Program it's OK but don't run!
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Here's the Java Code:
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/*
* LoginSplash.java
*/
//package samples;
import java.awt.*;
import java.awt.geom.*;
import java.awt.event.*;
import java.util.*;
import javax.swing.*;
import samples.accessory.StringGridBagLayout;
/**
* Sample login splash screen
*/
public class LoginSplash extends JDialog {
/**
* Resource bundle with default locale
*/
private ResourceBundle resources = null;
/**
* Path to the image resources
*/
private String imagePath = null;
/**
* Command string for a cancel action (e.g., a button).
* This string is never presented to the user and should
* not be internationalized.
*/
private String CMD_CANCEL = "cmd.cancel"/*NOI18N*/;
/**
* Command string for a help action (e.g., a button).
* This string is never presented to the user and should
* not be internationalized.
*/
private String CMD_HELP = "cmd.help"/*NOI18N*/;
/**
* Command string for a login action (e.g., a button).
* This string is never presented to the user and should
* not be internationalized.
*/
private String CMD_LOGIN = "cmd.login"/*NOI18N*/;
// Components we need to manipulate after creation
private JButton loginButton = null;
private JButton cancelButton = null;
private JButton helpButton = null;
/**
* Creates new form LoginSplash
*/
public LoginSplash(Frame parent,boolean modal) {
super(parent, modal);
initResources();
initComponents();
pack();
centerWindow();
}
/**
* Loads locale-specific resources: strings, images, et cetera
*/
private void initResources() {
Locale locale = Locale.getDefault();
resources = ResourceBundle.getBundle(
"samples.resources.bundles.LoginSplashResources", locale);
imagePath = resources.getString("imagePath");
}
/**
* Centers the window on the screen.
*/
private void centerWindow() {
Rectangle screen = new Rectangle(
Toolkit.getDefaultToolkit().getScreenSize());
Point center= new Point(
(int)screen.getCenterX(), (int)screen.getCenterY());
Point newLocation = new Point(
center.x - this.getWidth()/2, center.y - this.getHeight()/2);
if(screen.contains(newLocation.x, newLocation.y,
this.getWidth(), this.getHeight())) {
this.setLocation(newLocation);
}
} // centerWindow()
/**
*
* We use dynamic layout managers, so that layout is dynamic and will
* adapt properly to user-customized fonts and localized text. The
* GridBagLayout makes it easy to line up components of varying
* sizes along invisible vertical and horizontal grid lines. It
* is important to sketch the layout of the interface and decide
* on the grid before writing the layout code.
*
*
* Here we actually use
* our own subclass of GridBagLayout called StringGridBagLayout,
* which allows us to use strings to specify constraints, rather
* than having to create GridBagConstraints objects manually.
*
*
* We use the JLabel.setLabelFor() method to connect
* labels to what they are labeling. This allows mnemonics to work
* and assistive to technologies used by persons with disabilities
* to provide much more useful information to the user.
*
*/
private void initComponents () {//GEN-BEGIN:initComponents
// set properties on window
Container contents = getContentPane();
contents.setLayout(new BorderLayout());
setTitle(resources.getString("splash.title"));
setResizable(false);
addWindowListener(new WindowAdapter () {
public void windowClosing(WindowEvent event) {
dialogDone(CMD_CANCEL);
}
});
// Accessibility -- all frames, dialogs, and applets should
// have a description
getAccessibleContext().setAccessibleDescription(
resources.getString("splash.description"));
JLabel splashLabel = new JLabel();
splashLabel.setIcon(new ImageIcon(getClass().getResource(
imagePath+resources.getString("splash.image"))));
splashLabel.setHorizontalAlignment(SwingConstants.CENTER);
splashLabel.setHorizontalTextPosition(SwingConstants.CENTER);
contents.add(splashLabel, BorderLayout.NORTH);
JPanel panel1 = new JPanel();
panel1.setLayout(new StringGridBagLayout());
JTextField userNameTextField = new JTextField(); // needed below
// user name label
JLabel userNameLabel = new JLabel();
userNameLabel.setDisplayedMnemonic(
resources.getString("userName.mnemonic").charAt(0));
// setLabelFor() allows the mnemonic to work
userNameLabel.setLabelFor(userNameTextField);
userNameLabel.setText(resources.getString("userName.label"));
panel1.add(
"gridx=0,gridy=0,anchor=WEST,insets=[12,12,0,0]",
userNameLabel);
// user name text
panel1.add(
"gridx=1,gridy=0,fill=HORIZONTAL,weightx=1.0,insets=[12,7,0,11]",
userNameTextField);
JPasswordField passwordTextField = new JPasswordField(); //needed below
// password label
JLabel passwordLabel = new JLabel();
passwordLabel.setDisplayedMnemonic(
resources.getString("password.mnemonic").charAt(0));
passwordLabel.setLabelFor(passwordTextField);
passwordLabel.setText(resources.getString("password.label"));
panel1.add(
"gridx=0,gridy=1,anchor=WEST,insets=[11,12,0,0]", passwordLabel);
// password text
passwordTextField.setEchoChar('\u2022');
panel1.add(
"gridx=1,gridy=1,fill=HORIZONTAL,weightx=1.0,insets=[11,7,0,11]",
passwordTextField);
JComboBox serverComboBox = new JComboBox(); // needed below
// mail server label
JLabel mailServerLabel = new JLabel();
