  97
  98 IMPLEMENT_DYNAMIC_CLASS( MySimpleFrame, wxFrame )
  99
 100 BEGIN_EVENT_TABLE(MySimpleFrame,wxFrame)
 101   EVT_MENU(wxID_CLOSE, MySimpleFrame::OnClose)
 102 END_EVENT_TABLE()
 103
 104 MySimpleFrame::MySimpleFrame()
 105              : wxFrame(NULL, wxID_ANY, _T("wxScrolledWindow sample"),
 106                        wxDefaultPosition, wxSize(200, 200))
 107 {
 108     wxMenu *file_menu = new wxMenu();
 109     file_menu->Append(wxID_CLOSE);
 110
 111     wxMenuBar *menu_bar = new wxMenuBar();
 112     menu_bar->Append(file_menu, _T("&File"));
 113
 114     SetMenuBar( menu_bar );
 115
 116     new MySimpleCanvas(this);
 117 }
 118
 119 // ----------------------------------------------------------------------
 120 // a complex example
 121 // ----------------------------------------------------------------------
 122
 123 // derived classes
 124
 125 class MyFrame;
 126 class MyApp;
 127
 128 // MyCanvas
 129
 130 class MyCanvas: public wxScrolledWindow
 131 {
 132 public:
 133     MyCanvas() {}
 134     MyCanvas( wxWindow *parent, wxWindowID, const wxPoint &pos, const wxSize &size );
 135     ~MyCanvas(){};
 136     void OnPaint( wxPaintEvent &event );
 137     void OnQueryPosition( wxCommandEvent &event );
 138     void OnAddButton( wxCommandEvent &event );
 139     void OnDeleteButton( wxCommandEvent &event );
 140     void OnMoveButton( wxCommandEvent &event );
 141     void OnScrollWin( wxCommandEvent &event );
 142     void OnMouseRightDown( wxMouseEvent &event );
 143     void OnMouseWheel( wxMouseEvent &event );
 144
 145     wxButton *m_button;
 146
 147     DECLARE_DYNAMIC_CLASS(MyCanvas)
 148     DECLARE_EVENT_TABLE()
 149 };
 150
 151
 152 // ----------------------------------------------------------------------------
 153 // Autoscrolling example.
 154 // ----------------------------------------------------------------------------
 155
 156 // this class uses the 'virtual' size attribute along with an internal
 157 // sizer to automatically set up scrollbars as needed
 158
 159 class MyAutoScrollWindow : public wxScrolledWindow
 160 {
 161 private:
 162
 163     wxButton    *m_button;
 164
 165 public:
 166
 167     MyAutoScrollWindow( wxWindow *parent );
 168
 169     void OnResizeClick( wxCommandEvent &WXUNUSED( event ) );
 170
 171     DECLARE_EVENT_TABLE()
 172 };
 173
 174
 175 // ----------------------------------------------------------------------------
 176 // MyScrolledWindow classes: examples of wxScrolledWindow usage
 177 // ----------------------------------------------------------------------------
 178
 179 // base class for both of them
 180 class MyScrolledWindowBase : public wxScrolledWindow
 181 {
 182 public:
 183     MyScrolledWindowBase(wxWindow *parent)
 184         : wxScrolledWindow(parent)
 185         , m_nLines( 100 )
 186     {
 187         wxClientDC dc(this);
 188         dc.GetTextExtent(_T("Line 17"), NULL, &m_hLine);
 189     }
 190
 191 protected:
 192     // the height of one line on screen
 193     wxCoord m_hLine;
 194
 195     // the number of lines we draw
 196     size_t m_nLines;
 197 };
 198
 199 // this class does "stupid" redrawing - it redraws everything each time
 200 // and sets the scrollbar extent directly.
 201
 202 class MyScrolledWindowDumb : public MyScrolledWindowBase
 203 {
 204 public:
 205     MyScrolledWindowDumb(wxWindow *parent) : MyScrolledWindowBase(parent)
 206     {
 207         // no horz scrolling
 208         SetScrollbars(0, m_hLine, 0, m_nLines + 1, 0, 0, true /* no refresh */);
 209     }
 210
 211     virtual void OnDraw(wxDC& dc);
 212 };
 213
 214 // this class does "smart" redrawing - only redraws the lines which must be
 215 // redrawn and sets the scroll rate and virtual size to affect the
 216 // scrollbars.
 217 //
 218 // Note that this class should produce identical results to the one above.
 219
 220 class MyScrolledWindowSmart : public MyScrolledWindowBase
 221 {
 222 public:
 223     MyScrolledWindowSmart(wxWindow *parent) : MyScrolledWindowBase(parent)
 224     {
 225         // no horz scrolling
 226         SetScrollRate( 0, m_hLine );
 227         SetVirtualSize( wxDefaultCoord, ( m_nLines + 1 ) * m_hLine );
 228     }
 229
 230     virtual void OnDraw(wxDC& dc);
 231 };
 232
 233 // ----------------------------------------------------------------------------
 234 // MyAutoTimedScrollingWindow: implements a text viewer with simple blocksize
 235 //                             selection to test auto-scrolling functionality
 236 // ----------------------------------------------------------------------------
 237
 238 class MyAutoTimedScrollingWindow : public wxScrolledWindow
 239 {
 240 protected:  // member data
 241     // test data variables
 242     static const wxChar* sm_testData;
 243     static const int sm_lineCnt; // line count
 244     static const int sm_lineLen; // line length in characters
 245     // sizes for graphical data
 246     wxCoord m_fontH, m_fontW;
 247     // selection tracking
 248     wxPoint m_selStart; // beginning of blockwise selection
 249     wxPoint m_cursor;   // end of blockwise selection (mouse position)
 250
 251 protected:  // gui stuff
 252     wxFont m_font;
 253
 254 public: // interface
