dnd.cpp

wxWidgets 是一个跨平台的 GUI 框架。它给开发人员提供了统一的接口

            if ( dataSize > 0 )
                dataSize--;
            dataPtr[ dataSize ] = 0;
            if ( type == 'utxt' )
            {
                if ( dataSize > 0 )
                    dataSize--;
                dataPtr[ dataSize ] = 0;
            }

            AddDragItemFlavor( theDrag, theItem, type, dataPtr, dataSize, 0 );
        }
        else if (type == kDragFlavorTypeHFS )
        {
            HFSFlavor  theFlavor;
            OSErr err = noErr;
#ifndef __LP64__
            CInfoPBRec cat;

            wxMacFilename2FSSpec( wxString( dataPtr, *wxConvCurrent ), &theFlavor.fileSpec );

            memset( &cat, 0, sizeof(cat) );
            cat.hFileInfo.ioNamePtr = theFlavor.fileSpec.name;
            cat.hFileInfo.ioVRefNum = theFlavor.fileSpec.vRefNum;
            cat.hFileInfo.ioDirID = theFlavor.fileSpec.parID;
            cat.hFileInfo.ioFDirIndex = 0;
            err = PBGetCatInfoSync( &cat );
#endif
          if (err == noErr)
            {
#ifndef __LP64__
                theFlavor.fdFlags = cat.hFileInfo.ioFlFndrInfo.fdFlags;
                if (theFlavor.fileSpec.parID == fsRtParID)
                {
                    theFlavor.fileCreator = 'MACS';
                    theFlavor.fileType = 'disk';
                }
                else if ((cat.hFileInfo.ioFlAttrib & ioDirMask) != 0)
                {
                    theFlavor.fileCreator = 'MACS';
                    theFlavor.fileType = 'fold';
                }
                else
                {
                    theFlavor.fileCreator = cat.hFileInfo.ioFlFndrInfo.fdCreator;
                    theFlavor.fileType = cat.hFileInfo.ioFlFndrInfo.fdType;
                }
#endif
                AddDragItemFlavor( theDrag, theItem, type, &theFlavor, sizeof(theFlavor), 0 );
            }
        }
        else
        {
            AddDragItemFlavor( theDrag, theItem, type, dataPtr, dataSize, 0 );
        }

        delete [] dataPtr;
    }

    delete [] formats;

    dragRegion = NewRgn();
    RgnHandle tempRgn = NewRgn();

    EventRecord* ev = NULL;

#if !TARGET_CARBON // TODO
    ev = (EventRecord*) wxTheApp->MacGetCurrentEvent();
#else
    EventRecord rec;
    ev = &rec;
    wxMacConvertEventToRecord( (EventRef) wxTheApp->MacGetCurrentEvent(), &rec );
#endif

    const short dragRegionOuterBoundary = 10;
    const short dragRegionInnerBoundary = 9;

    SetRectRgn(
        dragRegion,
        ev->where.h - dragRegionOuterBoundary,
        ev->where.v  - dragRegionOuterBoundary,
        ev->where.h + dragRegionOuterBoundary,
        ev->where.v + dragRegionOuterBoundary );

    SetRectRgn(
        tempRgn,
        ev->where.h - dragRegionInnerBoundary,
        ev->where.v - dragRegionInnerBoundary,
        ev->where.h + dragRegionInnerBoundary,
        ev->where.v + dragRegionInnerBoundary );

    DiffRgn( dragRegion, tempRgn, dragRegion );
    DisposeRgn( tempRgn );

