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