 255     MyAutoTimedScrollingWindow( wxWindow* parent );
 256     wxRect DeviceCoordsToGraphicalChars(wxRect updRect) const;
 257     wxPoint DeviceCoordsToGraphicalChars(wxPoint pos) const;
 258     wxPoint GraphicalCharToDeviceCoords(wxPoint pos) const;
 259     wxRect LogicalCoordsToGraphicalChars(wxRect updRect) const;
 260     wxPoint LogicalCoordsToGraphicalChars(wxPoint pos) const;
 261     wxPoint GraphicalCharToLogicalCoords(wxPoint pos) const;
 262     void MyRefresh();
 263     bool IsSelected(int chX, int chY) const;
 264     static bool IsInside(int k, int bound1, int bound2);
 265     static wxRect DCNormalize(wxCoord x, wxCoord y, wxCoord w, wxCoord h);
 266
 267 protected: // event stuff
 268     void OnDraw(wxDC& dc);
 269     void OnMouseLeftDown(wxMouseEvent& event);
 270     void OnMouseLeftUp(wxMouseEvent& event);
 271     void OnMouseMove(wxMouseEvent& event);
 272     void OnMouseCaptureLost(wxMouseCaptureLostEvent& event);
 273     void OnScroll(wxScrollWinEvent& event);
 274
 275     DECLARE_EVENT_TABLE()
 276 };
 277
 278 // ----------------------------------------------------------------------------
 279 // MyFrame
 280 // ----------------------------------------------------------------------------
 281
 282 class MyFrame: public wxFrame
 283 {
 284 public:
 285     MyFrame();
 286
 287     void OnAbout( wxCommandEvent &event );
 288     void OnQuit( wxCommandEvent &event );
 289     void OnDeleteAll( wxCommandEvent &event );
 290     void OnInsertNew( wxCommandEvent &event );
 291
 292     MyCanvas         *m_canvas;
 293     wxTextCtrl       *m_log;
 294
 295     DECLARE_DYNAMIC_CLASS(MyFrame)
 296     DECLARE_EVENT_TABLE()
 297 };
 298
 299 // ----------------------------------------------------------------------------
 300 // MyApp
 301 // ----------------------------------------------------------------------------
 302
 303 class MyApp: public wxApp
 304 {
 305 public:
 306     virtual bool OnInit();
 307 };
 308
 309
 310 // ----------------------------------------------------------------------------
 311 // main program
 312 // ----------------------------------------------------------------------------
 313
 314 IMPLEMENT_APP(MyApp)
 315
 316 // ids
 317
 318 const long   ID_ADDBUTTON   = wxNewId();
 319 const long   ID_DELBUTTON   = wxNewId();
 320 const long   ID_MOVEBUTTON  = wxNewId();
 321 const long   ID_SCROLLWIN   = wxNewId();
 322 const long   ID_QUERYPOS    = wxNewId();
 323
 324 const long   ID_NEWBUTTON   = wxNewId();
 325
 326 // ----------------------------------------------------------------------------
 327 // MyCanvas
 328 // ----------------------------------------------------------------------------
 329
 330 IMPLEMENT_DYNAMIC_CLASS(MyCanvas, wxScrolledWindow)
 331
 332 BEGIN_EVENT_TABLE(MyCanvas, wxScrolledWindow)
 333   EVT_PAINT(                  MyCanvas::OnPaint)
 334   EVT_RIGHT_DOWN(             MyCanvas::OnMouseRightDown)
 335   EVT_MOUSEWHEEL(             MyCanvas::OnMouseWheel)
 336   EVT_BUTTON( ID_QUERYPOS,    MyCanvas::OnQueryPosition)
 337   EVT_BUTTON( ID_ADDBUTTON,   MyCanvas::OnAddButton)
 338   EVT_BUTTON( ID_DELBUTTON,   MyCanvas::OnDeleteButton)
 339   EVT_BUTTON( ID_MOVEBUTTON,  MyCanvas::OnMoveButton)
 340   EVT_BUTTON( ID_SCROLLWIN,   MyCanvas::OnScrollWin)
 341 END_EVENT_TABLE()
 342
 343 MyCanvas::MyCanvas( wxWindow *parent, wxWindowID id,
 344                     const wxPoint &pos, const wxSize &size )
 345     : wxScrolledWindow( parent, id, pos, size, wxSUNKEN_BORDER | wxTAB_TRAVERSAL, _T("test canvas") )
 346 {
 347     SetScrollRate( 10, 10 );
 348     SetVirtualSize( 500, 1000 );
 349
 350     (void) new wxButton( this, ID_ADDBUTTON,  _T("add button"), wxPoint(10,10) );
 351     (void) new wxButton( this, ID_DELBUTTON,  _T("del button"), wxPoint(10,40) );
 352     (void) new wxButton( this, ID_MOVEBUTTON, _T("move button"), wxPoint(150,10) );
 353     (void) new wxButton( this, ID_SCROLLWIN,  _T("scroll win"), wxPoint(250,10) );
 354
 355 #if 0
 356
 357     wxString choices[] =
 358     {
 359         "This",
 360         "is one of my",
 361         "really",
 362         "wonderful",
 363         "examples."
 364     };
 365
 366     m_button = new wxButton( this, ID_QUERYPOS, "Query position", wxPoint(10,110) );
 367
 368     (void) new wxTextCtrl( this, wxID_ANY, "wxTextCtrl", wxPoint(10,150), wxSize(80,wxDefaultCoord) );
 369
 370     (void) new wxRadioButton( this, wxID_ANY, "Disable", wxPoint(10,190) );
 371
 372     (void) new wxComboBox( this, wxID_ANY, "This", wxPoint(10,230), wxDefaultSize, 5, choices );
 373
 374     (void) new wxRadioBox( this, wxID_ANY, "This", wxPoint(10,310), wxDefaultSize, 5, choices, 2, wxRA_SPECIFY_COLS );
 375
 376     (void) new wxRadioBox( this, wxID_ANY, "This", wxPoint(10,440), wxDefaultSize, 5, choices, 2, wxRA_SPECIFY_ROWS );
 377
 378     wxListCtrl *m_listCtrl = new wxListCtrl(
 379             this, wxID_ANY, wxPoint(200, 110), wxSize(180, 120),
 380             wxLC_REPORT | wxSIMPLE_BORDER | wxLC_SINGLE_SEL );
 381
 382     m_listCtrl->InsertColumn(0, "First", wxLIST_FORMAT_LEFT, 90);
 383     m_listCtrl->InsertColumn(1, "Last", wxLIST_FORMAT_LEFT, 90);
 384
 385     for ( int i=0; i < 30; i++)
 386     {
 387         char buf[20];
