Re: [ve-dev] Help with generating complex constraint objects

[Rich Kulp <richkulp@xxxxxxxxxx>]

Hi,

This section from BoxLayoutPolicyFactory
would be the best:

         
      PTClassInstanceCreation ic = InstantiationFactory.eINSTANCE.createPTClassInstanceCreation()
;
         
      ic.setType("javax.swing.BoxLayout")
; //$NON-NLS-1$
         
      
         
      //
set the arguments
         
      PTInstanceReference ir = InstantiationFactory.eINSTANCE.createPTInstanceReference()
;
         
      ir.setReference(container) ;    
   
         
      PTFieldAccess fa = InstantiationFactory.eINSTANCE.createPTFieldAccess();
       
         
      PTName name = InstantiationFactory.eINSTANCE.createPTName("javax.swing.BoxLayout")
; //$NON-NLS-1$
         
      if
(javaClass.getName().equals("BoxLayoutY_Axis"))
{ //$NON-NLS-1$
         
              fa.setField("Y_AXIS");
//$NON-NLS-1$ 
         
      } else
{
         
              fa.setField("X_AXIS");
       //
default to X_AXIS //$NON-NLS-1$
         
      }          
     
         
      fa.setReceiver(name) ;
         
              
         
      ic.getArguments().add(ir);
         
      ic.getArguments().add(fa) ;
         
      
         
      JavaAllocation alloc = InstantiationFactory.eINSTANCE.createParseTreeAllocation(ic);
       
         
      JavaHelpers boxLayoutJavaClass = JavaRefFactory.eINSTANCE.reflectType("javax.swing.BoxLayout",
rset); //$NON-NLS-1$
               
         
      
         
      return
BeanUtilities.createJavaObject(boxLayoutJavaClass, rset, alloc);

To change it to be to allocation something
like new FormLayout("a", "b") would be:

         
      JavaHelpers formLayoutJavaClass = JavaRefFactory.eINSTANCE.reflectType("x.y.FormLayout",
rset); //$NON-NLS-1$
         
      PTClassInstanceCreation ic = InstantiationFactory.eINSTANCE.createPTClassInstanceCreation()
;
         
      ic.setType(formLayoutJavaClass.getQualifiedNameForReflection())
; //$NON-NLS-1$
         
      
         
      //
set the arguments.
         
      PTStringLiteral arg1 = InstantiationFactory.eINSTANCE.createPTStringLiteral();
         
      arg1.setLiteralValue("a");
         
      PTStringLiteral arg2 = InstantiationFactory.eINSTANCE.createPTStringLiteral();
         
      arg2.setLiteralValue("b");
         
      ic.getArguments().add(arg1);
         
      ic.getArguments().add(arg2) ;
         
      
         
      JavaAllocation alloc = InstantiationFactory.eINSTANCE.createParseTreeAllocation(ic);
       
         
      return
BeanUtilities.createJavaObject(formLayoutJavaClass, rset, alloc);

Basically what we are doing here is
creating the initialization as a tree of expressions needed to execute
to produce the final result. The tree here is the new class _expression_,
that takes two arguments, which are each a string literal _expression_. The
reason we want the tree is so that we don't have to parse it to evaluate
it. Field references give us a big problem if not using a parse tree because
it is hard to tell if x.y.Z.g is a reference to field g of class x.y.Z
or is it an inner class g of class x.y.Z. With the parse tree you can't
make that confusion because they are physically different types of nodes
in the parse tree.

If your string literals where actually
static field references to some common code, such as is done with BoxLayout
and the references to javax.swing.BoxLayout.X_AXIS fields, then you would
use the field reference type of argument shown in the BoxLayout example.


For your ints in the CellConstraint,
if they are literals you would use (for an argument with the value 3):

         
      PTNumberLiteral arg1 = InstantiationFactory.eINSTANCE.createPTNumberLiteral("3");

Thanks,
Rich

Gerald Rosenberg <gerald@xxxxxxxxxx>
Sent by: ve-dev-bounces@xxxxxxxxxxx

06/01/2006 01:39 AM

Please respond to
Discussions people developing code for the Visual Editor project <ve-dev@xxxxxxxxxxx>

To	ve-dev@xxxxxxxxxxx
cc
Subject	Re: [ve-dev] Help with generating complex constraint objects

Thanks.

(My target platform is Eclipse 3.2 and VE 1.2.  Development platform
is Callisto 3.2RC3.)

Next question is how to provide arguments to constructors as generated.
 I am able to automatically generate this code on a layoutswitch:

private JPanel getJPanel() {

if
(jPanel
== null)
{ 
FormLayout formLayout = new
FormLayout(); 
formLayout.setRowGroups(new
int[][]
{}); 
formLayout.setColumnGroups(new
int[][]
{}); 
jPanel
= new
JPanel(); 
jPanel.setLayout(formLayout);

jPanel.add(getJButton1(),
new
CellConstraints());

jPanel.add(getJButton2(),
new
CellConstraints()); 
}

return
jPanel;

}

However, ...
The FormLayout signature as generated needs to be "new FormLayout(String,
String)" 
The CellConstratins signature as generated needs to be "new CellConstraints(int,
int, int, int)"

I am currently following the pattern of GridLayoutSwitcher to specify the
form layout manager and create the "setRowGroups/setColumnGroups"
initializers.  Not obvious how to also specify constructor arguments.

BoxLayout appears to be able to specify constructor arguments, but I have
not succeeded in tracing through the source to see how it is done.

A pointer to the right place in the code to look and/or an explanation
of the right methods to use would be appreciated.

Gerald


At 05:46 PM 5/31/2006, you wrote:


Hi, 

Sorry, but the current code parsing doesn't understand method calls to
anything other than  getControl().getName() for the constraint argument
in the add call. It only understands the getName() against a component
and field references and literals like String and numbers and new class
creation calls. 

So if you change to instead of your format to (Note: This is in VE 1.2.
I don't know if this works in VE 1.1, we made many changes since then):

jPanel.add(getJButton1(), new
CellConstraint(1,1))

we would be able to parse and understand this, assuming the FormLayout
you created would take a "CellConstraint" as a constraint.

You can open an enhancement request against VE to allow method calls there
instead. 

Rich _______________________________________________
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