SWT: A Developer's Notebook

Allowing Additions to the Combo List

Up until now, the examples have contained only a READ_ONLY -style combo. In that mode, the text field portion of the combo cannot be directly edited by the user. The user must select an item from the list, at which time that item will be displayed in read-only mode in the text field. However, the combo can also be configured to enable the user to enter text in the text portion that is not represented by a corresponding item on the list.

How do I do that?

To permit the user to enter text in the text portion of the combo that does not directly correspond to an item in the list portion, just use the SWT.DROP_DOWN style when you create the combo:

final Combo c1 = new Combo(s, SWT.DROP_DOWN);

As seen in Figure 8-5, drop-down-style combos have a slightly different look on the Windows platform. When the text portion has focus, you see a different mouse cursor, usually an I-beam, which indicates that the text field is editable.

Figure 8-5. The DROP_DOWN style

Note

Remember, since SWT will run in native code, the look and feel of the Combo will be different across platforms.

Since the combo now has a completely functional text field, the user can enter any text in the combo and is not limited to simply choosing an item on the list. This also opens up your code for the use of some text-field-specific methods, many of which will be familiar from the Chapter 5