 388         sprintf(buf, "Item %d", i);
 389         m_listCtrl->InsertItem(i, buf);
 390     }
 391     m_listCtrl->SetItemState( 3, wxLIST_STATE_SELECTED, wxLIST_STATE_SELECTED );
 392
 393     (void) new wxListBox( this, wxID_ANY, wxPoint(260,280), wxSize(120,120), 5, choices, wxLB_ALWAYS_SB );
 394
 395 #endif
 396
 397     wxPanel *test = new wxPanel( this, wxID_ANY, wxPoint(10, 110), wxSize(130,50), wxSIMPLE_BORDER | wxTAB_TRAVERSAL );
 398     test->SetBackgroundColour( wxT("WHEAT") );
 399
 400 #if 0
 401
 402     wxButton *test2 = new wxButton( test, wxID_ANY, "Hallo", wxPoint(10,10) );
 403
 404     test = new wxPanel( this, wxID_ANY, wxPoint(160, 530), wxSize(130,120), wxSUNKEN_BORDER | wxTAB_TRAVERSAL );
 405     test->SetBackgroundColour( wxT("WHEAT") );
 406     test->SetCursor( wxCursor( wxCURSOR_NO_ENTRY ) );
 407     test2 = new wxButton( test, wxID_ANY, "Hallo", wxPoint(10,10) );
 408     test2->SetCursor( wxCursor( wxCURSOR_PENCIL ) );
 409
 410     test = new wxPanel( this, wxID_ANY, wxPoint(310, 530), wxSize(130,120), wxRAISED_BORDER | wxTAB_TRAVERSAL );
 411     test->SetBackgroundColour( wxT("WHEAT") );
 412     test->SetCursor( wxCursor( wxCURSOR_PENCIL ) );
 413     test2 = new wxButton( test, wxID_ANY, "Hallo", wxPoint(10,10) );
 414     test2->SetCursor( wxCursor( wxCURSOR_NO_ENTRY ) );
 415
 416 #endif
 417
 418     SetBackgroundColour( wxT("BLUE") );
 419
 420     SetCursor( wxCursor( wxCURSOR_IBEAM ) );
 421 }
 422
 423 void MyCanvas::OnMouseRightDown( wxMouseEvent &event )
 424 {
 425     wxPoint pt( event.GetPosition() );
 426     int x,y;
 427     CalcUnscrolledPosition( pt.x, pt.y, &x, &y );
 428     wxLogMessage( wxT("Mouse down event at: %d %d, scrolled: %d %d"), pt.x, pt.y, x, y );
 429 }
 430
 431 void MyCanvas::OnMouseWheel( wxMouseEvent &event )
 432 {
 433     wxPoint pt( event.GetPosition() );
 434     int x,y;
 435     CalcUnscrolledPosition( pt.x, pt.y, &x, &y );
 436     wxLogMessage( wxT("Mouse wheel event at: %d %d, scrolled: %d %d\n")
 437                   wxT("Rotation: %d, delta = %d"),
 438                   pt.x, pt.y, x, y,
 439                   event.GetWheelRotation(), event.GetWheelDelta() );
 440
 441     event.Skip();
 442 }
 443
 444 void MyCanvas::OnPaint( wxPaintEvent &WXUNUSED(event) )
 445 {
 446     wxPaintDC dc( this );
 447     PrepareDC( dc );
 448
 449     dc.DrawText( _T("Press mouse button to test calculations!"), 160, 50 );
 450
 451     dc.DrawText( _T("Some text"), 140, 140 );
 452
 453     dc.DrawRectangle( 100, 160, 200, 200 );
 454 }
 455
 456 void MyCanvas::OnQueryPosition( wxCommandEvent &WXUNUSED(event) )
 457 {
 458     wxPoint pt( m_button->GetPosition() );
 459     wxLogMessage( wxT("Position of \"Query position\" is %d %d"), pt.x, pt.y );
 460     pt = ClientToScreen( pt );
 461     wxLogMessage( wxT("Position of \"Query position\" on screen is %d %d"), pt.x, pt.y );
 462 }
 463
 464 void MyCanvas::OnAddButton( wxCommandEvent &WXUNUSED(event) )
 465 {
 466     wxLogMessage( wxT("Inserting button at position 10,70...") );
 467     wxButton *button = new wxButton( this, ID_NEWBUTTON, wxT("new button"), wxPoint(10,70), wxSize(80,25) );
 468     wxPoint pt( button->GetPosition() );
 469     wxLogMessage( wxT("-> Position after inserting %d %d"), pt.x, pt.y );
 470 }
 471
 472 void MyCanvas::OnDeleteButton( wxCommandEvent &WXUNUSED(event) )
 473 {
 474     wxLogMessage( wxT("Deleting button inserted with \"Add button\"...") );
 475     wxWindow *win = FindWindow( ID_NEWBUTTON );
 476     if (win)
 477        win->Destroy();
 478     else
 479        wxLogMessage( wxT("-> No window with id = ID_NEWBUTTON found.") );
 480 }
 481
 482 void MyCanvas::OnMoveButton( wxCommandEvent &event )
 483 {
 484     wxLogMessage( wxT("Moving button 10 pixels downward..") );
 485     wxWindow *win = FindWindow( event.GetId() );
 486     wxPoint pt( win->GetPosition() );
 487     wxLogMessage( wxT("-> Position before move is %d %d"), pt.x, pt.y );
 488     win->Move( wxDefaultCoord, pt.y + 10 );
 489     pt = win->GetPosition();
 490     wxLogMessage( wxT("-> Position after move is %d %d"), pt.x, pt.y );
 491 }
 492
 493 void MyCanvas::OnScrollWin( wxCommandEvent &WXUNUSED(event) )
 494 {
 495     wxLogMessage( wxT("Scrolling 2 units up.\nThe white square and the controls should move equally!") );
 496     int x,y;
 497     GetViewStart( &x, &y );
 498     Scroll( wxDefaultCoord, y+2 );
 499 }
 500
 501 // ----------------------------------------------------------------------------
 502 // MyAutoScrollWindow
 503 // ----------------------------------------------------------------------------
 504
 505 const long   ID_RESIZEBUTTON = wxNewId();
 506 const wxSize SMALL_BUTTON( 100, 50 );
 507 const wxSize LARGE_BUTTON( 300, 100 );
 508
 509 BEGIN_EVENT_TABLE( MyAutoScrollWindow, wxScrolledWindow)
 510   EVT_BUTTON( ID_RESIZEBUTTON,    MyAutoScrollWindow::OnResizeClick)
 511 END_EVENT_TABLE()
 512
 513 MyAutoScrollWindow::MyAutoScrollWindow( wxWindow *parent )
 514     : wxScrolledWindow( parent, -1, wxDefaultPosition, wxDefaultSize,
 515                         wxSUNKEN_BORDER|wxScrolledWindowStyle )
 516 {
 517     SetBackgroundColour( wxT("GREEN") );
 518
 519     // Set the rate we'd like for scrolling.
