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