The canvas window. More...

#include <wxiviewcanvas.h>

Public Types
enum	{ wxICANVAS_MOUSE_SELECTION = 1, wxICANVAS_MOUSE_SCROLL = 2, wxICANVAS_MOUSEWHEEL_SCROLL = 4 }
	wxIViewCanvas options (use SetOptions() function to set). More...
Public Member Functions
	wxIViewCanvas (wxWindow *poParent, wxWindowID nId=wxID_ANY, const wxPoint &oPos=wxDefaultPosition, const wxSize &oSize=wxDefaultSize, long nStyle=wxHSCROLL\|wxVSCROLL\|wxSUNKEN_BORDER, const wxString &strName=wxT("wxIViewCanvas"))
	Standard constructor.
virtual	~wxIViewCanvas ()
	Virtual destructor.
void	OnPaint (wxPaintEvent &oEvent)
	Handler for window (re)painting.
virtual void	Paint (wxDC &oDc)
	Repaints the image (using an internal bitmap).
virtual wxBitmap &	GetBitmap ()
	Returns the internal bitmap.
virtual void	SetBitmap (const wxBitmap &oBitmap)
	Sets the internal bitmap.
void	OnSize (wxSizeEvent &oEvent)
	Handle resizing.
void	OnTimer (wxTimerEvent &oEvent)
	Handle timer events.
void	OnMouse_ (wxMouseEvent &oEvent)
	Handle mouse events (non virtual part, only calls the virtual part, see OnMouse() instead).
virtual void	OnMouse (wxMouseEvent &oEvent)
	Handle mouse events (the virtual, customizable part).
virtual void	SetOptions (int nOptions)
	Set options for the wxIViewCanvas.
virtual void	ClearSelection ()
	Clears up (deletes) the current selection.
virtual wxRect &	GetSelection ()
	Gets the selection rectangle.
virtual bool	IsSelected ()
	Checks if a selection area exists.
Protected Attributes
int	m_nOptions
	Holds extended style info (options).
wxBitmap	m_oBitmap
	Internal bitmap object for repainting.
wxTimer	m_oTimer
	Timer for delay before sending resizing event to parent window.
wxPoint	m_oMousePosBegin
	Save the starting point of a mouse movement.
wxPoint	m_oMousePosOld
	Save former mouse position.
wxRect	m_oSelection
	Holds the selection.

Detailed Description

The canvas window.

...

Definition at line 109 of file wxiviewcanvas.h.

Member Enumeration Documentation

anonymous enum

wxIViewCanvas options (use SetOptions() function to set).

Enumerator:

wxICANVAS_MOUSE_SELECTION	Enable selecting a rectangular image region. (Default is OFF.)
wxICANVAS_MOUSE_SCROLL	Enable scrolling following mouse cursor on right mouse key pressed. (Default is ON.)
wxICANVAS_MOUSEWHEEL_SCROLL	Enable selecting a rectangular image region. (Default is ON)

Definition at line 199 of file wxiviewcanvas.h.

    {
        wxICANVAS_MOUSE_SELECTION= 1,   ///< Enable selecting a rectangular image region. (Default is OFF.)
        wxICANVAS_MOUSE_SCROLL=  2,     ///< Enable scrolling following mouse cursor on right mouse key pressed. (Default is ON.)
        wxICANVAS_MOUSEWHEEL_SCROLL= 4  ///< Enable selecting a rectangular image region. (Default is ON)
    };

Constructor & Destructor Documentation

wxIViewCanvas::wxIViewCanvas	(	wxWindow *	poParent,
		wxWindowID	nId = `wxID_ANY`,
		const wxPoint &	oPos = `wxDefaultPosition`,
		const wxSize &	oSize = `wxDefaultSize`,
		long	nStyle = `wxHSCROLL \| wxVSCROLL \| wxSUNKEN_BORDER`,
		const wxString &	strName = `wxT( "wxIViewCanvas" )`
	)

Standard constructor.

Parameters:

poParent	a pointer to the dialog windows's parent window.
nId	the window id, default: 1
oPos	the window position, default: wxDefaultPosition
oSize	the window size, default: wxDefaultSize
nStyle	window style (default: wxHSCROLL \| wxVSCROLL \| wxSUNKEN_BORDER)
strName	class name (default: wxT( "wxIViewCanvas" ))

Definition at line 47 of file wxiviewcanvas.cpp.