 520
 521     SetScrollRate( 5, 5 );
 522
 523     // Populate a sizer with a 'resizing' button and some
 524     // other static decoration
 525
 526     wxFlexGridSizer  *innersizer = new wxFlexGridSizer( 2, 2 );
 527
 528     m_button = new wxButton( this,
 529                              ID_RESIZEBUTTON,
 530                              _T("Press me"),
 531                              wxDefaultPosition,
 532                              SMALL_BUTTON );
 533
 534     m_button->SetSizeHints( SMALL_BUTTON.GetWidth(), SMALL_BUTTON.GetHeight() );
 535
 536     innersizer->Add( m_button,
 537                      0,
 538                      wxALIGN_CENTER | wxALL,
 539                      20 );
 540
 541     innersizer->Add( new wxStaticText( this, wxID_ANY, _T("This is just") ),
 542                     0,
 543                     wxALIGN_CENTER );
 544
 545     innersizer->Add( new wxStaticText( this, wxID_ANY, _T("some decoration") ),
 546                     0,
 547                     wxALIGN_CENTER );
 548
 549     innersizer->Add( new wxStaticText( this, wxID_ANY, _T("for you to scroll...") ),
 550                     0,
 551                     wxALIGN_CENTER );
 552
 553     // Then use the sizer to set the scrolled region size.
 554
 555     SetSizer( innersizer );
 556 }
 557
 558 void MyAutoScrollWindow::OnResizeClick( wxCommandEvent &WXUNUSED( event ) )
 559 {
 560     // Arbitrarily resize the button to change the minimum size of
 561     // the (scrolled) sizer.
 562
 563     if( m_button->GetSize() == SMALL_BUTTON )
 564         m_button->SetSizeHints( LARGE_BUTTON.GetWidth(), LARGE_BUTTON.GetHeight() );
 565     else
 566         m_button->SetSizeHints( SMALL_BUTTON.GetWidth(), SMALL_BUTTON.GetHeight() );
 567
 568     // Force update layout and scrollbars, since nothing we do here
 569     // necessarily generates a size event which would do it for us.
 570
 571     FitInside();
 572 }
 573
 574 // ----------------------------------------------------------------------------
 575 // MyFrame
 576 // ----------------------------------------------------------------------------
 577
 578 IMPLEMENT_DYNAMIC_CLASS( MyFrame, wxFrame )
 579
 580 BEGIN_EVENT_TABLE(MyFrame,wxFrame)
 581   EVT_MENU    (ID_DELETE_ALL, MyFrame::OnDeleteAll)
 582   EVT_MENU    (ID_INSERT_NEW,  MyFrame::OnInsertNew)
 583   EVT_MENU    (ID_ABOUT, MyFrame::OnAbout)
 584   EVT_MENU    (ID_QUIT,  MyFrame::OnQuit)
 585 END_EVENT_TABLE()
 586
 587 MyFrame::MyFrame()
 588        : wxFrame( (wxFrame *)NULL, wxID_ANY, _T("wxScrolledWindow sample"),
 589                   wxPoint(20,20), wxSize(800,500) )
 590 {
 591     wxMenu *file_menu = new wxMenu();
 592     file_menu->Append( ID_DELETE_ALL, _T("Delete all"));
 593     file_menu->Append( ID_INSERT_NEW, _T("Insert new"));
 594     file_menu->Append( ID_ABOUT,      _T("&About.."));
 595     file_menu->Append( ID_QUIT,       _T("E&xit\tAlt-X"));
 596
 597     wxMenuBar *menu_bar = new wxMenuBar();
 598     menu_bar->Append(file_menu, _T("&File"));
 599
 600     SetMenuBar( menu_bar );
 601
 602 #if wxUSE_STATUSBAR
 603     CreateStatusBar(2);
 604     int widths[] = { -1, 100 };
 605     SetStatusWidths( 2, widths );
 606 #endif // wxUSE_STATUSBAR
 607
 608      wxBoxSizer *topsizer = new wxBoxSizer( wxHORIZONTAL );
 609      // subsizer splits topsizer down the middle
 610      wxBoxSizer *subsizer = new wxBoxSizer( wxVERTICAL );
 611
 612     // Setting an explicit size here is superfluous, it will be overridden
 613     // by the sizer in any case.
 614     m_canvas = new MyCanvas( this, wxID_ANY, wxPoint(0,0), wxSize(100,100) );
 615
 616     // This is done with ScrollRate/VirtualSize in MyCanvas ctor now,
 617     // both should produce identical results.
 618     //m_canvas->SetScrollbars( 10, 10, 50, 100 );
 619
 620     subsizer->Add( m_canvas, 1, wxEXPAND );
 621     subsizer->Add( new MyAutoScrollWindow( this ), 1, wxEXPAND );
 622
 623     wxSizer *sizerBtm = new wxBoxSizer(wxHORIZONTAL);
 624     sizerBtm->Add( new MyScrolledWindowDumb(this), 1, wxEXPAND );
 625     sizerBtm->Add( new MyScrolledWindowSmart(this), 1, wxEXPAND );
 626     subsizer->Add( sizerBtm, 1, wxEXPAND );
 627
 628     topsizer->Add( subsizer, 1, wxEXPAND );
 629     topsizer->Add( new MyAutoTimedScrollingWindow( this ), 1, wxEXPAND );
 630
 631     SetSizer( topsizer );
 632 }
 633
 634 void MyFrame::OnDeleteAll( wxCommandEvent &WXUNUSED(event) )
 635 {
 636     m_canvas->DestroyChildren();
 637 }
 638
 639 void MyFrame::OnInsertNew( wxCommandEvent &WXUNUSED(event) )
 640 {
 641     (void)new wxButton( m_canvas, wxID_ANY, _T("Hello"), wxPoint(100,100) );
 642 }
 643
 644 void MyFrame::OnQuit( wxCommandEvent &WXUNUSED(event) )
 645 {
 646   Close( true );
 647 }
 648
 649 void MyFrame::OnAbout( wxCommandEvent &WXUNUSED(event) )
 650 {
 651    (void)wxMessageBox( _T("wxScroll demo\n")
 652                        _T("Robert Roebling (c) 1998\n")
 653                        _T("Autoscrolling examples\n")
 654                        _T("Ron Lee (c) 2002\n")
 655                        _T("Auto-timed-scrolling example\n")
 656                        _T("Matt Gregory (c) 2003\n"),
 657                        _T("About wxScroll Demo"),
 658                        wxICON_INFORMATION | wxOK );
 659 }
 660
 661 //-----------------------------------------------------------------------------
 662 // MyApp
 663 //-----------------------------------------------------------------------------
