Lecture 5: Introducing Dialog Boxes & Child Window Controls for Win 32 API

Transcription

1 Lecture 5: Introducing Dialog Boxes & Child Window Controls for Win 32 API What is Dialog Box? How to make your project to have a Dialog Box Modal Dialog Modeless Dialog WM_INITDIALOG Child Window Controls Button, check box, etc.. Static & dynamic Child Window Controls Message Handlers Some useful API, structures 1

2 What is a Dialog Box? 1. Requesters 2. Notifications Combination of both 3. Modifiers 2

3 Modal vs. Modeless Dialog Boxes Modal Dialog box: demands a response from the user before the program will continue. If it is active, user must close it first before focus input to another part of the application. File/Print Modeless Dialog box: Opposite from above. It does not need to be closed.. Edit/Find 3

4 How to make yr project to have a dialog box Design an dialog by using Visual studio Decide it if a modal or a modeless dialog box Activating a Dialog box [แสดงไดอะล อก] Modal Dlg: DialogBox() Modeless Dlg: CreateDialog(), ShowWindow() Receiving Dialog Box Messages[ฟ งก ช นร บ action ของย สเซอร กระ ท าไปบน dialog ] DialogProc() Deactivating a Dialog box [ป ดไดอะล อก] Modal Dlg :EndDialog() Modeless Dlg: DestroyWindow() Run Ex1 4

5 Designing a Dialog box using Microsoft Visual C++.Net Developer Studio Create an empty project of Win 32 5 steps for creating a main window WinMain(), WindowProc() Project Add resource Press new button เป ด ex1.sln 5

6 Designing a Dialog box using Microsoft Visual C++.Net Developer Studio ไดอะล อกม ID :IDD_MODALDLG ป ม CANCEL ม ID:IDCANCEL 6

7 Example for a Modal Dialog สมม ต ได ออกแบบว า เม อย สเซอร กดเมน Modal_Dialog แล วไดอะล อกแบบ Modal จะ แสดงออกมาบนว นโดว หล ก ID ของเมน :IDM_MODALDLG เม อกดป ม cancel แล วไดอะล อกด งกล าวจะถ กป ดไป Demo:Ex1_ModalDlg 7

8 Response for selecting a menu LRESULT CALLBACK WindowProc(HWND hwnd, UINT message, WPARAM wparam, LPARAM lparam) int wmid, wmevent; int response; switch (message) case WM_COMMAND: wmid = LOWORD(wParam); //ขณะน ค อ ID ของแต ละเมน // Parse the menu selections: switch (wmid) case IDM_MODALDLG: //ID ของเมน ท จะเร ยก dialog box //implement codes ส าหร บเร ยก modal dialog ออกมาแสดง break;... 8

9 Creating & Using Modal Dialog Box Activating a Dialog box INT_PTR DialogBox( HINSTANCE hinstance, // handle to application instance LPCTSTR lptemplate, // identifies dialog box template HWND hwndparent, // handle to owner window DLGPROC lpdialogfunc // pointer to dialog box procedure ); Receiving Dialog Box Messages INT_PTR CALLBACK DialogProc( HWND hdlg, // handle to dialog box UINT msg, // message WPARAM wparam, // first message parameter LPARAM lparam); // second message parameter DialogProc ใช ช ออะไรก ได 9

10 Example: Activating a dialog box LRESULT CALLBACK WindowProc(HWND hwnd, UINT message, WPARAM wparam, LPARAM lparam) int wmid, wmevent; int response; switch (message) case WM_COMMAND: Activating wmid = LOWORD(wParam); //ขณะน ค อ ID ของแต ละเมน // Parse the menu selections: switch (wmid) case IDM_MODALDLG: //ID ของเมน ท จะเร ยก dialog box DialogBox(hInst, (LPCTSTR)IDD_MODALDLG, hwnd, (DLGPROC)ModalDlg); break; hinst :ต องเซ ต global variable 1 ต ว (HINSTANCE) ให ม ค าเท าก บ 1 st parameter of WinMain 10

