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May 98 - Getting Started

Volume Number: 14 (1998)
Issue Number: 5
Column Tag: Getting Started

Handling Modeless Dialogs

by Dave Mark

Looking deeper into the Dialog Manager

Over the last few columns, we've explored the mysteries of the Dialog Manager via a program called Dialogger. As promised, the next few columns will go deeper into the Dialog Manager, presenting a program called Modeless. Modeless implements a modeless dialog, a dialog that looks and acts like a regular window, but retains the benefits of being managed by the Dialog Manager.

Modeless dialogs require a change in the usual modal programming strategy. Modal dialog handling code is usually pretty self-contained. Modeless code tends to be larger and more spread out, as you'll see when we get to the code.

Creating the Modeless Resources

Most of the resources we'll need for this month's column can be copied from last month's resource file, Dialogger.rsrc. Start by creating a new folder in your Development folder named Modeless. Next, duplicate the file Dialogger.rsrc and drag the copy into the Modeless folder. Change the name of this file to Modeless.rsrc.

Next, launch ResEdit by double-clicking the file Modeless.rsrc. The Modeless.rsrc window should look similar to the one shown in Figure 1.

Figure 1. Modeless.n.rsrc, before surgery.

Your first mission is to edit the ALRT, replacing any references to Dialogger with the appropriate reference to Modeless. Double-click on the ALRT icon. When the ALRT-picker window appears, double-click the only ALRT listed, the one with a resource ID of 129. When the ALRT editor appears, double-click the ALRT window so the DITL editor appears. Finally, double-click the static text item and, when the static text editor appears, make your changes. Mine are shown in Figure 2.

Figure 2. A new version of the About... ALRT.

When you're happy with your About message, close all the windows until you are back at the main window. Next, you'll change the About Dialogger item in the Apple menu to read About Modeless.

Double-click the MENU icon to bring up the MENU picker window. Next, double-click the Apple MENU, bringing up the MENU editing window. Click the About Dialogge. item and change it so it says About Modeless, as shown in Figure 3.

Figure 3. A new version of the MENU resource.

Close the Apple MENU editing window, then double-click the File menu, bringing up the File MENU editing window. Click the Settings item and then click in the Cmd-key: field. Type the letter S in the Cmd-key: field. This ties the command-key equivalent S to the Settings item in the File menu. My File MENU editing window is shown in Figure 4.

Figure 4. A new version of the File MENU resource.

Once you are done, close all the windows leaving just the main window open. Our final chore is to edit the DLOG and DITL resources that made up Dialogger's modal dialog, changing them to reflect the look of a modeless dialog.

Double-click the DLOG icon to bring up the DLOG-picker window. Next, double-click the only DLOG listed, the one with the resource id of 128. The Settings DLOG editing window should appear. First, click the Initially visible check box, making sure it is unchecked.

Next, click the second window icon from the left, at the top of the editing window. The DLOG window should change to reflect your new selection. Modeless dialogs don't have the traditional double-border of their modal cousins. Instead, they look like regular windows. In this case, we want to give our dialog window a close box, so make sure the Close box check box is checked.

We also want to give our dialog window a title. Select Set 'DLOG' Characteristics from the DLOG menu. When the 'DLOG' Characteristics dialog appears, type the text Fred Settings in the Window title: field and click OK. Your new title should be reflected in the DLOG editing window. Figure 5 shows my DLOG editing window at this point in the process.

Figure 5. The DLOG editing window, at the half-way point.

Next, we'll edit the DITL associated with this DLOG. Double click the DLOG window (within the editing window) so the DITL editing window appears. You are now going to delete all the items in the DITL except the Pick one: static text item and the three radio buttons.

Click the OK button and press the delete key. Click the Cancel button and press the delete key. Click the Show preview check box and press the delete key. Finally, click the user item (the grey rectangle) and press delete.

Next, you'll change the positioning of the remaining four items. Double-click the Pick one: static text item and change its coordinates to the ones shown in Figure 6. Close the window when you are done.

Figure 6. New coordinates for the Pick one: static text item.

Double-click the Afghan radio button and change its coordinates to the ones shown in Figure 7. Close the window when you are done.

Figure 7. New coordinates for the Afghan radio button.

