从单独的 JForm 访问 JComboBox 数据
Accessing JComboBox data from separate JForm
我花了一些时间浏览 Stack Overflow 和互联网寻找我的问题的答案，但我发现所有答案都难以理解，我不确定它们是否与我的问题有关，所以我决定在适当的情况下需要帮助。
我正在创建一个程序，它将根据输入的特定类型的图形给出一系列解决方案。我真诚地努力在第一个 JFrame 中从我的 JComboBox 中获取数据，并在第二个中显示它。
我有两个 classes，GraphEquationSolverGUI 和 DefineEquation。我正在使用 Netbeans IDE 并且 GraphEquationSolverGUI 是我的 "project."
GraphEquationSolverGUI:
private void graphSelectionActionPerformed(java.awt.event.ActionEvent evt) {
String graphSelectionGUI = (String)graphSelection.getSelectedItem();
//graphSelectedTextField.setText(graphSelectionGUI);
DefineEquation graphSelectedObj = new DefineEquation(graphSelectionGUI);
graphSelectedObj.addItem(graphSelectionGUI);
这是 JComboBox，我希望选择在其中将数据发送到另一个 class。 JComboBox 称为 graphSelection。您会注意到注释文本是我将 JTextField 设置为 JComboBox 的值，它在这个 JForm 内部，我自己用它来测试以确保数据输入正确，它可以工作并且我可以显示数据在同一个 JFrame 中。下面的其他代码是我尝试创建一个对象并通过它传递数据，我对对象有点生疏，因为我已经有一段时间没有使用它们了，如果我让你哭了，抱歉。
定义方程：
public DefineEquation(String graphSelected) {
this.graphSelected = graphSelected;
} //If anyone cares here is my constructor for the object
public void addItem(String graphSelectedString1){
DefineEquation graphSelectedObj = new DefineEquation(graphSelected);
String graphSelectedStringMAIN = graphSelectedString1.toString();
selectedGraph.setText(graphSelectedStringMAIN);
}
以上是我创建的将数据添加到名为 selectedGraph 的 JTextField 的方法。您会注意到我有 graphSelectedString1 和 graphSelectedStringMAIN，我在其中将 String 转换为显然多余的 String。我这样做是为了以防万一，它是多余的，抱歉让你畏缩了。
我知道这可能很难理解，您可能会发现很难理解我的问题。简单地说，我如何将数据从一个 JFrame JComboBox 传递到另一个 JFrame 中的 JTextField？我会使用对象吗？如果可以的话，请尝试引导我完成它，我很困惑。如果你想通读所有内容，我会在下面粘贴我的所有代码。
GraphEquationSolverGUI:
/*
* To change this license header, choose License Headers in Project Properties.
* To change this template file, choose Tools | Templates
* and open the template in the editor.
*/
package GUI;
/**
*
* @author MatthewAlanTroutman
*/
public class GraphEquationSolverGUI extends javax.swing.JFrame {
/**
* Creates new form GraphEquationSolverGUI
*/
public GraphEquationSolverGUI() {
initComponents();
}
/**
* This method is called from within the constructor to initialize the form.
* WARNING: Do NOT modify this code. The content of this method is always
* regenerated by the Form Editor.
*/
@SuppressWarnings("unchecked")
// <editor-fold defaultstate="collapsed" desc="Generated Code">
private void initComponents() {
jSpinner1 = new javax.swing.JSpinner();
welcome = new javax.swing.JLabel();
programDescription = new javax.swing.JLabel();
graphsOffered = new javax.swing.JLabel();
linear = new javax.swing.JLabel();
bilinear = new javax.swing.JLabel();
quadratic = new javax.swing.JLabel();
cubic = new javax.swing.JLabel();
exponential = new javax.swing.JLabel();
graphSelectionText = new javax.swing.JLabel();
graphSelection = new javax.swing.JComboBox();
help = new javax.swing.JButton();
close = new javax.swing.JButton();
next = new javax.swing.JButton();
graphSelectedTextField = new javax.swing.JTextField();
graphSelectedLabel = new javax.swing.JLabel();
setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
setTitle("GraphEquationSolver");
setBackground(new java.awt.Color(255, 255, 255));
welcome.setFont(new java.awt.Font("Lucida Grande", 0, 48)); // NOI18N
welcome.setHorizontalAlignment(javax.swing.SwingConstants.CENTER);
welcome.setText("Welcome");
welcome.setPreferredSize(new java.awt.Dimension(800, 100));
programDescription.setFont(new java.awt.Font("Lucida Grande", 0, 14)); // NOI18N
programDescription.setText("You can use this program to find a variety of solutions for different types of graphs, please select a graph to begin");
programDescription.setPreferredSize(new java.awt.Dimension(800, 75));
graphsOffered.setFont(new java.awt.Font("Lucida Grande", 0, 18)); // NOI18N
graphsOffered.setText("Graphs we offer:");
linear.setFont(new java.awt.Font("Lucida Grande", 0, 14)); // NOI18N
linear.setText("- Linear");
bilinear.setFont(new java.awt.Font("Lucida Grande", 0, 14)); // NOI18N
bilinear.setText("- Bilinear");
quadratic.setFont(new java.awt.Font("Lucida Grande", 0, 14)); // NOI18N
quadratic.setText("- Quadratic");
cubic.setFont(new java.awt.Font("Lucida Grande", 0, 14)); // NOI18N
cubic.setText("- Cubic");
exponential.setFont(new java.awt.Font("Lucida Grande", 0, 14)); // NOI18N
exponential.setText("- Exponential");
graphSelectionText.setFont(new java.awt.Font("Lucida Grande", 0, 18)); // NOI18N
graphSelectionText.setText("Please select your graph");
graphSelection.setModel(new javax.swing.DefaultComboBoxModel(new String[] { "Linear", "Bilinear", "Quadratic", "Cubic", "Exponential" }));
graphSelection.setToolTipText("");
graphSelection.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
graphSelectionActionPerformed(evt);
}
});
help.setFont(new java.awt.Font("Lucida Grande", 0, 48)); // NOI18N
help.setText("Help");
close.setFont(new java.awt.Font("Lucida Grande", 0, 48)); // NOI18N
close.setText("Close");
close.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
closeActionPerformed(evt);
}
});
next.setFont(new java.awt.Font("Lucida Grande", 0, 48)); // NOI18N
next.setText("Next");
next.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
nextActionPerformed(evt);
}
});
graphSelectedTextField.setEditable(false);
graphSelectedLabel.setFont(new java.awt.Font("Lucida Grande", 0, 18)); // NOI18N
graphSelectedLabel.setText("Graph Selected");
javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
getContentPane().setLayout(layout);
layout.setHorizontalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
.addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
.addComponent(welcome, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
.addGap(240, 240, 240))
.addGroup(layout.createSequentialGroup()
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addGap(240, 240, 240)
.addComponent(programDescription, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE))
.addGroup(layout.createSequentialGroup()
.addGap(184, 184, 184)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addComponent(exponential)
.addGroup(layout.createSequentialGroup()
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addComponent(graphsOffered)
.addComponent(linear)
.addComponent(bilinear)
.addComponent(quadratic)
.addComponent(cubic))
.addGap(311, 311, 311)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING, false)
.addComponent(graphSelectionText, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
.addComponent(graphSelection, 0, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
.addComponent(graphSelectedTextField)
.addComponent(graphSelectedLabel, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)))))
.addGroup(layout.createSequentialGroup()
.addGap(231, 231, 231)
.addComponent(help, javax.swing.GroupLayout.PREFERRED_SIZE, 255, javax.swing.GroupLayout.PREFERRED_SIZE)
.addGap(18, 18, 18)
.addComponent(close, javax.swing.GroupLayout.PREFERRED_SIZE, 255, javax.swing.GroupLayout.PREFERRED_SIZE)
.addGap(18, 18, 18)
.addComponent(next, javax.swing.GroupLayout.PREFERRED_SIZE, 255, javax.swing.GroupLayout.PREFERRED_SIZE)))
.addContainerGap(240, Short.MAX_VALUE))
);
layout.setVerticalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addGap(34, 34, 34)
.addComponent(welcome, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE)
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
.addComponent(programDescription, javax.swing.GroupLayout.PREFERRED_SIZE, 27, javax.swing.GroupLayout.PREFERRED_SIZE)
.addGap(73, 73, 73)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
