在我的FlashCardPanel类中，我有一个子面板LabelPanel，带有Grid Bag Layout。它由带有编辑按钮的构造函数，用于“翻转”卡片的按钮和用于显示术语/定义的标签组成。我的问题是，每次单击“翻转”按钮以显示我的术语的定义时，翻转按钮将改变大小，通常与定义的长度相匹配。
问题的图像 http://postimg.org/gallery/ymww3axq/
import java.awt.BorderLayout;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.GridLayout;
import java.awt.Insets;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.BoxLayout;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
public class FlashCardPanel extends JPanel{
private String term;
private String definition;
// shows the current text whether it is a term or definition
private JLabel currentLabel;
private static String NO_CARDS = "This set is empty";
//current card being displayed
private FlashCard currentCard;
//new card that is added to the deck
private FlashCard newCard;
// true = term is showing; false = definition is showing
private boolean termShowing = true;
private AddNewCard frame;
private CardSet cardSet;
private int cardIndex = 0;
private ButtonPanel bPanel;
private LabelPanel lPanel;
private static JButton flipButton;
private static JButton nextButton;
private static JButton prevButton;
private static JButton addCard;
private static JButton deleteCard;
private static JButton editButton;
public FlashCardPanel(CardSet cardSet) {
this.cardSet = cardSet;
this.setLayout(new BoxLayout(this, BoxLayout.PAGE_AXIS));
term = cardSet.get(0).getTerm();
definition = cardSet.get(0).getDefintion();
currentCard = cardSet.get(0);
createButtons();
lPanel = new LabelPanel();
bPanel = new ButtonPanel();
add(lPanel);
add(bPanel);
}
public FlashCardPanel() {
this.setLayout(new BoxLayout(this, BoxLayout.LINE_AXIS));
add(lPanel);
add(bPanel);
}
private class LabelPanel extends JPanel {
public LabelPanel() {
this.setLayout(new GridBagLayout());
GridBagConstraints c = new GridBagConstraints();
c.insets = new Insets(15,15,15,15);
currentLabel = new JLabel(term);
currentLabel.setText(cardSet.get(0).getTerm());
c.fill = GridBagConstraints.HORIZONTAL;
c.weightx = 0;
c.gridx = 0;
c.gridy = 0;
add(editButton,c);
c.fill = GridBagConstraints.HORIZONTAL;
c.ipady = 0;
c.gridwidth = 0;
c.weightx = 0;
c.gridx = 2;
c.gridy = 0;
add(flipButton,c);
c.fill = GridBagConstraints.HORIZONTAL;
c.ipady = 40;
c.weightx = 0;
c.gridwidth = 3;
c.gridx = 1;
c.gridy = 3;
add(currentLabel,c);
}
}
private class ButtonPanel extends JPanel {
public ButtonPanel() {
this.setLayout(new GridLayout(2,2));
add(prevButton);
add(nextButton);
add(addCard);
add(deleteCard);
}
}
/*
* creates buttons for the panel. Should be called before
* any subpanel is created.
*/
private void createButtons()
{
flipButton = new JButton(" Flip Card ");
flipButton.addActionListener(new ButtonListener());
flipButton.setActionCommand("1");
nextButton = new JButton(" Next Card ");
nextButton.addActionListener(new ButtonListener());
nextButton.setActionCommand("2");
prevButton = new JButton(" Previous Card ");
prevButton.addActionListener(new ButtonListener());
prevButton.setActionCommand("3");
addCard = new JButton(" Add Card ");
addCard.addActionListener(new ButtonListener());
addCard.setActionCommand("4");
deleteCard = new JButton(" Delete Card ");
deleteCard.addActionListener(new ButtonListener());
deleteCard.setActionCommand("5");
editButton = new JButton("Edit");
editButton.addActionListener(new ButtonListener());
editButton.setActionCommand("6");
}
private class ButtonListener implements ActionListener
{
@Override
public void actionPerformed(ActionEvent e) {
int action = Integer.parseInt(e.getActionCommand());
switch(action){
case 1:
flipCard();
break;
case 2:
nextCard();
break;
case 3:
previousCard();
break;
case 4:
createFrame();
break;
case 5:
deleteCard();
case 6:
createFrame(term,definition);
}
}
}
private void flipCard()
{
if (!cardSet.isEmpty()) {
if (termShowing) {
termShowing = false;
currentLabel.setText(definition);
}
else {
termShowing = true;
currentLabel.setText(term);
}
}
else {
currentLabel.setText(NO_CARDS);
term = "";
definition = "";
JOptionPane.showMessageDialog(this, "This set is empty");
}
}
private void nextCard()
{
if (!cardSet.isEmpty()) {
if (cardIndex == cardSet.size()-1)
cardIndex = 0;
else
cardIndex++;
term = cardSet.get(cardIndex).getTerm();
definition = cardSet.get(cardIndex).getDefintion();
if(termShowing)
currentLabel.setText(term);
else
currentLabel.setText(definition);
currentCard = cardSet.get(cardIndex);
}
else JOptionPane.showMessageDialog(this, "This set is empty");
}
private void previousCard()
{
if (!cardSet.isEmpty()) {
if (cardIndex == 0)
cardIndex = cardSet.size()-1;
else
cardIndex--;
term = cardSet.get(cardIndex).getTerm();
definition = cardSet.get(cardIndex).getDefintion();
if(termShowing)
currentLabel.setText(term);
else
currentLabel.setText(definition);
currentCard = cardSet.get(cardIndex);
}
else JOptionPane.showMessageDialog(this, "This set is empty");
}
/*
* adding a card
*/
private void createFrame() {
frame = new AddNewCard(100,100,this);
}
/*
* editing an existing card
*/
private void createFrame(String t, String d)
{
frame = new AddNewCard(100,100,this,t,d);
}
public void addNewCard(String t, String d) {
