include/wx/msw/dragimag.h

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        wx/msw/dragimag.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:     08/04/99
   8 // RCS-ID:      $Id$
   9 // Copyright:   (c) Julian Smart
  10 // Licence:     wxWindows licence
  11 /////////////////////////////////////////////////////////////////////////////
  12
  13 #ifndef _WX_DRAGIMAG_H_
  14 #define _WX_DRAGIMAG_H_
  15
  16 #ifdef __GNUG__
  17 #pragma interface "dragimag.h"
  18 #endif
  19
  20 #include "wx/bitmap.h"
  21 #include "wx/icon.h"
  22 #include "wx/cursor.h"
  23 #include "wx/treectrl.h"
  24 #include "wx/listctrl.h"
  25
  26 // If 1, use a simple wxCursor instead of ImageList_SetDragCursorImage,
  27 // and some other simplifications
  28 #define wxUSE_SIMPLER_DRAGIMAGE 1
  29
  30 /*
  31   To use this class, create a wxDragImage when you start dragging, for example:
  32
  33   void MyTreeCtrl::OnBeginDrag(wxTreeEvent& event)
  34   {
  35 #ifdef __WXMSW__
  36     ::UpdateWindow((HWND) GetHWND()); // We need to implement this in wxWindows
  37 #endif
  38
  39     CaptureMouse();
  40
  41     m_dragImage = new wxDragImage(* this, itemId);
  42     m_dragImage->BeginDrag(wxPoint(0, 0), this);
  43     m_dragImage->Move(pt, this);
  44     m_dragImage->Show(this);
  45     ...
  46   }
  47
  48   In your OnMouseMove function, hide the image, do any display updating required,
  49   then move and show the image again:
  50
  51   void MyTreeCtrl::OnMouseMove(wxMouseEvent& event)
  52   {
  53     if (m_dragMode == MY_TREE_DRAG_NONE)
  54     {
  55         event.Skip();
  56         return;
  57     }
  58
  59     // Prevent screen corruption by hiding the image
  60     if (m_dragImage)
  61         m_dragImage->Hide(this);
  62
  63     // Do some updating of the window, such as highlighting the drop target
  64     ...
  65
  66 #ifdef __WXMSW__
  67     if (updateWindow)
  68         ::UpdateWindow((HWND) GetHWND());
  69 #endif
  70
  71     // Move and show the image again
  72     m_dragImage->Move(event.GetPosition(), this);
  73     m_dragImage->Show(this);
  74  }
  75
  76  Eventually we end the drag and delete the drag image.
  77
  78  void MyTreeCtrl::OnLeftUp(wxMouseEvent& event)
  79  {
  80     ...
  81
  82     // End the drag and delete the drag image
  83     if (m_dragImage)
  84     {
  85         m_dragImage->EndDrag(this);
  86         delete m_dragImage;
  87         m_dragImage = NULL;
  88     }
  89     ReleaseMouse();
  90  }
  91 */
  92
  93 /*
  94  Notes for Unix version:
  95  Can we simply use cursors instead, creating a cursor dynamically, setting it into the window
  96  in BeginDrag, and restoring the old cursor in EndDrag?
  97  For a really bog-standard implementation, we could simply use a normal dragging cursor
  98  and ignore the image.