.addComponent(graphsOffered)
.addComponent(graphSelectionText))
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
.addComponent(graphSelection, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
.addComponent(linear)
.addComponent(graphSelectedLabel))
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.TRAILING)
.addGroup(layout.createSequentialGroup()
.addComponent(bilinear)
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
.addComponent(quadratic))
.addComponent(graphSelectedTextField, javax.swing.GroupLayout.PREFERRED_SIZE, 28, javax.swing.GroupLayout.PREFERRED_SIZE))
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
.addComponent(cubic)
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
.addComponent(exponential)
.addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE))
.addGroup(layout.createSequentialGroup()
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, 219, Short.MAX_VALUE)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
.addComponent(help, javax.swing.GroupLayout.PREFERRED_SIZE, 87, javax.swing.GroupLayout.PREFERRED_SIZE)
.addComponent(close, javax.swing.GroupLayout.PREFERRED_SIZE, 87, javax.swing.GroupLayout.PREFERRED_SIZE)
.addComponent(next, javax.swing.GroupLayout.PREFERRED_SIZE, 87, javax.swing.GroupLayout.PREFERRED_SIZE))
.addGap(169, 169, 169))))
);
graphSelection.getAccessibleContext().setAccessibleName("");
help.getAccessibleContext().setAccessibleName("help");
close.getAccessibleContext().setAccessibleName("close");
pack();
}// </editor-fold>
private void graphSelectionActionPerformed(java.awt.event.ActionEvent evt) {
String graphSelectionGUI = (String)graphSelection.getSelectedItem();
graphSelectedTextField.setText(graphSelectionGUI);
//DefineEquation graphSelectedObj = new DefineEquation(graphSelectionGUI);
//graphSelectedObj.addItem(graphSelectionGUI);
}
private void closeActionPerformed(java.awt.event.ActionEvent evt) {
System.exit(0);
}
private void nextActionPerformed(java.awt.event.ActionEvent evt) {
this.setVisible(false);
new DefineEquation().setVisible(true);
}
/**
* @param args the command line arguments
*/
public static void main(String args[]) {
/* Set the Nimbus look and feel */
//<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
/* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel.
* For details see http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html
*/
try {
for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
if ("Nimbus".equals(info.getName())) {
javax.swing.UIManager.setLookAndFeel(info.getClassName());
break;
}
}
} catch (ClassNotFoundException ex) {
java.util.logging.Logger.getLogger(GraphEquationSolverGUI.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (InstantiationException ex) {
java.util.logging.Logger.getLogger(GraphEquationSolverGUI.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (IllegalAccessException ex) {
java.util.logging.Logger.getLogger(GraphEquationSolverGUI.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (javax.swing.UnsupportedLookAndFeelException ex) {
java.util.logging.Logger.getLogger(GraphEquationSolverGUI.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
}
//</editor-fold>
/* Create and display the form */
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
new GraphEquationSolverGUI().setVisible(true);
}
});
}
// Variables declaration - do not modify
private javax.swing.JLabel bilinear;
private javax.swing.JButton close;
private javax.swing.JLabel cubic;
private javax.swing.JLabel exponential;
private javax.swing.JLabel graphSelectedLabel;
private javax.swing.JTextField graphSelectedTextField;
private javax.swing.JComboBox graphSelection;
private javax.swing.JLabel graphSelectionText;
private javax.swing.JLabel graphsOffered;
private javax.swing.JButton help;
private javax.swing.JSpinner jSpinner1;
private javax.swing.JLabel linear;
private javax.swing.JButton next;
private javax.swing.JLabel programDescription;
private javax.swing.JLabel quadratic;
private javax.swing.JLabel welcome;
// End of variables declaration
}
定义方程：
/*
* To change this license header, choose License Headers in Project Properties.
* To change this template file, choose Tools | Templates
* and open the template in the editor.
*/
package GUI;
/**
*
* @author MatthewAlanTroutman
*/
public class DefineEquation extends javax.swing.JFrame {
//public class DefineEquation extends GraphEquationSolverGUI {
public String graphSelected;
/**
* Creates new form DefineEquation
*/
public DefineEquation() {
initComponents();
}
public DefineEquation(String graphSelected) {
this.graphSelected = graphSelected;
}
/**
* This method is called from within the constructor to initialize the form.
* WARNING: Do NOT modify this code. The content of this method is always
* regenerated by the Form Editor.
*/
@SuppressWarnings("unchecked")
// <editor-fold defaultstate="collapsed" desc="Generated Code">
private void initComponents() {
selectedGraph = new javax.swing.JTextField();
setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
selectedGraph.setEditable(false);
selectedGraph.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
selectedGraphActionPerformed(evt);
}
});
javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
getContentPane().setLayout(layout);
layout.setHorizontalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addGap(435, 435, 435)
.addComponent(selectedGraph, javax.swing.GroupLayout.PREFERRED_SIZE, 249, javax.swing.GroupLayout.PREFERRED_SIZE)
.addContainerGap(596, Short.MAX_VALUE))
);
layout.setVerticalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addGap(126, 126, 126)
.addComponent(selectedGraph, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
.addContainerGap(646, Short.MAX_VALUE))
);
pack();
}// </editor-fold>
private void selectedGraphActionPerformed(java.awt.event.ActionEvent evt) {
}
public void addItem(String graphSelectedString1){
DefineEquation graphSelectedObj = new DefineEquation(graphSelected);
String graphSelectedStringMAIN = graphSelectedString1.toString();
selectedGraph.setText(graphSelectedStringMAIN);
}
/**
* @param args the command line arguments
*/
public static void main(String args[]) {
/* Set the Nimbus look and feel */
//<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
/* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel.
* For details see http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html
*/
try {
for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
if ("Nimbus".equals(info.getName())) {
javax.swing.UIManager.setLookAndFeel(info.getClassName());
break;
}
}
} catch (ClassNotFoundException ex) {
java.util.logging.Logger.getLogger(DefineEquation.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (InstantiationException ex) {
java.util.logging.Logger.getLogger(DefineEquation.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (IllegalAccessException ex) {
java.util.logging.Logger.getLogger(DefineEquation.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (javax.swing.UnsupportedLookAndFeelException ex) {
java.util.logging.Logger.getLogger(DefineEquation.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
}
//</editor-fold>
/* Create and display the form */
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
new DefineEquation().setVisible(true);
}
});
}
// Variables declaration - do not modify
private javax.swing.JTextField selectedGraph;
// End of variables declaration
}
您会注意到我尝试 "extend" 我的第一个 JFrame，但这导致第二个 JFrame "window" 以某种方式与第一个 JFrame "window."
