apb.htm

Visual C++ 6.0 21天自学教程 一本适合初学和对c++有一定基础的人学习的好书

    ///////////////////////
    CFileDialog m_ldFile(TRUE);
    // Show the File open dialog and capture the result
    if (m_ldFile.DoModal() == IDOK)
    {
        // Get the filename selected
        m_sResults = m_ldFile.GetPathName();
        // Update the dialog
        UpdateData(FALSE);
    }
    ///////////////////////
    // MY CODE ENDS HERE
    ///////////////////////
</PRE>
<PRE>}
</PRE>

<DL>
	<DT></DT>
	<DD>The GetPathName function returns the path and filename, so changing the function
	call from GetFileName to GetPathName alters the display to include the path with
	the filename.
	<P>
	<DT></DT>
	<DD><B>2. </B>Add a button on the custom dialog that calls the MessageBox function
	with a Yes or No selection. Pass the result back to the main application dialog.
	<P>
	<DT></DT>
	<DD>Follow these steps:
	<P>
	<DT></DT>
	<DD><B>1. </B>Using the Class View, add a member variable to the CMsgDlg class. Specify
	the variable type as int, the name as m_iYesNo, and the access as Public.
	<P>
	<DT></DT>
	<DD><B>2. </B>Using the Resource View, bring the custom dialog into the editor area.
	Add a command button to the window, named IDC_YESNO with a caption &amp;Yes or No.
	<P>
	<DT></DT>
	<DD><B>3. </B>Using the Class Wizard, add a function to the new button you just added
	and edit the function. Include the following code:
	<P>
</DL>

<PRE>void CMsgDlg::OnYesno() 
{
    // TODO: Add your control notification handler code here
    ///////////////////////
    // MY CODE STARTS HERE
    ///////////////////////
    // Ask the user
    m_iYesNo = MessageBox(&quot;Choose Yes or No&quot;, &quot;Yes or No&quot;, &Acirc;MB_YESNO);
    ///////////////////////
    // MY CODE ENDS HERE
    ///////////////////////
</PRE>
<PRE>}
</PRE>

<DL>
	<DT></DT>
	<DD><B>4. </B>Add a button to the main dialog window named IDC_YESNO with the caption
	Y&amp;es or No.
	<P>
	<DT></DT>
	<DD><B>5. </B>Using the Class Wizard, add a function to the new button, including
	the following code:
	<P>
</DL>

<PRE>void CDialogsDlg::OnYesno() 
{
    // TODO: Add your control notification handler code here
    ///////////////////////
    // MY CODE STARTS HERE
    ///////////////////////
    // What did the user answer
    switch (m_dMsgDlg.m_iYesNo)
    {
    case IDYES:    // Did the user answer YES?
        m_sResults = &quot;Yes!&quot;;
        break;
    case IDNO:     // Did the user answer NO?
        m_sResults = &quot;No!&quot;;
        break;
</PRE>
<PRE><B>}</B></PRE>
<P>
<PRE>    // Update the dialog
    UpdateData(FALSE);
    ///////////////////////
    // MY CODE ENDS HERE
    ///////////////////////
</PRE>
<PRE>}
</PRE>
<H2><A NAME="Heading16"></A>Day 6</H2>
<H3>Quiz</H3>

<DL>
	<DT></DT>
	<DD><B>1. </B>What event message does a menu selection send to the window message
	queue?
	<P>
	<DT></DT>
	<DD>COMMAND.
	<P>
	<DT></DT>
	<DD><B>2. </B>How do you attach a menu to a dialog window?
	<P>
	<DT></DT>
	<DD>In the dialog designer, open the properties dialog for the window, and choose
	the menu from the drop-down list of menus.
	<P>
	<DT></DT>
	<DD><B>3. </B>Which existing class do you specify for handling event messages for
	the menu?
	<P>
	<DT></DT>
	<DD>The dialog class for the window on which the menu appears.
	<P>
	<DT></DT>
	<DD><B>4. </B>What event message should a pop-up menu be triggered by?
	<P>
	<DT></DT>
	<DD>The WM_CONTEXTMENU event.
	<P>
</DL>

<H3>Exercises</H3>

<DL>
	<DT></DT>
	<DD><B>1. </B>Add a button to the main window and have it call the same function
	as the Hello menu entry.
	<P>
	<DT></DT>
	<DD>Follow these steps:
	<P>
	<DT></DT>
	<DD><B>1. </B>Add a button to the dialog screen. Supply a button ID of IDC_HELLO
	and a caption of &amp;Hello.
	<P>
	<DT></DT>
	<DD><B>2. </B>Using the Class Wizard, add a function to the button. Name the function
	OnHello.
	<P>
	<DT></DT>
	<DD><B>2. </B>Add a pop-up menu to your application that uses the Help drop-down
	menu as the pop-up menu.
	<P>
	<DT></DT>
	<DD>Follow these steps:
	<P>
	<DT></DT>
	<DD><B>1. </B>Using the Class Wizard, add a function for the WM_CONTEXTMENU event
	message in your dialog window.
	<P>
	<DT></DT>
	<DD><B>2. </B>Edit the function, adding the following code:
	<P>
</DL>

