how to bind a property to a JLabel?

[Ichthyostega]

Hi,

maybe someone can point me to some doc/ or example code...?

I want to do the following:
My databean has a property (which is not readonly, i.e. it has a
getter and a setter). Now, when building a form, I want to bind this
property to a JLabel fileld, so it is visible just as information, but can't
be edited and doesn't look like a disabled input field. Is there any
"standard" way of achieving this?

thanks,
Hermann Vosseler

[LievenDoclo]

Hi and welcome.

I don't think there's a binder in RCP that handles JLabels, but you could easily make one yourself.

I've made a binding that binds String properties to a label:

public class StringLabelBinding extends CustomBinding
{

    private JTextField label;

    public StringLabelBinding(FormModel formModel, String formPropertyPath)
    {
        this(new JTextField(), formModel, formPropertyPath);
    }

    public StringLabelBinding(JTextField label, FormModel formModel, String formPropertyPath)
    {
    	super(formModel, formPropertyPath, String.class);
        this.label = label;
    }

    @Override
    protected void valueModelChanged(Object newValue)
    {
        label.setText((String) newValue);

    }

    @Override
    protected JComponent doBindControl()
    {
        return label;
    }

    @Override
    protected void enabledChanged()
    {
        label.setEnabled(isEnabled());

    }

    @Override
    protected void readOnlyChanged()
    {
        label.setEditable(!isReadOnly());
    }
    
    @Override
    protected boolean isReadOnly()
    {
        return true;
    }

}

The binder is equally simple:

public class StringLabelBinder implements Binder
{
    @Override
    public Binding bind(FormModel formModel, String formPropertyPath, Map context)
    {
        return new StringLabelBinding(formModel, formPropertyPath);
    }

    @Override
    public Binding bind(JComponent control, FormModel formModel, String formPropertyPath, Map context)
    {
        if (control instanceof JTextField)
        {
            return new StringLabelBinding((JTextField) control, formModel, formPropertyPath);
        }
        else
        {
            throw new IllegalArgumentException("This binding's control must be a JTextField");
        }
    }

}

Have fun!

[prashantbhat]

You can use:

getBindingFactory().createBoundLabel(formProperty);

This is already available in SwingBindingFactory.

Regards,
Prashant

[LievenDoclo]

Ok, sorry, you're correct. However, this'll only work for String. If you want some more flexibility, you'll need to create a binder yourself. Say you want a label that shows the i18n value of an enum, you can easily adapt my binder to show enums.

With even more customisation, you could do something like:

A converter that you need to implement:

public interface StringConverter
{
    public String convertToString(Object toConvert);
}

And hand it to the slightly altered binder and binding:

public class StringLabelBinder implements Binder
{
    private StringConverter converter;

    public void setConverter(StringConverter converter) { this.converter = converter; }

    public StringConverter getConverter() 
    {
        if(converter == null)
        {
            converter = new Converter() { public String convertToString(Object object) { return object.toString(); } }
        }
        return converter;
    }
  
    @Override
    public Binding bind(FormModel formModel, String formPropertyPath, Map context)
    {
        return new StringLabelBinding(formModel, formPropertyPath, converter);
    }

    @Override
    public Binding bind(JComponent control, FormModel formModel, String formPropertyPath, Map context)
    {
        if (control instanceof JTextField)
        {
            return new StringLabelBinding((JTextField) control, formModel, formPropertyPath, converter);
        }
        else
        {
            throw new IllegalArgumentException("This binding's control must be a JTextField");
        }
    }
}

public class StringLabelBinding extends CustomBinding
{

    private JTextField label;
    private StringConverter converter;

    public StringLabelBinding(FormModel formModel, String formPropertyPath, StringConverter converter)
    {
        this(new JTextField(), formModel, formPropertyPath, converter);
    }

    public StringLabelBinding(JTextField label, FormModel formModel, String formPropertyPath, StringConverter converter)
    {
    	super(formModel, formPropertyPath, String.class);
        this.label = label;
        this.converter = converter;
    }

    @Override
    protected void valueModelChanged(Object newValue)
    {
        label.setText(converter.convertToString(newValue));

    }

    @Override
    protected JComponent doBindControl()
    {
        return label;
    }

    @Override
    protected void enabledChanged()
    {
        label.setEnabled(isEnabled());

    }

    @Override
    protected void readOnlyChanged()
    {
        label.setEditable(!isReadOnly());
    }
    
    @Override
    protected boolean isReadOnly()
    {
        return true;
    }

}

So now you have a flexible solution to show any object type in a label. You only need to implement the String converter and use that in the Binder.

But again, for Strings it's overkill, prashantbhat answer will do nicely.

[Ichthyostega]

oh thanks... this did the trick

also thanks to LievenDoclo for posting the flexible sollution; it may come in handy for another problem I'll probably have to solve next...

and btw, Spring RichClient rocks!
Hermann

[LievenDoclo]

and btw, Spring RichClient rocks!
Hermann

Tell me something I don't already know

By the way, a small correction, the above binder will show a non-editable jtextfield, not a label. With a label, you're not able to select to content, with the above binder, it's possible to do so.