Introduction
I wrote this many years ago for a friend. It is basically just a normal pushbutton, except that when the user tries to click on it, it moves out of the way making it practically un-clickable.
I have no idea what anyone would ever want to use such a control in their app, apart from wanting to be extremely annoying to users (and hey - don't we all get like that on occasion?) :)
The button is just a normal button with OnMouseMove
overridden: (m_nJumpDistance
is the distance in pixels to jump once the mouse has moved over the control).
The WM_SETFOCUS
message has also been handled to bounce the focus back to the window that previously had focus, and PreSubclassWindow
has been overridden to allow the removal of the WS_TABSTOP
window style bit. This ensures that the user can't tab to the control.
The guts of it all
void CTrickButton::OnMouseMove(UINT nFlags, CPoint point)
{
CWnd* pParent = GetParent();
if (!pParent) pParent = GetDesktopWindow();
CRect ParentRect; pParent->GetClientRect(ParentRect);
ClientToScreen(&point); pParent->ScreenToClient(&point);
CRect ButtonRect; GetWindowRect(ButtonRect);
pParent->ScreenToClient(ButtonRect);
CPoint Center = ButtonRect.CenterPoint();
CRect NewButtonRect = ButtonRect;
if (point.x > Center.x) {
if (ButtonRect.left > ParentRect.left + ButtonRect.Width() + m_nJumpDistance)
NewButtonRect -= CSize(ButtonRect.right - point.x + m_nJumpDistance, 0);
else
NewButtonRect += CSize(point.x - ButtonRect.left + m_nJumpDistance, 0);
}
else if (point.x < Center.x) {
if (ButtonRect.right < ParentRect.right - ButtonRect.Width() - m_nJumpDistance)
NewButtonRect += CSize(point.x - ButtonRect.left + m_nJumpDistance, 0);
else
NewButtonRect -= CSize(ButtonRect.right - point.x + m_nJumpDistance, 0);
}
if (point.y > Center.y) {
if (ButtonRect.top > ParentRect.top + ButtonRect.Height() + m_nJumpDistance)
NewButtonRect -= CSize(0, ButtonRect.bottom - point.y + m_nJumpDistance);
else
NewButtonRect += CSize(0, point.y - ButtonRect.top + m_nJumpDistance);
}
else if (point.y < Center.y) {
if (ButtonRect.bottom < ParentRect.bottom - ButtonRect.Height() - m_nJumpDistance)
NewButtonRect += CSize(0, point.y - ButtonRect.top + m_nJumpDistance);
else
NewButtonRect -= CSize(0, ButtonRect.bottom - point.y + m_nJumpDistance);
}
MoveWindow(NewButtonRect);
RedrawWindow();
CButton::OnMouseMove(nFlags, point);
}
void CTrickButton::OnSetFocus(CWnd* pOldWnd)
{
CButton::OnSetFocus(pOldWnd);
if (pOldWnd!=NULL && ::IsWindow(pOldWnd->GetSafeHwnd()))
pOldWnd->SetFocus();
}
void CTrickButton::PreSubclassWindow()
{
ModifyStyle(WS_TABSTOP, 0);
CButton::PreSubclassWindow();
}
History
31 May 2002 - updated to include removal of WM_TABSTOP
, plus minor cleanup.
Chris Maunder is the co-founder of
CodeProject, DeveloperMedia and ContentLab, and has been a prominent figure in the software development community for nearly 30 years. Hailing from Australia, Chris has a background in Mathematics, Astrophysics, Environmental Engineering and Defence Research. His programming endeavours span everything from FORTRAN on Super Computers, C++/MFC on Windows, through to to high-load .NET web applications and Python AI applications on everything from macOS to a Raspberry Pi. Chris is a full-stack developer who is as comfortable with SQL as he is with CSS.
In the late 1990s, he and his business partner David Cunningham recognized the need for a platform that would facilitate knowledge-sharing among developers, leading to the establishment of CodeProject.com in 1999. Chris's expertise in programming and his passion for fostering a collaborative environment have played a pivotal role in the success of CodeProject.com. Over the years, the website has grown into a vibrant community where programmers worldwide can connect, exchange ideas, and find solutions to coding challenges. Chris is a prolific contributor to the developer community through his articles and tutorials, and his latest passion project,
CodeProject.AI.
In addition to his work with CodeProject.com, Chris co-founded ContentLab and DeveloperMedia, two projects focussed on helping companies make their Software Projects a success. While at CodeProject, Chris' roles included Architecture and coding, Product Development, Content Creation, Community Growth, Client Satisfaction and Systems Automation, and many, many sales meetings. All while keeping his sense of humour.