remove unused variable assignment, closes #14928

[wxWidgets.git] / include / wx / dnd.h

diff --git a/include/wx/dnd.h b/include/wx/dnd.h
index c201cf999261d05f96e0c9bd412ac64c5e9fbe6c..ac3c9c4f8439188fe668e3ceeea491552e1d1a97 100644 (file)
--- a/include/wx/dnd.h
+++ b/include/wx/dnd.h
@@ -5,8 +5,8 @@
 // Modified by:
 // Created:     26.05.99
 // RCS-ID:      $Id$
 // Modified by:
 // Created:     26.05.99
 // RCS-ID:      $Id$

-// Copyright:   (c) wxWindows Team
-// Licence:     wxWindows license
+// Copyright:   (c) wxWidgets Team
+// Licence:     wxWindows licence

 ///////////////////////////////////////////////////////////////////////////////
 
 #ifndef _WX_DND_H_BASE_
 ///////////////////////////////////////////////////////////////////////////////
 
 #ifndef _WX_DND_H_BASE_


@@ -17,11 +17,23 @@
 #if wxUSE_DRAG_AND_DROP
 
 #include "wx/dataobj.h"
 #if wxUSE_DRAG_AND_DROP
 
 #include "wx/dataobj.h"

+#include "wx/cursor.h"

 
 // ----------------------------------------------------------------------------
 // constants
 // ----------------------------------------------------------------------------
 
 
 // ----------------------------------------------------------------------------
 // constants
 // ----------------------------------------------------------------------------
 

+// flags for wxDropSource::DoDragDrop()
+//
+// NB: wxDrag_CopyOnly must be 0 (== FALSE) and wxDrag_AllowMove must be 1
+//     (== TRUE) for compatibility with the old DoDragDrop(bool) method!
+enum
+{
+    wxDrag_CopyOnly    = 0, // allow only copying
+    wxDrag_AllowMove   = 1, // allow moving (copying is always allowed)
+    wxDrag_DefaultMove = 3  // the default operation is move, not copy
+};
+

 // result of wxDropSource::DoDragDrop() call
 enum wxDragResult
 {
 // result of wxDropSource::DoDragDrop() call
 enum wxDragResult
 {


@@ -29,53 +41,102 @@ enum wxDragResult
     wxDragNone,     // drag target didn't accept the data
     wxDragCopy,     // the data was successfully copied
     wxDragMove,     // the data was successfully moved (MSW only)
     wxDragNone,     // drag target didn't accept the data
     wxDragCopy,     // the data was successfully copied
     wxDragMove,     // the data was successfully moved (MSW only)

+    wxDragLink,     // operation is a drag-link

     wxDragCancel    // the operation was cancelled by user (not an error)
 };
 
     wxDragCancel    // the operation was cancelled by user (not an error)
 };
 

+// return true if res indicates that something was done during a dnd operation,
+// i.e. is neither error nor none nor cancel
+WXDLLIMPEXP_CORE bool wxIsDragResultOk(wxDragResult res);
+

 // ----------------------------------------------------------------------------
 // wxDropSource is the object you need to create (and call DoDragDrop on it)
 // to initiate a drag-and-drop operation
 // ----------------------------------------------------------------------------
 
 // ----------------------------------------------------------------------------
 // wxDropSource is the object you need to create (and call DoDragDrop on it)
 // to initiate a drag-and-drop operation
 // ----------------------------------------------------------------------------
 

-class WXDLLEXPORT wxDropSourceBase
+class WXDLLIMPEXP_CORE wxDropSourceBase

 {
 public:
 {
 public:

-    wxDropSourceBase() { m_data = (wxDataObject *)NULL; }
+    wxDropSourceBase(const wxCursor &cursorCopy = wxNullCursor,
+                     const wxCursor &cursorMove = wxNullCursor,
+                     const wxCursor &cursorStop = wxNullCursor)
+        : m_cursorCopy(cursorCopy),
+          m_cursorMove(cursorMove),
+          m_cursorStop(cursorStop)
+        { m_data = NULL; }

     virtual ~wxDropSourceBase() { }
 
     // set the data which is transfered by drag and drop
     virtual ~wxDropSourceBase() { }
 
     // set the data which is transfered by drag and drop

-    void SetData(wxDataObject& data) { delete m_data; m_data = &data; }
+    void SetData(wxDataObject& data)
+      { m_data = &data; }
+
+    wxDataObject *GetDataObject()
+      { return m_data; }
+
+    // set the icon corresponding to given drag result
+    void SetCursor(wxDragResult res, const wxCursor& cursor)
+    {
+        if ( res == wxDragCopy )
+            m_cursorCopy = cursor;
+        else if ( res == wxDragMove )
+            m_cursorMove = cursor;
+        else
+            m_cursorStop = cursor;
+    }

