一、SWT簡介
Java語言的聲望和它在桌面應用程序(GUI程序)所取得的成就顯然極不相符，至今仍然很少能看到非常成功Java桌面程序。雖然有JBuilder，Netbean，JProbe等大型軟件作為代表，但這仍不能證明Java的GUI程序是成功的：它們的外觀總是和同一操作系統平台下的其它軟件顯得格格不入。對機器配置的需求也似乎永無止境，這使得它們只能被一些總是擁有當前最高性能PC的程序員們所容忍，或是那些不在乎金錢和時間的專業用戶所接受。對絕大多數計算機使用者來說，AWT或SWING代表著怪異的界面和無法接受的速度。Standard Widget Toolkit(SWT)或許是Java這一噩夢的終結者，廣大Java程序員終於可以開發出高效率的GUI程序，它們擁有標准的外觀，幾乎沒有人能看出你的程序是用Java寫出來的，更為重要的是，這些程序是跨平台的。
SWT本身僅僅是Eclipse組織為了開發Eclipse IDE環境所編寫的一組底層圖形界面 API。或許是無心插柳，或是有意為之，至今為止，SWT無論是在性能和外觀上，都超越了SUN公司提供的AWT和SWING。目前Eclipse IDE已經開發到了2.1版本，SWT已經十分穩定。這裡指的穩定應該包含兩層意思：
一是指性能上的穩定，其中的關鍵是源於SWT的設計理念。SWT最大化了操作系統的圖形構件API，就是說只要操作系統提供了相應圖形的構件，那麼SWT只是簡單應用JNI技術調用它們，只有那些操作系統中不提供的構件，SWT才自己去做一個模擬的實現。可以看出SWT的性能上的穩定大多時候取決於相應操作系統圖形構件的穩定性。
另一個穩定是指SWT API包中的類、方法的名稱和結構已經少有改變，程序員不用擔心由於Eclipse組織開發進度很快(Eclipse IDE每天都會有一個Nightly版本的發布)，而導致自己的程序代碼變化過大。從一個版本的SWT更新至另一版本，通常只需要簡單將SWT包換掉就可以了。
二、Eclipse3.0的SWT編程
1.SWT比AWT和Swing要快多，因為它是利用操作系統的界面組件生成UI的，在java桌面設計領域掀起一場革命
2.環境配置：
windows系統+eclipse3.0
3.具體操作：
(1).新建一java項目，命名SWT,文件結構如下：
+swt
+bin(編譯輸出)
+src(原文件)
+AddressBookUI.java
+swt-awt-win32-3062.dll(以下均從eclipse\plugins\org.eclipse.swt.win32_3.0.1\os\win32\x86下導入)
+swt-win32-3062.dll
+javaw.exe.manifest
(2).到項目的properties裡，在java build path | libraries裡將swt.jar導入
(3).AddressBookUI.java原代碼如下：
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.swt.SWT;
import org.eclipse.swt.widgets.Button;
import org.eclipse.swt.widgets.Group;
import org.eclipse.swt.widgets.Label;
import org.eclipse.swt.widgets.Text;
import org.eclipse.swt.widgets.*;
import org.eclipse.swt.events.SelectionAdapter;
import org.eclipse.swt.events.SelectionEvent;
public class AddressBookUI {
private Shell shell;
private Text miscText;
private Text addrText;
private Text emailText;
private Text phoneText;
private Text lnameText;
private Text fnameText;
private Button cancelButton;
private Button saveButton;
private Button nextButton;
private Button prevButton;
private Button editButton;
private Button deleteButton;
private Button newButton;
public static void main(String[] args) {
AddressBookUI window = new AddressBookUI();
window.open();
}
public void open() {
final Display display = new Display();
shell = new Shell();
shell.setSize(610, 477);
shell.setText("Address Book");
{
newButton = new Button(shell, SWT.NONE);
newButton.addSelectionListener(new SelectionAdapter() {
public void widgetSelected(SelectionEvent e) {
clearText();
setTextEditable(true);
enableEditButtons(false);
enableSaveButtons(true);
System.out.println("New button selected.");
}
});
newButton.setBounds(10, 380, 75, 35);
newButton.setText("New");
}
{
deleteButton = new Button(shell, SWT.NONE);
deleteButton.addSelectionListener(new SelectionAdapter() {
public void widgetSelected(SelectionEvent e) {
clearText();
System.out.println("Delete button selected.");
}
});
deleteButton.setBounds(85, 380, 75, 35);
deleteButton.setText("Delete");
}
{
editButton = new Button(shell, SWT.NONE);
editButton.addSelectionListener(new SelectionAdapter() {
public void widgetSelected(SelectionEvent e) {
setTextEditable(true);
enableEditButtons(false);
enableSaveButtons(true);
System.out.println("Edit button selected.");
}
});
editButton.setBounds(160, 380, 75, 35);
editButton.setText("Edit");
}
{
prevButton = new Button(shell, SWT.NONE);
prevButton.addSelectionListener(new SelectionAdapter() {
public void widgetSelected(SelectionEvent e) {
System.out.println("Previous button selected.");
}
});
prevButton.setBounds(265, 380, 75, 35);
prevButton.setText("Previous");
}
{
nextButton = new Button(shell, SWT.NONE);
nextButton.addSelectionListener(new SelectionAdapter() {
public void widgetSelected(SelectionEvent e) {
System.out.println("Next button selected.");
}
});
nextButton.setBounds(340, 380, 75, 35);
nextButton.setText("Next");
}
{
saveButton = new Button(shell, SWT.NONE);
saveButton.addSelectionListener(new SelectionAdapter() {
public void widgetSelected(SelectionEvent e) {
setTextEditable(false);