 664
 665 bool MyApp::OnInit()
 666 {
 667     if ( !wxApp::OnInit() )
 668         return false;
 669
 670     wxFrame *frame = new MyFrame();
 671     frame->Show( true );
 672
 673     frame = new MySimpleFrame();
 674     frame->Show();
 675
 676     return true;
 677 }
 678
 679 // ----------------------------------------------------------------------------
 680 // MyScrolledWindowXXX
 681 // ----------------------------------------------------------------------------
 682
 683 void MyScrolledWindowDumb::OnDraw(wxDC& dc)
 684 {
 685     // this is useful to see which lines are redrawn
 686     static size_t s_redrawCount = 0;
 687     dc.SetTextForeground(s_redrawCount++ % 2 ? *wxRED : *wxBLUE);
 688
 689     wxCoord y = 0;
 690     for ( size_t line = 0; line < m_nLines; line++ )
 691     {
 692         wxCoord yPhys;
 693         CalcScrolledPosition(0, y, NULL, &yPhys);
 694
 695         dc.DrawText(wxString::Format(_T("Line %u (logical %d, physical %d)"),
 696                                      unsigned(line), y, yPhys), 0, y);
 697         y += m_hLine;
 698     }
 699 }
 700
 701 void MyScrolledWindowSmart::OnDraw(wxDC& dc)
 702 {
 703     // this is useful to see which lines are redrawn
 704     static size_t s_redrawCount = 0;
 705     dc.SetTextForeground(s_redrawCount++ % 2 ? *wxRED : *wxBLUE);
 706
 707     // update region is always in device coords, translate to logical ones
 708     wxRect rectUpdate = GetUpdateRegion().GetBox();
 709     CalcUnscrolledPosition(rectUpdate.x, rectUpdate.y,
 710                            &rectUpdate.x, &rectUpdate.y);
 711
 712     size_t lineFrom = rectUpdate.y / m_hLine,
 713            lineTo = rectUpdate.GetBottom() / m_hLine;
 714
 715     if ( lineTo > m_nLines - 1)
 716         lineTo = m_nLines - 1;
 717
 718     wxCoord y = lineFrom*m_hLine;
 719     for ( size_t line = lineFrom; line <= lineTo; line++ )
 720     {
 721         wxCoord yPhys;
 722         CalcScrolledPosition(0, y, NULL, &yPhys);
 723
 724         dc.DrawText(wxString::Format(_T("Line %u (logical %d, physical %d)"),
 725                                      unsigned(line), y, yPhys), 0, y);
 726         y += m_hLine;
 727     }
 728 }
 729
 730 // ----------------------------------------------------------------------------
 731 // MyAutoTimedScrollingWindow
 732 // ----------------------------------------------------------------------------
 733
 734 BEGIN_EVENT_TABLE(MyAutoTimedScrollingWindow, wxScrolledWindow)
 735     EVT_LEFT_DOWN(MyAutoTimedScrollingWindow::OnMouseLeftDown)
 736     EVT_LEFT_UP(MyAutoTimedScrollingWindow::OnMouseLeftUp)
 737     EVT_MOTION(MyAutoTimedScrollingWindow::OnMouseMove)
 738     EVT_MOUSE_CAPTURE_LOST(MyAutoTimedScrollingWindow::OnMouseCaptureLost)
 739     EVT_SCROLLWIN(MyAutoTimedScrollingWindow::OnScroll)
 740 END_EVENT_TABLE()
 741
 742 MyAutoTimedScrollingWindow::MyAutoTimedScrollingWindow(wxWindow* parent)
 743     : wxScrolledWindow(parent, wxID_ANY, wxDefaultPosition, wxDefaultSize
 744             //, wxSUNKEN_BORDER) // can't seem to do it this way
 745             , wxVSCROLL | wxHSCROLL | wxSUNKEN_BORDER)
 746     , m_selStart(-1, -1), m_cursor(-1, -1)
 747     , m_font(9, wxFONTFAMILY_TELETYPE, wxFONTSTYLE_NORMAL
 748             , wxFONTWEIGHT_NORMAL)
 749 {
 750     wxClientDC dc(this);
 751     // query dc for text size
 752     dc.SetFont(m_font);
 753     dc.GetTextExtent(wxString(_T("A")), &m_fontW, &m_fontH);
 754     // set up the virtual window
 755     SetScrollbars(m_fontW, m_fontH, sm_lineLen, sm_lineCnt);
 756 }
 757
 758 wxRect MyAutoTimedScrollingWindow::DeviceCoordsToGraphicalChars
 759         (wxRect updRect) const
 760 {
 761     wxPoint pos(updRect.GetPosition());
 762     pos = DeviceCoordsToGraphicalChars(pos);
 763     updRect.x = pos.x;
 764     updRect.y = pos.y;
 765     updRect.width /= m_fontW;
 766     updRect.height /= m_fontH;
 767     // the *CoordsToGraphicalChars() funcs round down to upper-left corner,
 768     //   so an off-by-one correction is needed
 769     ++updRect.width; // kludge
 770     ++updRect.height; // kludge
 771     return updRect;
 772 }
 773
 774 wxPoint MyAutoTimedScrollingWindow::DeviceCoordsToGraphicalChars
 775         (wxPoint pos) const
 776 {
 777     pos.x /= m_fontW;
 778     pos.y /= m_fontH;
 779     int vX, vY;
 780     GetViewStart(&vX, &vY);
 781     pos.x += vX;
 782     pos.y += vY;
 783     return pos;
 784 }
 785
 786 wxPoint MyAutoTimedScrollingWindow::GraphicalCharToDeviceCoords
 787         (wxPoint pos) const
 788 {
 789     int vX, vY;
 790     GetViewStart(&vX, &vY);
 791     pos.x -= vX;
 792     pos.y -= vY;
 793     pos.x *= m_fontW;
 794     pos.y *= m_fontH;
 795     return pos;
 796 }
 797
 798 wxRect MyAutoTimedScrollingWindow::LogicalCoordsToGraphicalChars
 799         (wxRect updRect) const
 800 {
 801     wxPoint pos(updRect.GetPosition());
 802     pos = LogicalCoordsToGraphicalChars(pos);
 803     updRect.x = pos.x;
 804     updRect.y = pos.y;
 805     updRect.width /= m_fontW;
 806     updRect.height /= m_fontH;
 807     // the *CoordsToGraphicalChars() funcs round down to upper-left corner,
 808     //   so an off-by-one correction is needed
 809     ++updRect.width; // kludge
 810     ++updRect.height; // kludge
 811     return updRect;
 812 }
 813
 814 wxPoint MyAutoTimedScrollingWindow::LogicalCoordsToGraphicalChars
 815         (wxPoint pos) const
 816 {
 817     pos.x /= m_fontW;
 818     pos.y /= m_fontH;
