在对话框里的一个名为IDC_RESULT的static Text控件里作图,三种图形选择,点击确定键作图,代码如下:
void CDrawDlg::OnPaint()
{
CWnd* pWnd=GetDlgItem(IDC_RESULT); CPaintDC dcPaint(pWnd);
CPen pen(PS_SOLID,2,RGB(0,0,0));
dcPaint.SelectObject(&pen);
CRect rect;
pWnd->GetClientRect(&rect);
if(isLine)
{
//MessageBox(_T("isLine"));
InvalidateRect(rect, false);
//UpdateWindow(); dcPaint.MoveTo(10,150);
dcPaint.LineTo (350,150);
} if(isRect)
{
//MessageBox(_T("isRect")); dcPaint.Rectangle(50, 100, 300, 200);
}
if(isSineFunction)
{
double y;
for(int x= 0;x < 360; x++)
{
y = sin(x*2*3.14/360) * 100 + 100;
dcPaint.LineTo(x,y);
}
} ReleaseDC(&dcPaint); if (IsIconic())
{
MessageBox(_T("OnPaint"));
CPaintDC dc(this); // 用于绘制的设备上下文 SendMessage(WM_ICONERASEBKGND, reinterpret_cast<WPARAM>(dc.GetSafeHdc()), 0); // 使图标在工作区矩形中居中
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; // 绘制图标
dc.DrawIcon(x, y, m_hIcon);
}
else
{
CDialogEx::OnPaint();
}
}
..................
void CDrawDlg::OnBnClickedOk()
{
Invalidate(false);
//Invalidate(true);
UpdateWindow();
}void CDrawDlg::OnBnClickedRadioLine()
{
isLine = true;
isRect = false;
isSineFunction = false;
}void CDrawDlg::OnBnClickedRadioRect()
{
isLine = false;
isRect = true;
isSineFunction = false;
}void CDrawDlg::OnBnClickedRadio()
{
isLine = false;
isRect = false;
isSineFunction = true;
}
问题一、error C3861: “sin”: 找不到标识符,已经包含了头文件math.h
问题二、想在点击确定键换另外一个图形是把static text控件上的原有图形擦出,于是试图用InvalidateRect来实现,但是不知道为什么只能擦出一半。
新手
void CDrawDlg::OnPaint()
{
CWnd* pWnd=GetDlgItem(IDC_RESULT); CPaintDC dcPaint(pWnd);
CPen pen(PS_SOLID,2,RGB(0,0,0));
dcPaint.SelectObject(&pen);
CRect rect;
pWnd->GetClientRect(&rect);
if(isLine)
{
//MessageBox(_T("isLine"));
InvalidateRect(rect, false);
//UpdateWindow(); dcPaint.MoveTo(10,150);
dcPaint.LineTo (350,150);
} if(isRect)
{
//MessageBox(_T("isRect")); dcPaint.Rectangle(50, 100, 300, 200);
}
if(isSineFunction)
{
double y;
for(int x= 0;x < 360; x++)
{
y = sin(x*2*3.14/360) * 100 + 100;
dcPaint.LineTo(x,y);
}
} ReleaseDC(&dcPaint); if (IsIconic())
{
MessageBox(_T("OnPaint"));
CPaintDC dc(this); // 用于绘制的设备上下文 SendMessage(WM_ICONERASEBKGND, reinterpret_cast<WPARAM>(dc.GetSafeHdc()), 0); // 使图标在工作区矩形中居中
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; // 绘制图标
dc.DrawIcon(x, y, m_hIcon);
}
else
{
CDialogEx::OnPaint();
}
}
..................
void CDrawDlg::OnBnClickedOk()
{
Invalidate(false);
//Invalidate(true);
UpdateWindow();
}void CDrawDlg::OnBnClickedRadioLine()
{
isLine = true;
isRect = false;
isSineFunction = false;
}void CDrawDlg::OnBnClickedRadioRect()
{
isLine = false;
isRect = true;
isSineFunction = false;
}void CDrawDlg::OnBnClickedRadio()
{
isLine = false;
isRect = false;
isSineFunction = true;
}
问题一、error C3861: “sin”: 找不到标识符,已经包含了头文件math.h
问题二、想在点击确定键换另外一个图形是把static text控件上的原有图形擦出,于是试图用InvalidateRect来实现,但是不知道为什么只能擦出一半。
新手
invalidateRect的矩形参数怎么给出的?
{
CWnd* pWnd=GetDlgItem(IDC_RESULT); pWnd->Invalidate();
pWnd->UpdateWindow();
...
invalidateRect的矩形参数:
if(isLine)
{
//MessageBox(_T("isLine"));
InvalidateRect(rect, false);//InvalidateRect
//UpdateWindow();dcPaint.MoveTo(10,150);
dcPaint.LineTo (350,150);}
问math.h在哪里包含的,是要看你的#include代码
//
#include <math.h>
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