enableEditButtons(true);
enableSaveButtons(false);
System.out.println("Save button selected.");
}
});
saveButton.setBounds(445, 380, 75, 35);
saveButton.setText("Save");
saveButton.setEnabled(false);
}
{
cancelButton = new Button(shell, SWT.NONE);
cancelButton.addSelectionListener(new SelectionAdapter() {
public void widgetSelected(SelectionEvent e) {
setTextEditable(false);
enableEditButtons(true);
enableSaveButtons(false);
System.out.println("Cancel button selected.");
}
});
cancelButton.setBounds(520, 380, 75, 35);
cancelButton.setText("Cancel");
cancelButton.setEnabled(false);
}
{
final Group group = new Group(shell, SWT.NONE);
group.setText("Details");
group.setBounds(10, 10, 585, 355);
{
final Label label = new Label(group, SWT.NONE);
label.setBounds(10, 20, 135, 25);
label.setText("First Name:");
}
{
final Label label = new Label(group, SWT.NONE);
label.setBounds(10, 60, 135, 25);
label.setText("Last Name:");
}
{
final Label label = new Label(group, SWT.NONE);
label.setBounds(10, 100, 135, 25);
label.setText("Phone:");
}
{
final Label label = new Label(group, SWT.NONE);
label.setBounds(10, 140, 135, 25);
label.setText("Email:");
}
{
final Label label = new Label(group, SWT.NONE);
label.setBounds(10, 180, 135, 25);
label.setText("Address:");
}
{
final Label label = new Label(group, SWT.NONE);
label.setBounds(10, 255, 135, 25);
label.setText("Miscellaneous Information:");
}
{
fnameText = new Text(group, SWT.BORDER | SWT.READ_ONLY);
fnameText.setBounds(150, 15, 420, 25);
}
{
lnameText = new Text(group, SWT.BORDER | SWT.READ_ONLY);
lnameText.setBounds(150, 55, 420, 25);
}
{
phoneText = new Text(group, SWT.BORDER | SWT.READ_ONLY);
phoneText.setBounds(150, 95, 420, 25);
}
{
emailText = new Text(group, SWT.BORDER | SWT.READ_ONLY);
emailText.setBounds(150, 135, 420, 25);
}
{
addrText = new Text(group, SWT.BORDER | SWT.READ_ONLY | SWT.V_SCROLL);
addrText.setBounds(150, 175, 420, 60);
}
{
miscText = new Text(group, SWT.BORDER | SWT.READ_ONLY | SWT.V_SCROLL);
miscText.setBounds(150, 250, 420, 65);
}
}
setupMenu();
shell.open();
while (!shell.isDisposed()) {
if (!display.readAndDispatch())
display.sleep();
}
}
private void setupMenu() {
//create the menu bar
Menu menu = new Menu(shell, SWT.BAR);
shell.setMenuBar(menu);
//add the File option to it
MenuItem file = new MenuItem(menu, SWT.CASCADE);
file.setText("File");
//create a menu for the File option
file.setMenu(new Menu(file));
//add MenuItems to the File menu
MenuItem prevItem = new MenuItem(new Menu(file), SWT.NONE);
prevItem.setText("Previous");
MenuItem nextItem = new MenuItem(new Menu(file), SWT.PUSH);
nextItem.setText("Next");
MenuItem seperator = new MenuItem(new Menu(file), SWT.SEPARATOR);
MenuItem quitItem = new MenuItem(new Menu(file), SWT.PUSH);
quitItem.setText("Quit");
//add listeners for the actions
prevItem.addListener(SWT.Selection, new Listener() {
public void handleEvent(Event e) {
System.out.println("Previous menu item selected.");
}
});
nextItem.addListener(SWT.Selection, new Listener() {
public void handleEvent(Event e) {
System.out.println("Next menu item selected.");
}
});
quitItem.addListener(SWT.Selection, new Listener() {
public void handleEvent(Event e) {
shell.dispose();
}
});
}
private void clearText() {
fnameText.setText("");
lnameText.setText("");
phoneText.setText("");
emailText.setText("");
addrText.setText("");
miscText.setText("");
}
private void setTextEditable(boolean editable) {
fnameText.setEditable(editable);
lnameText.setEditable(editable);
phoneText.setEditable(editable);
emailText.setEditable(editable);
addrText.setEditable(editable);
miscText.setEditable(editable);
}
private void enableEditButtons(boolean enable) {
newButton.setEnabled(enable);
deleteButton.setEnabled(enable);
editButton.setEnabled(enable);
}
private void enableSaveButtons(boolean enable) {
saveButton.setEnabled(enable);
cancelButton.setEnabled(enable);
}
}
(4).測試運行，run就可以啦