Double-click the Elephant radio button and change its coordinates to the ones shown in Figure 8. Close the window when you are done.

Figure 8. New coordinates for the Elephant radio button.

Double-click the Squirrel radio button and change its coordinates to the ones shown in Figure 9. Close the window when you are done.

Figure 9. New coordinates for the Squirrel radio button.

Now we're almost done. Close the DITL editing window, leaving you back in the DLOG editing window. The last thing left to do is to resize the DLOG to reflect its slimmed down and rearranged DITL. Change the Bottom: to 123 and the Right: to 234. The final version of our DLOG is shown in Figure 10.

Figure 10. The final version of our DLOG.

Quit ResEdit, being sure to save your changes. Now we're ready to enter our source code.

Creating the Modeless Project

Launch CodeWarrior and create a new project based on the MacOS:C/C++:Basic Toolbox 68k stationary. Turn off the Create Folder check box. Name the project Modeless.mcp and place it in your Modeless folder. Remove SillyBalls.c and SillyBalls.rsrc from the project; we will not be using these files. From the Finder, drag and drop your Modeless.rsrc file into the project window. You also can remove the ANSI Libraries group from the project, because we won't need them, either.

Select New from the File menu to create a new window. Save it with the name Dialogger.c in your Modeless folder. Select Add Window from the Project menu to add Dialogger.c to the project. Your project window should look something like Figure 11.

Figure 11. Dialogger project window.

Rather than print the code here twice, we'll go straight to the walk-through. You can type in the code as we discuss it below and you will end up with the complete program, or you can save your fingers some effort and get the complete project from MacTech's ftp site ftp://ftp.mactech.com/src/mactech/volume14_1998/14.05.sit.

Walking Through the Source Code

Much of the Modeless source code will look familiar to you from earlier programs. As usual, Modeless starts off #including necessary header files, then it begins a series of #defines. The first three define the base resource ID, and the resource IDs for the ALRT and DLOG resources.

#include <Controls.h>
#include <Dialogs.h>
#include <Menus.h>
#include <Quickdraw.h>
#include <Sound.h>

#define kBaseResID        128
#define kAboutALRTid      129
#define kDialogResID      128

kVisible, kMoveToBack, kMoveToFront, and kNoGoAway are used in the calls to NewWindow() and GetNewDialog(). kSleep, as usual, is passed to WaitNextEvent().

#define kVisible          true
#define kMoveToBack       NULL
#define kMoveToFront      (WindowPtr)-1L
#define kNoGoAway         false
#define kSleep            7L

kOn and kOff are passed to SetControlValue() to turn a radio button on and off.

#define kOn                 1
#define kOff                0

These three #defines define the item IDs for the three radio buttons that appear in the modeless dialog.

#define iAfghan             1
#define iElephant           2
#define iSquirrel           3

kLeftMargin and kTopMargin determine the position of the My Pet Fred window on the screen.

#define kLeftMargin         5
#define kTopMargin         40

kFirstRadio defines the ID of the first radio button in the modeless dialog. kLastRadio defines the ID of the last radio button in the set.

#define kFirstRadio        1
#define kLastRadio         3

The remainder of the #defines represent the Modeless menus and menu items.

#define mApple             kBaseResID
#define iAbout             1

#define mFile              kBaseResID+1
#define iSettings          1
#define iQuit              3

Modeless makes use of four global variables. gDone is set to true until the program is ready to exit. gCurrentPICT contains the ID of the current My Pet Fred PICT. gSettingsDLOG is a pointer to the modeless dialog. We made this a global so we could keep the modeless dialog settings around, even if we close the dialog. gFredWindow points to the My Pet Fred window. We'll take advantage of this pointer when we delete the My Pet Fred window and create a new one.

Boolean     gDone;
short       gCurrentPICT = kBaseResID;
DialogPtr   gSettingsDLOG = NULL;
WindowPtr   gFredWindow = NULL;

As always, we created a function prototype for each of the Modeless functions.

void         ToolBoxInit( void );
PicHandle    LoadPICT( short picID );
void         CreateWindow( void );
void         MenuBarInit( void );
void         EventLoop( void );
void         DoEvent( EventRecord *eventPtr );
void         DoDialogEvent( EventRecord *eventPtr );
void         HandleMouseDown( EventRecord *eventPtr );
void         HandleMenuChoice( long menuChoice );
void         HandleAppleChoice( short item );
void         HandleFileChoice( short item );
void         DoUpdate( EventRecord *eventPtr );
void         CreateDialog( void );
void         FlipControl( ControlHandle control );
void         SwitchPICT( void );

main() starts off by initializing the Toolbox. Next, the menu bar is set up and the My Pet Fred window is created. Finally, we begin the main event loop.

