求索阁

81. 如何用键盘滚动分割的视口?
我的问题是当我用鼠标滚动分割窗口时,视口滚动都很正常,但用键盘时,却什么也没有发生.
在你的视图继承类中加入如下两个函数,假定该类为CScrollerView:
void CScrollerView::OnKeyDown(UINT nChar, UINT nRepCnt, UINT nFlags)
{
BOOL processed;
for (unsigned int i=0;i< nRepCnt&&processed;i++)
processed=KeyScroll(nChar);
if (!processed)
  CScrollView::OnKeyDown(nChar, nRepCnt, nFlags);
}
BOOL CScrollerView::KeyScroll(UINT nChar)
{
switch (nChar)
{
case VK_UP:
OnVScroll(SB_LINEUP,0,NULL);
break;
case VK_DOWN:
OnVScroll(SB_LINEDOWN,0,NULL);
break;
case VK_LEFT:
OnHScroll(SB_LINELEFT,0,NULL);
break;
case VK_RIGHT:
OnHScroll(SB_LINERIGHT,0,NULL);
break;
case VK_HOME:
OnHScroll(SB_LEFT,0,NULL);
break;
case VK_END:
OnHScroll(SB_RIGHT,0,NULL);
break;
case VK_PRIOR:
OnVScroll(SB_PAGEUP,0,NULL);
break;
case VK_NEXT:
OnVScroll(SB_PAGEDOWN,0,NULL);
break;
default:
return FALSE; // not for us
  // and let the default class
  // process it.
}
  return TRUE;
}
82. 如何改变默认的光标形状?
我试着将光标改变为其它的形状和颜色,但却没有变化.
在对话框/窗口/你需要的地方加上对WM_SETCURSOR消息的处理.
BOOL MyDialog::OnSetCursor(CWnd* pWnd, UINT nHitTest, UINT message)
{
// TOD Add your message handler code here and/or call default
::SetCursor(AfxGetApp()->LoadCursor(IDC_MYCURSOR));
return TRUE;
//return CDialog::OnSetCursor(pWnd, nHitTest, message);
}
你没有成功的原因是因为窗口类光标风格不能为NULL.
83. 如何选择CTreeCtrl中的节点文本进行编辑?
在向CTreeCtrl中加入一项后,有什么方法可以编辑该节点的文本呢?
首先设置你的CcompTreeCtrl具有TVS_EDITLABELS属性.在设计时用控件属性来设置在运行时用GetStyle()/SetStyle()成员函数来设置.然后请看下述代码:
HTREEITEM CCompTreeCtrl::AddSet()
{
static int setCnt =3D 1;
HTREEITEM hItem;
CString csSet;
//create text for new note: New Set 1, New Set 2 ...
csSet.Format( _T( "New Set %d" ), setCnt++ );
hItem =3D InsertItem( csSet, IMG_CLOSEDFOLDER, IMG_CLOSEDFOLDER );
if( hItem !=3D NULL )
  EditLabel( hItem );
return hItem;
}
84. CListCtrl中选择变化时如何获得通知?
我在Report View中使用了一个CListCtrl(自绘制类型),我想知道什么时候选择项发生了改变.
在选择项变化时,可以使用按钮有效或失效,按如下操作:
加入LVN_ITEMCHANGED消息处理.
void CYourClassNameHere::OnItemchangedEventList(NMHDR* pNMHDR, LRESULT* pResult)
{
NM_LISTVIEW* pNMListView = (NM_LISTVIEW*)pNMHDR;
*pResult = 0;
if (pNMListView->uChanged == LVIF_STATE)
{
if (pNMListView->uNewState)
  GetDlgItem(IDC_DELETE)->EnableWindow(TRUE);
else
  GetDlgItem(IDC_DELETE)->EnableWindow(FALSE);
}
}
85. List控件中整栏选择?
我在处理List控件时碰到了麻烦,我想创建一个ListView,来依据Tree控件的选择同时在ListView和ReportView中显示列表的信息.以下是相关的代码:
// Set full line select
ListView_SetExtendedListViewStyle(m_plstCustomers->GetSafeHwnd(),
LVS_EX_FULLROWSELECT);
按如下方法处理:
// -------------------- begin of snippet --------------------------------
bool CCommCtrlUtil32::ListCtrl_ModifyExtendedStyle(CListCtrl& p_rListCtrl,
  const DWORD p_dwStyleEx,
  const bool p_bAdd)
{
HWND t_hWnd = p_rListCtrl.GetSafeHwnd();
DWORD t_dwStyleEx = ListView_GetExtendedListViewStyle(t_hWnd);
if(p_bAdd)
{
if(0 == (p_dwStyleEx & t_dwStyleEx))
{
// add style
t_dwStyleEx |= p_dwStyleEx;
}
}
else
{
if(0 != (p_dwStyleEx & t_dwStyleEx))
{
// remove style
t_dwStyleEx &= ~p_dwStyleEx;
}
}
ListView_SetExtendedListViewStyle(t_hWnd, t_dwStyleEx);
return true;
}
86. 如何限制mdi子框架最大化时的大小?
