include/wx/scrolwin.h

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        wx/scrolwin.h
   3 // Purpose:     wxScrolledWindow, wxScrolledControl and wxScrollHelper
   4 // Author:      Vadim Zeitlin
   5 // Modified by:
   6 // Created:     30.08.00
   7 // Copyright:   (c) 2000 Vadim Zeitlin <zeitlin@dptmaths.ens-cachan.fr>
   8 // Licence:     wxWindows licence
   9 /////////////////////////////////////////////////////////////////////////////
  10
  11 #ifndef _WX_SCROLWIN_H_BASE_
  12 #define _WX_SCROLWIN_H_BASE_
  13
  14 #include "wx/panel.h"
  15
  16 class WXDLLIMPEXP_FWD_CORE wxScrollHelperEvtHandler;
  17 class WXDLLIMPEXP_FWD_BASE wxTimer;
  18
  19 // default scrolled window style: scroll in both directions
  20 #define wxScrolledWindowStyle (wxHSCROLL | wxVSCROLL)
  21
  22 // values for the second argument of wxScrollHelper::ShowScrollbars()
  23 enum wxScrollbarVisibility
  24 {
  25     wxSHOW_SB_NEVER = -1,   // never show the scrollbar at all
  26     wxSHOW_SB_DEFAULT,      // show scrollbar only if it is needed
  27     wxSHOW_SB_ALWAYS        // always show scrollbar, even if not needed
  28 };
  29
  30 // ----------------------------------------------------------------------------
  31 // The hierarchy of scrolling classes is a bit complicated because we want to
  32 // put as much functionality as possible in a mix-in class not deriving from
  33 // wxWindow so that other classes could derive from the same base class on all
  34 // platforms irrespectively of whether they are native controls (and hence
  35 // don't use our scrolling) or not.
  36 //
  37 // So we have
  38 //
  39 //                          wxAnyScrollHelperBase
  40 //                                   |
  41 //                                   |
  42 //                                  \|/
  43 //                           wxScrollHelperBase
  44 //                                   |
  45 //                                   |
  46 //                                  \|/
  47 //      wxWindow               wxScrollHelper
  48 //       |  \                   /        /
  49 //       |   \                 /        /
  50 //       |    _|             |_        /
  51 //       |     wxScrolledWindow       /
  52 //       |                           /
  53 //      \|/                         /
  54 //   wxControl                     /
  55 //         \                      /
  56 //          \                    /
  57 //           _|                |_
  58 //            wxScrolledControl
  59 //
  60 // ----------------------------------------------------------------------------
  61
  62 // This class allows reusing some of wxScrollHelperBase functionality in
  63 // wxVarScrollHelperBase in wx/vscroll.h without duplicating its code.
  64 class WXDLLIMPEXP_CORE wxAnyScrollHelperBase
  65 {
  66 public:
  67     wxEXPLICIT wxAnyScrollHelperBase(wxWindow* win);
  68     virtual ~wxAnyScrollHelperBase() {}
  69
  70     // Disable use of keyboard keys for scrolling. By default cursor movement
  71     // keys (including Home, End, Page Up and Down) are used to scroll the
  72     // window appropriately. If the derived class uses these keys for something
  73     // else, e.g. changing the currently selected item, this function can be
  74     // used to disable this behaviour as it's not only not necessary then but
  75     // can actually be actively harmful if another object forwards a keyboard
  76     // event corresponding to one of the above keys to us using
  77     // ProcessWindowEvent() because the event will always be processed which
  78     // can be undesirable.
  79     void DisableKeyboardScrolling() { m_kbdScrollingEnabled = false; }
  80
  81     // Override this function to draw the graphic (or just process EVT_PAINT)
  82     virtual void OnDraw(wxDC& WXUNUSED(dc)) { }
  83
  84     // change the DC origin according to the scroll position.
  85     virtual void DoPrepareDC(wxDC& dc) = 0;
  86
  87     // Simple accessor for the window that is really being scrolled.
  88     wxWindow *GetTargetWindow() const { return m_targetWindow; }
  89
  90
  91     // The methods called from the window event handlers.
  92     void HandleOnChar(wxKeyEvent& event);
  93     void HandleOnPaint(wxPaintEvent& event);
  94
  95 protected:
  96     // the window that receives the scroll events and the window to actually
  97     // scroll, respectively
  98     wxWindow *m_win,
  99              *m_targetWindow;
 100
 101     // whether cursor keys should scroll the window
 102     bool m_kbdScrollingEnabled;
 103 };
 104
 105 // This is the class containing the guts of (uniform) scrolling logic.