11 INT_PTR CALLBACK ModalDlg(HWND hdlg, UINT message, WPARAM wparam, LPARAM lparam) switch (message) Receiving case WM_INITDIALOG: return TRUE; case WM_COMMAND: switch (LOWORD(wParam)) case ID_CANCEL: EndDialog(hDlg, 0); return TRUE; break; return FALSE; Deactivating a Dialog box BOOL EndDialog( ( HWND hdlg, // handle to dialog box int nresult // value to return ); Deactivating 11

12 Example for a Modeless Dialog สมม ต ได ออกแบบว า เม อย สเซอร กดเมน Modeless_Dialog แล ว เมน ม ID:IDM_MODELESSDLG ไดอะล อกแบบ Modeless จะแสดงออกมาบนว นโดว หล ก เม อกดป ม cancel แล วไดอะล อกด งกล าวจะถ กป ดไป Demo:Ex1_ModelessDlg 12

13 Designing a Dialog box using Microsoft Visual C++.Net Developer Studio ไดอะล อกม ID :IDD_MODELESSDLG ป ม CANCEL ม ID:IDCANCEL 13

14 Response for selecting a menu LRESULT CALLBACK WindowProc(HWND hwnd, UINT message, WPARAM wparam, LPARAM lparam) int wmid, wmevent; int response; switch (message) case WM_COMMAND: wmid = LOWORD(wParam); //ขณะน ค อ ID ของแต ละเมน // Parse the menu selections: switch (wmid) case IDM_MODALDLG: //ID ของเมน ท จะเร ยก dialog box... break; case IDM_MODELESSDLG: //ID ของเมน ท จะเร ยก dialog box //implement codes ส าหร บเร ยก modeless dialog ออกมาแสดง break;... 14

15 Creating & Using Modeless Dialog Box Activating a Dialog box Create the dialog box using CreateDialog() rather than DialogBox(). To show modeless dialog need to implement ShowWindow() HWND CreateDialog( HINSTANCE hinstance, // handle to application instance LPCTSTR lptemplate, // identifies dialog box template HWND hwndparent, // handle to owner window DLGPROC lpdialogfunc // pointer to dialog box procedure ); BOOL ShowWindow(HWND hwnd, int ncmdshow); Receiving Dialog Box Messages INT_PTR CALLBACK DialogProc( HWND hdlg, // handle to dialog box UINT msg, // message WPARAM wparam, // first message parameter LPARAM lparam); // second message parameter 15

16 Creating a Modeless Dialog Box LRESULT CALLBACK WindowProc(HWND hwnd, UINT message, WPARAM wparam, LPARAM lparam) switch (LOWORD(wParam))... case IDM_MODELESSDLG://ID ของเมน ท จะเร ยก modeless dialog hdlg = CreateDialog(hInst, (LPCTSTR)IDD_MODELESSDLG, hwnd, (DLGPROC)ModelessDlg); ShowWindow(hDlg, SW_SHOW); break; HWND hdlg; เป น Global variable 16

17 INT_PTR CALLBACK ModelessDlg(HWND hdlg, UINT message, WPARAM wparam, LPARAM lparam) switch (message) Receiving case WM_INITDIALOG: return TRUE; case WM_COMMAND: switch (LOWORD(wParam)) Deactivating case IDCANCEL: DestroyWindow(hDlg hdlg);// Receiving Dialog Box Messages break; return FALSE; return TRUE; Deactivating a Dialog box Close the dialog box using DestroyWindow() instead of EndDialog(). 17

18 Creating & Using Modeless Dialog Box Must add the following function to the message loop in WinMain() function BOOL IsDialogMessage( HWND hdlg, // handle of dialog box LPMSG lpmsg // address of structure with message ); HWND hdlg; // ต องเป น Global variable while (GetMessage(&msg, NULL, 0, 0) > 0) if (!IsDialogMessage(hDlg, &msg)) TranslateMessage(&msg); DispatchMessage(&msg); 18