  : wxScrolledWindow( poParent, nId, oPos, oSize, nStyle, strName ),
    m_nOptions( wxICANVAS_MOUSE_SCROLL | wxICANVAS_MOUSEWHEEL_SCROLL )
{
    // Initialization.
    m_oTimer.SetOwner( this );

    // Reset selection.
    ClearSelection();
}

virtual wxIViewCanvas::~wxIViewCanvas ( ) [inline, virtual]

Virtual destructor.

Definition at line 129 of file wxiviewcanvas.h.

{}

Member Function Documentation

virtual void wxIViewCanvas::ClearSelection ( ) [inline, virtual]

Clears up (deletes) the current selection.

Definition at line 178 of file wxiviewcanvas.h.

References m_oSelection.

Referenced by OnMouse(), and SetBitmap().

    {
//        RefreshRect( m_oSelection );
        Refresh();
        m_oSelection= wxRect( -1, -1, 0, 0 );
    }

virtual wxBitmap& wxIViewCanvas::GetBitmap ( ) [inline, virtual]

Returns the internal bitmap.

Definition at line 142 of file wxiviewcanvas.h.

References m_oBitmap.

{ return m_oBitmap; }

virtual wxRect& wxIViewCanvas::GetSelection ( ) [inline, virtual]

Gets the selection rectangle.

Definition at line 186 of file wxiviewcanvas.h.

References m_oSelection.

Referenced by wxIScanFrame::GetImageSelection(), and wxIScanFrame::OnDocumentZoom().

{ return m_oSelection; };

virtual bool wxIViewCanvas::IsSelected ( ) [inline, virtual]

Checks if a selection area exists.

Definition at line 189 of file wxiviewcanvas.h.

References m_oSelection.

Referenced by wxIScanFrame::GetImageSelection(), wxIScanFrame::OnDocumentZoom(), and Paint().

    {
        return    ( m_oSelection.x >= 0 )
               && ( m_oSelection.y >= 0 )
               && ( m_oSelection.width > 1 )
               && ( m_oSelection.height > 1 );
    }

void wxIViewCanvas::OnMouse ( wxMouseEvent & oEvent ) [virtual]

Handle mouse events (the virtual, customizable part).

Parameters:

oEvent Contains the mouse event to handle.

OnMouse() handles the following events depending on the options set by a previous call to SetOptions():

Scrolling while moving the mouse keeping the right mouse button pressed (wxICANVAS_MOUSE_SCROLL).
Scrolling vertically using the mouse wheel. (wxICANVAS_MOUSEWHEEL_SCROLL)
Setting a selection rectangle by using a rubber band while keeping the left mouse button pressed. (wxICANVAS_MOUSE_SELECTION)

Definition at line 110 of file wxiviewcanvas.cpp.

References ClearSelection(), wxIViewCanvasSelectedEvent::m_bAlt, wxIViewCanvasSelectedEvent::m_bCtrl, wxIViewCanvasSelectedEvent::m_bMeta, wxIViewCanvasSelectedEvent::m_bShift, m_nOptions, m_oMousePosBegin, m_oMousePosOld, wxIViewCanvasSelectedEvent::m_oSelection, m_oSelection, wxICANVAS_MOUSE_SCROLL, wxICANVAS_MOUSE_SELECTION, and wxICANVAS_MOUSEWHEEL_SCROLL.

Referenced by OnMouse_().

{
    if( m_nOptions & wxICANVAS_MOUSE_SCROLL )
    {
        // Process right mouse button events.
        if( oEvent.RightDown() )
        {
            // Change mouse cursor.
            SetCursor( wxCursor( wxCURSOR_HAND ) );

            // Remember former mouse position.
            m_oMousePosOld= wxPoint( oEvent.GetX(), oEvent.GetY() );
        }
        else if ( oEvent.RightUp() )
        {
            // Reset mouse cursor.
            SetCursor( wxNullCursor );
        }
        else if ( oEvent.Dragging() && oEvent.RightIsDown() )
        {
            // Get mouse position.
            wxPoint oMousePos( oEvent.GetX(), oEvent.GetY() );

            // Get the virtual position of upper left corner
            // (the view start).
            wxPoint nViewStart;

            GetViewStart( &nViewStart.x, &nViewStart.y );