 106 class WXDLLIMPEXP_CORE wxScrollHelperBase : public wxAnyScrollHelperBase
 107 {
 108 public:
 109     // ctor must be given the associated window
 110     wxScrollHelperBase(wxWindow *winToScroll);
 111     virtual ~wxScrollHelperBase();
 112
 113     // configure the scrolling
 114     virtual void SetScrollbars(int pixelsPerUnitX, int pixelsPerUnitY,
 115                                int noUnitsX, int noUnitsY,
 116                                int xPos = 0, int yPos = 0,
 117                                bool noRefresh = false );
 118
 119     // scroll to the given (in logical coords) position
 120     //
 121     // notice that for backwards compatibility reasons Scroll() is virtual as
 122     // the existing code could override it but new code should override
 123     // DoScroll() instead
 124     virtual void Scroll(int x, int y) { DoScroll(x, y); }
 125     virtual void Scroll(const wxPoint& pt) { DoScroll(pt.x, pt.y); }
 126
 127     // get/set the page size for this orientation (wxVERTICAL/wxHORIZONTAL)
 128     int GetScrollPageSize(int orient) const;
 129     void SetScrollPageSize(int orient, int pageSize);
 130
 131     // get the number of lines the window can scroll,
 132     // returns 0 if no scrollbars are there.
 133     int GetScrollLines( int orient ) const;
 134
 135     // Set the x, y scrolling increments.
 136     void SetScrollRate( int xstep, int ystep );
 137
 138     // get the size of one logical unit in physical ones
 139     void GetScrollPixelsPerUnit(int *pixelsPerUnitX, int *pixelsPerUnitY) const;
 140
 141     // Set scrollbar visibility: it is possible to show scrollbar only if it is
 142     // needed (i.e. if our virtual size is greater than the current size of the
 143     // associated window), always (as wxALWAYS_SHOW_SB style does) or never (in
 144     // which case you should provide some other way to scroll the window as the
 145     // user wouldn't be able to do it at all)
 146     void ShowScrollbars(wxScrollbarVisibility horz, wxScrollbarVisibility vert)
 147     {
 148         DoShowScrollbars(horz, vert);
 149     }
 150
 151     // Test whether the specified scrollbar is shown.
 152     virtual bool IsScrollbarShown(int orient) const = 0;
 153
 154     // Enable/disable Windows scrolling in either direction. If true, wxWidgets
 155     // scrolls the canvas and only a bit of the canvas is invalidated; no
 156     // Clear() is necessary. If false, the whole canvas is invalidated and a
 157     // Clear() is necessary. Disable for when the scroll increment is used to
 158     // actually scroll a non-constant distance
 159     //
 160     // Notice that calling this method with a false argument doesn't disable
 161     // scrolling the window in this direction, it just changes the mechanism by
 162     // which it is implemented to not use wxWindow::ScrollWindow().
 163     virtual void EnableScrolling(bool x_scrolling, bool y_scrolling);
 164
 165     // Get the view start
 166     void GetViewStart(int *x, int *y) const { DoGetViewStart(x, y); }
 167
 168     wxPoint GetViewStart() const
 169     {
 170         wxPoint pt;
 171         DoGetViewStart(&pt.x, &pt.y);
 172         return pt;
 173     }
 174
 175     // Set the scale factor, used in PrepareDC
 176     void SetScale(double xs, double ys) { m_scaleX = xs; m_scaleY = ys; }
 177     double GetScaleX() const { return m_scaleX; }
 178     double GetScaleY() const { return m_scaleY; }
 179
 180     // translate between scrolled and unscrolled coordinates
 181     void CalcScrolledPosition(int x, int y, int *xx, int *yy) const
 182         {  DoCalcScrolledPosition(x, y, xx, yy); }
 183     wxPoint CalcScrolledPosition(const wxPoint& pt) const
 184     {
 185         wxPoint p2;
 186         DoCalcScrolledPosition(pt.x, pt.y, &p2.x, &p2.y);
 187         return p2;
 188     }
 189
 190     void CalcUnscrolledPosition(int x, int y, int *xx, int *yy) const
 191         {  DoCalcUnscrolledPosition(x, y, xx, yy); }
 192     wxPoint CalcUnscrolledPosition(const wxPoint& pt) const
 193     {
 194         wxPoint p2;
 195         DoCalcUnscrolledPosition(pt.x, pt.y, &p2.x, &p2.y);
 196         return p2;
 197     }
 198
 199     void DoCalcScrolledPosition(int x, int y, int *xx, int *yy) const;
 200     void DoCalcUnscrolledPosition(int x, int y, int *xx, int *yy) const;
 201
 202     // Adjust the scrollbars
 203     virtual void AdjustScrollbars() = 0;
 204
 205     // Calculate scroll increment
 206     int CalcScrollInc(wxScrollWinEvent& event);
 207
 208     // Normally the wxScrolledWindow will scroll itself, but in some rare
 209     // occasions you might want it to scroll [part of] another window (e.g. a
 210     // child of it in order to scroll only a portion the area between the
 211     // scrollbars (spreadsheet: only cell area will move).
