C++ wxEraseEvent::GetDC方法代码示例

// the event handler executed when the window background must be painted
void wxWindow::OnErase(wxEraseEvent& event)
{
    if ( !m_renderer )
    {
        event.Skip();

        return;
    }

    DoDrawBackground(*event.GetDC());

#if wxUSE_SCROLLBAR
    // if we have both scrollbars, we also have a square in the corner between
    // them which we must paint
    if ( m_scrollbarVert && m_scrollbarHorz )
    {
        wxSize size = GetSize();
        wxRect rectClient = GetClientRect(),
               rectBorder = m_renderer->GetBorderDimensions(GetBorder());

        wxRect rectCorner;
        rectCorner.x = rectClient.GetRight() + 1;
        rectCorner.y = rectClient.GetBottom() + 1;
        rectCorner.SetRight(size.x - rectBorder.width);
        rectCorner.SetBottom(size.y - rectBorder.height);

        if ( GetUpdateRegion().Contains(rectCorner) )
        {
            m_renderer->DrawScrollCorner(*event.GetDC(), rectCorner);
        }
    }
#endif // wxUSE_SCROLLBAR
}

void wxSplashScreenWindow::OnEraseBackground(wxEraseEvent& event)
{
    if (event.GetDC() && m_bitmap.IsOk())
    {
        wxDrawSplashBitmap(* event.GetDC(), m_bitmap, 0, 0);
    }
    else
    {
        wxClientDC dc(this);
        if (m_bitmap.IsOk())
            wxDrawSplashBitmap(dc, m_bitmap, 0, 0);
    }
}

void CPanelPreferences::OnEraseBackground( wxEraseEvent& event ) {
    if (!m_backgroundBitmap) {
        MakeBackgroundBitmap();
    }
    // Create a buffered device context to reduce flicker
    wxSize sz = GetClientSize();
    wxBufferedDC dc(event.GetDC(), sz, wxBUFFER_CLIENT_AREA);

#if TEST_BACKGROUND_WITH_MAGENTA_FILL
    // Fill the dialog with a magenta color so people can detect when something
    //   is wrong
    dc.SetBrush(wxBrush(wxColour(255,0,255)));
    dc.SetPen(wxPen(wxColour(255,0,255)));
    dc.DrawRectangle(0, 0, sz.GetWidth(), sz.GetHeight());
#else
    CSkinSimple* pSkinSimple = wxGetApp().GetSkinManager()->GetSimple();
    
    wxASSERT(pSkinSimple);
    wxASSERT(wxDynamicCast(pSkinSimple, CSkinSimple));

    wxColour bgColor(*pSkinSimple->GetDialogBackgroundImage()->GetBackgroundColor());
    SetBackgroundColour(bgColor);
#endif

    if (m_backgroundBitmap->IsOk()) {
       dc.DrawBitmap(*m_backgroundBitmap, 0, 0);
    }
}

void AboutBox::OnEraseBackground(wxEraseEvent& event)
{
	wxPoint ptWnd;
	wxSize 	seWnd;

	ptWnd   = wxPoint(-1,-1);//GetPosition();
	seWnd   = GetClientSize();
	wxDC *pDC = event.GetDC();
	if (pDC)
	{
		pDC->SetBrush(m_brGrey);
		pDC->DrawRectangle(ptWnd.x, ptWnd.y, 2+seWnd.GetWidth(), 2+seWnd.GetHeight());
		pDC->SetBrush(m_brStipple);
		pDC->DrawRectangle(m_rect1.GetX(), m_rect1.GetY(), m_rect1.GetWidth(), m_rect1.GetHeight());
		pDC->SetBrush(m_brWhite);
		pDC->DrawRectangle(m_rect2.GetX(), m_rect2.GetY(), m_rect2.GetWidth(), m_rect2.GetHeight());
		pDC->SetBrush(wxNullBrush);
	}
	else
	{
		wxClientDC dc(this);
		dc.SetBrush(m_brGrey);
		dc.DrawRectangle(ptWnd.x, ptWnd.y, 2+seWnd.GetWidth(), 2+seWnd.GetHeight());
		dc.SetBrush(m_brStipple);
		dc.DrawRectangle(m_rect1.GetX(), m_rect1.GetY(), m_rect1.GetWidth(), m_rect1.GetHeight());
		dc.SetBrush(m_brWhite);
		dc.DrawRectangle(m_rect2.GetX(), m_rect2.GetY(), m_rect2.GetWidth(), m_rect2.GetHeight());
		dc.SetBrush(wxNullBrush);
	}	                            
}

// -------------------------------------------------------------------------------- //
void guSplashFrame::OnEraseBackground( wxEraseEvent &event )
{
    wxDC * dc = event.GetDC();
    if( dc )
    {
        dc->DrawBitmap( * m_Bitmap, 0, 0, false );
    }
}

void CScrolledTextBox::OnEraseBackground(wxEraseEvent& event) {
    wxDC *dc = event.GetDC();
    wxPoint p = GetParent()->GetPosition();
    wxRect r = GetRect();
    r.Offset(p);
    wxBitmap backgroundBitmap = ((CSimpleTaskPanel*)GetGrandParent())->GetBackgroundBmp().GetSubBitmap(r);
    dc->DrawBitmap(backgroundBitmap, 0, 0);
}

void DispLoading::onEraseBG( wxEraseEvent& event )
{
	wxDC *dc = event.GetDC();

	if (!m_imgHandle.getImg() || !m_imgHandle->IsOk())
	{
		dc->SetTextForeground(wxColor(0,0,0));
		dc->Clear();
		return;
	}

	int h = GetSize().GetHeight();
	int w = GetSize().GetWidth();
	int iw = m_imgHandle->GetSize().GetWidth();


