// some imports...
import de.itemis.utils.jface.viewers.StyledTextCellEditor;
import de.itemis.xtext.utils.jface.viewers.XtextStyledTextCellEditor;
// other imports...

public class MyDirectEditFeature extends
		AbstractDirectEditingFeature implements ICellEditorProvider {

Rectangle rectangle = null; // initialized in my canDirectEdit Method

/* ... */
@Override
public int getEditingType() {
	return TYPE_CUSTOM;
}
/* ... */

@Override
public CellEditor createCellEditor(Composite parent) {

	StyledTextCellEditor cellEditor;
	Injector myInjector = MyDslActivator.getInstance().getInjector("myDSL")
	cellEditor = new XtextStyledTextCellEditor(SWT.SINGLE, myInjector);
	cellEditor.create(parent);
	
	StyledText text = (StyledText) cellEditor.getControl();
	text.setBounds(rectangle);
	return cellEditor;
}

@Override
public void relocate(CellEditor cellEditor, IFigure figure) {
	// Nothing
}

/* ... */
}