Article source: http://blog.csdn.net/cddchina/article/details/25394143
Author: cddchina
In order to reduce the size of the client, consider changing some background images to tiled display.
GDI+ is a new interface provided by Microsoft in operating systems after Windows 2000. It is based on object-oriented, while GDI is based on functions.
It is recommended that you use GDI+ to draw pictures. GDI+ is easy to use. The following is how GDI+ and GDI are used.
Instructions for using GDI+:
void CDlgClassroom::OnPaint()
{
if (IsIconic())
{
CPaintDC dc(this); // device context for painting
SendMessage(WM_ICONERASEBKGND, reinterpret_cast<WPARAM>(dc.GetSafeHdc()), 0);
// Center icon in client rectangle
int cxIcon = GetSystemMetrics(SM_CXICON);
int cyIcon = GetSystemMetrics(SM_CYICON);
CRect rect;
GetClientRect(&rect);
int x = (rect.Width() - cxIcon + 1) / 2;
int y = (rect.Height() - cyIcon + 1) / 2;
// Draw the icon
dc.DrawIcon(x, y, m_hIcon);
}
else
{
CPaintDC dc(this);
CRect rect;
GetClientRect(&rect);//The current position of the dialog box
Graphics graphics(dc.m_hDC);
ImageAttributes imAtt;
imAtt.SetWrapMode(WrapModeTile); //Stretch the picture
// stretch the image
Bitmap backgroundtop(L".\\classroom\\class_toolbar_top.png"); //Load PNG image
graphics.DrawImage(&backgroundtop,Rect(0,0,rect.Width(),34),
0, 0,backgroundtop.GetWidth(),backgroundtop.GetHeight(),UnitPixel,&imAtt);
////////////// tile background image
// Bitmap backgroundmiddle(L".\\room\\BgBlackboard.png");//Load PNG image
// TextureBrush brush(&backgroundmiddle, WrapModeTile/*FlipXY*/ );
// graphics.FillRectangle(&brush, RectF(0.0f, 0.0f,rect.Width(),rect.Height()));
CDialog::OnPaint();
}
}
GDI uses:
GDI is more complicated to operate.
voidCDlgClassroom::OnPaint()
{
if (IsIconic())
{
CPaintDC dc(this); // device context for painting
SendMessage(WM_ICONERASEBKGND, reinterpret_cast<WPARAM>(dc.GetSafeHdc()), 0);
// Center icon in client rectangle
int cxIcon = GetSystemMetrics(SM_CXICON);
int cyIcon = GetSystemMetrics(SM_CYICON);
CRect rect;
GetClientRect(&rect);
intx = (rect.Width() - cxIcon + 1) / 2;
inty = (rect.Height() - cyIcon + 1) / 2;
// Draw the icon
dc.DrawIcon(x, y, m_hIcon);
}
else
{
CPaintDC dc(this);
CRect rect;
GetClientRect(&rect);//对话框当前位置
//平铺图片
CDC MemDC;
CBitmap cbitmap;
CBitmap* pOldBmp = NULL;
HBITMAP hBitmap;
CDC * pDC = GetDC();
//顶部背景图
Bitmap backgroundtop(L".\\classroom\\class_toolbar_top.png"); //Load PNG image
backgroundtop.GetHBITMAP(Color(0,0,0),&hBitmap); // Bitmap To HBITMAP
CBitmap* cBitmap = CBitmap::FromHandle(hBitmap); // HBITMAP To CBitmap *
MemDC.CreateCompatibleDC(pDC); // Display picture
pOldBmp = MemDC.SelectObject(cBitmap);
dc.StretchBlt(0,0,rect.Width(),34, &MemDC, 0, 0,backgroundtop.GetWidth() ,backgroundtop.GetHeight(),SRCCOPY);
MemDC.SelectObject(pOldBmp);//releaseDC
MemDC.DeleteDC();
cBitmap->DeleteObject();
CDialog::OnPaint();
}
}