Chapter 7 Controls

Introduction MFC Classic Controls Control Type WNDCLASS MFC Class Buttons "BUTTON" CButton List boxes "LISTBOX" CListBox Edit controls "EDIT" CEdit Combo boxes "COMBOBOX" CComboBox Scroll bars "SCROLLBAR" CScrollBar Static controls "STATIC" CStatic

How it works Controls and its parent window Notification Message When its states change Example) A button is being clicked Member Functions of the control Change or get the state of the control. Example) Change a button to be inactive Controls (Child Window) Parent Window ① Notification ② function call

Button Control Two ways of creating a control ① Create one by hand (coding) ② Create one using the dialog edit window

When clicking a button Windows sends Notification Message Message Handler for the notification Add message handler MACRO in massage map Implement the message handler function Controls (Child Window) Parent Window Notification

When changing state of CButton Call member functions of CButton Change(Set) the current state Acquire(Get) the current state Controls (Child Window) Parent Window function call

Member functions of CButton Change the state of the check box Check the state of the check box m_button.SetCheck(BST_CHECKED); m_button.SetCheck(BST_UNCHECKED); if ( m_button.GetCheck() == BST_CHECKED ) AfxMessageBox(_T(“Button is checked”));

Button Control Two ways of creating a control ① Create one by hand (coding) ② Create one using the dialog edit window

Dialog Edit Window Resource View -> Edit “Dialog” Control variables Creating and designing controls using toolbox Control variables Each control can be connected with a control variable. Call the member functions of the control variable to change/get the state of the control

Coding Practice Make a new project of Dialog Based Application Design the dialog using Dialog Edit Window and tool box

Adding Event Message Handler Use Properties window to add message handlers

Adding Event Message Handler Alternative way In dialog edit window, mouse right button click on a control  Add Event Handler

Creating control variables mouse right button click on a control  Add variables

Creating control variables Added things: // In Header file class CTestDlg::public CDiglog { ... CButton m_button; } // In Source file void CTestDlg::DoDataExchange(CDataExchange* pDX) CFormView::DoDataExchange(pDX); //{{AFX_DATA_MAP(CExButtonView) DDX_Control(pDX, IDC_BUTTON1, m_button); //}}AFX_DATA_MAP

Coding Practice Creating the following program using Dialog based application template When pushing the button, show the information

More Controls

Edit Control (1/6) Edit Control Line option:

Edit Control (1/6) Properties

Edit Control (2/6) Edit Control Style Style Description ES_LEFT Left-aligns text in the control. ES_CENTER Centers text in the control. ES_RIGHT Right-aligns text in the control. ES_AUTOHSCROLL Permits the edit control to scroll horizontally without a horizontal scroll bar. To add a horizontal scroll bar, include the style WS_HSCROLL. ES_AUTOVSCROLL Permits the edit control to scroll vertically without a vertical scroll bar. To add a vertical scroll bar, include the style WS_VSCROLL. ES_MULTILINE Creates a multiline edit control. ES_LOWERCASE Displays all characters in lowercase. ES_UPPERCASE Displays all characters in uppercase. ES_PASSWORD Displays asterisks instead of typed characters. ES_READONLY Creates an edit control whose text can't be edited. ES_NOHIDESEL Prevents the edit control from hiding the selection when the control loses the input focus. ES_OEMCONVERT Performs an ANSI-to-OEM-to-ANSI conversion on all characters typed into the control so that the application won't get unexpected results if it performs an ANSI-to-OEM conversion of its own. Obsolete. ES_WANTRETURN Programs the Enter key to insert line breaks instead of invoking the default push button for multiline edit controls used in dialog boxes.

Edit Control (4/6) Edit Control Notification Messages Notification Sent When Message-Map Macro EN_UPDATE The control's text is about to change. ON_EN_UPDATE EN_CHANGE The control's text has changed. ON_EN_CHANGE EN_KILLFOCUS The edit control loses the input focus. ON_EN_KILLFOCUS EN_SETFOCUS The edit control receives the input focus. ON_EN_SETFOCUS EN_HSCROLL The edit control is scrolled horizontally using a scroll bar. ON_EN_HSCROLL EN_VSCROLL The edit control is scrolled vertically using a scroll bar. ON_EN_VSCROLL EN_MAXTEXT A character can't be entered because the edit control already contains the number of characters specified with CEdit::LimitText or CEdit::SetLimitText. ON_EN_MAXTEXT EN_ERRSPACE An operation fails because of insufficient memory. ON_EN_ERRSPACE

Coding Practice Adding Edit Control to the dialog application

How to change the state of CEdit Call member functions of CEdit Change(Set) the current state Acquire(Get) the current state To ways of connecting a control variable with the CEdit Control By hand (implement in the DoDataExchange function) An automatic way (add variables  control variable) Controls (Child Window) Parent Window function call

How to change the state of CEdit Two ways to connect a control variable with the CEdit Control By hand (implement in the DoDataExchange function) An automatic way (add variables  control variable)

Edit Control (5/6) Inserting and Retrieving Text Set maximum number of character Clear, Cut, Copy, Paste and Undo m_edit.SetWindowText(_T("초기값입니다.")); CString str; m_edit.GetWindowText(str); m_edit.SetLimitText(10); m_edit.Clear(); m_edit.Cut(); m_edit.Copy(); m_edit.Paste(); m_edit.Undo();

Edit Control (6/6) Select text for editing Before ① After ① After ② ① m_edit.SelSel(5, 7); ② m_edit.ReplaceSel("ABC");

Scroll bar control (1/3) Scroll bar codes (interfaces)

CScrollBar Class(2/3) Member functions Member functions meaning SetScrollRange() Set the min and max range of the scroll bar SetScrollPos() Set the thumb position GetScrollPos() Get the thumb position

Scroll bar notification(3/3) Messages: Add message MACRO in MessageMap Scroll Bars have no ID. Event Message Handler WM_HSCROLL/ WM_VSCROLL ON_WM_HSCROLL() or ON_WM_VSCROLL() void OnHScroll (UINT nSBCode, UINT nPos, CScrollBar* pScrollBar); void OnVScroll (UINT nSBCode, UINT nPos, CScrollBar* pScrollBar);

Scroll bar message handler (4/3) WM_HSCROLL/WM_VSCROLL 메시지 핸들러 nSBCode Scroll bar code (types of event) nPos Position of the thumb Only use when nSBCode is SB_THUMBPOSITION or SB_THUMBTRACK pScrollBar Pointer to the scroll bar void OnHScroll (UINT nSBCode, UINT nPos, CScrollBar* pScrollBar); void OnVScroll (UINT nSBCode, UINT nPos, CScrollBar* pScrollBar);

Coding Practice Add a edit control and scroll bar control Set the range of the scroll bar to (0, 100) Show the position value of the thumb in the edit control