19 WM_INITDIALOG INT_PTR CALLBACK switch (message) ModelessDlg(HWND hdlg, UINT message, WPARAM wparam, LPARAM lparam) case WM_INITDIALOG: statements; return TRUE; case WM_COMMAND: switch (LOWORD(wParam)) case IDCANCEL: DestroyWindow(hDlg); return TRUE; break; return FALSE; CreateDialog(), DialogBox() generate a WM_INITDIALOG ไว เซ ตค าเร มต นต าง ๆ ของไดอะล อก เช นเซ ต items ลงใน listbox 19

20 Child Window Controls Button, Check Box, Edit Control, Combo Box, List Box, Group Box, Radio Box, static text Slider Control 20

21 Classic Child Window Controls Controls both generate msg (when accessed by the user) and receive msg (from yr app) Static text Primarily to display text Can also display icon images Often used as labels for other controls Button Clicked by user to indicate desired actions or choices made Lots of different styles pushbutton, check box, radio button Typically notify parent window when user chooses the button Edit To enter/view/edit/delete text Single or multi-line control Lots of word processing capability Also Clear/Copy/Cut/Paste/Undo capability 21

22 Classic Child Window Controls(cont.) Scroll Bar Control attached to edge of a parent window Allows user to "scroll" the information in a parent window's client area by moving scroll bar thumb Stand-alone child window control Allows user to enter/change a value by moving scroll bar "thumb List Box Contains lists of items that can be selected Entire list is shown User selects items Selected item is highlighted Combo Box Edit box combined with a list box User selects item from list & item is copied to edit box One type allows user to type into edit box If text matches item in list, it is highlighted & scrolled into view Another type doesn t allow user to type in edit box 22

23 Example Class of Child Window Controls for Win 32 API TYPE WINDOW CLASS Static Text STATIC Button BUTTON Edit Control EDIT List Box LISTBOX Combo Box COMBOBOX Scroll Bar SCROLLBAR Child window controls have been divided into two types: Predefined data (static data) Dynamic data (run) 23

24 แบบท 1 : predefined data (static data) using visual studio Control แต ละต วก จะม ID เป นของต วเอง ซ งจะถ ก generate อ ตโนม ต และสามารถแก ไขได รวมท งสามารถเซ ต property ผ านหน าต าง Properties ได เลย เช นเซ ต caption ของ button เป นต น 24

25 WM_INITDIALOG INT_PTR CALLBACK switch (message) SimpleDlg(HWND hdlg, UINT message, WPARAM wparam, LPARAM lparam) case WM_INITDIALOG: SendDlgItemMessage(hDlg, IDC_LIST1, LB_ADDSTRING, 0, (LPARAM) Lemon ); SendDlgItemMessage(hDlg, IDC_LIST1, LB_ADDSTRING, 0, (LPARAM) Grape ); SendDlgItemMessage(hDlg, IDC_LIST1, LB_ADDSTRING, 0, (LPARAM) Apple ); SendDlgItemMessage(hDlg, IDC_LIST1, LB_ADDSTRING, 0, (LPARAM) Orange ); return TRUE; case WM_COMMAND: switch (LOWORD(wParam)) case IDCANCEL: EndDialog(hDlg,0); return TRUE; break; return FALSE; CreateDialog(), DialogBox() generate a WM_INITDIALOG ไว เซ ตค าเร มต นต างของไดอะล อกเช น เซ ต items ลงใน listbox Run: Ex1_AddItemtoListbox 25

26 แบบท 2 : dynamic data Creating Child Window Controls CreateWindow() --For any kind of window, including a control :HWND ShowWindow() HWND CreateWindow( LPCTSTR lpclassname, // pointer to registered class name LPCTSTR lpwindowname, // pointer to window name DWORD dwstyle, // window style int x, // horizontal position of window int y, // vertical position of window int nwidth, // window width int nheight, // window height HWND hwndparent, // handle to parent or owner window HMENU hmenu, // handle to menu or child-window identifier HANDLE hinstance, // handle to application instance LPVOID lpparam // pointer to window-creation data ); BOOL ShowWindow( HWND hwnd, // handle to window int ncmdshow // show state of window ); 11 parameters 26

