skinhorizontalscrollbar.cpp

windows ce 6.0下的实现Listctrl自画

// SkinHorizontalScrollbar.cpp : implementation file
//

#include "stdafx.h"
#include "CE6_ListCtrl_HideScrollBar.h"
#include "SkinHorizontalScrollbar.h"

#ifdef _DEBUG
#define new DEBUG_NEW
#undef THIS_FILE
static char THIS_FILE[] = __FILE__;
#endif 

/////////////////////////////////////////////////////////////////////////////
// CSkinHorizontalScrollbar

CSkinHorizontalScrollbar::CSkinHorizontalScrollbar()
{
    nThumbLeft = 25;
    dbThumbRemainder = 0.00f;

    bMouseDown = false;
    bMouseDownArrowLeft = false;
    bMouseDownArrowRight = false;
    bDragging = false;
    pList = NULL;
}

CSkinHorizontalScrollbar::~CSkinHorizontalScrollbar(){}


BEGIN_MESSAGE_MAP(CSkinHorizontalScrollbar, CStatic)
//{{AFX_MSG_MAP(CSkinHorizontalScrollbar)
    ON_WM_PAINT()
    ON_WM_LBUTTONDOWN()
    ON_WM_LBUTTONUP()
    ON_WM_MOUSEMOVE()
    ON_WM_TIMER()
//}}AFX_MSG_MAP
END_MESSAGE_MAP()

/////////////////////////////////////////////////////////////////////////////
// CSkinHorizontalScrollbar message handlers

void CSkinHorizontalScrollbar::OnPaint()
{
    CPaintDC dc(this); // device context for painting

    Draw();
}

void CSkinHorizontalScrollbar::OnLButtonDown(UINT nFlags, CPoint point)
{
    SetCapture();
    CRect clientRect;
    GetClientRect(&clientRect);

    int nWidth = clientRect.Width() - 26;

    CRect rectLeftArrow(0, 0, 26, 20);
    CRect rectRightArrow(nWidth, 0, nWidth + 26, 20);
    CRect rectThumb(nThumbLeft, 0, nThumbLeft + 26, 20);

    if (rectThumb.PtInRect(point))
    {
        bMouseDown = true;
    }

    if (rectRightArrow.PtInRect(point))
    {
        bMouseDownArrowRight = true;
        SetTimer(2, 250, NULL);
    }

    if (rectLeftArrow.PtInRect(point))
    {
        bMouseDownArrowLeft = true;
        SetTimer(2, 250, NULL);
    }

    CStatic::OnLButtonDown(nFlags, point);
}

void CSkinHorizontalScrollbar::OnLButtonUp(UINT nFlags, CPoint point)
{
    UpdateThumbPosition();
    KillTimer(1);
    ReleaseCapture();

    bool bInChannel = true;

    CRect clientRect;
    GetClientRect(&clientRect);

    int nWidth = clientRect.Width() - 26;

    CRect rectLeftArrow(0, 0, 26, 20);
    CRect rectThumb(nThumbLeft, 0, nThumbLeft + 26, 20);

    if (rectLeftArrow.PtInRect(point))
    {
        ScrollLeft();
        bInChannel = false;
    }

    CRect rectRightArrow(nWidth, 0, nWidth + 26, 20);


    if (rectRightArrow.PtInRect(point))
    {
        ScrollRight();
        bInChannel = false;
    }

    if (rectThumb.PtInRect(point))
    {
        bInChannel = false;
    }

    if (bInChannel == true && !bMouseDown)
    {
        if (point.x > nThumbLeft)
        {
            PageRight();
        }
        else
        {
            PageLeft();
        }
    }

    // reset all variables
    bMouseDown = false;
    bDragging = false;
    bMouseDownArrowLeft = false;
    bMouseDownArrowRight = false;
    CStatic::OnLButtonUp(nFlags, point);
}

void CSkinHorizontalScrollbar::OnMouseMove(UINT nFlags, CPoint point)
{
    CRect clientRect;
    GetClientRect(&clientRect);

    if (bMouseDown)
        bDragging = true;

    if (bDragging)
    {
        nThumbLeft = point.x - 13; //-13 so mouse is in middle of thumb

        double nMax = pList->GetScrollLimit(SB_HORZ);
        int nPos = pList->GetScrollPos(SB_HORZ);

        double nWidth = clientRect.Width() - 75;
        double nVar = nMax;
        dbThumbInterval = nWidth / nVar;

        //figure out how many times to scroll total from top
        //then minus the current position from it
        int nScrollTimes = (int)((nThumbLeft - 25) / dbThumbInterval) - nPos;

        CSize size;
        size.cx = nScrollTimes;
        size.cy = 0;

        pList->Scroll(size);

        LimitThumbPosition();