 819     return pos;
 820 }
 821
 822 wxPoint MyAutoTimedScrollingWindow::GraphicalCharToLogicalCoords
 823         (wxPoint pos) const
 824 {
 825     pos.x *= m_fontW;
 826     pos.y *= m_fontH;
 827     return pos;
 828 }
 829
 830 void MyAutoTimedScrollingWindow::MyRefresh()
 831 {
 832     static wxPoint lastSelStart(-1, -1), lastCursor(-1, -1);
 833     // refresh last selected area (to deselect previously selected text)
 834     wxRect lastUpdRect(
 835             GraphicalCharToDeviceCoords(lastSelStart),
 836             GraphicalCharToDeviceCoords(lastCursor)
 837         );
 838     // off-by-one corrections, necessary because it's not possible to know
 839     //   when to round up until rect is normalized by lastUpdRect constructor
 840     lastUpdRect.width += m_fontW; // kludge
 841     lastUpdRect.height += m_fontH; // kludge
 842     // refresh currently selected (to select previously unselected text)
 843     wxRect updRect(
 844             GraphicalCharToDeviceCoords(m_selStart),
 845             GraphicalCharToDeviceCoords(m_cursor)
 846         );
 847     // off-by-one corrections
 848     updRect.width += m_fontW; // kludge
 849     updRect.height += m_fontH; // kludge
 850     // find necessary refresh areas
 851     wxCoord rx = lastUpdRect.x;
 852     wxCoord ry = lastUpdRect.y;
 853     wxCoord rw = updRect.x - lastUpdRect.x;
 854     wxCoord rh = lastUpdRect.height;
 855     if (rw && rh) {
 856         RefreshRect(DCNormalize(rx, ry, rw, rh));
 857     }
 858     rx = updRect.x;
 859     ry = updRect.y + updRect.height;
 860     rw= updRect.width;
 861     rh = (lastUpdRect.y + lastUpdRect.height) - (updRect.y + updRect.height);
 862     if (rw && rh) {
 863         RefreshRect(DCNormalize(rx, ry, rw, rh));
 864     }
 865     rx = updRect.x + updRect.width;
 866     ry = lastUpdRect.y;
 867     rw = (lastUpdRect.x + lastUpdRect.width) - (updRect.x + updRect.width);
 868     rh = lastUpdRect.height;
 869     if (rw && rh) {
 870         RefreshRect(DCNormalize(rx, ry, rw, rh));
 871     }
 872     rx = updRect.x;
 873     ry = lastUpdRect.y;
 874     rw = updRect.width;
 875     rh = updRect.y - lastUpdRect.y;
 876     if (rw && rh) {
 877         RefreshRect(DCNormalize(rx, ry, rw, rh));
 878     }
 879     // update last
 880     lastSelStart = m_selStart;
 881     lastCursor = m_cursor;
 882 }
 883
 884 bool MyAutoTimedScrollingWindow::IsSelected(int chX, int chY) const
 885 {
 886     if (IsInside(chX, m_selStart.x, m_cursor.x)
 887             && IsInside(chY, m_selStart.y, m_cursor.y)) {
 888         return true;
 889     }
 890     return false;
 891 }
 892
 893 bool MyAutoTimedScrollingWindow::IsInside(int k, int bound1, int bound2)
 894 {
 895     if ((k >= bound1 && k <= bound2) || (k >= bound2 && k <= bound1)) {
 896         return true;
 897     }
 898     return false;
 899 }
 900
 901 wxRect MyAutoTimedScrollingWindow::DCNormalize(wxCoord x, wxCoord y
 902         , wxCoord w, wxCoord h)
 903 {
 904     // this is needed to get rid of the graphical remnants from the selection
 905     // I think it's because DrawRectangle() excludes a pixel in either direction
 906     const int kludge = 1;
 907     // make (x, y) the top-left corner
 908     if (w < 0) {
 909         w = -w + kludge;
 910         x -= w;
 911     } else {
 912         x -= kludge;
 913         w += kludge;
 914     }
 915     if (h < 0) {
 916         h = -h + kludge;
 917         y -= h;
 918     } else {
 919         y -= kludge;
 920         h += kludge;
 921     }
 922     return wxRect(x, y, w, h);
 923 }
 924
 925 void MyAutoTimedScrollingWindow::OnDraw(wxDC& dc)
 926 {
 927     dc.SetFont(m_font);
 928     wxBrush normBrush(wxSystemSettings::GetColour(wxSYS_COLOUR_WINDOW)
 929             , wxSOLID);
 930     wxBrush selBrush(wxSystemSettings::GetColour(wxSYS_COLOUR_HIGHLIGHT)
 931             , wxSOLID);
 932     dc.SetPen(*wxTRANSPARENT_PEN);
 933     const wxString str = sm_testData;
 934     size_t strLength = str.length();
 935     wxString::const_iterator str_i;
 936
 937     // draw the characters
 938     // 1. for each update region
 939     for (wxRegionIterator upd(GetUpdateRegion()); upd; ++upd) {
 940         wxRect updRect = upd.GetRect();
 941         wxRect updRectInGChars(DeviceCoordsToGraphicalChars(updRect));
 942         // 2. for each row of chars in the update region
 943         for (int chY = updRectInGChars.y
 944                 ; chY <= updRectInGChars.y + updRectInGChars.height; ++chY) {
 945             // 3. for each character in the row
 946             bool isFirstX = true;
 947             for (int chX = updRectInGChars.x
 948                     ; chX <= updRectInGChars.x + updRectInGChars.width
 949                     ; ++chX) {
 950                 // 4. set up dc
 951                 if (IsSelected(chX, chY)) {
 952                     dc.SetBrush(selBrush);
 953                     dc.SetTextForeground( wxSystemSettings::GetColour
 954                             (wxSYS_COLOUR_HIGHLIGHTTEXT));
 955                 } else {
 956                     dc.SetBrush(normBrush);
 957                     dc.SetTextForeground( wxSystemSettings::GetColour
 958                             (wxSYS_COLOUR_WINDOWTEXT));
 959                 }
 960                 // 5. find position info
 961                 wxPoint charPos = GraphicalCharToLogicalCoords(wxPoint
 962                         (chX, chY));
 963                 // 6. draw!