/********** main **********/

void   main( void )
{
   ToolBoxInit();
   MenuBarInit();
   
   CreateWindow();
   
   EventLoop();
}

Nothing new about ToolBoxInit().

/********** ToolBoxInit **********/

void   ToolBoxInit( void )
{
   InitGraf( &qd.thePort );
   InitFonts();
   InitWindows();
   InitMenus();
   TEInit();
   InitDialogs( NULL );
   InitCursor();
}

Just like its Dialogger counterpart, LoadPICT() takes a resource ID as an input parameter, loads the specified PICT resource, then returns a handle to the PICT.

/********** LoadPICT **********/

PicHandle   LoadPICT( short picID )
{
   PicHandle   pic;
   
   pic = GetPicture( picID );

If the PICT could not be loaded for some reason, the program beeps once, then exits.

   if ( pic == NULL )
   {
      SysBeep( 10 );   /* Couldn't load the PICT resource!!! */
      ExitToShell();
   }

   return( pic );
}

CreateWindow() creates a new My Pet Fred window.

/********** CreateWindow **********/

void   CreateWindow( void )
{
   PicHandle   pic;
   Rect            r;

First, LoadPICT() is called to load the PICT specified by gCurrentPICT.

   pic = LoadPICT( gCurrentPICT );

Next, the PICT's bounding rectangle is stored in the local variable r.

   r = (**pic).picFrame;

OffsetRect() is called to normalize the Rect, keeping it the same size as the PICT, but moving its upper left corner to the position specified by kLeftMargin and kTopMargin. Basically, we're setting up the bounding rectangle for the new My Pet Fred window.

   OffsetRect( &r, kLeftMargin - r.left,
               kTopMargin - r.top );

This rectangle is passed to NewWindow(). The new window is made visible. Notice that kMoveToBack is passed instead of our normal kMoveToFront. Why? We want the window to appear behind the modeless dialog window, if the dialog is currently visible.

   gFredWindow = NewWindow( NULL, &r, "\pMy Pet Fred", 
         kVisible, noGrowDocProc, kMoveToBack, kNoGoAway, 0L );

If the window couldn't be created for some reason, beep once, then exit.

   if ( gFredWindow == NULL )
   {
      SysBeep( 10 );   /* Couldn't load the WIND resource!!! */
      ExitToShell();
   }

Finally, make the window visible (this line is unnecessary because we created the window with kVisible, but it's a good habit to get into) and make it the current port. We'll draw the current Fred by responding to an update event.

   ShowWindow( gFredWindow );
   SetPort( gFredWindow );
}

MenuBarInit() loads the MBAR resource, and makes it the current menu bar.

/********** MenuBarInit **********/

void   MenuBarInit( void )
{
   Handle            menuBar;
   MenuHandle      menu;
   
   menuBar = GetNewMBar( kBaseResID );
   SetMenuBar( menuBar );

Next, a handle to the Apple menu is retrieved and the desk accessories added to the menu.

   menu = GetMenuHandle( mApple );
   AppendReMenu( menu, 'DRVR' );

Finally, the menu bar is redrawn.

   DrawMenuBar();
}

EventLoop() looks much the same. As you'd expect, the program exits when gDone is set to true.

/********** EventLoop **********/

void   EventLoop( void )
{      
   EventRecord      event;
   
   gDone = false;
   while ( gDone == false )
   {
      if ( WaitNextEvent( everyEvent, &event, kSleep, NULL ) )
         DoEvent( &event );
   }
}

DoEvent() is slightly different than previous incarnations.

