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