include/wx/generic/dragimgg.h

   1 //////////////////////////////////////////////////////////////////////////////
   2 // Name:        wx/generic/dragimgg.h
   3 // Purpose:     wxDragImage class: a kind of a cursor, that can cope
   4 //              with more sophisticated images
   5 // Author:      Julian Smart
   6 // Modified by:
   7 // Created:     29/2/2000
   8 // RCS-ID:      $Id$
   9 // Copyright:   (c) Julian Smart
  10 // Licence:     wxWindows licence
  11 /////////////////////////////////////////////////////////////////////////////
  12
  13 #ifndef _WX_DRAGIMGG_H_
  14 #define _WX_DRAGIMGG_H_
  15
  16 #include "wx/bitmap.h"
  17 #include "wx/icon.h"
  18 #include "wx/cursor.h"
  19 #include "wx/treectrl.h"
  20 #include "wx/listctrl.h"
  21 #include "wx/log.h"
  22
  23 #if defined(wxMAC_USE_CORE_GRAPHICS) && wxMAC_USE_CORE_GRAPHICS
  24 #include "wx/dc.h"
  25 #endif
  26
  27 /*
  28   To use this class, create a wxDragImage when you start dragging, for example:
  29
  30   void MyTreeCtrl::OnBeginDrag(wxTreeEvent& event)
  31   {
  32 #ifdef __WXMSW__
  33     ::UpdateWindow((HWND) GetHWND()); // We need to implement this in wxWidgets
  34 #endif
  35
  36     CaptureMouse();
  37
  38     m_dragImage = new wxDragImage(* this, itemId);
  39     m_dragImage->BeginDrag(wxPoint(0, 0), this);
  40     m_dragImage->Move(pt, this);
  41     m_dragImage->Show(this);
  42     ...
  43   }
  44
  45   In your OnMouseMove function, hide the image, do any display updating required,
  46   then move and show the image again:
  47
  48   void MyTreeCtrl::OnMouseMove(wxMouseEvent& event)
  49   {
  50     if (m_dragMode == MY_TREE_DRAG_NONE)
  51     {
  52         event.Skip();
  53         return;
  54     }
  55
  56     // Prevent screen corruption by hiding the image
  57     if (m_dragImage)
  58         m_dragImage->Hide(this);
  59
  60     // Do some updating of the window, such as highlighting the drop target
  61     ...
  62
  63 #ifdef __WXMSW__
  64     if (updateWindow)
  65         ::UpdateWindow((HWND) GetHWND());
  66 #endif
  67
  68     // Move and show the image again
  69     m_dragImage->Move(event.GetPosition(), this);
  70     m_dragImage->Show(this);
  71  }
  72
  73  Eventually we end the drag and delete the drag image.
  74
  75  void MyTreeCtrl::OnLeftUp(wxMouseEvent& event)
  76  {
  77     ...
  78
  79     // End the drag and delete the drag image
  80     if (m_dragImage)
  81     {
  82         m_dragImage->EndDrag(this);
  83         delete m_dragImage;
  84         m_dragImage = NULL;
  85     }
  86     ReleaseMouse();
  87  }
  88 */
  89
  90 /*
  91  * wxGenericDragImage
  92  */
  93
  94 class WXDLLEXPORT wxGenericDragImage: public wxObject
  95 {
  96 public:
  97
  98     // Ctors & dtor
  99     ////////////////////////////////////////////////////////////////////////////
 100
 101     wxGenericDragImage(const wxCursor& cursor = wxNullCursor)
 102     {
 103         Init();
 104         Create(cursor);
 105     }
 106
 107     wxGenericDragImage(const wxBitmap& image, const wxCursor& cursor = wxNullCursor)
 108     {
 109         Init();
 110
 111         Create(image, cursor);
 112     }
 113
 114     wxGenericDragImage(const wxIcon& image, const wxCursor& cursor = wxNullCursor)
 115     {
 116         Init();
 117
 118         Create(image, cursor);
 119     }
 120
 121     wxGenericDragImage(const wxString& str, const wxCursor& cursor = wxNullCursor)
 122     {
 123         Init();
 124
 125         Create(str, cursor);
 126     }
 127
 128 #if WXWIN_COMPATIBILITY_2_6
 129     // don't use in new code, use versions without hot spot parameter
 130     wxDEPRECATED( wxGenericDragImage(const wxCursor& cursor, const wxPoint& cursorHotspot) );
 131     wxDEPRECATED( wxGenericDragImage(const wxBitmap& image, const wxCursor& cursor, const wxPoint& cursorHotspot) );
 132     wxDEPRECATED( wxGenericDragImage(const wxIcon& image, const wxCursor& cursor, const wxPoint& cursorHotspot) );
 133     wxDEPRECATED( wxGenericDragImage(const wxString& str, const wxCursor& cursor, const wxPoint& cursorHotspot) );
 134     wxDEPRECATED( bool Create(const wxCursor& cursor, const wxPoint& cursorHotspot) );
 135     wxDEPRECATED( bool Create(const wxBitmap& image, const wxCursor& cursor, const wxPoint& cursorHotspot) );
 136     wxDEPRECATED( bool Create(const wxIcon& image, const wxCursor& cursor, const wxPoint& cursorHotspot) );
 137     wxDEPRECATED( bool Create(const wxString& str, const wxCursor& cursor, const wxPoint& cursorHotspot) );
 138 #endif // WXWIN_COMPATIBILITY_2_6
 139
 140 #if wxUSE_TREECTRL
 141     wxGenericDragImage(const wxTreeCtrl& treeCtrl, wxTreeItemId& id)
 142     {
 143         Init();
 144
 145         Create(treeCtrl, id);
 146     }
 147 #endif
 148
 149 #if wxUSE_LISTCTRL
 150     wxGenericDragImage(const wxListCtrl& listCtrl, long id)
 151     {
 152         Init();
 153
 154         Create(listCtrl, id);
 155     }
 156 #endif
 157
 158     virtual ~wxGenericDragImage();
 159