/********** DoEvent **********/

void   DoEvent( EventRecord *eventPtr )
{
   char      theChar;

The first difference lies in our call of IsDialogEvent(). IsDialogEvent() takes a pointer to an EventRecord as a parameter and returns true if the event is associated with a modeless dialog. Note that our code calls IsDialogEvent() whether or not a modeless dialog is currently open. Since we aren't that concerned with efficiency here, this is just fine. In a more complex program, you might want to check to see if any of your modeless dialogs are open before you call IsDialogEvent(). Obviously, if your program contains no modeless dialogs, you shouldn't call IsDialogEvent().

   if ( IsDialogEvent( eventPtr ) )
   {

If IsDialogEvent() returns true, the event is associated with our modeless dialog box and we'll pass it along to DoDialogEvent() for processing.

      DoDialogEvent( eventPtr );
   }

If the event is not associated with a modeless dialog, we'll process the event as we always did, using a switch statement.

   else
   {
      switch ( eventPtr->what )
      {

A mouseDown is handled by HandleMouseDown().

         case mouseDown: 
            HandleMouseDown( eventPtr );
            break;

keyDown and autoKey events are turned into characters and turned from command-key equivalences (if appropriate) into menu selections by MenuKey(). The menu selections are handled by HandleMenuChoice().

         case keyDown:
         case autoKey:
            theChar = eventPtr->message & charCodeMask;
            if ( (eventPtr->modifiers & cmdKey) != 0 ) 
               HandleMenuChoice( MenuKey( theChar ) );
            break;

updateEvts are handled by DoUpdate(). Since the update events for our modeless dialog will have been diverted to DoDialogEvent(), any updateEvts passed to DoUpdate() will be for the My Pet Fred window.

         case updateEvt:
            DoUpdate( eventPtr );
            break;
      }
   }
}

All events for the modeless dialog are passed to DoDialogEvent().

/********** DoDialogEvent **********/

void   DoDialogEvent( EventRecord *eventPtr )
{
   short         itemHit;
   short         itemType;
   Handle        itemHandle;
   Rect          itemRect;
   short         curRadioButton, i;
   char          theChar;
   Boolean       becomingActive;
   MenuHandle    menu;
   DialogPtr     dialog;

We'll start off by fetching a handle to the File menu. Why? We're going to dim the Settings item if the modeless dialog is up front. Remember, we're doing this just to demonstrate how it's done, not because it's needed.

   menu = GetMenuHandle( mFile );

Notice that we process keyDown and autoKey events in two different places. If the modeless dialog is up front, DoDialogEvent() will get all keyDowns and autoKeys. If the modeless dialog is not up front or is not open, the normal event handling mechanism will get the keyDowns and autoKeys.

   switch ( eventPtr->what )
   {
      case keyDown:
      case autoKey:
         theChar = eventPtr->message & charCodeMask;
         if ( (eventPtr->modifiers & cmdKey) != 0 ) 
            HandleMenuChoice( MenuKey( theChar ) );
         break;

If the modeless dialog window is either being activated or deactivated, DoDialogEvent() will get an activateEvt. In that case, we'll use the activeFlag to determine whether becomingActive should be set to true or false.

      case activateEvt:
         becomingActive = ( (eventPtr->modifiers & activeFlag)
                              == activeFlag );

If the modeless dialog window is becoming active, we'll use HiliteControl() to enable all the radio buttons, from kFirstRadio to kLastRadio, then we'll disable the File menu's Settings item.

         if ( becomingActive )
         {
            for ( i=kFirstRadio; i<=kLastRadio; i++ )
            {
               GetDialogItem( gSettingsDLOG, i, &itemType,
                     &itemHandle, &itemRect );
               HiliteControl( (ControlHandle)itemHandle, 0 );
            }
            DisableItem( menu, iSettings );
         }

If the modeless dialog window is being deactivated, we'll dim all the radio buttons and enable the Settings item. When the user goes to the File menu and sees that Settings is dimmed, they'll have a clue that the modeless dialog is already up front and ready to use.

         else
         {
            for ( i=kFirstRadio; i<=kLastRadio; i++ )
            {
               GetDialogItem( gSettingsDLOG, i, &itemType,
                     &itemHandle, &itemRect );
               HiliteControl( (ControlHandle)itemHandle, 255 );
            }
            EnableItem( menu, iSettings );
         }
         break;
   }

The previous chunk of code accomplished two things. First, it made sure that command-key equivalents were supported. Second, it made any user interface adjustments that were not normally handled by the Dialog Manager. We decided to dim the radio buttons when the modeless window is deactivated and dim the Settings item when the modeless window is activated. These user interface adjustments are window trimmings that we decided to add. The program would still work without them.

