Code: Select all
CBitmap BarBitmap;
CDC BarDC;
RECT rect;
rect.left = m_TrackPos.x + m_TrackBarCentrePos.x * m_TrackUnitLength - m_TrackBarWidth / 2;
rect.right = rect.left + m_TrackBarWidth;
rect.top = m_TrackBarCentrePos.y;
rect.bottom = m_TrackBarCentrePos.y + m_TrackBarHeight;
BarDC.CreateCompatibleDC( &painDC );
BarBitmap.CreateCompatibleBitmap( &painDC,m_TrackBarWidth, m_TrackBarHeight );
CBitmap* pOldBarBitmap = BarDC.SelectObject( &BarBitmap );
CBrush BarBrush;
RECT BarRect;
BarRect.left = 0;
BarRect.top = 0;
BarRect.right = m_TrackBarWidth;
BarRect.bottom = m_TrackBarHeight;
BarBrush.CreateSolidBrush( m_BarColorBk );
BarDC.FillRect( &BarRect, &BarBrush );
BarBrush.DeleteObject( );
BarDC.Draw3dRect( &BarRect, m_TrackBarTrackFrameColor, m_TrackBarTrackFrameColor );
BLENDFUNCTION BlendFun;
ZeroMemory( &BlendFun, sizeof( BlendFun ) );
BlendFun.BlendOp = AC_SRC_OVER;
BlendFun.AlphaFormat = 0;
BlendFun.SourceConstantAlpha = 180;
MemDC.AlphaBlend(
rect.left,
rect.top,
m_TrackBarWidth,
m_TrackBarHeight,
&BarDC,
0,
0,
m_TrackBarWidth,
m_TrackBarHeight,
BlendFun );
BarDC.SelectObject( pOldBarBitmap );
BarBitmap.DeleteObject( );
BarDC.DeleteDC( );
painDC.BitBlt( 0, 0, ClientRect.right, ClientRect.bottom, &MemDC, 0, 0, SRCCOPY );
MemDC.SelectObject( pOldBitmap );
MemBitmap.DeleteObject( );
MemDC.DeleteDC( );EDIT by Auria : please use code tags