  99 */
 100
 101 /*
 102  * wxDragImage
 103  */
 104
 105 class WXDLLEXPORT wxDragImage: public wxObject
 106 {
 107 public:
 108
 109     // Ctors & dtor
 110     ////////////////////////////////////////////////////////////////////////////
 111
 112     wxDragImage();
 113     wxDragImage(const wxBitmap& image, const wxCursor& cursor = wxNullCursor, const wxPoint& cursorHotspot = wxPoint(0, 0))
 114     {
 115         Init();
 116
 117         Create(image, cursor, cursorHotspot);
 118     }
 119     wxDragImage(const wxIcon& image, const wxCursor& cursor = wxNullCursor, const wxPoint& cursorHotspot = wxPoint(0, 0))
 120     {
 121         Init();
 122
 123         Create(image, cursor, cursorHotspot);
 124     }
 125     wxDragImage(const wxString& str, const wxCursor& cursor = wxNullCursor, const wxPoint& cursorHotspot = wxPoint(0, 0))
 126     {
 127         Init();
 128
 129         Create(str, cursor, cursorHotspot);
 130     }
 131     wxDragImage(const wxTreeCtrl& treeCtrl, wxTreeItemId& id)
 132     {
 133         Init();
 134
 135         Create(treeCtrl, id);
 136     }
 137     wxDragImage(const wxListCtrl& listCtrl, long id)
 138     {
 139         Init();
 140
 141         Create(listCtrl, id);
 142     }
 143     ~wxDragImage();
 144
 145     // Attributes
 146     ////////////////////////////////////////////////////////////////////////////
 147
 148     // Operations
 149     ////////////////////////////////////////////////////////////////////////////
 150
 151     // Create a drag image from a bitmap and optional cursor
 152     bool Create(const wxBitmap& image, const wxCursor& cursor = wxNullCursor, const wxPoint& cursorHotspot = wxPoint(0, 0));
 153
 154     // Create a drag image from an icon and optional cursor
 155     bool Create(const wxIcon& image, const wxCursor& cursor = wxNullCursor, const wxPoint& cursorHotspot = wxPoint(0, 0));
 156
 157     // Create a drag image from a string and optional cursor
 158     bool Create(const wxString& str, const wxCursor& cursor = wxNullCursor, const wxPoint& cursorHotspot = wxPoint(0, 0));
 159
 160     // Create a drag image for the given tree control item
 161     bool Create(const wxTreeCtrl& treeCtrl, wxTreeItemId& id);
 162
 163     // Create a drag image for the given list control item
 164     bool Create(const wxListCtrl& listCtrl, long id);
 165
 166     // Begin drag. hotspot is the location of the drag position relative to the upper-left
 167     // corner of the image.
 168     bool BeginDrag(const wxPoint& hotspot, wxWindow* window, bool fullScreen = FALSE, wxRect* rect = (wxRect*) NULL);
 169
 170     // Begin drag. hotspot is the location of the drag position relative to the upper-left
 171     // corner of the image. This is full screen only. fullScreenRect gives the
 172     // position of the window on the screen, to restrict the drag to.
 173     bool BeginDrag(const wxPoint& hotspot, wxWindow* window, wxWindow* fullScreenRect);
 174
 175     // End drag
 176     bool EndDrag();
 177
 178     // Move the image: call from OnMouseMove. Pt is in window client coordinates if window
 179     // is non-NULL, or in screen coordinates if NULL.
 180     bool Move(const wxPoint& pt);
 181
 182     // Show the image
 183     bool Show();
 184
 185     // Hide the image
 186     bool Hide();
 187
 188     // Implementation
 189     ////////////////////////////////////////////////////////////////////////////
 190
 191     // Initialize variables
 192     void Init();
 193
 194     // Returns the native image list handle
 195     WXHIMAGELIST GetHIMAGELIST() const { return m_hImageList; }
 196
 197 #if !wxUSE_SIMPLER_DRAGIMAGE
 198     // Returns the native image list handle for the cursor
 199     WXHIMAGELIST GetCursorHIMAGELIST() const { return m_hCursorImageList; }
 200 #endif
 201
 202 protected:
 203     WXHIMAGELIST    m_hImageList;
 204
 205 #if wxUSE_SIMPLER_DRAGIMAGE
 206     wxCursor        m_oldCursor;
 207 #else
 208     WXHIMAGELIST    m_hCursorImageList;
 209 #endif
 210
 211     wxCursor        m_cursor;
 212     wxPoint         m_cursorHotspot;
 213     wxPoint         m_position;
 214     wxWindow*       m_window;
 215     wxRect          m_boundingRect;
 216     bool            m_fullScreen;
 217
 218 private:
 219     DECLARE_DYNAMIC_CLASS(wxDragImage)
 220 };
 221
 222 #endif
 223     // _WX_DRAGIMAG_H_