include/wx/scrolwin.h

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        include/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     virtual void EnableScrolling(bool x_scrolling, bool y_scrolling);
 110
 111     // Get the view start
 112     void GetViewStart(int *x, int *y) const { DoGetViewStart(x, y); }
 113
 114     wxPoint GetViewStart() const
 115     {
 116         wxPoint pt;
 117         DoGetViewStart(&pt.x, &pt.y);
 118         return pt;
 119     }
 120
 121     // Set the scale factor, used in PrepareDC
 122     void SetScale(double xs, double ys) { m_scaleX = xs; m_scaleY = ys; }
 123     double GetScaleX() const { return m_scaleX; }
 124     double GetScaleY() const { return m_scaleY; }
 125
 126     // translate between scrolled and unscrolled coordinates
 127     void CalcScrolledPosition(int x, int y, int *xx, int *yy) const
 128         {  DoCalcScrolledPosition(x, y, xx, yy); }
 129     wxPoint CalcScrolledPosition(const wxPoint& pt) const
 130     {
 131         wxPoint p2;
 132         DoCalcScrolledPosition(pt.x, pt.y, &p2.x, &p2.y);
 133         return p2;
 134     }
 135
 136     void CalcUnscrolledPosition(int x, int y, int *xx, int *yy) const
 137         {  DoCalcUnscrolledPosition(x, y, xx, yy); }
 138     wxPoint CalcUnscrolledPosition(const wxPoint& pt) const
 139     {
 140         wxPoint p2;
 141         DoCalcUnscrolledPosition(pt.x, pt.y, &p2.x, &p2.y);
 142         return p2;
 143     }
 144
 145     void DoCalcScrolledPosition(int x, int y, int *xx, int *yy) const;
 146     void DoCalcUnscrolledPosition(int x, int y, int *xx, int *yy) const;
 147
 148     // Adjust the scrollbars
 149     virtual void AdjustScrollbars() = 0;
 150
 151     // Calculate scroll increment
 152     int CalcScrollInc(wxScrollWinEvent& event);
 153
 154     // Normally the wxScrolledWindow will scroll itself, but in some rare
 155     // occasions you might want it to scroll [part of] another window (e.g. a
 156     // child of it in order to scroll only a portion the area between the
 157     // scrollbars (spreadsheet: only cell area will move).
 158     void SetTargetWindow(wxWindow *target);
 159     wxWindow *GetTargetWindow() const;
 160
 161     void SetTargetRect(const wxRect& rect) { m_rectToScroll = rect; }
 162     wxRect GetTargetRect() const { return m_rectToScroll; }
 163
 164     // Override this function to draw the graphic (or just process EVT_PAINT)
 165     virtual void OnDraw(wxDC& WXUNUSED(dc)) { }
 166
 167     // change the DC origin according to the scroll position.
 168     virtual void DoPrepareDC(wxDC& dc);
 169
 170     // are we generating the autoscroll events?
 171     bool IsAutoScrolling() const { return m_timerAutoScroll != NULL; }
 172
 173     // stop generating the scroll events when mouse is held outside the window
 174     void StopAutoScrolling();
 175
 176     // this method can be overridden in a derived class to forbid sending the
 177     // auto scroll events - note that unlike StopAutoScrolling() it doesn't
 178     // stop the timer, so it will be called repeatedly and will typically
 179     // return different values depending on the current mouse position
 180     //
 181     // the base class version just returns true
 182     virtual bool SendAutoScrollEvents(wxScrollWinEvent& event) const;
 183
 184     // the methods to be called from the window event handlers
 185     void HandleOnScroll(wxScrollWinEvent& event);
 186     void HandleOnSize(wxSizeEvent& event);
 187     void HandleOnPaint(wxPaintEvent& event);
 188     void HandleOnChar(wxKeyEvent& event);
 189     void HandleOnMouseEnter(wxMouseEvent& event);
 190     void HandleOnMouseLeave(wxMouseEvent& event);
 191 #if wxUSE_MOUSEWHEEL
 192     void HandleOnMouseWheel(wxMouseEvent& event);
 193 #endif // wxUSE_MOUSEWHEEL
 194     void HandleOnChildFocus(wxChildFocusEvent& event);
 195
 196 #if WXWIN_COMPATIBILITY_2_8
 197     wxDEPRECATED(
 198         void OnScroll(wxScrollWinEvent& event) { HandleOnScroll(event); }
 199     )
 200 #endif // WXWIN_COMPATIBILITY_2_8
 201
 202 protected:
 203     // get pointer to our scroll rect if we use it or NULL
 204     const wxRect *GetScrollRect() const
 205     {
 206         return m_rectToScroll.width != 0 ? &m_rectToScroll : NULL;
 207     }
 208
 209     // get the size of the target window
 210     wxSize GetTargetSize() const
 211     {
 212         return m_rectToScroll.width != 0 ? m_rectToScroll.GetSize()
 213                                          : m_targetWindow->GetClientSize();
 214     }
 215
 216     void GetTargetSize(int *w, int *h) const
 217     {
 218         wxSize size = GetTargetSize();
 219         if ( w )
 220             *w = size.x;
 221         if ( h )
 222             *h = size.y;
 223     }
 224