 
     // start drag action, see enum wxDragResult for return value description
     //
 
     // start drag action, see enum wxDragResult for return value description
     //

-    // if bAllowMove is TRUE, data can be moved, if not - only copied
-    virtual wxDragResult DoDragDrop( bool bAllowMove = FALSE );
+    // if flags contains wxDrag_AllowMove, moving (and only copying) data is
+    // allowed, if it contains wxDrag_DefaultMove (which includes the previous
+    // flag), it is even the default operation
+    virtual wxDragResult DoDragDrop(int flags = wxDrag_CopyOnly) = 0;

 
     // override to give feedback depending on the current operation result
 
     // override to give feedback depending on the current operation result

-    // "effect"
-    virtual bool GiveFeedback( wxDragResult WXUNUSED(effect),
-                               bool WXUNUSED(bScrolling) )
+    // "effect" and return true if you did something, false to let the library
+    // give the default feedback
+    virtual bool GiveFeedback(wxDragResult WXUNUSED(effect)) { return false; }
+
+protected:
+    const wxCursor& GetCursor(wxDragResult res) const

     {
     {

-        return TRUE;
+        if ( res == wxDragCopy )
+            return m_cursorCopy;
+        else if ( res == wxDragMove )
+            return m_cursorMove;
+        else
+            return m_cursorStop;

     }
 
     }
 

-protected:
+    // the data we're dragging

     wxDataObject *m_data;
     wxDataObject *m_data;

+
+    // the cursors to use for feedback
+    wxCursor m_cursorCopy,
+             m_cursorMove,
+             m_cursorStop;
+
+    wxDECLARE_NO_COPY_CLASS(wxDropSourceBase);

 };
 
 // ----------------------------------------------------------------------------
 // wxDropTarget should be associated with a window if it wants to be able to
 };
 
 // ----------------------------------------------------------------------------
 // wxDropTarget should be associated with a window if it wants to be able to

-// receive data via drag and drop
+// receive data via drag and drop.
+//
+// To use this class, you should derive from wxDropTarget and implement
+// OnData() pure virtual method. You may also wish to override OnDrop() if you
+// want to accept the data only inside some region of the window (this may
+// avoid having to copy the data to this application which happens only when
+// OnData() is called)

 // ----------------------------------------------------------------------------
 
 // ----------------------------------------------------------------------------
 

-class WXDLLEXPORT wxDropTargetBase
+class WXDLLIMPEXP_CORE wxDropTargetBase

 {
 public:
     // ctor takes a pointer to heap-allocated wxDataObject which will be owned
     // by wxDropTarget and deleted by it automatically. If you don't give it
     // here, you can use SetDataObject() later.
     wxDropTargetBase(wxDataObject *dataObject = NULL)
 {
 public:
     // ctor takes a pointer to heap-allocated wxDataObject which will be owned
     // by wxDropTarget and deleted by it automatically. If you don't give it
     // here, you can use SetDataObject() later.
     wxDropTargetBase(wxDataObject *dataObject = NULL)

-        { m_dataObject = dataObject; }
+        { m_dataObject = dataObject; m_defaultAction = wxDragNone; }

     // dtor deletes our data object
     virtual ~wxDropTargetBase()
         { delete m_dataObject; }
     // dtor deletes our data object
     virtual ~wxDropTargetBase()
         { delete m_dataObject; }


@@ -84,29 +145,65 @@ public:
     wxDataObject *GetDataObject() const
         { return m_dataObject; }
     void SetDataObject(wxDataObject *dataObject)
     wxDataObject *GetDataObject() const
         { return m_dataObject; }
     void SetDataObject(wxDataObject *dataObject)

-        { delete m_dataObject; m_dataObject = dataObject; }
+        { if (m_dataObject) delete m_dataObject;
+    m_dataObject = dataObject; }
+
+    // these functions are called when data is moved over position (x, y) and
+    // may return either wxDragCopy, wxDragMove or wxDragNone depending on
+    // what would happen if the data were dropped here.
+    //
+    // the last parameter is what would happen by default and is determined by
+    // the platform-specific logic (for example, under Windows it's wxDragCopy
+    // if Ctrl key is pressed and wxDragMove otherwise) except that it will
+    // always be wxDragNone if the carried data is in an unsupported format.

 
 

-    // called when mouse enters/leaves the window: might be used to give
-    // some visual feedback to the user
-    virtual void OnEnter() { }
+    // called when the mouse enters the window (only once until OnLeave())
+    virtual wxDragResult OnEnter(wxCoord x, wxCoord y, wxDragResult def)
+        { return OnDragOver(x, y, def); }
+
+    // called when the mouse moves in the window - shouldn't take long to
+    // execute or otherwise mouse movement would be too slow
+    virtual wxDragResult OnDragOver(wxCoord WXUNUSED(x), wxCoord WXUNUSED(y),
+                                    wxDragResult def)
+        { return def; }
+
+    // called when mouse leaves the window: might be used to remove the
+    // feedback which was given in OnEnter()

     virtual void OnLeave() { }
 
     // this function is called when data is dropped at position (x, y) - if it
     virtual void OnLeave() { }
 
     // this function is called when data is dropped at position (x, y) - if it

-    // returns TRUE, OnData() will be called immediately afterwards which will
+    // returns true, OnData() will be called immediately afterwards which will

