Dialog Boxes and Property Sheets

1
Dialog Boxes andProperty Sheets

• Jim Fawcett
• CSE791 Advanced Windows Programming
• Summer 2002

2
References

• Programming Windows with MFC, Jeff Prosise, 2nd
  Edition, Microsoft Press, 1999
• Derived from presentations by Kevin Devaney and
  Ciahua Wang, 2001

3
Dialog Boxes

• Modal
• Owner window disabled until dialog closed
• Modeless
• Owner window can be reactivated while dialog is
  still open
• Property Sheets
• Dialog boxes with tabbed pages

4
Class Hierarchy
5
Example Dialog Box

• Font dialog
• Controls
• Combo boxes
• List boxes
• Check boxes
• Push buttons

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Create a Simple Dialog App

• Use MFC AppWizard
• Visual C Menu
• File / New / MFC AppWizard
• Step 0 - Define project name and location
• Step 1 Choose Dialog-based
• Other Steps Accept defaults

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Using MFC AppWizard
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Add Dialog Controls

• Use toolbar to select controls for your dialog
• Click on the control you want
• Click on the dialog where you want to put the
  control
• Drag mouse on edges of the control to resize it
• Right-click on control, select properties and
  provide new ID

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Dialog Resource File (.rc)

• IDD_CREDIT_DIALOG DIALOGEX 0, 0, 265, 154
• STYLE DS_MODALFRAME WS_MINIMIZEBOX WS_POPUP
  WS_VISIBLE WS_CAPTION WS_SYSMENU
• EXSTYLE WS_EX_APPWINDOW
• CAPTION "Credit Card Calculator"
• FONT 8, "MS Sans Serif"
• BEGIN
• DEFPUSHBUTTON "Calculate",IDOK,198,102,41,14
  
• PUSHBUTTON "Exit",IDCANCEL,198,126,41,14
• CONTROL "Spin1",IDC_SPIN_DEBT,"msctls_
  updown32",UDS_ARROWKEYS,21,22,11,14
• END

Resource file has dialog template Dialog box
characteristics (popup) Types of controls used
in the dialog (spin) Control position, size,
characteristics
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Adding Shortcut Keys
Right-click on control and select Properties
Exit
Alt-E will activate the Exit button
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Setting Tab Order
In Visual C menu, choose Layout/Tab Order
Current tab order will be shown
Click on controls in desired order to set a new
tab order
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Responding to User Input

• Double-click on the control
• Add Member Function dialog will pop up
• Select OK and it will create a function for
  that control
• OnOK for OK button
• OnChangeEditXxxx for edit control
• Add code to the function to perform needed
  processing

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Temperature Converter
IDC_EDIT_INPUT
IDC_EDIT_OUTPUT
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OnOK Processing
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How to talk to controls - 1

• Use CWnd functions
• GetDlgItemText, SetDlgItemText
• CheckRadioButton, GetCheckedRadioButton
• CheckDlgButton, IsDlgButtonChecked
• This was illustrated in Temperature Converter
  example

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How to talk to controls - 2

• Use info supplied in the message handler

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How to talk to controls - 3

• Use common control classes
• CEdit, CListBox, CComboBox, CSliderCtrl, etc
• Use CWnd Attach function to associate control
  class with your control

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Common Control Class Example
Remember to use Detach function if you create
the object on the stack
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How to talk to controls - 4

• Use Dynamic Data Exchange
• Override virtual function DoDataExchange
• Use DDX functions to associate member variables
  with controls
• Exchange occurs
• Input (variable to control) in OnInitDialog
• Output (control to variable) in OnOK

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DDX Example
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DDX Functions

• DDX_Text Edit control
• DDX_Check Check box
• DDX_Radio Radio box
• DDX_LBIndex, DDX_LBString List box
• DDX_CBIndex, DDX_CBString Combo box
• DDX_Scroll Scroll bar

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Dynamic Data Validation

• Dynamic data validation (DDV) works similar to
  DDX
• DDV checks that input data is within specified
  limits
• If data is outside limits, focus is passed to the
  control and an error message is displayed

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DDV Example
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DDV Functions

• DDV_MinMaxByte, DDV_MinMaxInt,
• DDV_MinMaxLong, DDV_MinMaxUInt,
• DDV_MinMaxDWord, DDV_MinMaxFloat,
• DDV_MinMaxDouble, DDV_MaxChars

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Modal vs Modeless

• Modal
• Display dialog by calling CDialogDoModal
• Exit by calling CDialogOnOK or OnCancel
• Usually instantiated on the stack so destruction
  is automatic

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Modal vs Modeless

• Modeless
• Display dialog by calling CDialogCreate
• Exit dialog by calling DestroyWindow
• Dont call OnOK or OnCancel
• Usually instantiated on the heap (new) so the
  dialog is not destroyed prematurely
• Make sure dialog is deleted by overriding
  CDialogPostNcDestroy function using delete
  this statement

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Basic Modal Dialog Programming (see example p.
398)

• Declare dialog member variables in header file
  (.h)
• Initialize variables and setup controls in
  OnInitDialog
• Use Class Wizard to create message handler
  functions that get user input
• Perform data processing in OnOK andcomment out
  call to CdialogOnOK()

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Property Sheets

• Tabbed dialog boxes
• User can switch between pages using mouse
• MFC classes
• CPropertySheet
• CPropertyPage

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Property Sheets

• Is a tabbed dialog box containing pages of
  controls that user can switch among.
• Encapsulated in a pair of MFC classes
  CPropertySheet and CPropertyPage
• CPropertySheet represents the property sheet
  itself
• CPropertyPage represents a page in the property
  sheet.
• Property sheets can be modal or modeless, created
  with DoMomal() or Create()

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How to Create a Modal Property Sheet

• For each page create a dialog template.
• For each page derive a dialog-like class from
  CPropertyPage that include public members linked
  to the pages controls via DDX or DDV.
• Derive a property sheet class from
  CPropertySheet.
• Use CPropertySheetAddPage() to add pages to the
  property sheet.
• Call the property sheets DoModal() to display
  the property sheet.

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How to Create a Modal Property Sheet (cont.)

• MFC CPropertySheet provide functions for three
  buttons -- OK, Cancel and Apply.
• Property sheet pages should not include OK or
  Cancel button --when the property sheets OK
  buton is clicked, the current pages OnOK() is
  called.
• Add message handler for Apply button, which
  should call the active pages UpdateData(TRUE).
• Use CPropertyPages SetModified() to enable or
  disable Apply button.

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How to Create a Modal Property Sheet (cont.)

• class CFirstPagepublic CPropertyPage
• public .
• // delare member here
• ptotected
• virtual void DoDataExchange(CDataExchange)
  .
• class CMyPropertySheetpublic CProperySheet
• CFirstPage m_firstPage // first
  page ..
• public .
• CMyPropertySheet() // constructor
• AddPage(m_firstPage) .

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Common Dialogs

• CFileDialog
• CPrintDialog
• CPageSetupDialog
• CFindReplaceDialog
• CColorDialog
• CFontDialog

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CFileDialog
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CFileDialog code
TCHAR szFilters _T("Text files
(.txt).txtAll files (.).") CFileDialog
dlg(TRUE, _T("txt"), _T(".txt"),
OFN_FILEMUSTEXIST OFN_HIDEREADONLY,
szFilters) if( dlg.DoModal() IDOK )
filename dlg.GetPathName()