结合
概念图：
编辑 1：这是完成它的最佳方式吗？如果是这样，我将如何移动数据？对象目前让我感到困惑，还有一些非静态和静态问题，这些问题似乎无效，因为我没有任何静态问题。如果这不是最好的方法，我该怎么办？我要睡觉了，请大家多提建议和帮助，我不仅很绝望，而且很失落。
编辑 2：我正在尝试使用 m.cekiera 的答案，请在回答之前参考他的答案，因为它可能会有帮助。
编辑 3：仍然卡住了，需要详细帮助，很抱歉这么苛刻，但我无法解决这个问题。
编辑 4：我想我找到了重大突破。我已经想出如何解决这个问题，但我真的认为我需要理解这一点。不管怎样，我有一个新的 class 和一个不同的 class 的新文本字段。我仍然有问题，我无法显示文本字段的值，但由于某种原因我可以输出相同的值。我想它更容易显示
所以这是 class SelectSolutionsQuadratic:
public void displayText(String textToSet) {
displayQuadraticEquation.setText(textToSet);
System.out.println(textToSet);
}
这是 DefineEquationQuadratic:
private void nextActionPerformed(java.awt.event.ActionEvent evt) {
this.setVisible(false);
new SelectSolutionsQuadratic().setVisible(true);
SelectSolutionsQuadratic transferMe = new SelectSolutionsQuadratic();
transferData = aQuadraticSpinner.getValue().toString() + " " + addSubQuadraticComboBox.getSelectedItem();
transferMe.displayText(transferData);
}
所以基本上我只是很困惑为什么我可以将一个值从 DefineEquationQuadratic 发送到 SelectSolutionsQuadratic，然后用 System.out.println() 输出它；但是 NOT 将文本字段设置为该值
如果您只是不想将数据发送到 DefineEquation class，您应该在 nextActionPerformed:
中使用带有 String 参数的构造函数
new DefineEquation((String)graphSelection.getSelectedItem()).setVisible(true);
而不是：
new DefineEquation().setVisible(true);
您还需要将构造函数更改为：
public DefineEquation(String graphSelected) {
this.graphSelected = graphSelected;
initComponents();
}
因为现在没有 initComponents() 它将显示空框。
最后，你需要在DefineEquationclass中setText()到JTextField，例如：
selectedGraph = new javax.swing.JTextField(graphSelected);
不要使用 addItem() 方法或重写它，因为它会创建新的 DefineEquation 对象，这是不必要的，甚至是有害的。这样在新框架中它会显示 JTextField 和所选文本。它对我有用，至少如果我正确理解了你的问题。
但是，我宁愿使用 enums 而不是普通的 String，因为它们更可靠。您的函数集是不变的，因此您可以创建例如：
public enum Functions {NONE,LINEAR,BILINEAR,QUADRIATIC,CUBIC,EXPONENTIAL;}
这将需要更改构造函数和 JComboBox 内容，但您可以在整个应用程序中使用它。你可以在需要String显示的地方调用toString()或name()，但在事件处理等中使用枚举。
我认为您还应该按照评论中的建议重新考虑对多个 JFrames 的处理方法。我也不建议这样做，但这取决于您。
祝你好运！
编辑
如果你不想在DefineEquation中更改initComponents()，你仍然可以像这样修改addItem()：
public void addItem(){
selectedGraph.setText(graphSelected);
}
但随后您在构造函数中调用 addItem()，以用所选文本填充 JTextField。
或者您可以将 graphSelected 作为方法的参数传递，如果是这样，它不必是 class 字段。
我的建议是创建两个 JPanel classes，一个保存 JComboBox，另一个显示或需要结果。假设您已经这样做并调用了第一个 class、HoldsComboBoxPanel，并且您的第二个 class 被称为 ShowSelectionPanel，那么您将为 HoldsComboBoxPanel 提供两个方法，一个是获取当前选择，一个 "getter" 方法，另一个允许外部 classes 将 ActionListener 添加到组合框。例如，简而言之，像这样：
public class HoldsComboBoxPanel extends JPanel {
public static final String NAME = "holds combobox panel";
// sample data
private static final String[] DATA = { "Monday", "Tuesday", "Wednesday",
"Thursday", "Friday" };
private JComboBox<String> comboBox = new JComboBox<>(DATA);
public HoldsComboBoxPanel() {
// add the comboBox into our class here
}
// method to add a listener
public void addComboBoxListener(ActionListener listener) {
comboBox.addActionListener(listener);
}
// getter method
public String getComboSelection() {
return (String) comboBox.getSelectedItem();
}
}
你的第二个 class，需要数据的那个将有一个 setter 方法允许外部 classes 将组合选择推入其中的能力。假设它有一个名为 displayField 的 JTextField 来显示选择，它的代码可能如下所示：
public class ShowSelectionPanel extends JPanel {
public static final String NAME = "show selection panel";
private JTextField displayField = new JTextField(10);
public ShowSelectionPanel() {
// add the displayField to the JPanel here
}
// setter method
public void setDisplayText(String text) {
displayField.setText(text);
// or do whatever else you want to do with the selection
}
}
然后您将有另一个 class 使用 CardLayout 并允许在上面的视图 JPanel 之间交换，例如称为 MainPanel。它可以使用 CardLayout 来允许您交换 JPanel，有一个 public 方法允许外部 classes 交换 "card" JPanel，并且它会同时包含 HoldsComboBoxPanel 字段和 ShowSelectionPanel 字段，并且可以通过将 ActionListener 添加到组合框来 link 它们，如下所示：
public class MainPanel extends JPanel {
private CardLayout cardLayout = new CardLayout();
private MenuPanel menuPanel = new MenuPanel();
private HoldsComboBoxPanel holdsComboBoxPanel = new HoldsComboBoxPanel();
private ShowSelectionPanel showSelectionPanel = new ShowSelectionPanel();
public MainPanel() {
// add an ActionListener to the JComboBox
holdsComboBoxPanel.addComboBoxListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
// get the combo's selected String
String selection = holdsComboBoxPanel.getComboSelection();
if (selection != null) {
// push it into showSelection
showSelectionPanel.setDisplayText(selection);
}
}
});
setLayout(cardLayout);
add(menuPanel, MenuPanel.NAME);
add(holdsComboBoxPanel, HoldsComboBoxPanel.NAME);
add(showSelectionPanel, ShowSelectionPanel.NAME);
}
// method that allows outside classes to swap views
public void showCard(String key) {
cardLayout.show(this, key);
}
}
带有一些额外代码以允许在 "cards" 中移动的整个过程看起来像这样：
import java.awt.BorderLayout;
import java.awt.CardLayout;
import java.awt.Component;
import java.awt.Container;
import java.awt.Dimension;
import java.awt.GridBagLayout;
import java.awt.GridLayout;
import java.awt.Window;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import javax.swing.AbstractAction;
import javax.swing.AbstractButton;
import javax.swing.Action;
import javax.swing.BorderFactory;
import javax.swing.JButton;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JPopupMenu;
import javax.swing.JTextField;
import javax.swing.SwingUtilities;
public class SimpleMultPanels {
private static void createAndShowGui() {
// create JFrame
JFrame frame = new JFrame("SimpleMultPanels");
frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
// add our MainPanel to the JFrame
frame.getContentPane().add(new MainPanel());
frame.pack(); // pack it
frame.setLocationByPlatform(true);
frame.setVisible(true); // show it
}
public static void main(String[] args) {
// this is for starting our Swing app on the event thread
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGui();
}
});
}
}
@SuppressWarnings("serial")
class MainPanel extends JPanel {
private CardLayout cardLayout = new CardLayout();
// the three "card" JPanels that this JPanel displays:
private MenuPanel menuPanel = new MenuPanel();
private HoldsComboBoxPanel holdsComboBoxPanel = new HoldsComboBoxPanel();
private ShowSelectionPanel showSelectionPanel = new ShowSelectionPanel();
// Actions for our JButtons
private ExitAction exitAction = new ExitAction();
private ShowAction backToMenuAction = new ShowAction(this, "Back to Menu",
MenuPanel.NAME, KeyEvent.VK_B);
private ShowAction toHoldsComboAction = new ShowAction(this, "Combo Panel",
HoldsComboBoxPanel.NAME, KeyEvent.VK_C);
private ShowAction toShowSelectionAction = new ShowAction(this,
