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