27 Parameters: 1. Predefined control class names: "STATIC", "BUTTON", EDIT, LISTBOX, COMBOBOX, SCROLLBAR, etc. 2. Name of the window For BUTTON, EDIT, STATIC classes: text in center of control For COMBOBOX, LISTBOX, SCROLLBAR: ignored (use "") 3. Window style WS_, SS_, BS_, ES_, LBS_, CBS_, SBS_ (see CreateWindow help) Several styles can be combined with the bitwise or operator ( ) All controls should include WS_CHILD style Parameters 4-7: X,Y position (Relative to the upper left corner of parent window client area) Width & Height 8. Handle to the parent window 9. Handle to menu Controls don t have menus So hmenu parameter used to hold control s integer ID must define in resource.h file ID value passed with WM_COMMAND message generated when user interacts with the control 10. Handle to instance of program creating control: 1 st parameter of WinMain() 11. Pointer to window creation data : normally NULL 27

28 Example: Creating a Push button dynamically // Global Variables: HINSTANCE hinst;// current instance HWND dynamicbutton; // dynamic create button //ใน File resource.h #define IDC_DYNAMICBUTTON INT_PTR CALLBACK SimpleDlg(HWND hdlg, UINT message, WPARAM wparam, LPARAM lparam) long i; char str[80]; switch (message) case WM_COMMAND: switch (LOWORD(wParam)) case IDC_CREATEBUTTON: dynamicbutton = CreateWindow("BUTTON", "Push Me", WS_CHILD BS_PUSHBUTTON, 300,200,130,60, hdlg, (HMENU)IDC_DYNAMICBUTTON, hinst, NULL); ShowWindow(dynamicButton, SW_SHOWNORMAL); return TRUE; case IDC_DYNAMICBUTTON: MessageBox(hDlg, "Press Dynamic Button", "Dynamic", MB_OK); return TRUE;... 28

29 Child Window Controls Message Handlers User interacts with the control Detect each a child window control under WM_COMMAND ยกเว น scroll bar control LOWORD(wParam) = Control ID Put Control message handlers in same switch/case statement INT_PTR CALLBACK SimpleDlg(HWND hdlg, UINT message, WPARAM wparam, LPARAM lparam) switch (message) case WM_COMMAND: switch (LOWORD(wParam)) case IDCANCEL: EndDialog(hDlg,0); return TRUE; break; return FALSE; 29

30 Child Window Controls Message Handlers HIWORD(wParam) = notification code identifies what the user action was Ex. If (HIWORD(wParam) ==LBN_DBCLK) notification message when the user double-clicks a string in a list box INT_PTR CALLBACK SimpleDlg(HWND hdlg, UINT message, WPARAM wparam, LPARAM lparam) switch (message) case WM_COMMAND: switch (LOWORD(wParam)) case IDC_LIST1: // process a list box LBN_DBLCLK if (HIWORD(wParam)== LBN_DBLCLK) i = SendDlgItemMessage(hDlg, IDC_LIST1, LB_GETCURSEL, 0, 0); sprintf(str, "Index in list is: %d",i); SetDlgItemText(hDlg,IDC_EDIT1,str); return TRUE; case IDCANCEL: EndDialog(hDlg,0); return TRUE; break; return FALSE; 30

31 Child Window Controls Message Handlers (HWND)lParam = handle of control: HWND Scroll Bars are a bit different : WM_VSCROLL, WM_HSCROLL INT_PTR CALLBACK SimpleDlg(HWND hdlg, UINT message, WPARAM wparam, LPARAM lparam) switch (message) case WM_COMMAND: switch (LOWORD(wParam)) case IDC_DYNAMICBUTTON: SetWindowText((HWND)lParam, "CHANGE"); return TRUE; case IDCANCEL: EndDialog(hDlg,0); return TRUE; break; return FALSE; Run:Ex1_SetWindowText 31