 212     void SetTargetWindow(wxWindow *target);
 213
 214     void SetTargetRect(const wxRect& rect) { m_rectToScroll = rect; }
 215     wxRect GetTargetRect() const { return m_rectToScroll; }
 216
 217     virtual void DoPrepareDC(wxDC& dc);
 218
 219     // are we generating the autoscroll events?
 220     bool IsAutoScrolling() const { return m_timerAutoScroll != NULL; }
 221
 222     // stop generating the scroll events when mouse is held outside the window
 223     void StopAutoScrolling();
 224
 225     // this method can be overridden in a derived class to forbid sending the
 226     // auto scroll events - note that unlike StopAutoScrolling() it doesn't
 227     // stop the timer, so it will be called repeatedly and will typically
 228     // return different values depending on the current mouse position
 229     //
 230     // the base class version just returns true
 231     virtual bool SendAutoScrollEvents(wxScrollWinEvent& event) const;
 232
 233     // the methods to be called from the window event handlers
 234     void HandleOnScroll(wxScrollWinEvent& event);
 235     void HandleOnSize(wxSizeEvent& event);
 236     void HandleOnMouseEnter(wxMouseEvent& event);
 237     void HandleOnMouseLeave(wxMouseEvent& event);
 238 #if wxUSE_MOUSEWHEEL
 239     void HandleOnMouseWheel(wxMouseEvent& event);
 240 #endif // wxUSE_MOUSEWHEEL
 241     void HandleOnChildFocus(wxChildFocusEvent& event);
 242
 243 #if WXWIN_COMPATIBILITY_2_8
 244     wxDEPRECATED(
 245         void OnScroll(wxScrollWinEvent& event) { HandleOnScroll(event); }
 246     )
 247 #endif // WXWIN_COMPATIBILITY_2_8
 248
 249 protected:
 250     // get pointer to our scroll rect if we use it or NULL
 251     const wxRect *GetScrollRect() const
 252     {
 253         return m_rectToScroll.width != 0 ? &m_rectToScroll : NULL;
 254     }
 255
 256     // get the size of the target window
 257     wxSize GetTargetSize() const
 258     {
 259         return m_rectToScroll.width != 0 ? m_rectToScroll.GetSize()
 260                                          : m_targetWindow->GetClientSize();
 261     }
 262
 263     void GetTargetSize(int *w, int *h) const
 264     {
 265         wxSize size = GetTargetSize();
 266         if ( w )
 267             *w = size.x;
 268         if ( h )
 269             *h = size.y;
 270     }
 271
 272     // implementation of public methods with the same name
 273     virtual void DoGetViewStart(int *x, int *y) const;
 274     virtual void DoScroll(int x, int y) = 0;
 275     virtual void DoShowScrollbars(wxScrollbarVisibility horz,
 276                                   wxScrollbarVisibility vert) = 0;
 277
 278     // implementations of various wxWindow virtual methods which should be
 279     // forwarded to us (this can be done by WX_FORWARD_TO_SCROLL_HELPER())
 280     bool ScrollLayout();
 281     void ScrollDoSetVirtualSize(int x, int y);
 282     wxSize ScrollGetBestVirtualSize() const;
 283
 284     // change just the target window (unlike SetWindow which changes m_win as
 285     // well)
 286     void DoSetTargetWindow(wxWindow *target);
 287
 288     // delete the event handler we installed
 289     void DeleteEvtHandler();
 290
 291     // this function should be overridden to return the size available for
 292     // m_targetWindow inside m_win of the given size
 293     //
 294     // the default implementation is only good for m_targetWindow == m_win
 295     // case, if we're scrolling a subwindow you must override this method
 296     virtual wxSize GetSizeAvailableForScrollTarget(const wxSize& size)
 297     {
 298         // returning just size from here is wrong but it was decided that it is
 299         // not wrong enough to break the existing code (which doesn't override
 300         // this recently added function at all) by adding this assert
 301         //
 302         // wxASSERT_MSG( m_targetWindow == m_win, "must be overridden" );
 303
 304         return size;
 305     }
 306
 307
 308     double                m_scaleX;
 309     double                m_scaleY;
 310
 311     wxRect                m_rectToScroll;
 312
 313     wxTimer              *m_timerAutoScroll;
 314
 315     // The number of pixels to scroll in horizontal and vertical directions
 316     // respectively.