Next, we're going to the things that absolutely must be done. DialogSelect() is the modeless version of ModalDialog(). DialogSelect() takes the event pointer and maps it to a specific dialog and a specific item in the dialog. DialogSelect() returns true if we need to do some processing (if an item was actually hit).

   if ( DialogSelect( eventPtr, &dialog, &itemHit ) )
   {

Since our dialog was relatively simple, we know that itemHit is going to be one of iAfghan, iElephant, or iSquirrel.

      switch ( itemHit )
      {
         case iAfghan:
         case iElephant:
         case iSquirrel:

Before we process the radio button click, we'll first calculate which radio button should be currently lit.

            curRadioButton = gCurrentPICT - 
                     kBaseResID + kFirstRadio;

If the button that was clicked in is not the current radio button, we've got some work to do.

            if ( curRadioButton != itemHit )
            {

First, we'll turn off the current radio button.

               GetDialogItem( dialog, curRadioButton, &itemType,
                     &itemHandle, &itemRect );
               FlipControl( (ControlHandle)itemHandle );

Next, we'll turn on the radio button that was just clicked. Remember, always turn off a radio button before you turn on a new one.

               GetDialogItem( dialog, itemHit, &itemType,
                     &itemHandle, &itemRect );
               FlipControl( (ControlHandle)itemHandle );

Next, update curRadioButton to reflect the newly clicked radio button.

               curRadioButton = itemHit;

Next we check to see if the current PICT is still up to date.

               if ( gCurrentPICT != curRadioButton +
                     kBaseResID - kFirstRadio )
               {

If not, we'll set it to its new value, then call SwitchPICT() to update the My Pet Fred window.

                  gCurrentPICT = curRadioButton +
                        kBaseResID - kFirstRadio;
                  SwitchPICT();
               }
            }
            break;
      }
   }
}

HandleMouseDown() works much the same as always.

/********** HandleMouseDown **********/

void   HandleMouseDown( EventRecord *eventPtr )
{
   WindowPtr      window;
   short          thePart;
   long           menuChoice;
   MenuHandle     menu;

First, we call FindWindow() to find out what window the mouseDown was in and where in the window the mouseDown occurred.

   thePart = FindWindow( eventPtr->where, &window );

If the mouseDown was in the menu bar, pass the menu selection on to HandleMenuChoice(). A mouseDown in inSysWindow gets passed on to SystemClick().

   switch ( thePart )
   {
      case inMenuBar:
         menuChoice = MenuSelect( eventPtr->where );
         HandleMenuChoice( menuChoice );
         break;
      case inSysWindow : 
         SystemClick( eventPtr, window );
         break;

A mouseDown inContent causes a call to SelectWindow() to bring the clicked-in window to the front.

      case inContent:
         SelectWindow( window );
         break;

Note that this line will get executed even if the mouse click was in the modeless dialog, but only if the modeless dialog was in the back when it was clicked in. Want to prove this? Try adding this line after the call of SelectWindow() but before the break:

if ( window == gSettingsDLOG ) SysBeep( 20 );

If the mouseDown was inDrag, call DragWindow() to drag the window around on the screen.

      case inDrag : 
         DragWindow( window, eventPtr->where, 
               &qd.screenBits.bounds );
         break;

This next case is interesting. If the mouseDown was inGoAway, call TrackGoAway() to ensure that the mouse button was released inside the close box.

      case inGoAway:
         if ( TrackGoAway( window, eventPtr->where ) )

If so, verify that the click was in the modeless dialog's close box (the only window with a close box, by the way).

            if ( window == gSettingsDLOG )
            {

If so, make the modeless dialog window invisible. Why not close the window? We want to keep the dialog around so if the user brings it back up, it will have the same settings and will be in the same position, without us having to keep track of all that stuff.

               HideWindow( window );

Once the window is hidden, we'll enable the File menu's Settings item.

               menu = GetMenuHandle( mFile );
               EnableItem( menu, iSettings );
            }
         break;
   }
}

HandleMenuChoice() does what it always has, dispatching menu selections to the Apple and File menus.