32 Sending a Message to a List Box Unlike a push button, it can receive several different msgs : LRESULT SendDlgItemMessage( HWND hdlg, // handle of dialog box int niddlgitem, // identifier of control UINT Msg, // message to send WPARAM wp, // first message parameter LPARAM lp // second message parameter ); Initializing the list box when the dialog box is first displayed LB_ADDSTRING : Add a string (selection) to the list box case WM_INITDIALOG: SendDlgItemMessage(hDlg, IDC_LIST1, LB_ADDSTRING, 0, (LPARAM)"Lemon"); Response to the user selecting an item from the list LB_GETCURSEL : Requests the index of the selected item LRESULT CALLBACK DialogProc(HWND hwnd, UINT message, WPARAM wparam, LPARAM lparam)... case IDC_LIST1: if (HIWORD(wParam) == LBN_DBLCLK) i = SendDlgItemMessage(hDlg, IDC_LIST1, LB_GETCURSEL, 0,0); // get index if (i!= LB_ERR) do something

33 Examples : List Box Messages INT_PTR CALLBACK MyDialog1(HWND hdlg, UINT message, WPARAM wparam, LPARAM lparam)... LBN_DBLCLK LBN_ERRSPACE LBN_KILLFOCUS LBN_SELCANCEL LBN_SELCHANGE LBN_SETFOCUS Notification Messages If (HIWORD(wParam)==notification code))... Action ท เก ดจากการกระท าของย สเซอร ต อ listbox LB_ADDFILE LB_ADDSTRING LB_DELETESTRING LB_GETCURSEL LB_DIR LB_SETCARETINDEX LB_SETCOLUMNWIDTH LB_SETCOUNT LB_SETCURSEL LB_SETHORIZONTALEXTENT SendDlgItemMessage(p1,p2,UINT msg,p4,p5) If (HIWORD(wParam)==notification code)) SendDlgItemMessage(...)... Etc.. LOWORD(wParam) = Control ID 33

34 Examples: Edit Control or edit box Messages EN_CHANGE EN_KILLFOCUS EN_MAXTEXT EN_SETFOCUS Notification Messages if (HIWORD(wParam)==notification code)... Action ท เก ดจากการกระท าของย สเซอร ต อ Edit control EM_CHARFROMPOS EM_EMPTYUNDOBUFFER EM_FMTLINES EM_LINELENGTH EM_GETFIRSTVISIBLELINE EM_GETHANDLE EM_GETIMESTATUS EM_SETLIMITTEXT EM_SETMARGINS EM_SETMODIFY EM_SETPASSWORDCHAR EM_SETREADONLY SendDlgItemMessage(p1,p2,UINT msg,p4,p5) case IDC_EDIT1: if (HIWORD(wParam) == EN_CHANGE) SendDlgItemMessage(...) 34

35 Example codes: EN_MAXTEXT case WM_INITDIALOG: SendDlgItemMessage(hDlg, IDC_EDIT1, EM_SETLIMITTEXT, 5,0); break; case WM_COMMAND: int mevent = HIWORD(wParam); switch (LOWORD(wParam)) case IDC_EDIT1: if (HIWORD(wParam) ==EN_MAXTEXT) MessageBox(hDlg, "Only 5 characters", "MaxCharacter", MB_OK); return TRUE; 35

36 Example: Notification Messages from Button Message Description BN_CLICKED The user clicked a button. BN_DISABLE A button is disabled. BN_PUSHED The user pushed a button. BN_KILLFOCUS The button lost the keyboard focus. BN_PAINT The button should be painted. BN_SETFOCUS The button gained the keyboard focus. BN_UNPUSHED The button is no longer pushed HIWORD(wParam) identifies what the user action was if (HIWORD(wParam)==BN_KILLFOCUS) 36