 225     // implementation of public methods with the same name
 226     virtual void DoGetViewStart(int *x, int *y) const;
 227     virtual void DoScroll(int x, int y) = 0;
 228     virtual void DoShowScrollbars(wxScrollbarVisibility horz,
 229                                   wxScrollbarVisibility vert) = 0;
 230
 231     // implementations of various wxWindow virtual methods which should be
 232     // forwarded to us (this can be done by WX_FORWARD_TO_SCROLL_HELPER())
 233     bool ScrollLayout();
 234     void ScrollDoSetVirtualSize(int x, int y);
 235     wxSize ScrollGetBestVirtualSize() const;
 236
 237     // change just the target window (unlike SetWindow which changes m_win as
 238     // well)
 239     void DoSetTargetWindow(wxWindow *target);
 240
 241     // delete the event handler we installed
 242     void DeleteEvtHandler();
 243
 244     // calls wxScrollHelperEvtHandler::ResetDrawnFlag(), see explanation
 245     // in wxScrollHelperEvtHandler::ProcessEvent()
 246     void ResetDrawnFlag();
 247
 248     // this function should be overridden to return the size available for
 249     // m_targetWindow inside m_win of the given size
 250     //
 251     // the default implementation is only good for m_targetWindow == m_win
 252     // case, if we're scrolling a subwindow you must override this method
 253     virtual wxSize GetSizeAvailableForScrollTarget(const wxSize& size)
 254     {
 255         // returning just size from here is wrong but it was decided that it is
 256         // not wrong enough to break the existing code (which doesn't override
 257         // this recently added function at all) by adding this assert
 258         //
 259         // wxASSERT_MSG( m_targetWindow == m_win, "must be overridden" );
 260
 261         return size;
 262     }
 263
 264
 265     double                m_scaleX;
 266     double                m_scaleY;
 267
 268     wxWindow             *m_win,
 269                          *m_targetWindow;
 270
 271     wxRect                m_rectToScroll;
 272
 273     wxTimer              *m_timerAutoScroll;
 274
 275     int                   m_xScrollPixelsPerLine;
 276     int                   m_yScrollPixelsPerLine;
 277     int                   m_xScrollPosition;
 278     int                   m_yScrollPosition;
 279     int                   m_xScrollLines;
 280     int                   m_yScrollLines;
 281     int                   m_xScrollLinesPerPage;
 282     int                   m_yScrollLinesPerPage;
 283
 284     bool                  m_xScrollingEnabled;
 285     bool                  m_yScrollingEnabled;
 286
 287 #if wxUSE_MOUSEWHEEL
 288     int m_wheelRotation;
 289 #endif // wxUSE_MOUSEWHEEL
 290
 291     wxScrollHelperEvtHandler *m_handler;
 292
 293     wxDECLARE_NO_COPY_CLASS(wxScrollHelperBase);
 294 };
 295
 296 // this macro can be used in a wxScrollHelper-derived class to forward wxWindow
 297 // methods to corresponding wxScrollHelper methods
 298 #define WX_FORWARD_TO_SCROLL_HELPER()                                         \
 299 public:                                                                       \
 300     virtual void PrepareDC(wxDC& dc) { DoPrepareDC(dc); }                     \
 301     virtual bool Layout() { return ScrollLayout(); }                          \
 302     virtual void DoSetVirtualSize(int x, int y)                               \
 303         { ScrollDoSetVirtualSize(x, y); }                                     \
 304     virtual wxSize GetBestVirtualSize() const                                 \
 305         { return ScrollGetBestVirtualSize(); }
 306
 307 // include the declaration of the real wxScrollHelper
 308 #if defined(__WXGTK20__) && !defined(__WXUNIVERSAL__)
 309     #include "wx/gtk/scrolwin.h"
 310 #elif defined(__WXGTK__) && !defined(__WXUNIVERSAL__)
 311     #include "wx/gtk1/scrolwin.h"
 312 #else
 313     #define wxHAS_GENERIC_SCROLLWIN
 314     #include "wx/generic/scrolwin.h"
 315 #endif
 316
 317 // ----------------------------------------------------------------------------
 318 // wxScrolled<T>: a wxWindow which knows how to scroll
 319 // ----------------------------------------------------------------------------
 320
 321 // helper class for wxScrolled<T> below
 322 struct WXDLLIMPEXP_CORE wxScrolledT_Helper
 323 {
 324     static wxSize FilterBestSize(const wxWindow *win,
 325                                  const wxScrollHelper *helper,
 326                                  const wxSize& origBest);
 327 #ifdef __WXMSW__
 328     static WXLRESULT FilterMSWWindowProc(WXUINT nMsg, WXLRESULT origResult);
 329 #endif
 330 };
 331
 332 // Scrollable window base on window type T. This used to be wxScrolledWindow,
 333 // but wxScrolledWindow includes wxControlContainer functionality and that's
 334 // not always desirable.