    // TODO: work with promises in order to return data
    // only when drag was successfully completed

    gTrackingGlobals.m_currentSource = this;
    TrackDrag( theDrag, ev, dragRegion );
    DisposeRgn( dragRegion );
    DisposeDrag( theDrag );
    gTrackingGlobals.m_currentSource = NULL;

    bool optionDown = GetCurrentKeyModifiers() & optionKey;
    wxDragResult dndresult = wxDragCopy;
    if ( flags != wxDrag_CopyOnly )
        // on mac the option key is always the indication for copy
        dndresult = optionDown ? wxDragCopy : wxDragMove;

    return dndresult;
}

bool wxDropSource::MacInstallDefaultCursor(wxDragResult effect)
{
    const wxCursor& cursor = GetCursor(effect);
    bool result = cursor.Ok();

    if ( result )
        cursor.MacInstall();

    return result;
}

bool gTrackingGlobalsInstalled = false;

// passing the globals via refcon is not needed by the CFM and later architectures anymore
// but I'll leave it in there, just in case...

pascal OSErr wxMacWindowDragTrackingHandler(
    DragTrackingMessage theMessage, WindowPtr theWindow,
    void *handlerRefCon, DragReference theDrag );
pascal OSErr wxMacWindowDragReceiveHandler(
    WindowPtr theWindow, void *handlerRefCon,
    DragReference theDrag );

void wxMacEnsureTrackingHandlersInstalled()
{
    if ( !gTrackingGlobalsInstalled )
    {
        OSStatus err;

        err = InstallTrackingHandler( NewDragTrackingHandlerUPP(wxMacWindowDragTrackingHandler), 0L, &gTrackingGlobals );
        verify_noerr( err );

        err = InstallReceiveHandler( NewDragReceiveHandlerUPP(wxMacWindowDragReceiveHandler), 0L, &gTrackingGlobals );
        verify_noerr( err );

        gTrackingGlobalsInstalled = true;
    }
}

pascal OSErr wxMacWindowDragTrackingHandler(
    DragTrackingMessage theMessage, WindowPtr theWindow,
    void *handlerRefCon, DragReference theDrag )
{
    MacTrackingGlobals* trackingGlobals = (MacTrackingGlobals*) handlerRefCon;

    Point mouse, localMouse;
    DragAttributes attributes;

    GetDragAttributes( theDrag, &attributes );

    wxTopLevelWindowMac* toplevel = wxFindWinFromMacWindow( theWindow );

    bool optionDown = GetCurrentKeyModifiers() & optionKey;
    wxDragResult result = optionDown ? wxDragCopy : wxDragMove;

    switch (theMessage)
    {
        case kDragTrackingEnterHandler:
        case kDragTrackingLeaveHandler:
            break;

        case kDragTrackingEnterWindow:
            if (trackingGlobals != NULL)
            {
                trackingGlobals->m_currentTargetWindow = NULL;
                trackingGlobals->m_currentTarget = NULL;
            }
            break;

        case kDragTrackingInWindow:
            if (trackingGlobals == NULL)
                break;
            if (toplevel == NULL)
                break;

            GetDragMouse( theDrag, &mouse, 0L );
            localMouse = mouse;
            wxMacGlobalToLocal( theWindow, &localMouse );

            {
                wxWindow *win = NULL;
                ControlPartCode controlPart;
                ControlRef control = wxMacFindControlUnderMouse(
                    toplevel, localMouse, theWindow, &controlPart );
                if ( control )
                    win = wxFindControlFromMacControl( control );
                else
                    win = toplevel;

                int localx, localy;
                localx = localMouse.h;
                localy = localMouse.v;

                if ( win )
                    win->MacRootWindowToWindow( &localx, &localy );
                if ( win != trackingGlobals->m_currentTargetWindow )
                {
                    if ( trackingGlobals->m_currentTargetWindow )
                    {
                        // this window is left
                        if ( trackingGlobals->m_currentTarget )
                        {
#ifndef __LP64__
                            HideDragHilite( theDrag );
#endif
                            trackingGlobals->m_currentTarget->SetCurrentDrag( theDrag );
                            trackingGlobals->m_currentTarget->OnLeave();
                            trackingGlobals->m_currentTarget = NULL;
                            trackingGlobals->m_currentTargetWindow = NULL;
                        }
                    }

                    if ( win )
                    {
                        // this window is entered
                        trackingGlobals->m_currentTargetWindow = win;
                        trackingGlobals->m_currentTarget = win->GetDropTarget();
                        {
                            if ( trackingGlobals->m_currentTarget )
                            {
                                trackingGlobals->m_currentTarget->SetCurrentDrag( theDrag );
                                result = trackingGlobals->m_currentTarget->OnEnter( localx, localy, result );
                            }

