用鼠标拖动图片移动Drag the picture move with mouseDrag the picture to respond to the 3 mouse message
OnLBut t onD own, OnLBut t onUp, OnMous eMove
When the left button is pressed:
To determine if the image is pressed inside the image, if youcapture the picture
When the left key is released:
Release pictures
Mouse movement: according to the movement of the mouse,real-time redraw pictures
For this purpose, three class variables are set:
CPoint Pt; / / save the starting point
BOOL bcapture; / / image capture
CSize offsetsize; //offset of the mouse and the starting pointof the picture
The first is initialization:
[cpp] view plaincopyprint?
CMovePictureView: : CMovePictureView ()
{
Add construction code here / / TODO:
Bcapture=FALSE;
Pt.x=0;
Pt.y=0;
Offsetsize.cx=0;
Offsetsize.cy=0;
}
Then respond to the OnLButtonDown message
[cpp] view plaincopyprint?
Void CMovePictureView: : OnLButtonDown (UINT nFlags, CPointpoint)
{
CRect selrc (PT, size) ;
CClientDC DC (this) ;
OnPrepareDC (&dc) ;
CRgn rgn;
Rgn.CreateRectRgnIndirect (&selrc) ;
If (rgn.PtInRegion (point))
{
SetCapture () ;
B c ap tur e=T RUE;
CPoint RCPT (PT) ;
Offsetsize=point-rcpt;
SetCursor (LoadCursor (NULL, IDC_CROSS) ) ;
}
CScrollView: : OnLButtonDown (nFlags, point) ;
}
Respond to UP messages
[cpp] view plaincopyprint?
Void CMovePictureView: : OnLButtonUp (UINT nFlags, CPointpoint)
{
ReleaseCapture () ;
Bcapture=FALSE;
CScrollView: : OnLButtonUp (nFlags, point) ;
}
Respond to Move messages
[cpp] view plaincopyprint?
Void CMovePictureView: : OnMouseMove (UINT nFlags, CPointpoint)
{
If (bcapture)
{
CClientDC DC (this) ;
OnPrepareDC (&dc) ;
CRect oldrc (PT, size) ;
InvalidateRect (oldrc, TRUE) ;
Pt=point-offsetsize;
CRect newrc (PT, size) ;
InvalidateRect (newrc, TRUE) ;
}
CScrollView: : OnMouseMove (nFlags, point) ;
}
If you're drawing in the whole view or drawing in the entiredialog box, you can move the picture. But, if you're drawingin the CStatic picture control in the dialog box, there' s aproblem.
The reason is that: the mouse in response to the news, thecoordinates of CPoint points are the coordinates of the clientarea (dialog box because the response is a mouse message dialogbox so the coordinate system is a coordinate system, and thedialog box) our map is a CSTATIC picture control coordinatesystem and two coordinate systems are different, so there wasconfusion, cause we can not achieve the results you want.Solution: when the mouse message is received, screencoordinates are used as intermediate media. Specifically asfollows: first converts the CPoint from the dialog coordinatesystem to the screen coordinate system, and then converts thescreen coordinate system to the control coordinate system
[cpp] view plaincopyprint?
Void CShowImageDlg: : OnLButtonDown (UINT nFlags, CPoint point){
TODO: / / add your message handler code here and / or calldefault
CPoint orgPoint=point;
This->ClientToScreen (&point) ; //dialog box coordinates intoscreen coordinates
M_image.ScreenToClient (&point) ; / / screen coordinates intothe control coordinate system
CRect selRc (m_pt, m_size) ; / / coordinate control
CRgn rgn;
Rgn.CreateRectRgnIndirect (&selRc) ;
If (rgn.PtInRegion (point)) / / in the judgment of thecoordinate control, so you should first convert point tocoordinate control
{
SetCapture () ;
M_bc apt ure=TRUE;
CPoint RCPT (m_pt) ;
M_offsetsize=point-rcpt;
SetCursor (LoadCursor (NULL, IDC_CROSS) ) ;
}
CDialog: : OnLButtonDown (nFlags, orgPoint) ;
}
[cpp] view plaincopyprint?
Void CShowImageDlg: : OnLButtonUp (UINT nFlags, CPoint point){
TODO: / / add your message handler code here and / or calldefault
ReleaseCapture () ;
M_bcapture=FALSE;
CDialog: : OnLButtonUp (nFlags, point) ;
}
[cpp] view plaincopyprint?
Void CShowImageDlg: : OnMouseMove (UINT nFlags, CPoint point){
TODO: / / add your message handler code here and / or calldefault
CPoint orgPoint=point;
This->ClientToScreen (&point) ;
M_image.ScreenToClient (&point) ;
If (m_bcapture)
{
CRect oldRc (m_pt, m_size) ; / / coordinate control
M_image.ClientToScreen (&oldRc) ; / / into screen coordinatesThis->ScreenToClient (&oldRc) ; / / convert dialog boxcoordinates, then call the right InvalidateRect (oldRc, TRUE) ;because this function is invoked in the dialog box, so thedialog box coordinates coordinates
InvalidateRect (oldRc, TRUE) ;
M_pt=point-m_offsetsize;
CRect newRc (m_pt, m_size) ;
M_image.ClientToScreen (&newRc) ; // the same, will coordinatecontrol of newRc into the dialog box coordinates conversion,can call the InvalidateRect function correctly
This->ScreenToCl ient (&newRc) ;
InvalidateRect (newRc, TRUE) ;
}
CDialog: : OnMouseMove (nFlags, orgPoint) ;
}
AlphaVPS是一家保加利亚本土主机商(DA International Group Ltd),提供VPS主机及独立服务器租用等,数据中心包括美国(洛杉矶/纽约)、德国、英国和保加利亚等,公司办公地点跟他们提供的保加利亚数据中心在一栋楼内,自有硬件,提供IPv4+IPv6,支持PayPal或者信用卡等方式付款。商家提供的大硬盘VPS主机,提供128GB-2TB磁盘,最低年付15欧元起,也可以选择...
Megalayer 商家算是比较新晋的国内主机商,主要方向是美国、香港、菲律宾等机房的独立服务器为主,以及站群服务器和显卡服务器。同时也有新增价格并不是特别优惠的VPS云服务器。上午的时候有网友问问有没有CN2线路的美国独立服务器的,这里我推荐他选择Megalayer看看,目前也是有活动截止到月底的。Megalayer 商家创办2年左右时间,如果我们初次使用建议月付体验。目前在进行且可能截止到6月...
青云互联怎么样?青云互联是一家成立于2020年的主机服务商,致力于为用户提供高性价比稳定快速的主机托管服务,目前提供有美国免费主机、香港主机、韩国服务器、香港服务器、美国云服务器,香港安畅cn2弹性云限时首月五折,15元/月起;可选Windows/可自定义配置,让您的网站高速、稳定运行。点击进入:青云互联官方网站地址青云互联优惠码:八折优惠码:ltY8sHMh (续费同价)青云互联香港云服务器活动...