"Show Selection", ShowSelectionPanel.NAME, KeyEvent.VK_S);
public MainPanel() {
// add an ActionListener to the JComboBox
holdsComboBoxPanel.addComboBoxListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
// get the combo's selected String
String selection = holdsComboBoxPanel.getComboSelection();
if (selection != null) {
// push it into showSelection
showSelectionPanel.setDisplayText(selection);
}
}
});
// add Actions to class to allow swapping of cards and
holdsComboBoxPanel.addButtonAction(backToMenuAction);
holdsComboBoxPanel.addButtonAction(toShowSelectionAction);
holdsComboBoxPanel.addButtonAction(exitAction); // and to exit gui
showSelectionPanel.addButtonAction(backToMenuAction);
showSelectionPanel.addButtonAction(toHoldsComboAction);
showSelectionPanel.addButtonAction(exitAction);
menuPanel.addButtonAction(toHoldsComboAction);
menuPanel.addButtonAction(toShowSelectionAction);
menuPanel.addButtonAction(exitAction);
setBorder(BorderFactory.createEmptyBorder(5, 5, 5, 5));
// set our layout
setLayout(cardLayout);
// and add our "card" JPanels
add(menuPanel, MenuPanel.NAME);
add(holdsComboBoxPanel, HoldsComboBoxPanel.NAME);
add(showSelectionPanel, ShowSelectionPanel.NAME);
}
// method that allows outside classes to swap views
public void showCard(String key) {
cardLayout.show(this, key);
}
}
@SuppressWarnings("serial")
class HoldsComboBoxPanel extends JPanel {
// constant String that will be used by the CardLayout
public static final String NAME = "holds combobox panel";
// sample data
private static final String[] DATA = { "Monday", "Tuesday", "Wednesday",
"Thursday", "Friday" };
private JComboBox<String> comboBox = new JComboBox<>(DATA);
// JPanel to hold buttons to allow moving between cards
private JPanel buttonPanel = new JPanel(new GridLayout(1, 0, 5, 0));
public HoldsComboBoxPanel() {
comboBox.setSelectedIndex(-1);
JPanel centerPanel = new JPanel();
centerPanel.add(comboBox);
setLayout(new BorderLayout());
add(centerPanel, BorderLayout.CENTER);
add(buttonPanel, BorderLayout.SOUTH);
}
// method to add a listener
public void addComboBoxListener(ActionListener listener) {
comboBox.addActionListener(listener);
}
// getter method
public String getComboSelection() {
return (String) comboBox.getSelectedItem();
}
// create a new JButton with an Action and add to buttonPanel
public void addButtonAction(Action action) {
buttonPanel.add(new JButton(action));
}
}
@SuppressWarnings("serial")
class ShowSelectionPanel extends JPanel {
public static final String NAME = "show selection panel";
private static final int PREF_W = 300;
private static final int PREF_H = PREF_W;
private JTextField displayField = new JTextField(10);
private JPanel buttonPanel = new JPanel(new GridLayout(1, 0, 5, 0));
public ShowSelectionPanel() {
displayField.setFocusable(false);
JPanel centerPanel = new JPanel();
centerPanel.add(displayField);
setLayout(new BorderLayout());
add(centerPanel, BorderLayout.CENTER);
add(buttonPanel, BorderLayout.SOUTH);
}
// code to make our GUI a little larger
@Override
public Dimension getPreferredSize() {
Dimension superSz = super.getPreferredSize();
if (isPreferredSizeSet()) {
return superSz;
}
int prefW = Math.max(superSz.width, PREF_W);
int prefH = Math.max(superSz.height, PREF_H);
return new Dimension(prefW, prefH);
}
// setter method
public void setDisplayText(String text) {
displayField.setText(text);
// or do whatever else you want to do with the selection
}
public void addButtonAction(Action action) {
buttonPanel.add(new JButton(action));
}
}
@SuppressWarnings("serial")
class MenuPanel extends JPanel {
public static final String NAME = "menu panel";
private JPanel buttonPanel = new JPanel(new GridLayout(0, 1, 0, 5));
public MenuPanel() {
setLayout(new GridBagLayout());
add(buttonPanel);
}
public void addButtonAction(Action action) {
buttonPanel.add(new JButton(action));
}
}
@SuppressWarnings("serial")
class ShowAction extends AbstractAction {
private MainPanel mainPanel;
private String key;
/**
* Abstract Action used by JButtons
* @param mainPanel: the JPanel that uses the CardLayout
* @param name: The name displayed by the button
* @param key: The key used in the CardLayout#show(String key) mehtod
* @param mnemonic: the JButton's mnemonic char
*/
public ShowAction(MainPanel mainPanel, String name, String key, int mnemonic) {
super(name);
putValue(MNEMONIC_KEY, mnemonic);
this.mainPanel = mainPanel;
this.key = key;
}
@Override
public void actionPerformed(ActionEvent e) {
// tell the mainPanel to show the card associated with the key
mainPanel.showCard(key);
}
}
// class of mine to allow disposing of a window
// It's a little complex to allow it to work with either a JButton
// or a JMenuItem
@SuppressWarnings("serial")
class ExitAction extends AbstractAction {
public ExitAction() {
super("Exit");
putValue(MNEMONIC_KEY, KeyEvent.VK_X);
}
@Override
public void actionPerformed(ActionEvent e) {
// get the button that caused this action
Object source = e.getSource();
if (source instanceof AbstractButton) {
AbstractButton exitButton = (AbstractButton) source;
// get the parent top level window
Window topWindow = SwingUtilities.getWindowAncestor(exitButton);
if (topWindow == null) { // if null, then likely in a JMenuItem
// so we have to get its jpopupmenu parent
Container parent = exitButton.getParent();
if (parent instanceof JPopupMenu) {
JPopupMenu popupMenu = (JPopupMenu) parent;
// get the invoker for the pop up menu
Component invoker = popupMenu.getInvoker();
if (invoker != null) {
// and get *its* top level window
topWindow = SwingUtilities.getWindowAncestor(invoker);
}
}
}
if (topWindow != null) {
// dispose of the top-level window
topWindow.dispose();
}
}
}
}
所以我真的很笨，创建了两个实例，其中一个我没有查看，另一个我查看但没有更改。基本上我所做的是在 graphSelectionActionPerformed 我做了：
this.graphSelectionGUI = (String)graphSelection.getSelectedItem();
然后在 nextActionPerformed 中我做了：
new DefineEquation_1(graphSelectionGUI).setVisible(true);
在此之后，在另一个 class (DefineEquation) 中，我使用我的构造函数并执行了以下操作：
public DefineEquation(String graphSelected) {
this.graphSelected = graphSelected;
initComponents();
selectedGraph.setText(graphSelected);
}
最后我泪流满面，才知道自己给你们带来了多大的麻烦，自己是多么的愚蠢，赞美主！
不好意思给大家添麻烦了，不好意思
我花了一些时间浏览 Stack Overflow 和互联网寻找我的问题的答案，但我发现所有答案都难以理解，我不确定它们是否与我的问题有关，所以我决定在适当的情况下需要帮助。
我正在创建一个程序，它将根据输入的特定类型的图形给出一系列解决方案。我真诚地努力在第一个 JFrame 中从我的 JComboBox 中获取数据，并在第二个中显示它。
我有两个 classes，GraphEquationSolverGUI 和 DefineEquation。我正在使用 Netbeans IDE 并且 GraphEquationSolverGUI 是我的 "project."
