contacts.c

CD_《Palm OS编程实践》

// CH.2 The super-include for PalmOS
#include <Pilot.h>

// CH.3 Our resource file
#include "Contacts_res.h"

// CH.3 Prototypes for our event handler functions
static Boolean contactDetailHandleEvent( EventPtr event );
static Boolean aboutHandleEvent( EventPtr event );
static Boolean menuEventHandler( EventPtr event );

// CH.3 Our field memory handle
static Handle htext;	// CH.3 Handle to the text in our edit field
#define HTEXT_SIZE 81	// CH.3 Size of our edit field

// CH.4 Constants for ROM revision
#define ROM_VERSION_2	0x02003000
#define ROM_VERSION_MIN	ROM_VERSION_2

// CH.2 The main entry point
DWord PilotMain( Word cmd, Ptr, Word )
{
    DWord 		romVersion;	// CH.4 ROM version
	FormPtr		form;	// CH.2 A pointer to our form structure
	Handle		hsrc;	// CH.3 Handle to the string resource
	CharPtr 	psrc;	// CH.3 Points to the text in the resource
	CharPtr 	ptext;	// CH.3 Points to the text in the edit field
	EventType	event;	// CH.2 Our event structure
	Word		error;	// CH.3 Error word

    // CH.4 Get the ROM version
    romVersion = 0;
    FtrGet( sysFtrCreator, sysFtrNumROMVersion, &romVersion );

	// CH.4 If we are below our minimum acceptable ROM revision
    if( romVersion < ROM_VERSION_MIN )
    {
        // CH.4 Display the alert
        FrmAlert( LowROMVersionErrorAlert );

        // CH.4 PalmOS 1.0 will continuously re-launch this app
        // unless we switch to another safe one
        if( romVersion < ROM_VERSION_2 )
        {
            AppLaunchWithCommand( sysFileCDefaultApp,
                    sysAppLaunchCmdNormalLaunch, NULL );
        }
        return( 0 );
    }

	// CH.2 If this is not a normal launch, don't launch
	if( cmd != sysAppLaunchCmdNormalLaunch )
		return( 0 );

	// CH.3 Get the initialization string resource handle
	hsrc = DmGetResource( strRsc, FieldInitString );
	
	// CH.3 Lock the resource, get the pointer
	psrc = MemHandleLock( hsrc );
	
	// CH.3 Allocate our field chunk
	htext = MemHandleNew( HTEXT_SIZE );
	if( htext == NULL )
		return( 0 );
	
	// CH.3 Lock the memory, get the pointer
	ptext = MemHandleLock( htext );
	
	// CH.3 Initialize it
	StrCopy( ptext, psrc );
	
	// CH.3 Unlock the field's memory
	MemHandleUnlock( htext );

	// CH.3 Unlock the resource's memory
	MemHandleUnlock( hsrc );

	// CH.3 Release the string resource
	DmReleaseResource( hsrc );

	// CH.4 Go to our starting page
	FrmGotoForm( ContactDetailForm );

	// CH.2 Our event loop
	do
	{
		// CH.2 Get the next event
		EvtGetEvent( &event, -1 );

		// CH.2 Handle system events
		if( SysHandleEvent( &event ) )
			continue;

		// CH.3 Handle menu events
		if( MenuHandleEvent( NULL, &event, &error ) )
			continue;

		// CH.4 Handle form load events
		if( event.eType == frmLoadEvent )
		{
			// CH.4 Initialize our form
			switch( event.data.frmLoad.formID )
			{
				// CH.4 Contact Detail form
				case ContactDetailForm:
					form = FrmInitForm( ContactDetailForm );
					FrmSetEventHandler( form, contactDetailHandleEvent );
				break;
				
				// CH.4 About form
				case AboutForm:
					form = FrmInitForm( AboutForm );
					FrmSetEventHandler( form, aboutHandleEvent );
				break;
			}				
			FrmSetActiveForm( form );
		}
			
		// CH.2 Handle form events
		FrmDispatchEvent( &event );
		
	// CH.2 If it's a stop event, exit
	} while( event.eType != appStopEvent );


    // CH.4 Deallocate memory
    MemHandleFree( htext );
	
