一、使用JAVA_SWT编写登陆界面（不含数据库,登陆按钮未处理）

一、为了进行SWT应用开发，你需要把SWT库添加到类路径（classpath）上，并设置必要的环境变量。 　　

首先，安装及配置swt+design
1.1 下载并解压Designer_v6.9.5_for_Eclipse3.5.zip，把features和plugins覆盖到eclipse下同名文档，并把configuration文件夹下的除config.ini外的文件全部删除。
1.2 打开WindowBuilderKeygen.exe程序，填写正确网卡物理地址和版本号后，点击OK，得到序列号及注册码。
1.3 打开Eclipse，在主菜单下选择window=>Preferences=>Designer=>License=>Registration and Activation，输入序列号与注册后，点下一步按要求填写完成（Name中间有空格），最后OK（如下图）。
1.4 取消Automatically activate when possible选项。



然后。你要在ECLIPSE_HOM=》Eeclipse=》plugins文件夹下找到org.eclipse.swt.win32.win32.x86_3.3.0.v3346.jar库文件。注意这里的“org.eclipse.swt.win32.win32.x86_3.3.0.v3346.jar”是和Eclipse的版本有关的。实在找不到你就用文件搜索功能吧。然后依次打开下面窗口Project-〉Properies-〉JavaBuildPath-〉Libraries-〉Add Variable -〉 Eclipse Home -〉Extend将org.eclipse.swt.win32.win32.x86_3.3.0.v3346.jar文件加到类路径中。

二、拖拉控件，输入代码(界面如下)



功能说明：
1、限制文本框只能输入小写字母和数字
2、限制文本框字符个数为8位
3、实现退出按钮功能
4、禁止拖动，修改界面大小
5、实现CANVAS控件内图片按比例缩放显示并响应鼠标释放事件