                            if ( result != wxDragNone )
                            {
                                int x, y;

                                x = y = 0;
                                win->MacWindowToRootWindow( &x, &y );
                                RgnHandle hiliteRgn = NewRgn();
                                Rect r = { y, x, y + win->GetSize().y, x + win->GetSize().x };
                                RectRgn( hiliteRgn, &r );
#ifndef __LP64__
                                ShowDragHilite( theDrag, hiliteRgn, true );
#endif
                                DisposeRgn( hiliteRgn );
                            }
                        }
                    }
                }
                else
                {
                    if ( trackingGlobals->m_currentTarget )
                    {
                        trackingGlobals->m_currentTarget->SetCurrentDrag( theDrag );
                        trackingGlobals->m_currentTarget->OnDragOver( localx, localy, result );
                    }
                }

                // set cursor for OnEnter and OnDragOver
                if ( trackingGlobals->m_currentSource && !trackingGlobals->m_currentSource->GiveFeedback( result ) )
                {
                  if ( !trackingGlobals->m_currentSource->MacInstallDefaultCursor( result ) )
                  {
                      int cursorID = wxCURSOR_NONE;

                      switch (result)
                      {
                          case wxDragCopy:
                              cursorID = wxCURSOR_COPY_ARROW;
                              break;

                          case wxDragMove:
                              cursorID = wxCURSOR_ARROW;
                              break;

                          case wxDragNone:
                              cursorID = wxCURSOR_NO_ENTRY;
                              break;

                          case wxDragError:
                          case wxDragLink:
                          case wxDragCancel:
                          default:
                              // put these here to make gcc happy
                              ;
                      }

                      if (cursorID != wxCURSOR_NONE)
                      {
                          wxCursor cursor( cursorID );
                          cursor.MacInstall();
                      }
                   }
                }
            }
            break;

        case kDragTrackingLeaveWindow:
            if (trackingGlobals == NULL)
                break;

            if (trackingGlobals->m_currentTarget)
            {
                trackingGlobals->m_currentTarget->SetCurrentDrag( theDrag );
                trackingGlobals->m_currentTarget->OnLeave();
#ifndef __LP64__
                HideDragHilite( theDrag );
#endif
                trackingGlobals->m_currentTarget = NULL;
            }
            trackingGlobals->m_currentTargetWindow = NULL;
            break;

        default:
            break;
    }

    return noErr;
}

pascal OSErr wxMacWindowDragReceiveHandler(
    WindowPtr theWindow,
    void *handlerRefCon,
    DragReference theDrag)
{
    MacTrackingGlobals* trackingGlobals = (MacTrackingGlobals*)handlerRefCon;
    if ( trackingGlobals->m_currentTarget )
    {
        Point mouse, localMouse;
        int localx, localy;

        trackingGlobals->m_currentTarget->SetCurrentDrag( theDrag );
        GetDragMouse( theDrag, &mouse, 0L );
        localMouse = mouse;
        wxMacGlobalToLocal( theWindow, &localMouse );
        localx = localMouse.h;
        localy = localMouse.v;

        // TODO : should we use client coordinates?
        if ( trackingGlobals->m_currentTargetWindow )
            trackingGlobals->m_currentTargetWindow->MacRootWindowToWindow( &localx, &localy );
        if ( trackingGlobals->m_currentTarget->OnDrop( localx, localy ) )
        {
            bool optionDown = GetCurrentKeyModifiers() & optionKey;
            wxDragResult result = optionDown ? wxDragCopy : wxDragMove;
            trackingGlobals->m_currentTarget->OnData( localx, localy, result );
        }
    }

    return noErr;
}

#endif