newCard = new FlashCard(t,d);
cardSet.add(newCard);
if (cardSet.isEmpty()) currentLabel.setText(newCard.getTerm());
}
public void editCard(String t, String d) {
currentCard.setTerm(t);
currentCard.setDefinition(d);
if (termShowing) currentLabel.setText(t);
else currentLabel.setText(d);
}
/*
* Deletes current card on display
*/
private void deleteCard()
{
if (!cardSet.isEmpty()) {
// if on the last card of the set
if (cardIndex == cardSet.size()-1) cardIndex--;
cardSet.remove(currentCard);
if (!cardSet.isEmpty()) {
currentCard = cardSet.get(cardIndex);
currentLabel.setText(cardSet.get(cardIndex).getTerm());
}
else currentLabel.setText(NO_CARDS);
}
else JOptionPane.showMessageDialog(this, "This set is empty");
}
}
答案 0 :(得分：5)
您有多种选择，包括：
注意，对于将来的问题，请减少您的问题。例如，如果这是我的问题，我会创建类似下面的代码，小，自包含，可运行并演示问题：
import java.awt.Dimension;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.Insets;
import java.awt.event.ActionEvent;
import javax.swing.*;
public class FlashCardPanel2 extends JPanel {
private static final long serialVersionUID = 1L;
private static final int PREF_W = 400;
private static final int PREF_H = PREF_W;
private JLabel currentLabel;
private String term = "Term";
private String definition = "Definition: This will be a very long String to "
+ "illustrate the problem that you are having, and to try to help you get "
+ "a solution";
private JButton editButton = new JButton("Edit");
private JButton flipButton = new JButton(new FlipAction("Flip"));
public FlashCardPanel2() {
this.setLayout(new GridBagLayout());
GridBagConstraints c = new GridBagConstraints();
c.insets = new Insets(15, 15, 15, 15);
currentLabel = new JLabel(term);
c.fill = GridBagConstraints.HORIZONTAL;
c.weightx = 0;
c.gridx = 0;
c.gridy = 0;
add(editButton, c);
c.fill = GridBagConstraints.HORIZONTAL;
c.ipady = 0;
c.gridwidth = 0;
c.weightx = 0;
c.gridx = 2;
c.gridy = 0;
add(flipButton, c);
c.fill = GridBagConstraints.HORIZONTAL;
c.ipady = 40;
c.weightx = 0;
c.gridwidth = 3;
c.gridx = 1;
c.gridy = 3;
add(currentLabel, c);
}
@Override
public Dimension getPreferredSize() {
if (isPreferredSizeSet()) {
return super.getPreferredSize();
}
return new Dimension(PREF_W, PREF_H);
}
private class FlipAction extends AbstractAction {
public FlipAction(String name) {
super(name);
int mnemonic = (int) name.charAt(0);
putValue(MNEMONIC_KEY, mnemonic);
}
@Override
public void actionPerformed(ActionEvent e) {
String text = currentLabel.getText();
text = (text.equals(term)) ? definition : term;
currentLabel.setText(text);
}
}
private static void createAndShowGui() {
JFrame frame = new JFrame("FlashCardPanel2");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(new FlashCardPanel2());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGui();
}
});
}
}
这是CardLayout和GridLayout以及BorderLayout的潜在解决方案：
import java.awt.BorderLayout;
import java.awt.CardLayout;
import java.awt.Component;
import java.awt.Dimension;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.GridLayout;
import java.awt.Insets;
import java.awt.event.ActionEvent;
import javax.swing.*;
public class FlashCardPanel3 extends JPanel {
private static final long serialVersionUID = 1L;
private static final String CURRENT_LABEL = "current label";
private static final String DEFINITION = "definition";
private JLabel currentLabel;
private JTextArea currentDefinitionArea = new JTextArea(6, 20);
private CardLayout cardLayout = new CardLayout();
private JPanel cardHolder = new JPanel(cardLayout);
private String term = "Term";
private String definition = "Definition: This will be a very long String to "
+ "illustrate the problem that you are having, and to try to help you get "
+ "a solution";
private JButton editButton = new JButton("Edit");
private JButton flipButton = new JButton(new FlipAction("Flip"));
public FlashCardPanel3() {
currentDefinitionArea.setOpaque(false);
currentDefinitionArea.setText(definition);
currentDefinitionArea.setWrapStyleWord(true);
currentDefinitionArea.setLineWrap(true);
currentDefinitionArea.setEditable(false);
currentDefinitionArea.setFocusable(false);
currentLabel = new JLabel(term, SwingConstants.CENTER);
cardHolder.add(currentLabel, CURRENT_LABEL);
cardHolder.add(new JScrollPane(currentDefinitionArea), DEFINITION);
JPanel buttonPanel = new JPanel(new GridLayout(1, 2, 5, 0));
buttonPanel.add(editButton);
buttonPanel.add(flipButton);
setBorder(BorderFactory.createEmptyBorder(5, 5, 5, 5));
setLayout(new BorderLayout(5, 5));
add(buttonPanel, BorderLayout.PAGE_START);
add(cardHolder);
}
private class FlipAction extends AbstractAction {
public FlipAction(String name) {
super(name);
int mnemonic = (int) name.charAt(0);
putValue(MNEMONIC_KEY, mnemonic);
}
@Override
public void actionPerformed(ActionEvent e) {
// String text = currentLabel.getText();
// text = (text.equals(term)) ? definition : term;
// currentLabel.setText(text);
cardLayout.next(cardHolder);
}
}
private static void createAndShowGui() {
JFrame frame = new JFrame("FlashCardPanel2");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(new FlashCardPanel3());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGui();
}
});
}
}