            // Calculate scrolling parameters and scroll image.
            //
            // NOTE: This only works because scroll unit size ist set to
            //       1 pixel per horizontal/vertikal scroll unit in
            //       void wxIViewCanvas::SetBitmap( const wxBitmap &oBitmap ).
            //
            Scroll( nViewStart.x - ( oMousePos.x - m_oMousePosOld.x ),
                    nViewStart.y - ( oMousePos.y - m_oMousePosOld.y ) );

            // Save the mouse position for further use.
            m_oMousePosOld= oMousePos;
        }
    }
    if( m_nOptions & wxICANVAS_MOUSEWHEEL_SCROLL )
    {
        if( oEvent.GetWheelRotation() != 0 )
        {
            // Get the virtual position of upper left corner
            // (the view start).
            wxPoint nViewStart;

            GetViewStart( &nViewStart.x, &nViewStart.y );

            // Calculate scrolling parameters and scroll image.
            //
            // NOTE: This only works because scroll unit size ist set to
            //       1 pixel per horizontal/vertikal scroll unit in
            //       void wxIViewCanvas::SetBitmap( const wxBitmap &oBitmap ).
            //
            Scroll( nViewStart.x,
                    nViewStart.y - oEvent.GetWheelRotation() / 5 );
        }
    }
    if( m_nOptions & wxICANVAS_MOUSE_SELECTION )
    {
        // Process left mouse button events
        if( oEvent.LeftDown() )
        {
            // Clear a posible selection.
            ClearSelection();

            // Change mouse cursor.
            SetCursor( wxCursor( wxCURSOR_CROSS ) );

            // Remember former mouse position.
            m_oMousePosOld= wxPoint( oEvent.GetX(), oEvent.GetY() );

            // Save starting point of the mouse movement.
            m_oMousePosBegin= m_oMousePosOld;
        }
        else if ( oEvent.LeftUp() )
        {
            // Reset mouse cursor.
            SetCursor( wxNullCursor );

            // Get mouse position.
            wxPoint oMousePos( oEvent.GetX(), oEvent.GetY() );

            // Get the virtual position of upper left corner
            // (the view start).
            wxPoint nViewStart;

            GetViewStart( &nViewStart.x, &nViewStart.y );

            // Remember selection.
            m_oSelection= wxRect( nViewStart.x + m_oMousePosBegin.x, nViewStart.y + m_oMousePosBegin.y,
                                  oMousePos.x - m_oMousePosBegin.x + 1, oMousePos.y - m_oMousePosBegin.y + 1 );

            // Do some coordinate corrections.
            if( m_oSelection.width < 0 )
            {
                m_oSelection.x += m_oSelection.width;
                m_oSelection.width= -m_oSelection.width;
            }
            if( m_oSelection.height < 0 )
            {
                m_oSelection.y += m_oSelection.height;
                m_oSelection.height= -m_oSelection.height;
            }
            if( m_oSelection.x < 0 )
            {
                m_oSelection.width += m_oSelection.x;
                m_oSelection.x= 0;
            }
            if( m_oSelection.y < 0 )
            {
                m_oSelection.height += m_oSelection.y;
                m_oSelection.y= 0;
            }

            // Notify the next window in the parent chain that there
            // is a new selection.
            //
            // Note: An event of type wxIViewCanvasSelectedEvent is
            //       propageted to the parent window chain by default.
            wxIViewCanvasSelectedEvent oIViewCanvasSelectedEvent;

            oIViewCanvasSelectedEvent.m_bShift= oEvent.ShiftDown();
            oIViewCanvasSelectedEvent.m_bAlt  = oEvent.AltDown();
            oIViewCanvasSelectedEvent.m_bCtrl = oEvent.ControlDown();
            oIViewCanvasSelectedEvent.m_bMeta = oEvent.MetaDown();
            oIViewCanvasSelectedEvent.m_oSelection= m_oSelection;

            ProcessEvent( oIViewCanvasSelectedEvent );
        }
        else if ( oEvent.Dragging() && oEvent.LeftIsDown() )
        {
            // Get mouse position.
            wxPoint oMousePos( oEvent.GetX(), oEvent.GetY() );

