///////////////////////////////////////////////////////////////////////////// // Name: wx/msw/dragimag.h // Purpose: wxDragImage class: a kind of a cursor, that can cope // with more sophisticated images // Author: Julian Smart // Modified by: // Created: 08/04/99 // RCS-ID: $Id$ // Copyright: (c) Julian Smart // Licence: wxWindows licence ///////////////////////////////////////////////////////////////////////////// #ifndef _WX_DRAGIMAG_H_ #define _WX_DRAGIMAG_H_ #ifdef __GNUG__ #pragma interface "dragimag.h" #endif #include "wx/bitmap.h" #include "wx/icon.h" #include "wx/cursor.h" #include "wx/treectrl.h" #include "wx/listctrl.h" // If 1, use a simple wxCursor instead of ImageList_SetDragCursorImage #define wxUSE_SIMPLER_DRAGIMAGE 0 /* To use this class, create a wxDragImage when you start dragging, for example: void MyTreeCtrl::OnBeginDrag(wxTreeEvent& event) { #ifdef __WXMSW__ ::UpdateWindow((HWND) GetHWND()); // We need to implement this in wxWindows #endif CaptureMouse(); m_dragImage = new wxDragImage(* this, itemId); m_dragImage->BeginDrag(wxPoint(0, 0), this); m_dragImage->Move(pt, this); m_dragImage->Show(this); ... } In your OnMouseMove function, hide the image, do any display updating required, then move and show the image again: void MyTreeCtrl::OnMouseMove(wxMouseEvent& event) { if (m_dragMode == MY_TREE_DRAG_NONE) { event.Skip(); return; } // Prevent screen corruption by hiding the image if (m_dragImage) m_dragImage->Hide(this); // Do some updating of the window, such as highlighting the drop target ... #ifdef __WXMSW__ if (updateWindow) ::UpdateWindow((HWND) GetHWND()); #endif // Move and show the image again m_dragImage->Move(event.GetPosition(), this); m_dragImage->Show(this); } Eventually we end the drag and delete the drag image. void MyTreeCtrl::OnLeftUp(wxMouseEvent& event) { ... // End the drag and delete the drag image if (m_dragImage) { m_dragImage->EndDrag(this); delete m_dragImage; m_dragImage = NULL; } ReleaseMouse(); } */ /* Notes for Unix version: Can we simply use cursors instead, creating a cursor dynamically, setting it into the window in BeginDrag, and restoring the old cursor in EndDrag? For a really bog-standard implementation, we could simply use a normal dragging cursor and ignore the image. */ /* * wxDragImage */ class WXDLLEXPORT wxDragImage: public wxObject { public: // Ctors & dtor //////////////////////////////////////////////////////////////////////////// wxDragImage(); wxDragImage(const wxBitmap& image, const wxCursor& cursor = wxNullCursor) { Init(); Create(image, cursor); } // Deprecated form of the above wxDragImage(const wxBitmap& image, const wxCursor& cursor, const wxPoint& cursorHotspot) { Init(); Create(image, cursor, cursorHotspot); } wxDragImage(const wxIcon& image, const wxCursor& cursor = wxNullCursor) { Init(); Create(image, cursor); } // Deprecated form of the above wxDragImage(const wxIcon& image, const wxCursor& cursor, const wxPoint& cursorHotspot) { Init(); Create(image, cursor, cursorHotspot); } wxDragImage(const wxString& str, const wxCursor& cursor = wxNullCursor) { Init(); Create(str, cursor); } // Deprecated form of the above wxDragImage(const wxString& str, const wxCursor& cursor, const wxPoint& cursorHotspot) { Init(); Create(str, cursor, cursorHotspot); } wxDragImage(const wxTreeCtrl& treeCtrl, wxTreeItemId& id) { Init(); Create(treeCtrl, id); } wxDragImage(const wxListCtrl& listCtrl, long id) { Init(); Create(listCtrl, id); } ~wxDragImage(); // Attributes //////////////////////////////////////////////////////////////////////////// // Operations //////////////////////////////////////////////////////////////////////////// // Create a drag image from a bitmap and optional cursor bool Create(const wxBitmap& image, const wxCursor& cursor = wxNullCursor); bool Create(const wxBitmap& image, const wxCursor& cursor, const wxPoint& WXUNUSED(cursorHotspot)) { wxLogDebug(wxT("wxDragImage::Create: use of a cursor hotspot is now deprecated. Please omit this argument.")); return Create(image, cursor); } // Create a drag image from an icon and optional cursor bool Create(const wxIcon& image, const wxCursor& cursor = wxNullCursor); bool Create(const wxIcon& image, const wxCursor& cursor, const wxPoint& WXUNUSED(cursorHotspot)) { wxLogDebug(wxT("wxDragImage::Create: use of a cursor hotspot is now deprecated. Please omit this argument.")); return Create(image, cursor); } // Create a drag image from a string and optional cursor bool Create(const wxString& str, const wxCursor& cursor = wxNullCursor); bool Create(const wxString& str, const wxCursor& cursor, const wxPoint& WXUNUSED(cursorHotspot)) { wxLogDebug(wxT("wxDragImage::Create: use of a cursor hotspot is now deprecated. Please omit this argument.")); return Create(str, cursor); } // Create a drag image for the given tree control item bool Create(const wxTreeCtrl& treeCtrl, wxTreeItemId& id); // Create a drag image for the given list control item bool Create(const wxListCtrl& listCtrl, long id); // Begin drag. hotspot is the location of the drag position relative to the upper-left // corner of the image. bool BeginDrag(const wxPoint& hotspot, wxWindow* window, bool fullScreen = FALSE, wxRect* rect = (wxRect*) NULL); // Begin drag. hotspot is the location of the drag position relative to the upper-left // corner of the image. This is full screen only. fullScreenRect gives the // position of the window on the screen, to restrict the drag to. bool BeginDrag(const wxPoint& hotspot, wxWindow* window, wxWindow* fullScreenRect); // End drag bool EndDrag(); // Move the image: call from OnMouseMove. Pt is in window client coordinates if window // is non-NULL, or in screen coordinates if NULL. bool Move(const wxPoint& pt); // Show the image bool Show(); // Hide the image bool Hide(); // Implementation //////////////////////////////////////////////////////////////////////////// // Initialize variables void Init(); // Returns the native image list handle WXHIMAGELIST GetHIMAGELIST() const { return m_hImageList; } #if !wxUSE_SIMPLER_DRAGIMAGE // Returns the native image list handle for the cursor WXHIMAGELIST GetCursorHIMAGELIST() const { return m_hCursorImageList; } #endif protected: WXHIMAGELIST m_hImageList; #if wxUSE_SIMPLER_DRAGIMAGE wxCursor m_oldCursor; #else WXHIMAGELIST m_hCursorImageList; #endif wxCursor m_cursor; // wxPoint m_cursorHotspot; // Obsolete wxPoint m_position; wxWindow* m_window; wxRect m_boundingRect; bool m_fullScreen; private: DECLARE_DYNAMIC_CLASS(wxDragImage) }; #endif // _WX_DRAGIMAG_H_