37 Check Box & Radio Button BM_GETCHECK p4,p5 = 0 SendDlgItemMessage(p1,p2,UINT msg,p4,p5) BM_SETCHECK p4 = BST_CHECKED or BST_UNCHECKED p5=0 Example: case WM_INITDIALOG: SendDlgItemMessage(hDlg, IDC_CHECK1, BM_SETCHECK,BST_CHECKED,0); case IDC_CHANGEBUTTON: if (BST_UNCHECKED == SendDlgItemMessage(hDlg, IDC_CHECK1, BM_GETCHECK,0,0)) SendDlgItemMessage(hDlg, IDC_CHECK1, BM_SETCHECK,BST_CHECKED,0); 37

38 Some Useful APIs for Controls The GetDlgItem function retrieves the handle of a control in the specified dialog box. HWND GetDlgItem( HWND hdlg, // handle of dialog box int niddlgitem // identifier of control ); SetWindowText(HWND hwnd, LPCTSTR lpstring) The GetDlgItemText function retrieves the title or text associated with a control in a dialog box. UINT GetDlgItemText( HWND hdlg, // handle of dialog box int niddlgitem, // identifier of control LPTSTR lpstring, // address of buffer for text int nmaxcount // maximum size of string ); The GetDlgItemInt function translates the text of a specified control in a dialog box into an integer value UINT GetDlgItemInt( HWND hdlg, // handle to dialog box int niddlgitem, // control identifier BOOL *lptranslated, // points to variable to receive success/failure BOOL bsigned // specifies whether value is signed or unsigned ); 38

39 Example: an Edit box int num; case IDC_BUTTON3: num = GetDlgItemInt(hDlg, IDC_EDIT3, NULL, TRUE); sprintf(str,"%d",num); MessageBox(hDlg, str, "Edit Box Contains", MB_OK); char str[80]; case IDOK : /* edit box OK button selected*/ /* display contents of the edit box*/ GetDlgItemText(hDlg, IDC_EDIT1, str, 80); MessageBox(hDlg, str, Edit Box Contains, MB_OK); 39

40 Some Useful APIs for Controls The SetDlgItemInt function sets the text of a control in a dialog box to the string representation of a specified integer value. BOOL SetDlgItemInt( HWND hdlg, // handle of dialog box int niddlgitem, // identifier of control UINT uvalue, // value to set BOOL bsigned // signed or unsigned indicator ); The SetDlgItemText function sets the title or text of a control in a dialog box. BOOL SetDlgItemText( HWND hdlg, // handle of dialog box int niddlgitem, // identifier of control LPCTSTR lpstring // text to set ); 40

41 Scroll Bars The first is an integral part of a normal window or dialog box Call a standard scroll bar CreateWindow( szwindowclass,... WS_OVERLAPPEDWINDOW WS_VSCROLL WS_HSCROLL,...) The second exists separately as a control Call a scroll bar control Drag from Tool box during designing a dialog box 41

42 Scroll Bars LPRESULT CALLBACK WindowProc(HWND hwnd, UINT message, WPARAM wparam, LPARAM lparam)... Activating the Scroll Bars CreateWindow() : for standard scroll bar Window style: WS_VSCROLL WS_HSCROLL Scroll bar control: drag from tool box Receiving Scroll Bar Messages WM_VSCROLL or WM_HSCROLL Unlike other controls generate WM_COMMNAD LOWORD(wParam) : specify what type of scroll bar action SB_LINEUP, SB_LINEDOWN, SB_PAGEUP, SB_PAGEDOWN, etc lparam Standard scroll bars : lparam = 0 Scroll bar control : lparam contains its handle :HWND 42

43 Example codes for Scroll bar INT_PTR CALLBACK WndProc(HWND hwnd, UINT message, WPARAM wparam, LPARAM lparam) switch (message) case WM_VSCROLL VSCROLL: switch(loword(wparam)) case SB_LINEDOWN: break; case SB_LINEUP: break; case SB_THUMBPOSITION: break; case SB_THUMBTRACK: break; case SB_PAGEDOWN: break; case SB_PAGEUP: break; 43

44 If (HWND)lParam== GetDlgItem(hDlg, IDC_SCROLLBAR1)) 44

45 Useful structures OPENFILENAME CHOOSEFONT เป ด MSDN CHOOSECOLOR 45