/********** HandleMenuChoice **********/

void   HandleMenuChoice( long menuChoice )
{
   short      menu;
   short      item;
   
   if ( menuChoice != 0 )
   {
      menu = HiWord( menuChoice );
      item = LoWord( menuChoice );
      
      switch ( menu )
      {
         case mApple:
            HandleAppleChoice( item );
            break;
         case mFile:
            HandleFileChoice( item );
            break;
      }
      HiliteMenu( 0 );
   }
}

HandleAppleChoice() puts up an alert if the first item on the Apple menu was selected. An alert is like a dialog, but is not interactive (other than dismissing it). The alert comes up and is then dismissed, usually by a button click. Read the section on alerts in Inside Macintosh: Macintosh Toolbox Essentials. Alerts are not complicated.

/********** HandleAppleChoice **********/

void   HandleAppleChoice( short item )
{
   MenuHandle   appleMenu;
   Str255       accName;
   short        accNumber;
   
   switch ( item )
   {
      case iAbout:
         NoteAlert( kAboutALRTid, NULL );
         break;
      default:
         appleMenu = GetMenuHandle( mApple );
         GetMenuItemText( appleMenu, item, accName );
         accNumber = OpenDeskAcc( accName );
         break;
   }
}

HandleFileChoice() handles the two items in the File menu.

/********** HandleFileChoice **********/

void   HandleFileChoice( short item )
{

If Settings was selected, we first check to see if the modeless dialog was created yet. If not, we create it by calling CreateDialog().

   switch ( item )
   {
      case iSettings:
         if ( gSettingsDLOG == NULL )
            CreateDialog();

If the dialog does exist, we make it visible and bring it to the front. How does the Settings... item get dimmed, you might ask. When the dialog is brought to the front, an activateEvt gets posted. The activateEvt handling code takes care of that.

         else
         {
            ShowWindow( gSettingsDLOG );
            SelectWindow( gSettingsDLOG );
         }
         break;

As always, when Quit is selected, we set gDone to true and drop out of the program.

      case iQuit:
         gDone = true;
         break;
   }
}

Since events for the modeless dialog are handled elsewhere, the only update event this code will see is for the My Pet Fred window.

/********** DoUpdate **********/

void   DoUpdate( EventRecord *eventPtr )
{
   PicHandle   pic;
   WindowPtr   window;
   Rect            r;

We'll retrieve the WindowPtr from eventPtr->message and load the current Fred PICT using LoadPICT.

   window = (WindowPtr)eventPtr->message;
   
   pic = LoadPICT( gCurrentPICT );

Next, we make the window the current port, call BeginUpdate(), then draw the newest version of Fred and call EndUpdate().

   SetPort( window );
   
   BeginUpdate( window );
   
   r = window->portRect;
   DrawPicture( pic, &r );
   
   EndUpdate( window );
}

Just as we'd do with a modal dialog, we load the modeless DLOG resource by calling GetNewDialog().

/********** CreateDialog **********/

void   CreateDialog( void )
{
   short      itemType;
   Handle      itemHandle;
   Rect         itemRect;
   short      curRadioButton;

   gSettingsDLOG = GetNewDialog( kDialogResID, 
         NULL, kMoveToFront );

If the DLOG couldn't be loaded, beep once then exit.

   if ( gSettingsDLOG == NULL )
   {
      SysBeep( 10 );   /* Couldn't load the DLOG resource!!! */
      ExitToShell();
   }

Once the DLOG is loaded, make the dialog window visible and the current port.

   ShowWindow( gSettingsDLOG );
   SetPort( gSettingsDLOG );

Next, turn the current radio button on.

   curRadioButton = gCurrentPICT - kBaseResID + kFirstRadio;
   GetDialogItem( gSettingsDLOG, curRadioButton, &itemType,
            &itemHandle, &itemRect );
   SetControlValue( (ControlHandle)itemHandle, kOn );
}

FlipControl() turns a radio button or check box that's on, off and one that's off, on.

/********** FlipControl **********/

void   FlipControl( ControlHandle control )
{
   SetControlValue( control, ! GetControlValue( control ) );
}

SwitchPICT() calls DisposeWindow() to free up the memory used by the specified window (this closes the window as well) and then calls CreateWindow() to create a My Pet Fred window that reflects or most current choice of pet.

