swt conbo用法

import  org.eclipse.swt.SWT; import  org.eclipse.swt.events.SelectionAdapter; import  org.eclipse.swt.events.SelectionEvent; import  org.eclipse.swt.layout.GridLayout; import  org.eclipse.swt.widgets.Combo; import  org.eclipse.swt.widgets.Display; import  org.eclipse.swt.widgets.Shell; public   class  ComboTest {      public   static   void  main(String[] args) {         String[] WEEK  =  {  " Monday " ,  " Tuesday " ,  " Wednesday " };         Display display  =   new  Display();         Shell shell  =   new  Shell(display);         shell.setBounds( 500 ,  100 ,  500 ,  300 );         shell.setText( " Combo " );         shell.setLayout( new  GridLayout( 3 ,  true ));                   // 创建Combo组件，为下拉列表样式          final  Combo dc  =   new  Combo(shell, SWT.DROP_DOWN);         dc.setItems(WEEK);         dc.addSelectionListener( new  SelectionAdapter(){             @Override              public   void  widgetSelected(SelectionEvent e) {                 String key  =   "" + dc.getSelectionIndex();                 String value  =  dc.getText();                 System.out.println( " key: " + key + "     value: " + value);             }         });                   // 创建Combo组件，为下拉列表样式，且只读          final  Combo rc  =   new  Combo(shell, SWT.DROP_DOWN  |  SWT.READ_ONLY);          // 在界面中显示的是123         rc.add( " 123 " );          // 第一个值是key从0开始 ,第二个值为value         rc.setData( " 0 " ,  " 321 " );                  rc.add( " 456 " );         rc.setData( " 1 " ,  " 654 " );                  rc.addSelectionListener( new  SelectionAdapter(){             @Override              public   void  widgetSelected(SelectionEvent e) {                 String key  =   "" + rc.getSelectionIndex();                 System.out.println( " key: " + key);                 String value  =  (String) rc.getData(key);                 System.out.println( " key: " + key + "     value: " + value);             }         });          // rc.setItems(MONTHS);          // 创建Combo组件，为List组件样式         Combo sc  =   new  Combo(shell, SWT.SIMPLE);         sc.setItems(WEEK);         shell.open();          while  ( ! shell.isDisposed()) {             if  ( ! display.readAndDispatch()) {                display.sleep();           }      }      display.dispose();     } }