	//size 7
	const int l_start = 0;
	const int l_width = 2;

	//size 6
	const int m_start = 2;
	const int m_width = 15;

	//size 7 with 1 pix gap
	const int r_start = 17;
	const int r_width = 2;


	wxBitmap   tmpBmp(w, h);
	wxMemoryDC tmpDC(tmpBmp);

	tmpDC.SetBrush(wxBrush(wxColor(255,0,255)));
	tmpDC.SetPen( wxPen(wxColor(255,0,255),1) );
	tmpDC.DrawRectangle(0,0,w,h);

	wxImage scaled = m_imgHandle->Scale(iw, h);

	if (scaled.IsOk())
	{
		wxBitmap left = wxBitmap(scaled.GetSubImage( wxRect(l_start,0,l_width,h)) );
		wxBitmap right = wxBitmap(scaled.GetSubImage( wxRect(r_start,0,r_width,h)) );
		wxBitmap center(w-(l_width+r_width),h);

		wxColor c(255,0,255);
		gcImage::tileImg(center, wxBitmap(scaled.GetSubImage( wxRect(m_start,0,m_width,h)) ), &c);

		tmpDC.DrawBitmap(left, l_start,0,true);
		tmpDC.DrawBitmap(center, m_start,0,true);
		tmpDC.DrawBitmap(right, w-r_width,0,true);
	}

	tmpDC.SelectObject(wxNullBitmap);
	dc->DrawBitmap(tmpBmp, 0,0, true);

	wxRegion region = wxRegion(tmpBmp, wxColor(255,0,255), 1);
	SetShape(region, this);
}

void CProjectsComponent::OnEraseBackground(wxEraseEvent& event){
    CSkinSimple* pSkinSimple = wxGetApp().GetSkinManager()->GetSimple();

    wxASSERT(pSkinSimple);
    wxASSERT(wxDynamicCast(pSkinSimple, CSkinSimple));

	wxDC* dc = event.GetDC();
    dc->DrawBitmap(*pSkinSimple->GetProjectAreaBackgroundImage()->GetBitmap(), 0, 0);
}

void cbSplashScreen::OnEraseBackground(wxEraseEvent &event)
{
  wxDC *dc = event.GetDC();

  if (dc)
  {
    DoPaint(*dc); // why not? :)
  }
}

void wxControl::OnEraseBackground( wxEraseEvent& rEvent )
{
    RECTL                           vRect;
    HPS                             hPS = rEvent.GetDC()->GetHPS();
    SIZEL                           vSize = {0,0};

    ::GpiSetPS(hPS, &vSize, PU_PELS | GPIF_DEFAULT);
    ::WinQueryWindowRect((HWND)GetHwnd(), &vRect);
    ::WinFillRect(hPS, &vRect, GetBackgroundColour().GetPixel());
} // end of wxControl::OnEraseBackground

void wxEmulatorContainer::OnEraseBackground(wxEraseEvent& event)
{
    wxDC* dc wxDUMMY_INITIALIZE(NULL);

    if (event.GetDC())
    {
        dc = event.GetDC();
    }
    else
    {
        dc = new wxClientDC(this);
    }

    dc->SetBackground(wxBrush(wxGetApp().m_emulatorInfo.m_emulatorBackgroundColour, wxSOLID));
    dc->Clear();

    if (!event.GetDC())
        delete dc;
}

void MyCanvas::OnEraseBackground(wxEraseEvent& event)
{
    if (wxGetApp().GetBackgroundBitmap().Ok())
    {
        wxSize sz = GetClientSize();
        wxRect rect(0, 0, sz.x, sz.y);

        if (event.GetDC())
        {
            wxGetApp().TileBitmap(rect, *(event.GetDC()), wxGetApp().GetBackgroundBitmap());
        }
        else
        {
            wxClientDC dc(this);
            wxGetApp().TileBitmap(rect, dc, wxGetApp().GetBackgroundBitmap());
        }
    }
    else
        event.Skip(); // The official way of doing it
}

void BaseToolBarControl::onEraseBG(wxEraseEvent& event)
{
	if (!m_imgBg.getImg() || !m_imgBg->IsOk())
	{
		event.Skip();
	}
	else
	{
		wxDC *dc = event.GetDC();
		wxBitmap temp(m_imgBg->Scale(GetSize().GetWidth(), GetSize().GetHeight()));
		dc->DrawBitmap(temp, 0,0, false);
	}
}

// We don't reliably get EraseBackground events under Linux, 
// so there is a workaround at CSimplePanelBase::MakeBGBitMap()
void CSimpleGUIPanel::OnEraseBackground(wxEraseEvent& event) {
    wxDC *dc = event.GetDC();
    
#ifdef __WXMAC__
    // Avoid unnecessary drawing due to Mac progress indicator's animation
    wxRect clipRect;
    wxRect taskRect = m_taskPanel->GetRect();
    dc->GetClippingBox(&clipRect.x, &clipRect.y, &clipRect.width, &clipRect.height);
    if (clipRect.IsEmpty() || taskRect.Contains(clipRect)) {
        return;
    }
#endif
    dc->DrawBitmap(m_bmpBg, 0, 0);
}

void ClientStateIndicator::OnEraseBackground(wxEraseEvent& event){
    CSkinSimple* pSkinSimple = wxGetApp().GetSkinManager()->GetSimple();

    wxASSERT(pSkinSimple);
    wxASSERT(wxDynamicCast(pSkinSimple, CSkinSimple));

	event.Skip(false);
	wxDC *dc;
	dc=event.GetDC();
	dc->SetBackground(wxBrush(this->GetBackgroundColour(),wxSOLID));
	dc->Clear();
    dc->DrawBitmap(*(pSkinSimple->GetWorkunitAreaBackgroundImage()->GetBitmap()), 0, 0); 

}