Difference between revisions of "Mac OS X Implementing HIView"

Revision as of 21:21, 12 March 2007

Contributors

Eric Bachard[ericb]

Sébastien Plisson [plipli]

Introduction

[DRAFT]  : means, not yet working, work in progress ...

HIObject is a common base class for all user interface objects and all menus, windows, controls, toolbars, and so on, are subclasses of HIObject.

HIView is an object-oriented view system subclassed from HIObject. All controls are implemented as HIView objects ("views"). You can easily subclass HIView classes, making it easy to implement custom controls. Over time the HIView API will replace the current Control Manager. See [HIView intro]

The main idea behind HIView is to superpose plans, to create any view, using compositing possibilities of Quartz Graphical Engine.

The final result is the superposition of all plans, following simple rules like :

- The last plan is always drawn on the previous one ;
- Some plans can  be declared visible, or not, very easely.

This page is part of [Native Controls Implementation] and the objective is to use HIView for HIComboboxes or other HI* controls.

Our objective is to bind vcl controls with HI* controls, from Carbon API.

e.g.  : implement HICombobox as one control only.

The generic implementation, under tests (and not fully working), uses :

HI* events definitions in aquavclevents.hxx

Event handler implementation in HandleHIViewEvent()

The use of HandleHIViewEvent() in AquaSalFrame::CreateNewSystemWindow()

The use of HI* controls, in vcl, when ::CreateNewSystemWindow() is used, calling HandleHIViewEvent(), when HI* events are detected in the frame.

Note : we "or"- ed kWindowCompositingAttribute in nWindowAttributes, to see compositing effects. [FIXME] : investigate, because use this attribute causes refresh issues

Current code implementation

Events for HIView

Two sorts of events are needed:

• for objects (ClasskEventClassHIObject )  :

kEventHIObjectConstruct

kEventHIObjectInitialize

kEventHIObjectDestruct

• for controls themselves ( Class kEventClassControl ) :

kEventControlDraw 

kEventControlInitialize

kEventControlHitTest

kEventControlGetPartRegion

Current implementation : see vcl/aqua/aquavclevents.hxx for more informations about the syntax.

Install Event Handler

Now we have to install event Handler, inside AquaSalFrame::CreateNewSystemWindow() :

InstallEventHandler (
                           GetControlEventTarget (mhView),
                           NewEventHandlerUPP (HandleHIViewEvent),
                           GetEventTypeCount (cHIViewEvent),
                           cHIViewEvent,
                           (void*)mhView, // note the use of the pointer 
                           NULL
                           );

The HI* Event Handler

The Handler is OSStatus type, and is used when events are detected.

e.g.  : we created HandleHIViewEvent()

using GetEventParameter, itself using the parameters described in Apple documentation.

Code sample :

OSStatus HandleHIViewEvent(EventHandlerCallRef inHandlerCallRef, EventRef inEvent, void* inUserData)
{ 
    //lock
    ImplSalYieldMutexAcquire();
    
    
    OSStatus status = noErr;
    
    // we use mrContext, global and seen from everywhere 
    CGContextRef mrContext; 
    
    // create HIRect, contianing the control bounds ( in local coordinates) 
    HIRect bounds;  

    status = GetEventParameter (inEvent, 
                                kEventParamCGContextRef, 
                                typeCGContextRef, 
                                NULL, 
                                sizeof (CGContextRef), 
                                NULL, 
                                &mrContext); 

    // not used, but usefull
    //require_noerr(status, CantGetGraphicsContext); // 2
    
   
    // We need to know the bounds containing the current control 
    HIViewGetBounds ((HIViewRef) inUserData, &bounds); 

    // not used, but usefull
    //require_noerr(status, CantGetBoundingRectangle);

    // unlock 
    ImplSalYieldMutexRelease();
    
    return status;  
} 

HIView use in AquaSalFrame::CreateNewSystemWindow()

Code sample :

   
    //  TEST HIVIew part 
    // Set mhView with HIView Content ViewRef
  
        HIRect myViewRect;
        myViewRect.origin.x = aContentRect.left; 
        myViewRect.origin.y = aContentRect.right; 
        myViewRect.size.width = aContentRect.right-aContentRect.left; 
        myViewRect.size.height = aContentRect.bottom-aContentRect.top; 
        OSStatus errval;
        errval = HIViewFindByID(HIViewGetRoot(mrWindow), kHIViewWindowContentID, &mhView); 

        // make the view visible                        
        HIViewSetVisible (mhView, true); 
        
        // set the frame
        HIViewSetFrame (mhView, &myViewRect);

Controls

[FIXME]

Example : HICombobox

-> code located in vcl/aqua/source/gdi/salnativewidgets.cxx , where all NWF are defined

1) declare CTRL_COMBOBOX control as "true" in isNativeControlSupported()

2) get the control region in getNativeControlRegion()

3) add CTRL_COMBOBOX case in drawNativeControl()

Code sample for the last part (Warning : not yet working !! ) :

 switch( nType )
    {
            
        case CTRL_COMBOBOX:
        if ( ( nPart==PART_BUTTON_DOWN) ||  (nPart==PART_SUB_EDIT) || (nPart==PART_ENTIRE_CONTROL) || (nPart==HAS_BACKGROUND_TEXTURE))

        .... (other code ) 

                if( BeginGraphics() )
                {
                    HIViewRef myCombo;
                    
                    HIRect rc2;
                    
                    rc2.origin.x = rControlRegion.GetBoundRect().Left();
                    rc2.origin.y = rControlRegion.GetBoundRect().Top();
                    rc2.size.width = rControlRegion.GetBoundRect().GetWidth();
                    rc2.size.height = rControlRegion.GetBoundRect().GetHeight();

                    HIComboBoxCreate ( &rc2 , NULL, NULL, NULL, kHIComboBoxStandardAttributes, &myCombo);
                    HIViewSetVisible ( myCombo, true);
                    HIViewAddSubview (mrView, myCombo); 
                    HIViewSetNeedsDisplay (myCombo, true);
                    					
                    EndGraphics();
                    return true;
                }

      .....  (other code )

Usefull Links

References

[Introducing HIView]

OverView : [HIToolbox]

HIVIew  : [reference] [or .pdf format]

[Upgrading to HIToolbox]

Code sample

High Level Toolbox, HIServices Release Notes : http://developer.apple.com/releasenotes/Carbon/RN-HIToolbox/