 964                 dc.DrawRectangle(charPos.x, charPos.y, m_fontW, m_fontH);
 965                 size_t charIndex = chY * sm_lineLen + chX;
 966                 if (chY < sm_lineCnt &&
 967                     chX < sm_lineLen &&
 968                     charIndex < strLength)
 969                 {
 970                     if (isFirstX)
 971                     {
 972                         str_i = str.begin() + charIndex;
 973                         isFirstX = false;
 974                     }
 975                     dc.DrawText(*str_i, charPos.x, charPos.y);
 976                     ++str_i;
 977                 }
 978             }
 979         }
 980     }
 981 }
 982
 983 void MyAutoTimedScrollingWindow::OnMouseLeftDown(wxMouseEvent& event)
 984 {
 985     // initial press of mouse button sets the beginning of the selection
 986     m_selStart = DeviceCoordsToGraphicalChars(event.GetPosition());
 987     // set the cursor to the same position
 988     m_cursor = m_selStart;
 989     // draw/erase selection
 990     MyRefresh();
 991 }
 992
 993 void MyAutoTimedScrollingWindow::OnMouseLeftUp(wxMouseEvent& WXUNUSED(event))
 994 {
 995     // this test is necessary
 996     if (HasCapture()) {
 997         // uncapture mouse
 998         ReleaseMouse();
 999     }
1000 }
1001
1002 void MyAutoTimedScrollingWindow::OnMouseMove(wxMouseEvent& event)
1003 {
1004     // if user is dragging
1005     if (event.Dragging() && event.LeftIsDown()) {
1006         // set the new cursor position
1007         m_cursor = DeviceCoordsToGraphicalChars(event.GetPosition());
1008         // draw/erase selection
1009         MyRefresh();
1010         // capture mouse to activate auto-scrolling
1011         if (!HasCapture()) {
1012             CaptureMouse();
1013         }
1014     }
1015 }
1016
1017 void MyAutoTimedScrollingWindow::OnMouseCaptureLost(wxMouseCaptureLostEvent& WXUNUSED(event))
1018 {
1019     // we only capture mouse for timed scrolling, so nothing is needed here
1020     // other than making sure to not call event.Skip()
1021 }
1022
1023 void MyAutoTimedScrollingWindow::OnScroll(wxScrollWinEvent& event)
1024 {
1025     // need to move the cursor when autoscrolling
1026     // FIXME: the cursor also moves when the scrollbar arrows are clicked
1027     if (HasCapture()) {
1028         if (event.GetOrientation() == wxHORIZONTAL) {
1029             if (event.GetEventType() == wxEVT_SCROLLWIN_LINEUP) {
1030                 --m_cursor.x;
1031             } else if (event.GetEventType() == wxEVT_SCROLLWIN_LINEDOWN) {
1032                 ++m_cursor.x;
1033             }
1034         } else if (event.GetOrientation() == wxVERTICAL) {
1035             if (event.GetEventType() == wxEVT_SCROLLWIN_LINEUP) {
1036                 --m_cursor.y;
1037             } else if (event.GetEventType() == wxEVT_SCROLLWIN_LINEDOWN) {
1038                 ++m_cursor.y;
1039             }
1040         }
1041     }
1042     MyRefresh();
1043     event.Skip();
1044 }
1045
1046 const int MyAutoTimedScrollingWindow::sm_lineCnt = 125;
1047 const int MyAutoTimedScrollingWindow::sm_lineLen = 79;
1048 const wxChar* MyAutoTimedScrollingWindow::sm_testData =
1049 _T("162 Cult of the genius out of vanity. Because we think well of ourselves, but ")
1050 _T("nonetheless never suppose ourselves capable of producing a painting like one of ")
1051 _T("Raphael's or a dramatic scene like one of Shakespeare's, we convince ourselves ")
1052 _T("that the capacity to do so is quite extraordinarily marvelous, a wholly ")
1053 _T("uncommon accident, or, if we are still religiously inclined, a mercy from on ")
1054 _T("high. Thus our vanity, our self-love, promotes the cult of the genius: for only ")
1055 _T("if we think of him as being very remote from us, as a miraculum, does he not ")
1056 _T("aggrieve us (even Goethe, who was without envy, called Shakespeare his star of ")
1057 _T("the most distant heights [\"William! Stern der schonsten Ferne\": from Goethe's, ")
1058 _T("\"Between Two Worlds\"]; in regard to which one might recall the lines: \"the ")
1059 _T("stars, these we do not desire\" [from Goethe's, \"Comfort in Tears\"]). But, aside ")
1060 _T("from these suggestions of our vanity, the activity of the genius seems in no ")
1061 _T("way fundamentally different from the activity of the inventor of machines, the ")
1062 _T("scholar of astronomy or history, the master of tactics. All these activities ")
1063 _T("are explicable if one pictures to oneself people whose thinking is active in ")
1064 _T("one direction, who employ everything as material, who always zealously observe ")
1065 _T("their own inner life and that of others, who perceive everywhere models and ")
1066 _T("incentives, who never tire of combining together the means available to them. ")
1067 _T("Genius too does nothing except learn first how to lay bricks then how to build, ")
1068 _T("except continually seek for material and continually form itself around it. ")
1069 _T("Every activity of man is amazingly complicated, not only that of the genius: ")
1070 _T("but none is a \"miracle.\" Whence, then, the belief that genius exists only in ")
1071 _T("the artist, orator and philosopher? that only they have \"intuition\"? (Whereby ")
1072 _T("they are supposed to possess a kind of miraculous eyeglass with which they can ")
1073 _T("see directly into \"the essence of the thing\"!) It is clear that people speak of ")
1074 _T("genius only where the effects of the great intellect are most pleasant to them ")
1075 _T("and where they have no desire to feel envious. To call someone \"divine\" means: ")
1076 _T("\"here there is no need for us to compete.\" Then, everything finished and ")
1077 _T("complete is regarded with admiration, everything still becoming is undervalued. ")
1078 _T("But no one can see in the work of the artist how it has become; that is its ")
1079 _T("advantage, for wherever one can see the act of becoming one grows somewhat ")
1080 _T("cool. The finished and perfect art of representation repulses all thinking as ")
1081 _T("to how it has become; it tyrannizes as present completeness and perfection. ")
1082 _T("That is why the masters of the art of representation count above all as gifted ")
1083 _T("with genius and why men of science do not. In reality, this evaluation of the ")
1084 _T("former and undervaluation of the latter is only a piece of childishness in the ")
1085 _T("realm of reason. ")
1086 _T("\n\n")
1087 _T("163 The serious workman. Do not talk about giftedness, inborn talents! One can ")
1088 _T("name great men of all kinds who were very little gifted. The acquired ")
1089 _T("greatness, became \"geniuses\" (as we put it), through qualities the lack of ")
1090 _T("which no one who knew what they were would boast of: they all possessed that ")
1091 _T("seriousness of the efficient workman which first learns to construct the parts ")
