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 /*
  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 WXDLLEXPORT 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     ~wxGenericDragImage();
 155
 156     // Attributes
 157     ////////////////////////////////////////////////////////////////////////////
 158
 159     // For efficiency, tell wxGenericDragImage to use a bitmap that's already
 160     // created (e.g. from last drag)
 161     void SetBackingBitmap(wxBitmap* bitmap) { m_pBackingBitmap = bitmap; }
 162
 163     // Operations
 164     ////////////////////////////////////////////////////////////////////////////
 165
 166     // Create a drag image with a virtual image (need to override DoDrawImage, GetImageRect)
 167     bool Create(const wxCursor& cursor = wxNullCursor);
 168
 169     // Create a drag image from a bitmap and optional cursor
 170     bool Create(const wxBitmap& image, const wxCursor& cursor = wxNullCursor);
 171
 172     // Create a drag image from an icon and optional cursor
 173     bool Create(const wxIcon& image, const wxCursor& cursor = wxNullCursor);
 174
 175     // Create a drag image from a string and optional cursor
 176     bool Create(const wxString& str, const wxCursor& cursor = wxNullCursor);
 177
 178 #if wxUSE_TREECTRL
 179     // Create a drag image for the given tree control item
 180     bool Create(const wxTreeCtrl& treeCtrl, wxTreeItemId& id);
 181 #endif
 182
 183 #if wxUSE_LISTCTRL
 184     // Create a drag image for the given list control item
 185     bool Create(const wxListCtrl& listCtrl, long id);
 186 #endif
 187
 188     // Begin drag. hotspot is the location of the drag position relative to the upper-left
 189     // corner of the image.
 190     bool BeginDrag(const wxPoint& hotspot, wxWindow* window, bool fullScreen = false, wxRect* rect = (wxRect*) NULL);
 191
 192     // Begin drag. hotspot is the location of the drag position relative to the upper-left
 193     // corner of the image. This is full screen only. fullScreenRect gives the
 194     // position of the window on the screen, to restrict the drag to.
 195     bool BeginDrag(const wxPoint& hotspot, wxWindow* window, wxWindow* fullScreenRect);
 196
 197     // End drag
 198     bool EndDrag();
 199
 200     // Move the image: call from OnMouseMove. Pt is in window client coordinates if window
 201     // is non-NULL, or in screen coordinates if NULL.
 202     bool Move(const wxPoint& pt);
 203
 204     // Show the image
 205     bool Show();
 206
 207     // Hide the image
 208     bool Hide();
 209
 210     // Implementation
 211     ////////////////////////////////////////////////////////////////////////////
 212
 213     void Init();
 214
 215     // Override this if you are using a virtual image (drawing your own image)
 216     virtual wxRect GetImageRect(const wxPoint& pos) const;
 217
 218     // Override this if you are using a virtual image (drawing your own image)
 219     virtual bool DoDrawImage(wxDC& dc, const wxPoint& pos) const;
 220
 221     // Override this if you wish to draw the window contents to the backing bitmap
 222     // yourself. This can be desirable if you wish to avoid flicker by not having to
 223     // redraw the window itself before dragging in order to be graphic-minus-dragged-objects.
 224     // Instead, paint the drag image's backing bitmap to be correct, and leave the window
 225     // to be updated only when dragging the objects away (thus giving a smoother appearance).
 226     virtual bool UpdateBackingFromWindow(wxDC& windowDC, wxMemoryDC& destDC,
 227                                          const wxRect& sourceRect, const wxRect& destRect) const;
 228
 229     // Erase and redraw simultaneously if possible
 230     virtual bool RedrawImage(const wxPoint& oldPos, const wxPoint& newPos, bool eraseOld, bool drawNew);
 231
 232 protected:
 233     wxBitmap        m_bitmap;
 234     wxIcon          m_icon;
 235     wxCursor        m_cursor;
 236     wxCursor        m_oldCursor;
 237 //    wxPoint         m_hotspot;
 238     wxPoint         m_offset; // The hostpot value passed to BeginDrag
 239     wxPoint         m_position;
 240     bool            m_isDirty;
 241     bool            m_isShown;
 242     wxWindow*       m_window;
 243     wxDC*           m_windowDC;
 244
 245     // Stores the window contents while we're dragging the image around
 246     wxBitmap        m_backingBitmap;
 247     wxBitmap*       m_pBackingBitmap; // Pointer to existing backing bitmap
 248                                       // (pass to wxGenericDragImage as an efficiency measure)
 249     // A temporary bitmap for repairing/redrawing
 250     wxBitmap        m_repairBitmap;
 251
 252     wxRect          m_boundingRect;
 253     bool            m_fullScreen;
 254
 255 private:
 256     DECLARE_DYNAMIC_CLASS(wxGenericDragImage)
 257     DECLARE_NO_COPY_CLASS(wxGenericDragImage)
 258 };
 259
 260 #endif
 261     // _WX_DRAGIMGG_H_