 160     // Attributes
 161     ////////////////////////////////////////////////////////////////////////////
 162
 163     // For efficiency, tell wxGenericDragImage to use a bitmap that's already
 164     // created (e.g. from last drag)
 165     void SetBackingBitmap(wxBitmap* bitmap) {
 166 #if defined(wxMAC_USE_CORE_GRAPHICS) && wxMAC_USE_CORE_GRAPHICS
 167 #else
 168         m_pBackingBitmap = bitmap;
 169 #endif
 170     }
 171
 172     // Operations
 173     ////////////////////////////////////////////////////////////////////////////
 174
 175     // Create a drag image with a virtual image (need to override DoDrawImage, GetImageRect)
 176     bool Create(const wxCursor& cursor = wxNullCursor);
 177
 178     // Create a drag image from a bitmap and optional cursor
 179     bool Create(const wxBitmap& image, const wxCursor& cursor = wxNullCursor);
 180
 181     // Create a drag image from an icon and optional cursor
 182     bool Create(const wxIcon& image, const wxCursor& cursor = wxNullCursor);
 183
 184     // Create a drag image from a string and optional cursor
 185     bool Create(const wxString& str, const wxCursor& cursor = wxNullCursor);
 186
 187 #if wxUSE_TREECTRL
 188     // Create a drag image for the given tree control item
 189     bool Create(const wxTreeCtrl& treeCtrl, wxTreeItemId& id);
 190 #endif
 191
 192 #if wxUSE_LISTCTRL
 193     // Create a drag image for the given list control item
 194     bool Create(const wxListCtrl& listCtrl, long id);
 195 #endif
 196
 197     // Begin drag. hotspot is the location of the drag position relative to the upper-left
 198     // corner of the image.
 199     bool BeginDrag(const wxPoint& hotspot, wxWindow* window, bool fullScreen = false, wxRect* rect = (wxRect*) NULL);
 200
 201     // Begin drag. hotspot is the location of the drag position relative to the upper-left
 202     // corner of the image. This is full screen only. fullScreenRect gives the
 203     // position of the window on the screen, to restrict the drag to.
 204     bool BeginDrag(const wxPoint& hotspot, wxWindow* window, wxWindow* fullScreenRect);
 205
 206     // End drag
 207     bool EndDrag();
 208
 209     // Move the image: call from OnMouseMove. Pt is in window client coordinates if window
 210     // is non-NULL, or in screen coordinates if NULL.
 211     bool Move(const wxPoint& pt);
 212
 213     // Show the image
 214     bool Show();
 215
 216     // Hide the image
 217     bool Hide();
 218
 219     // Implementation
 220     ////////////////////////////////////////////////////////////////////////////
 221
 222     void Init();
 223
 224     // Override this if you are using a virtual image (drawing your own image)
 225     virtual wxRect GetImageRect(const wxPoint& pos) const;
 226
 227     // Override this if you are using a virtual image (drawing your own image)
 228     virtual bool DoDrawImage(wxDC& dc, const wxPoint& pos) const;
 229
 230     // Override this if you wish to draw the window contents to the backing bitmap
 231     // yourself. This can be desirable if you wish to avoid flicker by not having to
 232     // redraw the window itself before dragging in order to be graphic-minus-dragged-objects.
 233     // Instead, paint the drag image's backing bitmap to be correct, and leave the window
 234     // to be updated only when dragging the objects away (thus giving a smoother appearance).
 235     virtual bool UpdateBackingFromWindow(wxDC& windowDC, wxMemoryDC& destDC,
 236                                          const wxRect& sourceRect, const wxRect& destRect) const;
 237
 238     // Erase and redraw simultaneously if possible
 239     virtual bool RedrawImage(const wxPoint& oldPos, const wxPoint& newPos, bool eraseOld, bool drawNew);
 240
 241 protected:
 242     wxBitmap        m_bitmap;
 243     wxIcon          m_icon;
 244     wxCursor        m_cursor;
 245     wxCursor        m_oldCursor;
 246 //    wxPoint         m_hotspot;
 247     wxPoint         m_offset; // The hostpot value passed to BeginDrag
 248     wxPoint         m_position;
 249     bool            m_isDirty;
 250     bool            m_isShown;
 251     wxWindow*       m_window;
 252     wxDC*           m_windowDC;
 253
 254 #if defined(wxMAC_USE_CORE_GRAPHICS) && wxMAC_USE_CORE_GRAPHICS
 255     wxOverlay       m_overlay;
 256     wxDCOverlay*     m_dcOverlay;
 257 #else
 258     // Stores the window contents while we're dragging the image around
 259     wxBitmap        m_backingBitmap;
 260     wxBitmap*       m_pBackingBitmap; // Pointer to existing backing bitmap
 261                                       // (pass to wxGenericDragImage as an efficiency measure)
 262     // A temporary bitmap for repairing/redrawing
 263     wxBitmap        m_repairBitmap;
 264 #endif
 265
 266     wxRect          m_boundingRect;
 267     bool            m_fullScreen;
 268
 269 private:
 270     DECLARE_DYNAMIC_CLASS(wxGenericDragImage)
 271     DECLARE_NO_COPY_CLASS(wxGenericDragImage)
 272 };
 273
 274 #endif
 275     // _WX_DRAGIMGG_H_