/********** SwitchPICT **********/

void   SwitchPICT( void )
{
   DisposeWindow( gFredWindow );
   
   CreateWindow();
}

Running Modeless

Save your source code and you're ready to run. Select Run from the Project menu to compile and run your program. When the program runs, the My Pet Fred window will appear, showing PICT 128. Pull down the Apple menu and verify that the first item reads About Modeless. Select About Modeless. from the Apple menu and check out your About box. Are your changes all there? Click the OK button to dismiss the About box.

Hold down the mouse in the File menu and verify that the S command-key equivalent was added to the Settings item. Select Settings. The Settings dialog box should appear (Figure 12).

Figure 12. The Settings... modal dialog box.

Click the My Pet Fred window, bringing it to the front and sending the modeless dialog to the back. Notice that the radio buttons are dimmed when the dialog is no longer the front-most window (Figure 13).

Figure 13. The radio buttons are dimmed when the dialog box is not in front.

Now type the command-key equivalent S to bring the Settings dialog to the front again; the radio buttons should be enabled. Click the Elephant radio button. Notice that the My Pet Fred window changes appropriately, leaving the Settings window in front. Click a few more radio buttons. While you are at it, click the File menu. Notice that the Settings item has been dimmed. Though this doesn't help us much in this program, it's important to be able to disable and enable certain menu items when a modeless dialog is in front.

When you are satisfied with your pet selection, drag the Settings window to another part of your screen. Now click the close box. The Settings window disappears. Select Settings from the File menu. The Settings window reappears at the position it was in when it disappeared and with the same radio button settings.

Finally, type the command-key equivalent Q to exit the program.

Till Next Time...

Well, that's about it for modeless dialogs. Be sure to read the Inside Macintosh: Macintosh Toolbox Essentials chapters that pertain to dialogs and alerts. In a future column we'll spend some time with a filterProc, a procedure that you provide to the Toolbo, and that the Toolbox calls for you. The filterProc allows you to control how the user interact with a dialog box, including what text the user can type. You can read about filterProc in Inside Macintosh: Macintosh Toolbox Essentials in the description of the Dialog Manager routine ModalDialog().

 

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Netmarble is making some pretty big moves with their latest update for Seven Knights Idle Adventure, with a bunch of interesting additions. Two new heroes enter the battle, there are events and bosses abound, and perhaps most interesting, a huge... | Read more »
Make the passage of time your plaything...
While some of us are still waiting for a chance to get our hands on Ash Prime - yes, don’t remind me I could currently buy him this month I’m barely hanging on - Digital Extremes has announced its next anticipated Prime Form for Warframe. Starting... | Read more »
If you can find it and fit through the d...
The holy trinity of amazing company names have come together, to release their equally amazing and adorable mobile game, Hamster Inn. Published by HyperBeard Games, and co-developed by Mum Not Proud and Little Sasquatch Studios, it's time to... | Read more »
Amikin Survival opens for pre-orders on...
Join me on the wonderful trip down the inspiration rabbit hole; much as Palworld seemingly “borrowed” many aspects from the hit Pokemon franchise, it is time for the heavily armed animal survival to also spawn some illegitimate children as Helio... | Read more »
PUBG Mobile teams up with global phenome...
Since launching in 2019, SpyxFamily has exploded to damn near catastrophic popularity, so it was only a matter of time before a mobile game snapped up a collaboration. Enter PUBG Mobile. Until May 12th, players will be able to collect a host of... | Read more »
Embark into the frozen tundra of certain...
Chucklefish, developers of hit action-adventure sandbox game Starbound and owner of one of the cutest logos in gaming, has released their roguelike deck-builder Wildfrost. Created alongside developers Gaziter and Deadpan Games, Wildfrost will... | Read more »
MoreFun Studios has announced Season 4,...
Tension has escalated in the ever-volatile world of Arena Breakout, as your old pal Randall Fisher and bosses Fred and Perrero continue to lob insults and explosives at each other, bringing us to a new phase of warfare. Season 4, Into The Fog of... | Read more »
Top Mobile Game Discounts
Every day, we pick out a curated list of the best mobile discounts on the App Store and post them here. This list won't be comprehensive, but it every game on it is recommended. Feel free to check out the coverage we did on them in the links below... | Read more »
Marvel Future Fight celebrates nine year...
Announced alongside an advertising image I can only assume was aimed squarely at myself with the prominent Deadpool and Odin featured on it, Netmarble has revealed their celebrations for the 9th anniversary of Marvel Future Fight. The Countdown... | Read more »