     // allow to retrieve the data dropped.
     virtual bool OnDrop(wxCoord x, wxCoord y) = 0;
 
     // called after OnDrop() returns TRUE: you will usually just call
     // GetData() from here and, probably, also refresh something to update the
     // allow to retrieve the data dropped.
     virtual bool OnDrop(wxCoord x, wxCoord y) = 0;
 
     // called after OnDrop() returns TRUE: you will usually just call
     // GetData() from here and, probably, also refresh something to update the

-    // new data
-    virtual bool OnData() = 0;
+    // new data and, finally, return the code indicating how did the operation
+    // complete (returning default value in case of success and wxDragError on
+    // failure is usually ok)
+    virtual wxDragResult OnData(wxCoord x, wxCoord y, wxDragResult def) = 0;

 
     // may be called *only* from inside OnData() and will fill m_dataObject
 
     // may be called *only* from inside OnData() and will fill m_dataObject

-    // with the data from the drop source if it returns TRUE
+    // with the data from the drop source if it returns true

     virtual bool GetData() = 0;
 
     virtual bool GetData() = 0;
 

+    // sets the default action for drag and drop:
+    // use wxDragMove or wxDragCopy to set deafult action to move or copy
+    // and use wxDragNone (default) to set default action specified by
+    // initialization of draging (see wxDropSourceBase::DoDragDrop())
+    void SetDefaultAction(wxDragResult action)
+        { m_defaultAction = action; }
+
+    // returns default action for drag and drop or
+    // wxDragNone if this not specified
+    wxDragResult GetDefaultAction()
+        { return m_defaultAction; }
+

 protected:
     wxDataObject *m_dataObject;
 protected:
     wxDataObject *m_dataObject;

+    wxDragResult m_defaultAction;
+
+    wxDECLARE_NO_COPY_CLASS(wxDropTargetBase);

 };
 
 // ----------------------------------------------------------------------------
 };
 
 // ----------------------------------------------------------------------------


@@ -114,23 +211,57 @@ protected:
 // ----------------------------------------------------------------------------
 
 #if defined(__WXMSW__)
 // ----------------------------------------------------------------------------
 
 #if defined(__WXMSW__)

-    #include "wx/dataobj.h"

     #include "wx/msw/ole/dropsrc.h"
     #include "wx/msw/ole/droptgt.h"
 #elif defined(__WXMOTIF__)
     #include "wx/motif/dnd.h"
     #include "wx/msw/ole/dropsrc.h"
     #include "wx/msw/ole/droptgt.h"
 #elif defined(__WXMOTIF__)
     #include "wx/motif/dnd.h"

-#elif defined(__WXGTK__)
+#elif defined(__WXX11__)
+    #include "wx/x11/dnd.h"
+#elif defined(__WXGTK20__)

     #include "wx/gtk/dnd.h"
     #include "wx/gtk/dnd.h"

-#elif defined(__WXQT__)
-    #include "wx/qt/dnd.h"
+#elif defined(__WXGTK__)
+    #include "wx/gtk1/dnd.h"

 #elif defined(__WXMAC__)
 #elif defined(__WXMAC__)

-    #include "wx/mac/dnd.h"
+    #include "wx/osx/dnd.h"

 #elif defined(__WXPM__)
     #include "wx/os2/dnd.h"
 #elif defined(__WXPM__)
     #include "wx/os2/dnd.h"

-#elif defined(__WXSTUBS__)
-    #include "wx/stubs/dnd.h"

 #endif
 
 #endif
 

+// ----------------------------------------------------------------------------
+// standard wxDropTarget implementations (implemented in common/dobjcmn.cpp)
+// ----------------------------------------------------------------------------
+
+// A simple wxDropTarget derived class for text data: you only need to
+// override OnDropText() to get something working
+class WXDLLIMPEXP_CORE wxTextDropTarget : public wxDropTarget
+{
+public:
+    wxTextDropTarget();
+
+    virtual bool OnDropText(wxCoord x, wxCoord y, const wxString& text) = 0;
+
+    virtual wxDragResult OnData(wxCoord x, wxCoord y, wxDragResult def);
+
+private:
+    wxDECLARE_NO_COPY_CLASS(wxTextDropTarget);
+};
+
+// A drop target which accepts files (dragged from File Manager or Explorer)
+class WXDLLIMPEXP_CORE wxFileDropTarget : public wxDropTarget
+{
+public:
+    wxFileDropTarget();
+
+    // parameters are the number of files and the array of file names
+    virtual bool OnDropFiles(wxCoord x, wxCoord y,
+                             const wxArrayString& filenames) = 0;
+
+    virtual wxDragResult OnData(wxCoord x, wxCoord y, wxDragResult def);
+
+private:
+    wxDECLARE_NO_COPY_CLASS(wxFileDropTarget);
+};
+

 #endif // wxUSE_DRAG_AND_DROP
 
 #endif // _WX_DND_H_BASE_
 #endif // wxUSE_DRAG_AND_DROP
 
 #endif // _WX_DND_H_BASE_