BOXES DIALOG AND CONTROLS
Dialog Boxes
A dialog box is a temporary window that Windows creates for special-purpose input and then destroys immediately after use. An application typically uses a dialog box to prompt the user for additional information about a current command selection.
Types of Dialog Boxes
A modeless dialog box allows the user to supply information and return to the previous task without canceling or removing the dialog box. A modal dialog box requires the user to respond to a request or supply information before the application can continue. We will create a MODAL dialog box.
What Are They For?
A Dialog Box is simply a window that holds controls provided to allow the user to communicate with the program. CONTROLS are actually what communicates with the program - Not the Dialog Box.
Controls
Text Box (where user can type text) Drop Down List Box Combo Box (both text and drop down list) Check Boxes Radio Buttons (grouped-only one selected at a time) Scroll Bars Buttons - OK, CANCEL, Buttons on Button Bar Menu Items Any item intended to receive info from the user to be sent back to the program.
Creating a Dialog Box
Select the Resource Workshop and/or open the .rc file associated with your project. Select Resource, New, then select Dialog. Select the type of Dialog Box you want to create. A Dialog Box will appear. You will use drag-ndrop to assign controls to it.
Adding Controls to a Dialog Box
Use the Tools bar to select and drop controls such as Check Boxes or Buttons onto the Dialog Box. Double Click each control to make changes to its style, name and id. Right Click the background of the Dialog Box and select Style to change the title that appears on the Dialog Box or Test to test the Dialog Box. Resource, Edit as text to change the name used by the program to access the dialog box. Save the Resource Project after making any changes or additions to your resources.
Processing Box Dialog Messages
Dialog Box controls receive messages from the mouse or keyboard and send them to your program. You must process these messages in your code. The first step is to write a new function to process dialog box messages. It will have a switch statement that handles the IDs of the controls on your dialog box very similar to MainWndProc.
Write a Simple Dialog Procedure
BOOL CALLBACK Pizza ( HWND hDlg, UINT message, WPARAM wParam, LPARAM lParam ) { switch ( message ) { case WM_INITDIALOG: /* message: initialize dialog box */ return ( TRUE ); case WM_COMMAND: /* message: received a command */ switch (wParam) { case IDOK: MessageBox( hWnd, "You clicked OK", "Response", MB_OK); break; case IDCANCEL: EndDialog ( hDlg, TRUE ); /* Exits the dialog box */ return ( TRUE ); } } return ( FALSE ); } /* Didn't process a message */
In MainWndProc
1 Use MakeProcInstance to get a handle to (or memory for) your dialog box procedure. 2 Use the DialogBox function to load the dialog box resource and show the box on the screen (the DialogBox function creates a MODAL dialog box). 3 Use FreeProcInstance to clean up ...