 317     //
 318     // If 0, means that the scrolling in the given direction is disabled.
 319     int                   m_xScrollPixelsPerLine;
 320     int                   m_yScrollPixelsPerLine;
 321     int                   m_xScrollPosition;
 322     int                   m_yScrollPosition;
 323     int                   m_xScrollLines;
 324     int                   m_yScrollLines;
 325     int                   m_xScrollLinesPerPage;
 326     int                   m_yScrollLinesPerPage;
 327
 328     bool                  m_xScrollingEnabled;
 329     bool                  m_yScrollingEnabled;
 330
 331 #if wxUSE_MOUSEWHEEL
 332     int m_wheelRotation;
 333 #endif // wxUSE_MOUSEWHEEL
 334
 335     wxScrollHelperEvtHandler *m_handler;
 336
 337     wxDECLARE_NO_COPY_CLASS(wxScrollHelperBase);
 338 };
 339
 340 // this macro can be used in a wxScrollHelper-derived class to forward wxWindow
 341 // methods to corresponding wxScrollHelper methods
 342 #define WX_FORWARD_TO_SCROLL_HELPER()                                         \
 343 public:                                                                       \
 344     virtual void PrepareDC(wxDC& dc) { DoPrepareDC(dc); }                     \
 345     virtual bool Layout() { return ScrollLayout(); }                          \
 346     virtual bool CanScroll(int orient) const                                  \
 347         { return IsScrollbarShown(orient); }                                  \
 348     virtual void DoSetVirtualSize(int x, int y)                               \
 349         { ScrollDoSetVirtualSize(x, y); }                                     \
 350     virtual wxSize GetBestVirtualSize() const                                 \
 351         { return ScrollGetBestVirtualSize(); }
 352
 353 // include the declaration of the real wxScrollHelper
 354 #if defined(__WXGTK20__) && !defined(__WXUNIVERSAL__)
 355     #include "wx/gtk/scrolwin.h"
 356 #elif defined(__WXGTK__) && !defined(__WXUNIVERSAL__)
 357     #include "wx/gtk1/scrolwin.h"
 358 #else
 359     #define wxHAS_GENERIC_SCROLLWIN
 360     #include "wx/generic/scrolwin.h"
 361 #endif
 362
 363 // ----------------------------------------------------------------------------
 364 // wxScrolled<T>: a wxWindow which knows how to scroll
 365 // ----------------------------------------------------------------------------
 366
 367 // helper class for wxScrolled<T> below
 368 struct WXDLLIMPEXP_CORE wxScrolledT_Helper
 369 {
 370     static wxSize FilterBestSize(const wxWindow *win,
 371                                  const wxScrollHelper *helper,
 372                                  const wxSize& origBest);
 373 #ifdef __WXMSW__
 374     static WXLRESULT FilterMSWWindowProc(WXUINT nMsg, WXLRESULT origResult);
 375 #endif
 376 };
 377
 378 // Scrollable window base on window type T. This used to be wxScrolledWindow,
 379 // but wxScrolledWindow includes wxControlContainer functionality and that's
 380 // not always desirable.