Price Scanner via MacPrices.net

Every model of Apple’s 13-inch M3 MacBook Air...
Best Buy has Apple 13″ MacBook Airs with M3 CPUs in stock and on sale today for $100 off MSRP. Prices start at $999. Their prices are the lowest currently available for new 13″ M3 MacBook Airs among... Read more
Sunday Sale: Apple iPad Magic Keyboards for 1...
Walmart has Apple Magic Keyboards for 12.9″ iPad Pros, in Black, on sale for $150 off MSRP on their online store. Sale price for online orders only, in-store price may vary. Order online and choose... Read more
Apple Watch Ultra 2 now available at Apple fo...
Apple has, for the first time, begun offering Certified Refurbished Apple Watch Ultra 2 models in their online store for $679, or $120 off MSRP. Each Watch includes Apple’s standard one-year warranty... Read more
AT&T has the iPhone 14 on sale for only $...
AT&T has the 128GB Apple iPhone 14 available for only $5.99 per month for new and existing customers when you activate unlimited service and use AT&T’s 36 month installment plan. The fine... Read more
Amazon is offering a $100 discount on every M...
Amazon is offering a $100 instant discount on each configuration of Apple’s new 13″ M3 MacBook Air, in Midnight, this weekend. These are the lowest prices currently available for new 13″ M3 MacBook... Read more
You can save $300-$480 on a 14-inch M3 Pro/Ma...
Apple has 14″ M3 Pro and M3 Max MacBook Pros in stock today and available, Certified Refurbished, starting at $1699 and ranging up to $480 off MSRP. Each model features a new outer case, shipping is... Read more
24-inch M1 iMacs available at Apple starting...
Apple has clearance M1 iMacs available in their Certified Refurbished store starting at $1049 and ranging up to $300 off original MSRP. Each iMac is in like-new condition and comes with Apple’s... Read more
Walmart continues to offer $699 13-inch M1 Ma...
Walmart continues to offer new Apple 13″ M1 MacBook Airs (8GB RAM, 256GB SSD) online for $699, $300 off original MSRP, in Space Gray, Silver, and Gold colors. These are new MacBook for sale by... Read more
B&H has 13-inch M2 MacBook Airs with 16GB...
B&H Photo has 13″ MacBook Airs with M2 CPUs, 16GB of memory, and 256GB of storage in stock and on sale for $1099, $100 off Apple’s MSRP for this configuration. Free 1-2 day delivery is available... Read more
14-inch M3 MacBook Pro with 16GB of RAM avail...
Apple has the 14″ M3 MacBook Pro with 16GB of RAM and 1TB of storage, Certified Refurbished, available for $300 off MSRP. Each MacBook Pro features a new outer case, shipping is free, and an Apple 1-... Read more

Jobs Board

*Apple* Systems Administrator - JAMF - Activ...
…**Public Trust/Other Required:** None **Job Family:** Systems Administration **Skills:** Apple Platforms,Computer Servers,Jamf Pro **Experience:** 3 + years of Read more
IT Systems Engineer ( *Apple* Platforms) - S...
IT Systems Engineer ( Apple Platforms) at SpaceX Hawthorne, CA SpaceX was founded under the belief that a future where humanity is out exploring the stars is Read more
Nurse Anesthetist - *Apple* Hill Surgery Ce...
Nurse Anesthetist - Apple Hill Surgery Center Location: WellSpan Medical Group, York, PA Schedule: Full Time Sign-On Bonus Eligible Remote/Hybrid Regular Apply Now Read more
Housekeeper, *Apple* Valley Village - Cassi...
Apple Valley Village Health Care Center, a senior care campus, is hiring a Part-Time Housekeeper to join our team! We will train you for this position! In this role, Read more
Sublease Associate Optometrist- *Apple* Val...
Sublease Associate Optometrist- Apple Valley, CA- Target Optical Date: Apr 20, 2024 Brand: Target Optical Location: Apple Valley, CA, US, 92307 **Requisition Read more
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