import org.eclipse.swt.SWT;
import org.eclipse.swt.events.KeyAdapter;
import org.eclipse.swt.events.KeyEvent;
import org.eclipse.swt.events.MouseAdapter;
import org.eclipse.swt.events.MouseEvent;
import org.eclipse.swt.events.MouseMoveListener;
import org.eclipse.swt.events.PaintEvent;
import org.eclipse.swt.events.PaintListener;
import org.eclipse.swt.events.SelectionAdapter;
import org.eclipse.swt.events.SelectionEvent;
import org.eclipse.swt.graphics.Image;
import org.eclipse.swt.graphics.ImageData;
import org.eclipse.swt.graphics.Rectangle;
import org.eclipse.swt.widgets.Button;
import org.eclipse.swt.widgets.Canvas;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Label;
import org.eclipse.swt.widgets.MessageBox;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.swt.widgets.Text;
import com.swtdesigner.SWTResourceManager;
public class test {
private Text Text_password;
private Text Text_account;
protected Shell shell;
/**
* Launch the application
*
* @param args
*/
public static void main(String[] args) {
try {
test window = new test();
window.open();
} catch (Exception e) {
e.printStackTrace();
}
}
/**
* Open the window
*/
public void open() {
final Display display = Display.getDefault();
createContents();
shell.open();
shell.layout();
while (!shell.isDisposed()) {
if (!display.readAndDispatch())
display.sleep();
}
display.dispose();
}
/**
* Create contents of the window
*/
protected void createContents() {
shell = new Shell(SWT.NO_TRIM);
shell.addMouseMoveListener(new MouseMoveListener() {
public void mouseMove(final MouseEvent arg0) {
MessageBox mb = new MessageBox(shell, SWT.ICON_QUESTION
| SWT.OK | SWT.CANCEL);
mb.setText("提示");
mb.setMessage("确定要关闭吗？");
}
});
shell.setSize(360, 196);
// 取屏幕大小
Rectangle src_area = Display.getDefault().getClientArea();
// 使窗口居中显示
shell.setLocation((src_area.width - 360) / 2,
(src_area.height - 196) / 2);
// 创建"帐号"标签
final Label Lab_account = new Label(shell, SWT.CENTER);
Lab_account.setAlignment(SWT.CENTER);
Lab_account.setForeground(Display.getCurrent().getSystemColor(
SWT.COLOR_BLACK));
Lab_account.setFont(SWTResourceManager.getFont("", 12, SWT.NONE));
Lab_account.setText("帐号：");
Lab_account.setBounds(81, 42, 48, 25);
// 创建"密码"标签
final Label Lab_password = new Label(shell, SWT.CENTER);
Lab_password.setBounds(80, 82, 48, 25);
Lab_password.setFont(SWTResourceManager.getFont("", 12, SWT.NONE));
Lab_password.setText("密码：");
// 创建"帐号"文本框
Text_account = new Text(shell, SWT.BORDER);
//限制只能输入8个字符
Text_account.setTextLimit(8);
Text_account.setToolTipText("只允许输入数字以及小写字母");
// 限制输入字符
Text_account.addKeyListener(new KeyAdapter() {
public void keyPressed(final KeyEvent e) {
if (!CheckTextData(e.character))
e.doit = false;
}
});
Text_account.setFont(SWTResourceManager.getFont("", 12, SWT.NONE));
Text_account.setBounds(138, 40, 111, 25);
// 创建"密码"文本框
Text_password = new Text(shell, SWT.BORDER | SWT.PASSWORD);
//限制输入8个字符
Text_password.setTextLimit(8);
Text_password.setToolTipText("只允许输入数字以及小写字母");
// 限制输入字符
Text_password.addKeyListener(new KeyAdapter() {
public void keyPressed(final KeyEvent e) {
if (!CheckTextData(e.character))
e.doit = false;
}
});
Text_password.setFont(SWTResourceManager.getFont("", 12, SWT.NONE));
Text_password.setBounds(138, 82, 111, 25);
// 创建"登陆"按钮
final Button Btn_login = new Button(shell, SWT.NONE);
//设置缺省按钮
shell.setDefaultButton(Btn_login);
Btn_login.setText("登陆");
Btn_login.setBounds(105, 135, 48, 22);
// 创建"退出"按钮
final Button Btn_quit = new Button(shell, SWT.NONE);
// “退出”按钮事件
Btn_quit.addSelectionListener(new SelectionAdapter() {
public void widgetSelected(final SelectionEvent e) {
MessageBox mb = new MessageBox(shell, SWT.ICON_QUESTION
| SWT.OK | SWT.CANCEL);
mb.setText("提示");
mb.setMessage("确定要关闭吗？");
int rc = mb.open();
if (e.doit == (rc == SWT.OK)) {
// 做窗口关闭事件
shell.close();
} else {
// 什么也不做
}
}
});
Btn_quit.setText("退出");
Btn_quit.setBounds(200, 135, 48, 22);
// 创建配置图片
final Canvas canvas = new Canvas(shell, SWT.NONE);
canvas.setBounds(265, 108, 79, 71);
Rectangle rect_can = canvas.getBounds();
ImageData Data_img = new ImageData("Res//Setting.png").scaledTo(
rect_can.width, rect_can.height);
final Image myImage = new Image(Display.getDefault(), Data_img);
canvas.addPaintListener(new PaintListener() {
public void paintControl(PaintEvent e) {
e.gc.drawImage(myImage, 0, 0);
}
});
/**
* Canvas获得焦点响应 canvas.addKeyListener(new KeyAdapter() { public void
* keyPressed(final KeyEvent e) {
* System.out.println("这事件不知为何，为下面事件做铺垫"); } });
* canvas.addFocusListener(new FocusAdapter() { public void
* focusGained(final FocusEvent e) { System.out.println("sdfsd"); } });
*/
// CANVAS中鼠标事件
canvas.addMouseListener(new MouseAdapter() {
//鼠标释放
public void mouseUp(final MouseEvent e) {
System.out.println("Up");
}
});
}
// 文本框输入内容检查,只允许小写字母和数字
public boolean CheckTextData(char ch) {
if (Character.isDigit(ch) || ch == '/b' || Character.isLowerCase(ch)) {
return true;
}
return false;
}
}