        Draw();
    }

    CStatic::OnMouseMove(nFlags, point);
}

void CSkinHorizontalScrollbar::OnTimer(UINT nIDEvent)
{
    if (nIDEvent == 1)
    {
        if (bMouseDownArrowRight)
        {
            ScrollRight();
        }

        if (bMouseDownArrowLeft)
        {
            ScrollLeft();
        }
    }
    else if (nIDEvent == 2)
    {
        if (bMouseDownArrowRight)
        {
            KillTimer(2);
            SetTimer(1, 50, NULL);
        }

        if (bMouseDownArrowLeft)
        {
            KillTimer(2);
            SetTimer(1, 50, NULL);
        }
    }
    CStatic::OnTimer(nIDEvent);
}

void CSkinHorizontalScrollbar::ScrollLeft()
{
    pList->SendMessage(WM_HSCROLL, MAKELONG(SB_LINELEFT, 0), NULL);
    UpdateThumbPosition();
}

void CSkinHorizontalScrollbar::ScrollRight()
{
    pList->SendMessage(WM_HSCROLL, MAKELONG(SB_LINERIGHT, 0), NULL);
    UpdateThumbPosition();
}

void CSkinHorizontalScrollbar::UpdateThumbPosition()
{
    CRect clientRect;
    GetClientRect(&clientRect);

    double nPos = pList->GetScrollPos(SB_HORZ);
    double nMax = pList->GetScrollLimit(SB_HORZ);
    double nWidth = clientRect.Width() - 75;
    double nVar = nMax;

    dbThumbInterval = nWidth / nVar;

    double nNewdbValue = dbThumbInterval * (nPos);
    int nNewValue = (int)nNewdbValue;
    double nExtra = nNewdbValue - nNewValue;
    dbThumbRemainder = nExtra;

    nThumbLeft = 25 + nNewValue;

    LimitThumbPosition();

    Draw();
}

void CSkinHorizontalScrollbar::PageRight()
{
    pList->SendMessage(WM_HSCROLL, MAKELONG(SB_PAGEDOWN, 0), NULL);
    UpdateThumbPosition();
}

void CSkinHorizontalScrollbar::PageLeft()
{
    pList->SendMessage(WM_HSCROLL, MAKELONG(SB_PAGEUP, 0), NULL);
    UpdateThumbPosition();
}

void CSkinHorizontalScrollbar::Draw()
{
    CClientDC dc(this);
    CRect clientRect;
    GetClientRect(&clientRect);
    CMemDC memDC(&dc, &clientRect);
    memDC.FillSolidRect(&clientRect, RGB(76, 85, 118));

    CDC bitmapDC;
    bitmapDC.CreateCompatibleDC(&dc);

    //draw left arrow of scrollbar
    CBitmap bitmap;
    bitmap.LoadBitmap(IDB_HORIZONTAL_SCROLLBAR_LEFTARROW);
    CBitmap *pOldBitmap = bitmapDC.SelectObject(&bitmap);

    memDC.BitBlt(clientRect.left, clientRect.top, 26, 12, &bitmapDC, 0, 0,
        SRCCOPY);

    bitmapDC.SelectObject(pOldBitmap);
    bitmap.DeleteObject();
    pOldBitmap = NULL;


    bitmap.LoadBitmap(IDB_HORIZONTAL_SCROLLBAR_SPAN);

    pOldBitmap = bitmapDC.SelectObject(&bitmap);


    int nWidth = clientRect.Width() - 26;

    memDC.StretchBlt(clientRect.left + 26, clientRect.top, nWidth, 12, 
        &bitmapDC, 0, 0, 1, 12, SRCCOPY);

    bitmapDC.SelectObject(pOldBitmap);
    bitmap.DeleteObject();
    pOldBitmap = NULL;

    bitmap.LoadBitmap(IDB_HORIZONTAL_SCROLLBAR_RIGHTARROW);

    pOldBitmap = bitmapDC.SelectObject(&bitmap);
    memDC.BitBlt(nWidth, clientRect.top, 26, 12, &bitmapDC, 0, 0, SRCCOPY);

    bitmapDC.SelectObject(pOldBitmap);
    bitmap.DeleteObject();
    pOldBitmap = NULL;

    //If there is nothing to scroll then don't
    //show the thumb control otherwise show it
    if (pList->GetScrollLimit(SB_HORZ) != 0)
    {
        bitmap.LoadBitmap(IDB_HORIZONTAL_SCROLLBAR_THUMB);

        pOldBitmap = bitmapDC.SelectObject(&bitmap);
        memDC.BitBlt(clientRect.left + nThumbLeft, clientRect.top, 26, 12, 
            &bitmapDC, 0, 0, SRCCOPY);

        bitmapDC.SelectObject(pOldBitmap);
        bitmap.DeleteObject();
        pOldBitmap = NULL;
    }
}

void CSkinHorizontalScrollbar::LimitThumbPosition()
{
    CRect clientRect;
    GetClientRect(&clientRect);

    if (nThumbLeft + 26 > (clientRect.Width() - 26))
    {
        nThumbLeft = clientRect.Width() - 51;
    }

    if (nThumbLeft < (clientRect.left + 25))
    {
        nThumbLeft = clientRect.left + 25;
    }
}