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