            // ..
            wxClientDC oDc( this );

            oDc.SetPen( *wxBLACK_DASHED_PEN );
            oDc.SetBrush( *wxTRANSPARENT_BRUSH );
            oDc.SetLogicalFunction( wxINVERT );
            oDc.DrawRectangle( m_oMousePosBegin.x, m_oMousePosBegin.y,
                               m_oMousePosOld.x - m_oMousePosBegin.x + 1, m_oMousePosOld.y - m_oMousePosBegin.y + 1 );
            oDc.DrawRectangle( m_oMousePosBegin.x, m_oMousePosBegin.y,
                               oMousePos.x - m_oMousePosBegin.x + 1, oMousePos.y - m_oMousePosBegin.y + 1 );

            // Save the mouse position for further use.
            m_oMousePosOld= oMousePos;
        }
    }
}

void wxIViewCanvas::OnMouse_ ( wxMouseEvent & oEvent ) [inline]

Handle mouse events (non virtual part, only calls the virtual part, see OnMouse() instead).

Parameters:

oEvent Contains the mouse event to handle.

Definition at line 157 of file wxiviewcanvas.h.

References OnMouse().

{ OnMouse( oEvent ); }

void wxIViewCanvas::OnPaint ( wxPaintEvent & oEvent )

Handler for window (re)painting.

Creates and prepares a device context and calls Paint( wxDC& oDc ).

Definition at line 64 of file wxiviewcanvas.cpp.

References Paint().

{
    // Create a device context...
    //
    wxPaintDC oDc( this );

    // ... and prepare it even if there is not a bitmap to paint
    // for to repaint at least the window background etc.
    //
    PrepareDC( oDc );

    // Paint (the bitmap).
    Paint( oDc );
}

void wxIViewCanvas::OnSize ( wxSizeEvent & oEvent )

Handle resizing.

Definition at line 81 of file wxiviewcanvas.cpp.

References m_oTimer, and WXIVIEWCANVASDELAY.

{
    // Check if the timer is running, and...
    if( m_oTimer.IsRunning() )
    {
        // ... stop it.
        m_oTimer.Stop();
    }

    // Create a one shot timer event in 50ms.
    m_oTimer.Start( WXIVIEWCANVASDELAY, wxTIMER_ONE_SHOT );
}

void wxIViewCanvas::OnTimer ( wxTimerEvent & oEvent )

Handle timer events.

Definition at line 96 of file wxiviewcanvas.cpp.

{
    // Notify the next window in the parent chain that the canvas size
    // has changed.
    //
    // Note: An event of type wxIViewCanvasSizeEvent is propageted
    //       to the parent window chain by default.
    wxIViewCanvasSizeEvent oEvent;

    ProcessEvent( oEvent );
}

void wxIViewCanvas::Paint ( wxDC & oDc ) [virtual]

Repaints the image (using an internal bitmap).

Definition at line 268 of file wxiviewcanvas.cpp.

References IsSelected(), m_oBitmap, and m_oSelection.

Referenced by OnPaint().

{
#if wxCHECK_VERSION( 2, 9, 0 )
    if( oDc.IsOk() )
#else
    if( oDc.Ok() )
#endif // wxCHECK_VERSION( 2, 9, 0 )
    {
        // If there is a bitmap connected to this canvas window (re)paint it.
        if( m_oBitmap.Ok() )
        {
            // Repaint the bitmap.
            oDc.DrawBitmap( m_oBitmap, 0, 0 );

        }

        // If there is a selection repaint the surrounding rectangle.
        if( IsSelected() )
        {
            oDc.SetPen( *wxBLACK_DASHED_PEN );
            oDc.SetBrush( *wxTRANSPARENT_BRUSH );
            oDc.SetLogicalFunction( wxINVERT );
            oDc.DrawRectangle( m_oSelection.x, m_oSelection.y, m_oSelection.width, m_oSelection.height );
        }
    }
}

void wxIViewCanvas::SetBitmap ( const wxBitmap & oBitmap ) [virtual]

Sets the internal bitmap.

Definition at line 297 of file wxiviewcanvas.cpp.

References ClearSelection(), and m_oBitmap.

Referenced by wxIScanFrame::UpdateBitmap().

{
    // Save the (new) bitmap,...
    m_oBitmap= oBitmap;

    // ... adjust the scrollbars, ...
    SetScrollbars( 1, 1, m_oBitmap.GetWidth(), m_oBitmap.GetHeight() );

    // ... clear a posible selection, ...
    ClearSelection();

    // .. and refresh (repaint) the windown content.
    Refresh();
}