Re: Finder-like color label menu item in Cocoa?

FROM : Pascal Pochet
DATE : Sun Jul 23 09:49:37 2006

Le 23-juil.-06 à 08:09, James Bucanek a écrit :

> Is it possible (or even better yet, has someone already written it) 
> to implement a menu item like the Finder's color label selector?
>
> I'd like to do something similar in both the main menubar and a 
> contextual pop-menu.
>
> I assumed that this would be fait accompli, but several hours of 
> searching the Internet, list archives, and developer code examples 
> only resulted in two other posts asking the same question (both 
> went unanswered), no documentation on how one would accomplish 
> this, and no code samples.
>
> I did find an old Carbon project named MenuViews which purports to 
> implement this (I can't tell, because the project won't build). But 
> even if it did, I'm not optimistic that I could use it in a Cocoa 
> application.
>


MenuViews compiles fine as Universal binary…
but it generates a lot of "deprecated" warning…

To integrate it in a Cocoa project, you have to change 
LabelItemView.cp into a LabelItemView.mm to be able to mix with some 
Objective-C code…
the other changes are quite minimal:

extern OSStatus    HILabelViewCreate( MenuRef inMenu, MenuItemIndex 
inMenuItem, HIViewRef inMenuContentView, HIViewRef* outView );

->

extern OSStatus    HILabelViewCreate( MenuRef inMenu, MenuItemIndex 
inMenuItem, HIViewRef inMenuContentView, HIViewRef* outView, id 
target, SEL action );

(the action should be something like:
- (void)handleLabelSelected:(NSNumber *)inValue
but of course you could change it to fit your needs: just adapt 
HILabelView::ControlHit to pass the parameter you would like…
)

OSStatus
HILabelViewCreate( MenuRef inMenu, MenuItemIndex inMenuItem, 
HIViewRef inMenuContentView, HIViewRef* outView, id target, SEL action )
{
   return HILabelView::Create( inMenu, inMenuItem, inMenuContentView, 
outView, target, action );
}

OSStatus
HILabelView::Create(
   MenuRef            inMenu,
   MenuItemIndex    inMenuItem,
   HIViewRef        inMenuContentView,
   HIViewRef*        outView,
   id inTarget        ,
   SEL inAction )
{
   OSStatus    err = noErr;
   EventRef    event = CreateInitializationEvent(); // create 
initialization event
   
   require_action( event != NULL, CantCreateEvent, err = 
eventInternalErr );
   
   // add extra parameters
   if ( inMenu != NULL )
       SetEventParameter( event, kEventParamMenuRef, typeMenuRef, sizeof
( inMenu ), &inMenu );
   if ( inMenuItem != 0 )
       SetEventParameter( event, kEventParamMenuItemIndex, 
typeMenuItemIndex, sizeof( inMenuItem ), &inMenuItem );
   if ( inMenuContentView != 0 )
       SetEventParameter( event, kEventParamControlRef, typeControlRef, 
sizeof( inMenuContentView ), &inMenuContentView );

   SetEventParameter( event, 'targ', typeVoidPtr, sizeof( inTarget ), 
&inTarget );
   SetEventParameter( event, 'acti', typeVoidPtr, sizeof( inAction ), 
&inAction );
   
   // register the subclass
   static bool sRegistered = false;
   if( !sRegistered )
   {
       RegisterSubclass( kTViewHILabelViewClassID, Construct );
       sRegistered = true;
   }
   
   // instantiate the object
   err = HIObjectCreate( kTViewHILabelViewClassID, event, 
(HIObjectRef*) outView );
       
   ReleaseEvent( event );

CantCreateEvent:
   
   return err;
}


OSStatus
HILabelView::Initialize(
   TCarbonEvent&        inEvent )
{
...

   if ( fMenu != NULL )
   {
...
       inEvent.GetParameter( 'targ', typeVoidPtr, sizeof( id ), &fTarget );
       inEvent.GetParameter( 'acti', typeVoidPtr, sizeof( SEL ), 
&fSelector );
   }
   
CantInitBaseClass:

   return err;
}

in class HILabelView
add the fields
       id                        fTarget        ;
       SEL                        fSelector    ;


And

OSStatus
HILabelView::ControlHit( HIViewPartCode inPart, UInt32 inModifiers )
{
   UInt32 oldSelected = fSelected;
   
// here the labels are ORed, (NOT Finder-like) : change to fit your 
needs…
   if ( inPart == 1 )
       fSelected = 0;
   else
       fSelected ^= 1 << ( inPart - 1 );
       
   if ( oldSelected != fSelected )    {
       HIViewSetNeedsDisplay( GetViewRef(), true );
       if (fTarget)
           objc_msgSend(fTarget, fSelector, [NSNumber 
numberWithInt:fSelected])    ;
   }
       
   return noErr;
}


Pascal Pochet
<email_removed>