GraphEquationSolverGUI:
private void graphSelectionActionPerformed(java.awt.event.ActionEvent evt) {
String graphSelectionGUI = (String)graphSelection.getSelectedItem();
//graphSelectedTextField.setText(graphSelectionGUI);
DefineEquation graphSelectedObj = new DefineEquation(graphSelectionGUI);
graphSelectedObj.addItem(graphSelectionGUI);
这是 JComboBox，我希望选择在其中将数据发送到另一个 class。 JComboBox 称为 graphSelection。您会注意到注释文本是我将 JTextField 设置为 JComboBox 的值，它在这个 JForm 内部，我自己用它来测试以确保数据输入正确，它可以工作并且我可以显示数据在同一个 JFrame 中。下面的其他代码是我尝试创建一个对象并通过它传递数据，我对对象有点生疏，因为我已经有一段时间没有使用它们了，如果我让你哭了，抱歉。
定义方程：
public DefineEquation(String graphSelected) {
this.graphSelected = graphSelected;
} //If anyone cares here is my constructor for the object
public void addItem(String graphSelectedString1){
DefineEquation graphSelectedObj = new DefineEquation(graphSelected);
String graphSelectedStringMAIN = graphSelectedString1.toString();
selectedGraph.setText(graphSelectedStringMAIN);
}
以上是我创建的将数据添加到名为 selectedGraph 的 JTextField 的方法。您会注意到我有 graphSelectedString1 和 graphSelectedStringMAIN，我在其中将 String 转换为显然多余的 String。我这样做是为了以防万一，它是多余的，抱歉让你畏缩了。
我知道这可能很难理解，您可能会发现很难理解我的问题。简单地说，我如何将数据从一个 JFrame JComboBox 传递到另一个 JFrame 中的 JTextField？我会使用对象吗？如果可以的话，请尝试引导我完成它，我很困惑。如果你想通读所有内容，我会在下面粘贴我的所有代码。
GraphEquationSolverGUI:
/*
* To change this license header, choose License Headers in Project Properties.
* To change this template file, choose Tools | Templates
* and open the template in the editor.
*/
package GUI;
/**
*
* @author MatthewAlanTroutman
*/
public class GraphEquationSolverGUI extends javax.swing.JFrame {
/**
* Creates new form GraphEquationSolverGUI
*/
public GraphEquationSolverGUI() {
initComponents();
}
/**
* This method is called from within the constructor to initialize the form.
* WARNING: Do NOT modify this code. The content of this method is always
* regenerated by the Form Editor.
*/
@SuppressWarnings("unchecked")
// <editor-fold defaultstate="collapsed" desc="Generated Code">
private void initComponents() {
jSpinner1 = new javax.swing.JSpinner();
welcome = new javax.swing.JLabel();
programDescription = new javax.swing.JLabel();
graphsOffered = new javax.swing.JLabel();
linear = new javax.swing.JLabel();
bilinear = new javax.swing.JLabel();
quadratic = new javax.swing.JLabel();
cubic = new javax.swing.JLabel();
exponential = new javax.swing.JLabel();
graphSelectionText = new javax.swing.JLabel();
graphSelection = new javax.swing.JComboBox();
help = new javax.swing.JButton();
close = new javax.swing.JButton();
next = new javax.swing.JButton();
graphSelectedTextField = new javax.swing.JTextField();
graphSelectedLabel = new javax.swing.JLabel();
setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
setTitle("GraphEquationSolver");
setBackground(new java.awt.Color(255, 255, 255));
welcome.setFont(new java.awt.Font("Lucida Grande", 0, 48)); // NOI18N
welcome.setHorizontalAlignment(javax.swing.SwingConstants.CENTER);
welcome.setText("Welcome");
welcome.setPreferredSize(new java.awt.Dimension(800, 100));
programDescription.setFont(new java.awt.Font("Lucida Grande", 0, 14)); // NOI18N
programDescription.setText("You can use this program to find a variety of solutions for different types of graphs, please select a graph to begin");
programDescription.setPreferredSize(new java.awt.Dimension(800, 75));
graphsOffered.setFont(new java.awt.Font("Lucida Grande", 0, 18)); // NOI18N
graphsOffered.setText("Graphs we offer:");
linear.setFont(new java.awt.Font("Lucida Grande", 0, 14)); // NOI18N
linear.setText("- Linear");
bilinear.setFont(new java.awt.Font("Lucida Grande", 0, 14)); // NOI18N
bilinear.setText("- Bilinear");
quadratic.setFont(new java.awt.Font("Lucida Grande", 0, 14)); // NOI18N
quadratic.setText("- Quadratic");
cubic.setFont(new java.awt.Font("Lucida Grande", 0, 14)); // NOI18N
cubic.setText("- Cubic");
exponential.setFont(new java.awt.Font("Lucida Grande", 0, 14)); // NOI18N
exponential.setText("- Exponential");
graphSelectionText.setFont(new java.awt.Font("Lucida Grande", 0, 18)); // NOI18N
graphSelectionText.setText("Please select your graph");
graphSelection.setModel(new javax.swing.DefaultComboBoxModel(new String[] { "Linear", "Bilinear", "Quadratic", "Cubic", "Exponential" }));
graphSelection.setToolTipText("");
graphSelection.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
graphSelectionActionPerformed(evt);
}
});
help.setFont(new java.awt.Font("Lucida Grande", 0, 48)); // NOI18N
help.setText("Help");
close.setFont(new java.awt.Font("Lucida Grande", 0, 48)); // NOI18N
close.setText("Close");
close.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
closeActionPerformed(evt);
}
});
next.setFont(new java.awt.Font("Lucida Grande", 0, 48)); // NOI18N
next.setText("Next");
next.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
nextActionPerformed(evt);
}
});
graphSelectedTextField.setEditable(false);
graphSelectedLabel.setFont(new java.awt.Font("Lucida Grande", 0, 18)); // NOI18N
graphSelectedLabel.setText("Graph Selected");
javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
getContentPane().setLayout(layout);
layout.setHorizontalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
.addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
.addComponent(welcome, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
.addGap(240, 240, 240))
.addGroup(layout.createSequentialGroup()
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addGap(240, 240, 240)
.addComponent(programDescription, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE))
.addGroup(layout.createSequentialGroup()
.addGap(184, 184, 184)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addComponent(exponential)
.addGroup(layout.createSequentialGroup()
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addComponent(graphsOffered)
.addComponent(linear)
.addComponent(bilinear)
.addComponent(quadratic)
.addComponent(cubic))
.addGap(311, 311, 311)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING, false)
.addComponent(graphSelectionText, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
.addComponent(graphSelection, 0, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
.addComponent(graphSelectedTextField)
.addComponent(graphSelectedLabel, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)))))
.addGroup(layout.createSequentialGroup()
.addGap(231, 231, 231)
.addComponent(help, javax.swing.GroupLayout.PREFERRED_SIZE, 255, javax.swing.GroupLayout.PREFERRED_SIZE)
.addGap(18, 18, 18)
.addComponent(close, javax.swing.GroupLayout.PREFERRED_SIZE, 255, javax.swing.GroupLayout.PREFERRED_SIZE)
.addGap(18, 18, 18)
.addComponent(next, javax.swing.GroupLayout.PREFERRED_SIZE, 255, javax.swing.GroupLayout.PREFERRED_SIZE)))
.addContainerGap(240, Short.MAX_VALUE))
);
layout.setVerticalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addGap(34, 34, 34)
.addComponent(welcome, javax.swing.GroupLayout.PREFERRED_SIZE, 50, javax.swing.GroupLayout.PREFERRED_SIZE)
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
.addComponent(programDescription, javax.swing.GroupLayout.PREFERRED_SIZE, 27, javax.swing.GroupLayout.PREFERRED_SIZE)
.addGap(73, 73, 73)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
.addComponent(graphsOffered)
.addComponent(graphSelectionText))
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
.addComponent(graphSelection, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