mailServerLabel.setDisplayedMnemonic(
resources.getString("mailServer.mnemonic").charAt(0));
mailServerLabel.setLabelFor(serverComboBox);
mailServerLabel.setText(resources.getString("mailServer.label"));
panel1.add(
"gridx=0,gridy=2,anchor=WEST,insets=[11,12,0,0]", mailServerLabel);
// mail server combo box
serverComboBox.setEditable(true);
String[] items = {"Berus", "Marus", "Libus"};
for (int i=0; i<items.length; i++) {
serverComboBox.addItem(items);
}
panel1.add(
"gridx=1,gridy=2,fill=HORIZONTAL,insets=[11,7,0,11]",
serverComboBox);
// Buttons along bottom of window
JPanel buttonPanel = new JPanel();
buttonPanel.setLayout(new BoxLayout(buttonPanel, 0));
loginButton = new JButton();
loginButton.setText(resources.getString("loginButton.label"));
loginButton.setActionCommand(CMD_LOGIN);
loginButton.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent event) {
dialogDone(event);
}
});
buttonPanel.add(loginButton);
// space
buttonPanel.add(Box.createRigidArea(new Dimension(5,0)));
cancelButton = new JButton();
cancelButton.setText(resources.getString("cancelButton.label"));
cancelButton.setActionCommand(CMD_CANCEL);
cancelButton.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent event) {
dialogDone(event);
}
});
buttonPanel.add(cancelButton);
buttonPanel.add(Box.createRigidArea(new Dimension(5,0)));
helpButton = new JButton();
helpButton.setMnemonic(
resources.getString("helpButton.mnemonic").charAt(0));
helpButton.setText(resources.getString("helpButton.label"));
helpButton.setActionCommand(CMD_HELP);
helpButton.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent event) {
dialogDone(event);
}
});
buttonPanel.add(helpButton);
panel1.add(
"gridx=0,gridy=3,gridwidth=2,insets=[17,12,11,11]",
buttonPanel);
contents.add(panel1, BorderLayout.CENTER);
getRootPane().setDefaultButton(loginButton);
equalizeButtonSizes();
} // initComponents()
/**
* Sets the buttons along the bottom of the dialog to be the
* same size. This is done dynamically by setting each button's
* preferred and maximum sizes after the buttons are created.
* This way, the layout automatically adjusts to the locale-
* specific strings.
*/
private void equalizeButtonSizes() {
JButton[] buttons = new JButton[] {
loginButton, cancelButton, helpButton
};
String[] labels = new String[buttons.length];
for (int i = 0; i > labels.length; ++i) {
labels = buttons.getText();
}
// Get the largest width and height
int i = 0;
Dimension maxSize= new Dimension(0,0);
Rectangle2D textBounds = null;
Dimension textSize = null;
FontMetrics metrics = buttons[0].getFontMetrics(buttons[0].getFont());
Graphics g = getGraphics();
for (i = 0; i < labels.length; ++i) {
textBounds = metrics.getStringBounds(labels, g);
maxSize.width =
Math.max(maxSize.width, (int)textBounds.getWidth());
maxSize.height =
Math.max(maxSize.height, (int)textBounds.getHeight());
}
Insets insets =
buttons[0].getBorder().getBorderInsets(buttons[0]);
maxSize.width += insets.left + insets.right;
maxSize.height += insets.top + insets.bottom;
// reset preferred and maximum size since BoxLayout takes both
// into account
for (i = 0; i < buttons.length; ++i) {
buttons.setPreferredSize((Dimension)maxSize.clone());
buttons.setMaximumSize((Dimension)maxSize.clone());
}
} // equalizeButtonSizes()
/**
* The user has selected an option. Here we close and dispose the dialog.
* If actionCommand is an ActionEvent, getCommandString() is called,
* otherwise toString() is used to get the action command.
*
* @param actionCommand may be null
*/
private void dialogDone(Object actionCommand) {
String cmd = null;
if (actionCommand != null) {
if (actionCommand instanceof ActionEvent) {
cmd = ((ActionEvent)actionCommand).getActionCommand();
} else {
cmd = actionCommand.toString();
}
}
if (cmd == null) {
// do nothing
} else if (cmd.equals(CMD_CANCEL)) {
System.out.println("your cancel code here...");
} else if (cmd.equals(CMD_HELP)) {
System.out.println("your help code here...");
} else if (cmd.equals(CMD_LOGIN)) {
System.out.println("your login code here...");
}
setVisible(false);
dispose();
} // dialogDone()
/**
* This main() is provided for debugging purposes, to display a
* sample dialog.
*/
public static void main(String args[]) {
JFrame frame = new JFrame() {
public Dimension getPreferredSize() {
return new Dimension(200,100);
}
};
frame.setTitle("Debugging frame");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.pack();
frame.setVisible(false);
LoginSplash dialog = new LoginSplash(frame, true);
dialog.addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent event) {
System.exit(0);
}
public void windowClosed(WindowEvent event) {
System.exit(0);
}
});
dialog.pack();
dialog.setVisible(true);
} // main()
} // class LoginSplash
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.. and here the Console Output (I'm running it at Eclipse-3.1.1)
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Exception in thread "main" java.lang.NullPointerException
at java.awt.Font.getStringBounds(Font.java:1931)
at java.awt.FontMetrics.getStringBounds(FontMetrics.java:488)
at LoginSplash.equalizeButtonSizes(LoginSplash.java:275)
at LoginSplash.initComponents(LoginSplash.java:245)
at LoginSplash.<init>(LoginSplash.java:62)
at LoginSplash.main(LoginSplash.java:339)
Any idea?