 335 template<class T>
 336 class wxScrolled : public T,
 337                    public wxScrollHelper,
 338                    private wxScrolledT_Helper
 339 {
 340 public:
 341     wxScrolled() : wxScrollHelper(this) { }
 342     wxScrolled(wxWindow *parent,
 343                wxWindowID winid = wxID_ANY,
 344                const wxPoint& pos = wxDefaultPosition,
 345                const wxSize& size = wxDefaultSize,
 346                long style = wxScrolledWindowStyle,
 347                const wxString& name = wxPanelNameStr)
 348         : wxScrollHelper(this)
 349     {
 350         Create(parent, winid, pos, size, style, name);
 351     }
 352
 353     bool Create(wxWindow *parent,
 354                 wxWindowID winid,
 355                 const wxPoint& pos = wxDefaultPosition,
 356                 const wxSize& size = wxDefaultSize,
 357                 long style = wxScrolledWindowStyle,
 358                 const wxString& name = wxPanelNameStr)
 359     {
 360         m_targetWindow = this;
 361
 362 #ifdef __WXMAC__
 363         this->MacSetClipChildren(true);
 364 #endif
 365
 366         this->Connect(wxEVT_PAINT, wxPaintEventHandler(wxScrolled::OnPaint));
 367
 368         // by default, we're scrollable in both directions (but if one of the
 369         // styles is specified explicitly, we shouldn't add the other one
 370         // automatically)
 371         if ( !(style & (wxHSCROLL | wxVSCROLL)) )
 372             style |= wxHSCROLL | wxVSCROLL;
 373
 374         return T::Create(parent, winid, pos, size, style, name);
 375     }
 376
 377     // we need to return a special WM_GETDLGCODE value to process just the
 378     // arrows but let the other navigation characters through
 379 #ifdef __WXMSW__
 380     virtual WXLRESULT MSWWindowProc(WXUINT nMsg, WXWPARAM wParam, WXLPARAM lParam)
 381     {
 382         return FilterMSWWindowProc(nMsg, T::MSWWindowProc(nMsg, wParam, lParam));
 383     }
 384 #endif // __WXMSW__
 385
 386     WX_FORWARD_TO_SCROLL_HELPER()
 387
 388 protected:
 389     virtual wxSize DoGetBestSize() const
 390     {
 391         return FilterBestSize(this, this, T::DoGetBestSize());
 392     }
 393
 394 private:
 395     // this is needed for wxEVT_PAINT processing hack described in
 396     // wxScrollHelperEvtHandler::ProcessEvent()
 397     void OnPaint(wxPaintEvent& event)
 398     {
 399         // the user code didn't really draw the window if we got here, so set
 400         // this flag to try to call OnDraw() later
 401         ResetDrawnFlag();
 402         event.Skip();
 403     }
 404
 405     // VC++ 6 gives warning for the declaration of template member function
 406     // without definition
 407 #if !defined(__VISUALC__) || wxCHECK_VISUALC_VERSION(7)
 408     wxDECLARE_NO_COPY_CLASS(wxScrolled);
 409 #endif
 410 };
 411
 412 // for compatibility with existing code, we provide wxScrolledWindow
 413 // "typedef" for wxScrolled<wxPanel>. It's not a real typedef because we
 414 // want wxScrolledWindow to show in wxRTTI information (the class is widely
 415 // used and likelihood of its wxRTTI information being used too is high):
 416 class WXDLLIMPEXP_CORE wxScrolledWindow : public wxScrolled<wxPanel>
 417 {
 418 public:
 419     wxScrolledWindow() : wxScrolled<wxPanel>() {}
 420     wxScrolledWindow(wxWindow *parent,
 421                      wxWindowID winid = wxID_ANY,
 422                      const wxPoint& pos = wxDefaultPosition,
 423                      const wxSize& size = wxDefaultSize,
 424                      long style = wxScrolledWindowStyle,
 425                      const wxString& name = wxPanelNameStr)
 426         : wxScrolled<wxPanel>(parent, winid, pos, size, style, name) {}
 427
 428     DECLARE_DYNAMIC_CLASS_NO_COPY(wxScrolledWindow)
 429 };
 430
 431 typedef wxScrolled<wxWindow> wxScrolledCanvas;
 432
 433 #endif // _WX_SCROLWIN_H_BASE_