examples/Graphics/WS/PtBuffer/PointerMoveBuffer.cpp

/*
Copyright (c) 2005-2010 Nokia Corporation and/or its subsidiary(-ies). All rights reserved.

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modification, are permitted provided that the following conditions are met:

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� list of conditions and the following disclaimer.
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� this list of conditions and the following disclaimer in the documentation
� and/or other materials provided with the distribution.
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� may be used to endorse or promote products derived from this software
� without specific prior written permission.

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AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
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OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

Description:�Hold down the SHIFT key and drag the mouse (with left mouse button down)
        for freehand drawing. 
*/

#include <w32std.h>
#include "Base.h"
#include "PointerMoveBuffer.h"



//                                       CMainWindow implementation


/****************************************************************************\
|       Function:       Constructor/Destructor for CMainWindow
|       Input:          aClient         Client application that owns the window
\****************************************************************************/
CMainWindow::CMainWindow (CWsClient* aClient)
: CWindow (aClient)
        {
        }


CMainWindow::~CMainWindow ()
        {
        iWindow.Close();
        }

/****************************************************************************\
|       Function:       CMainWindow::Draw
|       Purpose:        Redraws the contents of CMainWindow within a given
|                               rectangle.
|       Input:          aRect   Rectangle that needs redrawing
|       Output:         None
\****************************************************************************/

void CMainWindow::Draw(const TRect& aRect)
        {
        CWindowGc* gc=SystemGc(); // get a gc
        gc->SetClippingRect(aRect); // clip outside this rect
        gc->Clear(aRect); // clear
}

/****************************************************************************\
|       Function:       CMainWindow::HandlePointerBufferReady
\****************************************************************************/

void CMainWindow::HandlePointerMoveBufferReady ()
        {               
        TPoint pnts[KPointerMoveBufferSize];
        TPtr8 ptr((TUint8 *)&pnts,sizeof(pnts));
        TInt numPnts=Window().RetrievePointerMoveBuffer(ptr);
        TSize size = Window().Size();
        TPoint position = Window().Position();
        TRect redrawRect (position, size);
        CWindowGc* gc=SystemGc();
        gc->Activate(Window());
        Window().Invalidate();
        Window().BeginRedraw(redrawRect); // N.B. Redrawer::RunL() gets called with this 
                                                                          // rectangle - must give it a non-zero value
        for(TInt index=0;index<numPnts;index++) gc->DrawLineTo(pnts[index]);
        Window().EndRedraw();
        gc->Deactivate();
        }

/****************************************************************************\
|       Function:       CMainWindow::HandlePointerEvent
|       Purpose:        Handles pointer events for CMainWindow.
|       Input:          aPointerEvent   The pointer event!
|       Output:         None
\****************************************************************************/

void CMainWindow::HandlePointerEvent (TPointerEvent& aPointerEvent)
        {       
        switch (aPointerEvent.iType)
                {
                case TPointerEvent::EButton1Down:
                        {
                        if (aPointerEvent.iModifiers&EModifierShift)
                                {
                                Window().EnablePointerMoveBuffer();
                                CWindowGc* gc = SystemGc();
                                gc->Activate(Window());
                                gc->MoveTo(aPointerEvent.iPosition);
                                gc->Deactivate();
                                }
                        break;
                        }
                case TPointerEvent::EButton1Up:
                        {
                        Window().DisablePointerMoveBuffer();
                        break;
                        }
                default:
                        break;
                }
}


//                                       CExampleWsClient implementation

CExampleWsClient* CExampleWsClient::NewL(const TRect& aRect)
        {
        // make new client
        CExampleWsClient* client=new (ELeave) CExampleWsClient(aRect); 
        CleanupStack::PushL(client); // push, just in case
        client->ConstructL(); // construct and run
        CleanupStack::Pop();
        return client;
        }

/****************************************************************************\
|       Function:       Constructor/Destructor for CExampleWsClient
|                               Destructor deletes everything that was allocated by
|                               ConstructMainWindowL()
\****************************************************************************/

CExampleWsClient::CExampleWsClient(const TRect& aRect)
:iRect(aRect)
        {
        }

CExampleWsClient::~CExampleWsClient ()
        {
        delete iMainWindow;
        }


/****************************************************************************\
|       Function:       CExampleWsClient::ConstructMainWindowL()
|                               Called by base class's ConstructL
|       Purpose:        Allocates and creates all the windows owned by this client
|                               (See list of windows in CExampleWsCLient declaration).
\****************************************************************************/

void CExampleWsClient::ConstructMainWindowL()
        {
        // Resources allocated in this function are freed in the CExampleWsClient destructor            
        iMainWindow=new (ELeave) CMainWindow(this);
        iMainWindow->ConstructL(iRect, TRgb (255,255,255));
        }

/****************************************************************************\
|       Function:       CExampleWsClient::HandleKeyEventL()
|       Purpose:        Processes key events for CExampleWsClient
\****************************************************************************/
void CExampleWsClient::HandleKeyEventL (TKeyEvent& /*aKeyEvent*/)
        {
        }


/****************************************************************************\
|       Function:       CExampleWsClient::RunL()
|                               Called by active scheduler when an even occurs
|       Purpose:        Processes events according to their type
|                               For key events: calls HandleKeyEventL() (global to client)
|                               For pointer event: calls HandlePointerEvent() for window
|                                  event occurred in.
\****************************************************************************/
void CExampleWsClient::RunL()
        {
        // get the event
        iWs.GetEvent(iWsEvent);
        TInt eventType=iWsEvent.Type();
        // take action on it
        switch (eventType)
                {
        // events global within window group
        case EEventNull:
        case EEventKey:
        case EEventModifiersChanged:
        case EEventKeyUp:
        case EEventKeyDown:
        case EEventFocusLost:
        case EEventFocusGained:
        case EEventSwitchOn:
        case EEventPassword:
        case EEventWindowGroupsChanged:
        case EEventErrorMessage:
                break;
        // events local to specific windows
        case EEventPointer:
                {
                CWindow* window=(CWindow*)(iWsEvent.Handle()); // get window
                TPointerEvent& pointerEvent=*iWsEvent.Pointer();
                window->HandlePointerEvent (pointerEvent);
                break;
                }
        case EEventPointerExit:
        case EEventPointerEnter:
                break;
        case EEventPointerBufferReady:
                {
                CWindow* window=(CWindow*)(iWsEvent.Handle()); // get window
                window->HandlePointerMoveBufferReady ();
                break;
                }
        case EEventDragDrop:
                break;
        default:
                break;
                }
        IssueRequest(); // maintain outstanding request
        }

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