.addComponent(linear)
.addComponent(graphSelectedLabel))
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.TRAILING)
.addGroup(layout.createSequentialGroup()
.addComponent(bilinear)
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
.addComponent(quadratic))
.addComponent(graphSelectedTextField, javax.swing.GroupLayout.PREFERRED_SIZE, 28, javax.swing.GroupLayout.PREFERRED_SIZE))
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
.addComponent(cubic)
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
.addComponent(exponential)
.addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE))
.addGroup(layout.createSequentialGroup()
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, 219, Short.MAX_VALUE)
.addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
.addComponent(help, javax.swing.GroupLayout.PREFERRED_SIZE, 87, javax.swing.GroupLayout.PREFERRED_SIZE)
.addComponent(close, javax.swing.GroupLayout.PREFERRED_SIZE, 87, javax.swing.GroupLayout.PREFERRED_SIZE)
.addComponent(next, javax.swing.GroupLayout.PREFERRED_SIZE, 87, javax.swing.GroupLayout.PREFERRED_SIZE))
.addGap(169, 169, 169))))
);
graphSelection.getAccessibleContext().setAccessibleName("");
help.getAccessibleContext().setAccessibleName("help");
close.getAccessibleContext().setAccessibleName("close");
pack();
}// </editor-fold>
private void graphSelectionActionPerformed(java.awt.event.ActionEvent evt) {
String graphSelectionGUI = (String)graphSelection.getSelectedItem();
graphSelectedTextField.setText(graphSelectionGUI);
//DefineEquation graphSelectedObj = new DefineEquation(graphSelectionGUI);
//graphSelectedObj.addItem(graphSelectionGUI);
}
private void closeActionPerformed(java.awt.event.ActionEvent evt) {
System.exit(0);
}
private void nextActionPerformed(java.awt.event.ActionEvent evt) {
this.setVisible(false);
new DefineEquation().setVisible(true);
}
/**
* @param args the command line arguments
*/
public static void main(String args[]) {
/* Set the Nimbus look and feel */
//<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
/* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel.
* For details see http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html
*/
try {
for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
if ("Nimbus".equals(info.getName())) {
javax.swing.UIManager.setLookAndFeel(info.getClassName());
break;
}
}
} catch (ClassNotFoundException ex) {
java.util.logging.Logger.getLogger(GraphEquationSolverGUI.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (InstantiationException ex) {
java.util.logging.Logger.getLogger(GraphEquationSolverGUI.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (IllegalAccessException ex) {
java.util.logging.Logger.getLogger(GraphEquationSolverGUI.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (javax.swing.UnsupportedLookAndFeelException ex) {
java.util.logging.Logger.getLogger(GraphEquationSolverGUI.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
}
//</editor-fold>
/* Create and display the form */
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
new GraphEquationSolverGUI().setVisible(true);
}
});
}
// Variables declaration - do not modify
private javax.swing.JLabel bilinear;
private javax.swing.JButton close;
private javax.swing.JLabel cubic;
private javax.swing.JLabel exponential;
private javax.swing.JLabel graphSelectedLabel;
private javax.swing.JTextField graphSelectedTextField;
private javax.swing.JComboBox graphSelection;
private javax.swing.JLabel graphSelectionText;
private javax.swing.JLabel graphsOffered;
private javax.swing.JButton help;
private javax.swing.JSpinner jSpinner1;
private javax.swing.JLabel linear;
private javax.swing.JButton next;
private javax.swing.JLabel programDescription;
private javax.swing.JLabel quadratic;
private javax.swing.JLabel welcome;
// End of variables declaration
}
定义方程：
/*
* To change this license header, choose License Headers in Project Properties.
* To change this template file, choose Tools | Templates
* and open the template in the editor.
*/
package GUI;
/**
*
* @author MatthewAlanTroutman
*/
public class DefineEquation extends javax.swing.JFrame {
//public class DefineEquation extends GraphEquationSolverGUI {
public String graphSelected;
/**
* Creates new form DefineEquation
*/
public DefineEquation() {
initComponents();
}
public DefineEquation(String graphSelected) {
this.graphSelected = graphSelected;
}
/**
* This method is called from within the constructor to initialize the form.
* WARNING: Do NOT modify this code. The content of this method is always
* regenerated by the Form Editor.
*/
@SuppressWarnings("unchecked")
// <editor-fold defaultstate="collapsed" desc="Generated Code">
private void initComponents() {
selectedGraph = new javax.swing.JTextField();
setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
selectedGraph.setEditable(false);
selectedGraph.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
selectedGraphActionPerformed(evt);
}
});
javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
getContentPane().setLayout(layout);
layout.setHorizontalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addGap(435, 435, 435)
.addComponent(selectedGraph, javax.swing.GroupLayout.PREFERRED_SIZE, 249, javax.swing.GroupLayout.PREFERRED_SIZE)
.addContainerGap(596, Short.MAX_VALUE))
);
layout.setVerticalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(layout.createSequentialGroup()
.addGap(126, 126, 126)
.addComponent(selectedGraph, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
.addContainerGap(646, Short.MAX_VALUE))
);
pack();
}// </editor-fold>
private void selectedGraphActionPerformed(java.awt.event.ActionEvent evt) {
}
public void addItem(String graphSelectedString1){
DefineEquation graphSelectedObj = new DefineEquation(graphSelected);
String graphSelectedStringMAIN = graphSelectedString1.toString();
selectedGraph.setText(graphSelectedStringMAIN);
}
/**
* @param args the command line arguments
*/
public static void main(String args[]) {
/* Set the Nimbus look and feel */
//<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
/* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel.
* For details see http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html
*/
try {
for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
if ("Nimbus".equals(info.getName())) {
javax.swing.UIManager.setLookAndFeel(info.getClassName());
break;
}
}
} catch (ClassNotFoundException ex) {
java.util.logging.Logger.getLogger(DefineEquation.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (InstantiationException ex) {
java.util.logging.Logger.getLogger(DefineEquation.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (IllegalAccessException ex) {
java.util.logging.Logger.getLogger(DefineEquation.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (javax.swing.UnsupportedLookAndFeelException ex) {
java.util.logging.Logger.getLogger(DefineEquation.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
}
//</editor-fold>
/* Create and display the form */
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
new DefineEquation().setVisible(true);
}
});
}
// Variables declaration - do not modify
private javax.swing.JTextField selectedGraph;
// End of variables declaration
}
您会注意到我尝试 "extend" 我的第一个 JFrame，但这导致第二个 JFrame "window" 以某种方式与第一个 JFrame "window."