<PRE>void CMenusDlg::OnContextMenu(CWnd* pWnd, CPoint point)
{
    // TODO: Add your message handler code here and/or call &Acirc;default
    ///////////////////////
    // MY CODE STARTS HERE
    ///////////////////////
    // Declare local variables
    CMenu *m_lMenu;    // A pointer to the menu
    CPoint m_pPoint;    // A copy of the mouse position
    // Copy the mouse position to a local variable
    m_pPoint = point;
    // Convert the position to a screen position
    ClientToScreen(&amp;m_pPoint);
    // Get a pointer to the window menu
    m_lMenu - GetMenu();
    // Get a pointer to the first submenu
    m_lMenu = m_lMenu-&gt;GetSubMenu(1);
    // Show the Pop-up Menu
    m_lMenu-&gt;TrackPopupMenu(TPM_CENTERALIGN + TPM_LEFTBUTTON,
        m_pPoint.x, m_pPoint.y, this, NULL);
    ///////////////////////
    // MY CODE ENDS HERE
    ///////////////////////
    CDialog::OnRButtonDown(nFlags, point);
</PRE>
<PRE>}
</PRE>
<H2><A NAME="Heading19"></A>Day 7</H2>
<H3>Quiz</H3>

<DL>
	<DT></DT>
	<DD><B>1. </B>How can you specify that the text is to be underlined?
	<P>
	<DT></DT>
	<DD>Pass 1 as the value for the bUnderline argument to the CreateFont function.
	<P>
	<DT></DT>
	<DD><B>2. </B>How can you print your text upside down?
	<P>
	<DT></DT>
	<DD>Pass 1800 as the nEscapement argument to the CreateFont function.
	<P>
	<DT></DT>
	<DD><B>3. </B>How many times is the EnumFontFamProc callback function called by the
	operating system?
	<P>
	<DD>The function is called once for each font that is available in the system, unless
	the callback function returns 0 and stops the listing of fonts.
</DL>

<H3>Exercises</H3>

<DL>
	<DT></DT>
	<DD><B>1. </B>Add a check box to switch between using the entered text to display
	the font and using the font name to display the font, as in Figure 7.4.
	<P>
	<DT></DT>
	<DD>Add the check box to the dialog. Set its properties as follows:
	<P>
	<DT></DT>
	<DD>ID: IDC_CBUSETEXT
	<P>
	<DT></DT>
	<DD>Caption: &amp;Use Entered Text
	<P>
	<DT></DT>
	<DD>Using the Class Wizard, attach a variable to this control. Specify the variable
	type as a boolean with the name m_bUseText.
	<P>
	<DT></DT>
	<DD>Using the Class Wizard, add a function for the BN_CLICKED event message for the
	check box. Edit the function, adding the following code:
	<P>
</DL>

<PRE>void CDay7Dlg::OnCbusetext()
{
    // TODO: Add your control notification handler code here
    ///////////////////////
    // MY CODE STARTS HERE
    ///////////////////////
    // Update the variables with the dialog controls
    UpdateData(TRUE);
    // Using the font name for the font sample?
    if (!m_bUseText)
        // Using the font name
        m_strDisplayText = m_strFontName;
    else
        // Using the entered text
        m_strDisplayText = m_strSampText;
    // Update the dialog
    UpdateData(FALSE);
    ///////////////////////
    // MY CODE ENDS HERE
    ///////////////////////
</PRE>
<PRE>}
</PRE>

<DL>
	<DT></DT>
	<DD>Modify the OnInitDialog function to initialize the check box as follows:
	<P>
</DL>

<PRE>BOOL CDay7Dlg::OnInitDialog()
{
    CDialog::OnInitDialog();
.
.
.
    // TODO: Add extra initialization here
    ///////////////////////
    // MY CODE STARTS HERE
    ///////////////////////
    // Fill the font list box
    FillFontList();
    // Initialize the text to be entered
    m_strSampText = &quot;Testing&quot;;
    // Copy the text to the font sample area
    m_strDisplayText = m_strSampText;
    // Initialize the check box
    m_bUseText = TRUE;
    // Update the dialog
    UpdateData(FALSE);
    ///////////////////////
    // MY CODE ENDS HERE
    ///////////////////////
    return TRUE;  // return TRUE  unless you set the focus 
                  // to a control
</PRE>
<PRE>}
</PRE>

