如何加入位图，并能够对它进行拖动

Question

如何加入位图，并能够对它进行拖动，而且，需要在相应鼠标事件后，自动加入位图，如左键点击之后

Answer 1

这不难吧。我这儿有一个CDib类，要不要。要，给我来个信息吧。

Answer 2

要，我的e_mail是[email protected]。有用一定给分。谢谢！！

Answer 3

应该不会很难吧!在相应的鼠标响应函数里GetDC来加载位图，不行么？试试看？

Answer 4

我用SDK写过，MFC也是类似的方式。载入的是1024*768图
LRESULT CALLBACK  WinProc(HWND  hwnd,UINT msg,WPARAM wParam,LPARAM lParam)
{
static HBITMAP  hBit;
PAINTSTRUCT     ps;
HDC    hdc;
static POINT  oldPt,newPt,OriginPt;
static BOOL   flag=FALSE;
HDC    memdc;
    HINSTANCE       hInstance;
static int      cxClient,cyClient;
int    cx,cy;
    static int mincx,mincy;
switch(msg)
{
case WM_CREATE:
hInstance=((LPCREATESTRUCT)lParam)->hInstance;
        hBit=LoadBitmap(hInstance,MAKEINTRESOURCE(IDB_BACK));
return 0;
case WM_SIZE:
cxClient=LOWORD(lParam);
cyClient=HIWORD(lParam);
        OriginPt.x=OriginPt.y=0;
        mincx=cxClient-1024;
mincy=cyClient-768;
return 0;
    case WM_LBUTTONDOWN:
newPt.x=LOWORD(lParam);
newPt.y=HIWORD(lParam);
oldPt=newPt;
flag=TRUE;
return 0;
case WM_LBUTTONUP:
flag=FALSE;
return 0;
case WM_MOUSEMOVE:
if(flag)
{
newPt.x=LOWORD(lParam);
newPt.y=HIWORD(lParam);
if(newPt.x !=oldPt.x || newPt.y != oldPt.y )
{
hdc=GetDC(hwnd);
cx=newPt.x-oldPt.x;
cy=newPt.y-oldPt.y;
OriginPt.x +=cx;
OriginPt.y +=cy;
if(OriginPt.x<=mincx)
{
cx=0;
OriginPt.x=mincx;
}
if(OriginPt.x >=0)
{
cx=0;
OriginPt.x=0;
} if(OriginPt.y<=mincy)
{
cy=0;
OriginPt.y=mincy;
}
if(OriginPt.y >=0 )
{
cy=0;
OriginPt.y=0;
}
ScrollDC(hdc,cx,cy,NULL,NULL,NULL,NULL);
InvalidateRect(hwnd,NULL,FALSE);
ReleaseDC(hwnd,hdc);
oldPt=newPt;
}
}
return 0; case WM_PAINT:
hdc=BeginPaint(hwnd,&ps);
        if(hBit)
{
memdc=CreateCompatibleDC(hdc);
SelectObject(memdc,hBit);
            BitBlt(hdc,0,0,1024,768,memdc,-OriginPt.x,-OriginPt.y,SRCCOPY);
DeleteDC(memdc);
}
EndPaint(hwnd,&ps);
return 0;
case WM_DESTROY:
DeleteObject(hBit);
PostQuitMessage(0);
return 0;
}
return DefWindowProc(hwnd,msg,wParam,lParam);
}