 381 template<class T>
 382 class wxScrolled : public T,
 383                    public wxScrollHelper,
 384                    private wxScrolledT_Helper
 385 {
 386 public:
 387     wxScrolled() : wxScrollHelper(this) { }
 388     wxScrolled(wxWindow *parent,
 389                wxWindowID winid = wxID_ANY,
 390                const wxPoint& pos = wxDefaultPosition,
 391                const wxSize& size = wxDefaultSize,
 392                long style = wxScrolledWindowStyle,
 393                const wxString& name = wxPanelNameStr)
 394         : wxScrollHelper(this)
 395     {
 396         Create(parent, winid, pos, size, style, name);
 397     }
 398
 399     bool Create(wxWindow *parent,
 400                 wxWindowID winid,
 401                 const wxPoint& pos = wxDefaultPosition,
 402                 const wxSize& size = wxDefaultSize,
 403                 long style = wxScrolledWindowStyle,
 404                 const wxString& name = wxPanelNameStr)
 405     {
 406         m_targetWindow = this;
 407
 408 #ifdef __WXMAC__
 409         this->MacSetClipChildren(true);
 410 #endif
 411
 412         // by default, we're scrollable in both directions (but if one of the
 413         // styles is specified explicitly, we shouldn't add the other one
 414         // automatically)
 415         if ( !(style & (wxHSCROLL | wxVSCROLL)) )
 416             style |= wxHSCROLL | wxVSCROLL;
 417
 418 #ifdef __WXOSX__
 419         bool retval = T::Create(parent, winid, pos, size, style, name);
 420         if ( retval && (style & wxALWAYS_SHOW_SB) )
 421             ShowScrollbars(wxSHOW_SB_ALWAYS, wxSHOW_SB_ALWAYS);
 422         return retval;
 423 #else
 424         if ( style & wxALWAYS_SHOW_SB )
 425             ShowScrollbars(wxSHOW_SB_ALWAYS, wxSHOW_SB_ALWAYS);
 426
 427         return T::Create(parent, winid, pos, size, style, name);
 428 #endif
 429     }
 430
 431 #ifdef __WXMSW__
 432     // we need to return a special WM_GETDLGCODE value to process just the
 433     // arrows but let the other navigation characters through
 434     virtual WXLRESULT MSWWindowProc(WXUINT nMsg, WXWPARAM wParam, WXLPARAM lParam)
 435     {
 436         return FilterMSWWindowProc(nMsg, T::MSWWindowProc(nMsg, wParam, lParam));
 437     }
 438
 439     // Take into account the scroll origin.
 440     virtual void MSWAdjustBrushOrg(int* xOrg, int* yOrg) const
 441     {
 442         CalcUnscrolledPosition(*xOrg, *yOrg, xOrg, yOrg);
 443     }
 444 #endif // __WXMSW__
 445
 446     WX_FORWARD_TO_SCROLL_HELPER()
 447
 448 protected:
 449     virtual wxSize DoGetBestSize() const
 450     {
 451         return FilterBestSize(this, this, T::DoGetBestSize());
 452     }
 453
 454 private:
 455     // VC++ 6 gives warning for the declaration of template member function
 456     // without definition
 457 #ifndef __VISUALC6__
 458     wxDECLARE_NO_COPY_CLASS(wxScrolled);
 459 #endif
 460 };
 461
 462 #ifdef __VISUALC6__
 463     // disable the warning about non dll-interface class used as base for
 464     // dll-interface class: it's harmless in this case
 465     #pragma warning(push)
 466     #pragma warning(disable:4275)
 467 #endif
 468
 469 // for compatibility with existing code, we provide wxScrolledWindow
 470 // "typedef" for wxScrolled<wxPanel>. It's not a real typedef because we
 471 // want wxScrolledWindow to show in wxRTTI information (the class is widely
 472 // used and likelihood of its wxRTTI information being used too is high):
 473 class WXDLLIMPEXP_CORE wxScrolledWindow : public wxScrolled<wxPanel>
 474 {
 475 public:
 476     wxScrolledWindow() : wxScrolled<wxPanel>() {}
 477     wxScrolledWindow(wxWindow *parent,
 478                      wxWindowID winid = wxID_ANY,
 479                      const wxPoint& pos = wxDefaultPosition,
 480                      const wxSize& size = wxDefaultSize,
 481                      long style = wxScrolledWindowStyle,
 482                      const wxString& name = wxPanelNameStr)
 483         : wxScrolled<wxPanel>(parent, winid, pos, size, style, name) {}
 484
 485     DECLARE_DYNAMIC_CLASS_NO_COPY(wxScrolledWindow)
 486 };
 487
 488 typedef wxScrolled<wxWindow> wxScrolledCanvas;
 489
 490 #ifdef __VISUALC6__
 491     #pragma warning(pop)
 492 #endif
 493
 494 #endif // _WX_SCROLWIN_H_BASE_