结合概念图：
编辑 1：这是完成它的最佳方式吗？如果是这样，我将如何移动数据？对象目前让我感到困惑，还有一些非静态和静态问题，这些问题似乎无效，因为我没有任何静态问题。如果这不是最好的方法，我该怎么办？我要睡觉了，请大家多提建议和帮助，我不仅很绝望，而且很失落。
编辑 2：我正在尝试使用 m.cekiera 的答案，请在回答之前参考他的答案，因为它可能会有帮助。
编辑 3：仍然卡住了，需要详细帮助，很抱歉这么苛刻，但我无法解决这个问题。
编辑 4：我想我找到了重大突破。我已经想出如何解决这个问题，但我真的认为我需要理解这一点。不管怎样，我有一个新的 class 和一个不同的 class 的新文本字段。我仍然有问题，我无法显示文本字段的值，但由于某种原因我可以输出相同的值。我想它更容易显示
所以这是 class SelectSolutionsQuadratic:
public void displayText(String textToSet) {
displayQuadraticEquation.setText(textToSet);
System.out.println(textToSet);
}
这是 DefineEquationQuadratic:
private void nextActionPerformed(java.awt.event.ActionEvent evt) {
this.setVisible(false);
new SelectSolutionsQuadratic().setVisible(true);
SelectSolutionsQuadratic transferMe = new SelectSolutionsQuadratic();
transferData = aQuadraticSpinner.getValue().toString() + " " + addSubQuadraticComboBox.getSelectedItem();
transferMe.displayText(transferData);
}
所以基本上我只是很困惑为什么我可以将一个值从 DefineEquationQuadratic 发送到 SelectSolutionsQuadratic，然后用 System.out.println() 输出它；但是 NOT 将文本字段设置为该值
如果您只是不想将数据发送到 DefineEquation class，您应该在 nextActionPerformed:
String 参数的构造函数
new DefineEquation((String)graphSelection.getSelectedItem()).setVisible(true);
而不是：
new DefineEquation().setVisible(true);
您还需要将构造函数更改为：
public DefineEquation(String graphSelected) {
this.graphSelected = graphSelected;
initComponents();
}
因为现在没有 initComponents() 它将显示空框。
最后，你需要在DefineEquationclass中setText()到JTextField，例如：
selectedGraph = new javax.swing.JTextField(graphSelected);
不要使用 addItem() 方法或重写它，因为它会创建新的 DefineEquation 对象，这是不必要的，甚至是有害的。这样在新框架中它会显示 JTextField 和所选文本。它对我有用，至少如果我正确理解了你的问题。
但是，我宁愿使用 enums 而不是普通的 String，因为它们更可靠。您的函数集是不变的，因此您可以创建例如：
public enum Functions {NONE,LINEAR,BILINEAR,QUADRIATIC,CUBIC,EXPONENTIAL;}
这将需要更改构造函数和 JComboBox 内容，但您可以在整个应用程序中使用它。你可以在需要String显示的地方调用toString()或name()，但在事件处理等中使用枚举。
我认为您还应该按照评论中的建议重新考虑对多个 JFrames 的处理方法。我也不建议这样做，但这取决于您。
祝你好运！
编辑
如果你不想在DefineEquation中更改initComponents()，你仍然可以像这样修改addItem()：
public void addItem(){
selectedGraph.setText(graphSelected);
}
但随后您在构造函数中调用 addItem()，以用所选文本填充 JTextField。
或者您可以将 graphSelected 作为方法的参数传递，如果是这样，它不必是 class 字段。
我的建议是创建两个 JPanel classes，一个保存 JComboBox，另一个显示或需要结果。假设您已经这样做并调用了第一个 class、HoldsComboBoxPanel，并且您的第二个 class 被称为 ShowSelectionPanel，那么您将为 HoldsComboBoxPanel 提供两个方法，一个是获取当前选择，一个 "getter" 方法，另一个允许外部 classes 将 ActionListener 添加到组合框。例如，简而言之，像这样：
public class HoldsComboBoxPanel extends JPanel {
public static final String NAME = "holds combobox panel";
// sample data
private static final String[] DATA = { "Monday", "Tuesday", "Wednesday",
"Thursday", "Friday" };
private JComboBox<String> comboBox = new JComboBox<>(DATA);
public HoldsComboBoxPanel() {
// add the comboBox into our class here
}
// method to add a listener
public void addComboBoxListener(ActionListener listener) {
comboBox.addActionListener(listener);
}
// getter method
public String getComboSelection() {
return (String) comboBox.getSelectedItem();
}
}
你的第二个 class，需要数据的那个将有一个 setter 方法允许外部 classes 将组合选择推入其中的能力。假设它有一个名为 displayField 的 JTextField 来显示选择，它的代码可能如下所示：
public class ShowSelectionPanel extends JPanel {
public static final String NAME = "show selection panel";
private JTextField displayField = new JTextField(10);
public ShowSelectionPanel() {
// add the displayField to the JPanel here
}
// setter method
public void setDisplayText(String text) {
displayField.setText(text);
// or do whatever else you want to do with the selection
}
}
然后您将有另一个 class 使用 CardLayout 并允许在上面的视图 JPanel 之间交换，例如称为 MainPanel。它可以使用 CardLayout 来允许您交换 JPanel，有一个 public 方法允许外部 classes 交换 "card" JPanel，并且它会同时包含 HoldsComboBoxPanel 字段和 ShowSelectionPanel 字段，并且可以通过将 ActionListener 添加到组合框来 link 它们，如下所示：
public class MainPanel extends JPanel {
private CardLayout cardLayout = new CardLayout();
private MenuPanel menuPanel = new MenuPanel();
private HoldsComboBoxPanel holdsComboBoxPanel = new HoldsComboBoxPanel();
private ShowSelectionPanel showSelectionPanel = new ShowSelectionPanel();
public MainPanel() {
// add an ActionListener to the JComboBox
holdsComboBoxPanel.addComboBoxListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
// get the combo's selected String
String selection = holdsComboBoxPanel.getComboSelection();
if (selection != null) {
// push it into showSelection
showSelectionPanel.setDisplayText(selection);
}
}
});
setLayout(cardLayout);
add(menuPanel, MenuPanel.NAME);
add(holdsComboBoxPanel, HoldsComboBoxPanel.NAME);
add(showSelectionPanel, ShowSelectionPanel.NAME);
}
// method that allows outside classes to swap views
public void showCard(String key) {
cardLayout.show(this, key);
}
}
带有一些额外代码以允许在 "cards" 中移动的整个过程看起来像这样：
import java.awt.BorderLayout;
import java.awt.CardLayout;
import java.awt.Component;
import java.awt.Container;
import java.awt.Dimension;
import java.awt.GridBagLayout;
import java.awt.GridLayout;
import java.awt.Window;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import javax.swing.AbstractAction;
import javax.swing.AbstractButton;
import javax.swing.Action;
import javax.swing.BorderFactory;
import javax.swing.JButton;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JPopupMenu;
import javax.swing.JTextField;
import javax.swing.SwingUtilities;
public class SimpleMultPanels {
private static void createAndShowGui() {
// create JFrame
JFrame frame = new JFrame("SimpleMultPanels");
frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
// add our MainPanel to the JFrame
frame.getContentPane().add(new MainPanel());
frame.pack(); // pack it
frame.setLocationByPlatform(true);
frame.setVisible(true); // show it
}
public static void main(String[] args) {
// this is for starting our Swing app on the event thread
SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGui();
}
});
}
}
@SuppressWarnings("serial")
class MainPanel extends JPanel {
private CardLayout cardLayout = new CardLayout();
// the three "card" JPanels that this JPanel displays:
private MenuPanel menuPanel = new MenuPanel();
private HoldsComboBoxPanel holdsComboBoxPanel = new HoldsComboBoxPanel();
private ShowSelectionPanel showSelectionPanel = new ShowSelectionPanel();
// Actions for our JButtons
private ExitAction exitAction = new ExitAction();
private ShowAction backToMenuAction = new ShowAction(this, "Back to Menu",
MenuPanel.NAME, KeyEvent.VK_B);
private ShowAction toHoldsComboAction = new ShowAction(this, "Combo Panel",