1092 _T("properly before it ventures to fashion a great whole; they allowed themselves ")
1093 _T("time for it, because they took more pleasure in making the little, secondary ")
1094 _T("things well than in the effect of a dazzling whole. the recipe for becoming a ")
1095 _T("good novelist, for example, is easy to give, but to carry it out presupposes ")
1096 _T("qualities one is accustomed to overlook when one says \"I do not have enough ")
1097 _T("talent.\" One has only to make a hundred or so sketches for novels, none longer ")
1098 _T("than two pages but of such distinctness that every word in them is necessary; ")
1099 _T("one should write down anecdotes each day until one has learned how to give them ")
1100 _T("the most pregnant and effective form; one should be tireless in collecting and ")
1101 _T("describing human types and characters; one should above all relate things to ")
1102 _T("others and listen to others relate, keeping one's eyes and ears open for the ")
1103 _T("effect produced on those present, one should travel like a landscape painter or ")
1104 _T("costume designer; one should excerpt for oneself out of the individual sciences ")
1105 _T("everything that will produce an artistic effect when it is well described, one ")
1106 _T("should, finally, reflect on the motives of human actions, disdain no signpost ")
1107 _T("to instruction about them and be a collector of these things by day and night. ")
1108 _T("One should continue in this many-sided exercise some ten years: what is then ")
1109 _T("created in the workshop, however, will be fit to go out into the world. What, ")
1110 _T("however, do most people do? They begin, not with the parts, but with the whole. ")
1111 _T("Perhaps they chance to strike a right note, excite attention and from then on ")
1112 _T("strike worse and worse notes, for good, natural reasons. Sometimes, when the ")
1113 _T("character and intellect needed to formulate such a life-plan are lacking, fate ")
1114 _T("and need take their place and lead the future master step by step through all ")
1115 _T("the stipulations of his trade. ")
1116 _T("\n\n")
1117 _T("164 Peril and profit in the cult of the genius. The belief in great, superior, ")
1118 _T("fruitful spirits is not necessarily, yet nonetheless is very frequently ")
1119 _T("associated with that religious or semi-religious superstition that these ")
1120 _T("spirits are of supra-human origin and possess certain miraculous abilities by ")
1121 _T("virtue of which they acquire their knowledge by quite other means than the rest ")
1122 _T("of mankind. One ascribes to them, it seems, a direct view of the nature of the ")
1123 _T("world, as it were a hole in the cloak of appearance, and believes that, by ")
1124 _T("virtue of this miraculous seer's vision, they are able to communicate something ")
1125 _T("conclusive and decisive about man and the world without the toil and ")
1126 _T("rigorousness required by science. As long as there continue to be those who ")
1127 _T("believe in the miraculous in the domain of knowledge one can perhaps concede ")
1128 _T("that these people themselves derive some benefit from their belief, inasmuch as ")
1129 _T("through their unconditional subjection to the great spirits they create for ")
1130 _T("their own spirit during its time of development the finest form of discipline ")
1131 _T("and schooling. On the other hand, it is at least questionable whether the ")
1132 _T("superstitious belief in genius, in its privileges and special abilities, is of ")
1133 _T("benefit to the genius himself if it takes root in him. It is in any event a ")
1134 _T("dangerous sign when a man is assailed by awe of himself, whether it be the ")
1135 _T("celebrated Caesar's awe of Caesar or the awe of one's own genius now under ")
1136 _T("consideration; when the sacrificial incense which is properly rendered only to ")
1137 _T("a god penetrates the brain of the genius, so that his head begins to swim and ")
1138 _T("he comes to regard himself as something supra-human. The consequences that ")
1139 _T("slowly result are: the feeling of irresponsibility, of exceptional rights, the ")
1140 _T("belief that he confers a favor by his mere presence, insane rage when anyone ")
1141 _T("attempts even to compare him with others, let alone to rate him beneath them, ")
1142 _T("or to draw attention to lapses in his work. Because he ceases to practice ")
1143 _T("criticism of himself, at last one pinion after the other falls out of his ")
1144 _T("plumage: that superstitious eats at the roots of his powers and perhaps even ")
1145 _T("turns him into a hypocrite after his powers have fled from him. For the great ")
1146 _T("spirits themselves it is therefore probably more beneficial if they acquire an ")
1147 _T("insight into the nature and origin of their powers, if they grasp, that is to ")
1148 _T("say, what purely human qualities have come together in them and what fortunate ")
1149 _T("circumstances attended them: in the first place undiminished energy, resolute ")
1150 _T("application to individual goals, great personal courage, then the good fortune ")
1151 _T("to receive an upbringing which offered in the early years the finest teachers, ")
1152 _T("models and methods. To be sure, when their goal is the production of the ")
1153 _T("greatest possible effect, unclarity with regard to oneself and that ")
1154 _T("semi-insanity superadded to it has always achieved much; for what has been ")
1155 _T("admired and envied at all times has been that power in them by virtue of which ")
1156 _T("they render men will-less and sweep them away into the delusion that the ")
1157 _T("leaders they are following are supra-natural. Indeed, it elevates and inspires ")
1158 _T("men to believe that someone is in possession of supra-natural powers: to this ")
1159 _T("extent Plato was right to say [Plato: Phaedrus, 244a] that madness has brought ")
1160 _T("the greatest of blessings upon mankind. In rare individual cases this portion ")
1161 _T("of madness may, indeed, actually have been the means by which such a nature, ")
1162 _T("excessive in all directions, was held firmly together: in the life of ")
1163 _T("individuals, too, illusions that are in themselves poisons often play the role ")
1164 _T("of healers; yet, in the end, in the case of every \"genius\" who believes in his ")
1165 _T("own divinity the poison shows itself to the same degree as his \"genius\" grows ")
1166 _T("old: one may recall, for example, the case of Napoleon, whose nature certainly ")
1167 _T("grew into the mighty unity that sets him apart from all men of modern times ")
1168 _T("precisely through his belief in himself and his star and through the contempt ")
1169 _T("for men that flowed from it; until in the end, however, this same belief went ")
1170 _T("over into an almost insane fatalism, robbed him of his acuteness and swiftness ")
1171 _T("of perception, and became the cause of his destruction.");