<DL>
	<DT></DT>
	<DD>Modify the OnSelchangeLfonts function as follows:
	<P>
</DL>

<PRE>void CDay7Dlg::OnSelchangeLfonts()
{
    // TODO: Add your control notification handler code here
    ///////////////////////
    // MY CODE STARTS HERE
    ///////////////////////
    // Update the variables with the dialog controls
    UpdateData(TRUE);
    // Using the font name for the font sample?
    if (!m_bUseText)
    {
        // Copy the font name to the font sample
        m_strDisplayText = m_strFontName;
        // Update the dialog with the variables
        UpdateData(FALSE);
    }
    // Set the font for the sample
    SetMyFont();
    ///////////////////////
    // MY CODE ENDS HERE
    ///////////////////////
</PRE>
<PRE>}
</PRE>

<DL>
	<DT></DT>
	<DD>Finally, modify the OnChangeEsamptext function as follows:
	<P>
</DL>

<PRE>void CDay7Dlg::OnChangeEsamptext()
{
    // TODO: If this is a RICHEDIT control, the control will not
    // send this notification unless you override the 
    // CDialog::OnInitialUpdate()
    // function and call CRichEditCrtl().SetEventMask()
    // with the EN_CHANGE flag ORed into the mask.
    // TODO: Add your control notification handler code here
    ///////////////////////
    // MY CODE STARTS HERE
    ///////////////////////
    // Update the variables with the dialog controls
    UpdateData(TRUE);
    // Using the text for the font sample?
    if (m_bUseText)
    {
        // Copy the current text to the font sample
        m_strDisplayText = m_strSampText;
        // Update the dialog with the variables
        UpdateData(FALSE);
    }
    ///////////////////////
    // MY CODE ENDS HERE
    ///////////////////////
</PRE>
<PRE>}
</PRE>

<DL>
	<DT></DT>
	<DD><B>2. </B>Add a check box to display the font sample in italics, as in Figure
	7.5.
	<P>
	<DT></DT>
	<DD>Add the check box to the dialog. Set its properties as follows:
	<P>
	<DT></DT>
	<DD>ID: IDC_CBITALIC
	<P>
	<DT></DT>
	<DD>Caption: &amp;Italic
	<P>
	<DT></DT>
	<DD>Using the Class Wizard, attach a variable to this control. Specify the variable
	type as a boolean with the name m_bItalic.
	<P>
	<DT></DT>
	<DD>Using the Class Wizard, add a function for the BN_CLICKED event message for the
	check box. Edit the function, adding the following code:
	<P>
</DL>

<PRE>void CDay7Dlg::OnCbitalic()
{
    // TODO: Add your control notification handler code here
    ///////////////////////
    // MY CODE STARTS HERE
    ///////////////////////
    // Update the variables with the dialog controls
    UpdateData(TRUE);
    // Set the font for the sample
    SetMyFont();
    ///////////////////////
    // MY CODE ENDS HERE
    ///////////////////////
</PRE>
<PRE>}
</PRE>

<DL>
	<DT></DT>
	<DD>Modify the SetMyFont function as in the following code:
	<P>
</DL>

<PRE>void CDay7Dlg::SetMyFont()
{
    CRect rRect;        // The rectangle of the display area
    int iHeight;        // The height of the display area
    int iItalic = 0;    // Italicize the font?
    // Has a font been selected?
    if (m_strFontName != &quot;&quot;)
    {
        // Get the dimensions of the font sample display area
        m_ctlDisplayText.GetWindowRect(&amp;rRect);
        // Calculate the area height
        iHeight = rRect.top - rRect.bottom;
        // Make sure the height is positive
        if (iHeight &lt; 0)
            iHeight = 0 - iHeight;
        // Should the font be italicized?
        If (m_bItalic)
            iItalic = 1;
        // Create the font to be used
        m_fSampFont.CreateFont((iHeight - 5), 0, 0, 0, 
                FW_NORMAL, iItalic, 0, 0, DEFAULT_CHARSET, 
                OUT_CHARACTER_PRECIS, CLIP_CHARACTER_PRECIS, 
                DEFAULT_QUALITY, DEFAULT_PITCH |
                FF_DONTCARE, m_strFontName);
        // Set the font for the sample display area
        m_ctlDisplayText.SetFont(&amp;m_fSampFont);
    }
</PRE>
<PRE>}
</PRE>
<H2><A NAME="Heading22"></A>Day 8</H2>
<H3>Quiz</H3>

<DL>
	<DT></DT>
	<DD><B>1. </B>What are the three values that are combined to specify a color?
	<P>
	<DT></DT>
	<DD>Red, green, and blue.
	<P>
	<DT></DT>
	<DD><B>2. </B>What do you use to draw on windows without needing to know what graphics
	card the user has?
	<P>
	<DT></DT>