HoldsComboBoxPanel.NAME, KeyEvent.VK_C);
private ShowAction toShowSelectionAction = new ShowAction(this,
"Show Selection", ShowSelectionPanel.NAME, KeyEvent.VK_S);
public MainPanel() {
// add an ActionListener to the JComboBox
holdsComboBoxPanel.addComboBoxListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
// get the combo's selected String
String selection = holdsComboBoxPanel.getComboSelection();
if (selection != null) {
// push it into showSelection
showSelectionPanel.setDisplayText(selection);
}
}
});
// add Actions to class to allow swapping of cards and
holdsComboBoxPanel.addButtonAction(backToMenuAction);
holdsComboBoxPanel.addButtonAction(toShowSelectionAction);
holdsComboBoxPanel.addButtonAction(exitAction); // and to exit gui
showSelectionPanel.addButtonAction(backToMenuAction);
showSelectionPanel.addButtonAction(toHoldsComboAction);
showSelectionPanel.addButtonAction(exitAction);
menuPanel.addButtonAction(toHoldsComboAction);
menuPanel.addButtonAction(toShowSelectionAction);
menuPanel.addButtonAction(exitAction);
setBorder(BorderFactory.createEmptyBorder(5, 5, 5, 5));
// set our layout
setLayout(cardLayout);
// and add our "card" JPanels
add(menuPanel, MenuPanel.NAME);
add(holdsComboBoxPanel, HoldsComboBoxPanel.NAME);
add(showSelectionPanel, ShowSelectionPanel.NAME);
}
// method that allows outside classes to swap views
public void showCard(String key) {
cardLayout.show(this, key);
}
}
@SuppressWarnings("serial")
class HoldsComboBoxPanel extends JPanel {
// constant String that will be used by the CardLayout
public static final String NAME = "holds combobox panel";
// sample data
private static final String[] DATA = { "Monday", "Tuesday", "Wednesday",
"Thursday", "Friday" };
private JComboBox<String> comboBox = new JComboBox<>(DATA);
// JPanel to hold buttons to allow moving between cards
private JPanel buttonPanel = new JPanel(new GridLayout(1, 0, 5, 0));
public HoldsComboBoxPanel() {
comboBox.setSelectedIndex(-1);
JPanel centerPanel = new JPanel();
centerPanel.add(comboBox);
setLayout(new BorderLayout());
add(centerPanel, BorderLayout.CENTER);
add(buttonPanel, BorderLayout.SOUTH);
}
// method to add a listener
public void addComboBoxListener(ActionListener listener) {
comboBox.addActionListener(listener);
}
// getter method
public String getComboSelection() {
return (String) comboBox.getSelectedItem();
}
// create a new JButton with an Action and add to buttonPanel
public void addButtonAction(Action action) {
buttonPanel.add(new JButton(action));
}
}
@SuppressWarnings("serial")
class ShowSelectionPanel extends JPanel {
public static final String NAME = "show selection panel";
private static final int PREF_W = 300;
private static final int PREF_H = PREF_W;
private JTextField displayField = new JTextField(10);
private JPanel buttonPanel = new JPanel(new GridLayout(1, 0, 5, 0));
public ShowSelectionPanel() {
displayField.setFocusable(false);
JPanel centerPanel = new JPanel();
centerPanel.add(displayField);
setLayout(new BorderLayout());
add(centerPanel, BorderLayout.CENTER);
add(buttonPanel, BorderLayout.SOUTH);
}
// code to make our GUI a little larger
@Override
public Dimension getPreferredSize() {
Dimension superSz = super.getPreferredSize();
if (isPreferredSizeSet()) {
return superSz;
}
int prefW = Math.max(superSz.width, PREF_W);
int prefH = Math.max(superSz.height, PREF_H);
return new Dimension(prefW, prefH);
}
// setter method
public void setDisplayText(String text) {
displayField.setText(text);
// or do whatever else you want to do with the selection
}
public void addButtonAction(Action action) {
buttonPanel.add(new JButton(action));
}
}
@SuppressWarnings("serial")
class MenuPanel extends JPanel {
public static final String NAME = "menu panel";
private JPanel buttonPanel = new JPanel(new GridLayout(0, 1, 0, 5));
public MenuPanel() {
setLayout(new GridBagLayout());
add(buttonPanel);
}
public void addButtonAction(Action action) {
buttonPanel.add(new JButton(action));
}
}
@SuppressWarnings("serial")
class ShowAction extends AbstractAction {
private MainPanel mainPanel;
private String key;
/**
* Abstract Action used by JButtons
* @param mainPanel: the JPanel that uses the CardLayout
* @param name: The name displayed by the button
* @param key: The key used in the CardLayout#show(String key) mehtod
* @param mnemonic: the JButton's mnemonic char
*/
public ShowAction(MainPanel mainPanel, String name, String key, int mnemonic) {
super(name);
putValue(MNEMONIC_KEY, mnemonic);
this.mainPanel = mainPanel;
this.key = key;
}
@Override
public void actionPerformed(ActionEvent e) {
// tell the mainPanel to show the card associated with the key
mainPanel.showCard(key);
}
}
// class of mine to allow disposing of a window
// It's a little complex to allow it to work with either a JButton
// or a JMenuItem
@SuppressWarnings("serial")
class ExitAction extends AbstractAction {
public ExitAction() {
super("Exit");
putValue(MNEMONIC_KEY, KeyEvent.VK_X);
}
@Override
public void actionPerformed(ActionEvent e) {
// get the button that caused this action
Object source = e.getSource();
if (source instanceof AbstractButton) {
AbstractButton exitButton = (AbstractButton) source;
// get the parent top level window
Window topWindow = SwingUtilities.getWindowAncestor(exitButton);
if (topWindow == null) { // if null, then likely in a JMenuItem
// so we have to get its jpopupmenu parent
Container parent = exitButton.getParent();
if (parent instanceof JPopupMenu) {
JPopupMenu popupMenu = (JPopupMenu) parent;
// get the invoker for the pop up menu
Component invoker = popupMenu.getInvoker();
if (invoker != null) {
// and get *its* top level window
topWindow = SwingUtilities.getWindowAncestor(invoker);
}
}
}
if (topWindow != null) {
// dispose of the top-level window
topWindow.dispose();
}
}
}
}
所以我真的很笨，创建了两个实例，其中一个我没有查看，另一个我查看但没有更改。基本上我所做的是在 graphSelectionActionPerformed 我做了：
this.graphSelectionGUI = (String)graphSelection.getSelectedItem();
然后在 nextActionPerformed 中我做了：
new DefineEquation_1(graphSelectionGUI).setVisible(true);
在此之后，在另一个 class (DefineEquation) 中，我使用我的构造函数并执行了以下操作：
public DefineEquation(String graphSelected) {
this.graphSelected = graphSelected;
initComponents();
selectedGraph.setText(graphSelected);
}
最后我泪流满面，才知道自己给你们带来了多大的麻烦，自己是多么的愚蠢，赞美主！
不好意思给大家添麻烦了，不好意思