Bug 123758 [DataBinding] CComboUpdatableValue Doesn't Handle Text That Isn't in The List of Selected Items
The current implementation of CComboUpdatableValue will only allow setting text if the value is in the list of possible selection values. In reality the CCombo allows either a manually entered value (which may not be in the list) or the selection of a value from the drop down list. I'll be submitting a patch for this shortly.
tests/org.eclipse.jface.tests.databinding/src/org/eclipse/jface/tests/databinding/scenarios/ReadOnlyComboScenarios.java
"TinkerLand", "DreamLand" };
		combo.setItems(items);
		Account account = (Account) catalog.getAccounts()[0];
		
		getDbc().bind(
				new Property(combo, SWTProperties.SELECTION),
				new Property(account, "country"), null);
		
		int index = 3;
		combo.setText(items[index]); 
		assertEquals(account.getCountry(), items[index]);
		
		index = 1;
		account.setCountry(items[index]);
		assertEquals(index, combo.getSelectionIndex());
		assertEquals(combo.getText(), items[index]);
		index = combo.getSelectionIndex();
		String txt = combo.getText();
		
		account.setCountry("FooBar");
		
		assertEquals(combo.getSelectionIndex(), index);
		assertEquals(combo.getText(), txt);
	}
	/**
	 * This scenario tests a simple SWT combo that is bound to a list of Country
	 * objects. The Country object's name property is listed in the Combo.
	 * 
	 * The Combo's selection is bounded to the Country property of an Account.
	 */