用ptMaxTrackSize代替prMaxSize,如下所示:
void CChildFrame::OnGetMinMaxInfo(MINMAXINFO FAR* lpMMI)
{
  // TOD Add your message handler code here and/or call default
  CChildFrame::OnGetMinMaxInfo(lpMMI);
  lpMMI->ptMaxTrackSize.x = 300;
  lpMMI->ptMaxTrackSize.y = 400;
}
87. 怎样实现3D效果？
在对话框中怎样实现Edit和Listboxes控件的3D效果?(环境95/NT VC5.0)
1). 使用带WS_EX_CLIENTEDGE标志的::CreateWindowEx来替换::CreateWindow 或者用CWnd::CreateEx替换CWnd::Create.
2).在建立控件之后,调用ModifyStyleEx(0, WS_EX_CLIENTEDGE).
88. How do I update the text of a pane in a status bar?
By default, a CStatusBar pane is not enabled when the pane is created. To activate a pane, you must call the ON_UPDATE_COMMAND_UI() macro for each pane on the status bar and update the panes. Because panes do not send WM_COMMAND messages, you cannot use ClassWizard to activate panes; you must type the code manually. For example, suppose one pane has ID_INDICATOR_PAGE as its identifier and that it contains the current page number in a document. To make the ID_INDICATOR_PAGE pane display text, add the following to a header file (probably the MAINFRM.H file):
afx_msg void OnUpdatePage(CCmdUI *pCmdUI);
Add the following to the application message map:
ON_UPDATE_COMMAND_UI(ID_INDICATOR_PAGE, OnUpdatePage)
Add the following to a source code file (probably MAINFRM.CPP):
void CMainFrame::OnUpdatePage(CCmdUI *pCmdUI)
{
pCmdUI->Enable();
}
To display text in the panes, either call SetPaneText() or call CCmdUI::SetText() in the OnUpdate() function. For example, you might want to set up an integer variable m_nPage that contains the current page number. Then, the OnUpdatePage() function might read as follows:
void CMainFrame::OnUpdatePage(CCmdUI *pCmdUI)
{
pCmdUI->Enable();
char szPage[16];
wsprintf((LPSTR)szPage, "Page %d", m_nPage);
pCmdUI->SetText((LPSTR)szPage);
}
This technique causes the page number to appear in the pane during idle processing in the same manner that the application updates other indicators.
89. 动态修改对话框的大小
[问题提出]
关于如何动态改变对话框的大小,我做了个Demo,大家看看.
[程序实现]
  //本函数使用方法： 
  //第一个参数：如果是TRUE表示显示扩展的对话框，如果是FALSE,表示缩小对话框。 
  //第二个参数：表示本对话框的HWND， 
  //第三个参数：表示缩小后大小的控件的ID
void COptionDlg::ExpandBox(BOOL fExpand, HWND hwnd, int nIDDefaultBox)
{
  CWnd *pWndBox=GetDlgItem(nIDDefaultBox);
  RECT rcDefaultBox,rcChild,rcIntersection,rcWnd;
  pWndBox->GetWindowRect(&rcDefaultBox);
  HWND hwndChild = ::GetTopWindow(hwnd);
  for (; hwndChild != NULL; hwndChild = ::GetNextWindow(hwndChild,GW_HWNDNEXT)) 
  {
::GetWindowRect(hwndChild, &rcChild);
if (!IntersectRect(&rcIntersection, &rcChild, &rcDefaultBox))
  ::EnableWindow(hwndChild, fExpand);
  }
  ::GetWindowRect(hwnd, &rcWnd);
  if (GetWindowLong(hwnd, GWL_USERDATA) == 0)
  {
SetWindowLong(hwnd, GWL_USERDATA,
  MAKELONG(rcWnd.right - rcWnd.left, 
  rcWnd.bottom - rcWnd.top));
::ShowWindow(pWndBox->m_hWnd, SW_HIDE);
  }
  ::SetWindowPos(hwnd, NULL, 0, 0,
rcDefaultBox.right - rcWnd.left,
rcDefaultBox.bottom - rcWnd.top,
SWP_NOZORDER | SWP_NOMOVE);
  if(fExpand)
  {
DWORD dwDims = GetWindowLong(hwnd, GWL_USERDATA);
::SetWindowPos(hwnd, NULL, 0, 0,
  LOWORD(dwDims), HIWORD(dwDims), SWP_NOZORDER | SWP_NOMOVE);
::SendMessage(hwnd, DM_REPOSITION, 0, 0);
  }
}
90. 用DoModal()调用模态对话框，总是显示在正中，我重载了它，并添加了MoveWindow(),可是其m_hWnd是一串零，调用失败。请问有何方法可使调用的模态对话框显示于自定义位置？多谢
我不清楚你把MoveWindow()加在什么地方了，正确的方法是在OnInitDialog中添加MoveWindow，如： 
  MoveWindow(0, 1, 300, 200); 
需要注意的是前两个参数不能都为0。如果你确实希望把窗口放在(0, 0)处，可以在对话框设计窗口的属性中选中Absolute Align，然后再加入 
  MoveWindow(0, 0, 300, 200); 
为什么会是这样？你看了MFC的源程序就会明白。原来MFC在调用你的OnInitDialog之后，会调用CDialog::CheckAutoCenter()