	// CH.2 We're done
	return( 0 );
}

// CH.4 Our Contacts form handler function
static Boolean contactDetailHandleEvent( EventPtr event )
{
	FormPtr		form;	// CH.3 A pointer to our form structure
    Word        index;  // CH.3 A general purpose index
    FieldPtr    field;  // CH.3 Used for manipulating fields
    
	// CH.3 Get our form pointer
	form = FrmGetActiveForm();

	// CH.4 Parse events
	switch( event->eType )
	{
		// CH.4 Form open event
		case frmOpenEvent:
		{
		    // CH.3 Get the index of our field
		    index = FrmGetObjectIndex( form, ContactDetailFirstNameField );

		    // CH.3 Get the pointer to our field
		    field = FrmGetObjectPtr( form, index );

		    // CH.3 Set the editable text
		    FldSetTextHandle( field, htext );

		    // CH.2 Draw the form
		    FrmDrawForm( form );

		    // CH.3 Set the focus to our field
		    FrmSetFocus( form, index );
		}
		break;
	
		// CH.4 Form close event
		case frmCloseEvent:
		{
		    // CH.3 Get the index of our field
		    index = FrmGetObjectIndex( form, ContactDetailFirstNameField );

		    // CH.3 Get the pointer to our field
		    field = FrmGetObjectPtr( form, index );

		    // CH.4 Unlink our handle from the field
		    FldSetTextHandle( field, NULL );
		}
		break;
	
		// CH.3 Parse menu events
		case menuEvent:
			return( menuEventHandler( event ) );
		break;
	}

	// CH.2 We're done
	return( false );
}

// CH.4 Our About form event handler function
static Boolean aboutHandleEvent( EventPtr event )
{
	FormPtr		form;	// CH.4 A pointer to our form structure

	// CH.4 Get our form pointer
	form = FrmGetActiveForm();

	// CH.4 Respond to the Open event
	if( event->eType == frmOpenEvent )
	{
		// CH.4 Draw the form
		FrmDrawForm( form );
	}
	
	// CH.4 Return to the calling form
    if( event->eType == ctlSelectEvent )
    {
		FrmReturnToForm( 0 );
		
		// CH.4 Always return true in this case
		return( true );
	}

	// CH.4 We're done
	return( false );
}

// CH.3 Handle menu events
Boolean menuEventHandler( EventPtr event )
{
	FormPtr		form;		// CH.3 A pointer to our form structure
	Word		index;		// CH.3 A general purpose control index
	FieldPtr	field;		// CH.3 Used for manipulating fields

	// CH.3 Get our form pointer
	form = FrmGetActiveForm();

	// CH.3 Erase the menu status from the display
	MenuEraseStatus( NULL );
			
	// CH.4 Handle options menu
	if( event->data.menu.itemID == OptionsAboutContacts )
	{
		// CH.4 Pop up the About form as a Dialog
		FrmPopupForm( AboutForm );
		return( true );
	}
		
	// CH.3 Handle graffiti help
	if( event->data.menu.itemID == EditGraffitiHelp )
	{
		// CH.3 Pop up the graffiti reference based on
		// the graffiti state
		SysGraffitiReferenceDialog( referenceDefault );
		return( true );
	}

	// CH.3 Get the index of our field
	index = FrmGetFocus( form );
			
	// CH.3 If there is no field selected, we're done
	if( index == noFocus )
		return( false );
			
	// CH.3 Get the pointer of our field
	field = FrmGetObjectPtr( form, index );
			
	// CH.3 Do the edit command
	switch( event->data.menu.itemID )
	{
		// CH.3 Undo
		case EditUndo:
			FldUndo( field );
		break;
		
		// CH.3 Cut
		case EditCut:
			FldCut( field );
		break;
				
		// CH.3 Copy
		case EditCopy:
			FldCopy( field );
		break;
			
		// CH.3 Paste
		case EditPaste:
			FldPaste( field );
		break;
				
		// CH.3 Select All
		case EditSelectAll:
		{
			// CH.3 Get the length of the string in the field
			Word length = FldGetTextLength( field );
				
			// CH.3 Sound an error if appropriate
			if( length == 0 )
			{
				SndPlaySystemSound( sndError );
				return( false );
			}
			
			// CH.3 Select the whole string
			FldSetSelection( field, 0, length );					
		}
		break;
				
		// CH.3 Bring up the keyboard tool
		case EditKeyboard:
			SysKeyboardDialogV10();
		break;
	}
	
	// CH.3 We're done	
	return( true );
}