我正在制作家谱，这是我的问题。我有屏幕NewFamilyTree.java和NewPerson.java。
NewFamilyTree.java：
public class NewFamilyTree {
...
private void initialize() {
frame = new JFrame();
frame.setTitle("New family tree");
frame.setBounds(100, 100, 906, 569);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
...
JTabbedPane tabbedPane = new JTabbedPane(JTabbedPane.TOP);
frame.getContentPane().add(tabbedPane, BorderLayout.CENTER);
JScrollPane scrollPane = new JScrollPane();
tabbedPane.addTab("Tree", null, scrollPane, null);
panel_1 = new JPanel();
scrollPane.setViewportView(panel_1);
panel_1.setLayout(new MigLayout("", "[][][][][][][][]", "[][][][][][]"));
NewPerson.java：
public class NewPerson{
...
buttonAdd = new JButton("Add");
buttonAdd.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent arg0) {
String names = textFieldNames.getText();
String dateBirth = textFieldDateOfBirth.getText();
String bio = textAreaBio.getText();
Data newData = new Data(names, dateBirth, bio, fileID);
//code that puts new label on scrollpane from NewFamilyTree.java
}
});
buttonAdd.setBackground(new Color(30, 144, 255));
frame.getContentPane().add(buttonAdd, "cell 2 6,grow");
}
我需要在new JLabel的{{1}}上按下按钮添加，从而class NewPerson添加JScrollPane。希望有人可以提供帮助，我搜索了很多，无法帮助自己。
编辑：在@mjr的答案之后。
我在NewFamilytree.java中添加了public JPanel panel_1;。在NewFamilyTree执行的操作中，我添加了：
Add没有错误，但是 - 按 add 按钮后没有任何反应。我还添加了JLabel lblHomer = new JLabel("Homer");
lblHomer.setIcon(new ImageIcon("C:\\Users\\Tinmar\\Desktop\\HomerSimpson3.gif"));
panel_1.add(lblHomer, "cell 7 5");
，NewPerson EXTENDS NewFamilyTree。
答案 0 :(得分：3)
NewPerson不需要从NewFamilyTree扩展，它不会向该类添加任何功能JFrame中使用NewPerson，而应考虑使用模式JDialog。有关详细信息，请参阅How to Make Dialogs NewFamilyTree没有理由能够访问NewPerson使用的“窗口”。 NewPerson没有理由为NewFamilyTree java.awt.Button）与轻质组件混合使用，这可能导致问题无法解决...... 你需要改变你对事物的看法。不要试图NewPerson更新NewFamilyTree的用户界面，而是NewPerson从用户收集详细信息并将此信息传回NewFamilyTree，以便它可以使用它...
例如......
JButton newPersonButton = new JButton("New Person");
newPersonButton.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent arg0) {
Data data = NewPerson.createPerson(frame);
if (data != null) {
JLabel lblHomer = new JLabel(data.names);
panel_1.add(lblHomer, "cell 7 5");
panel_1.revalidate();
}
}
});
这基本上使用了static方法createPerson，该方法会传回Data的实例（如果用户取消了操作，则返回null）NewFamilyTree然后可以使用。它将代码分离，因为NewPerson并不依赖NewFamilyTree和NewFamilyTree维持控制的任何内容。这清楚地定义了两个类之间的责任区域，这也意味着可以从任何地方调用NewPerson ......
createPerson方法看起来像是......
public static Data createPerson(Component comp) {
NewPerson newPerson = new NewPerson();
Window win = SwingUtilities.getWindowAncestor(comp);
JDialog dialog = null;
if (win instanceof Frame) {
dialog = new JDialog((Frame) win, "New person", true);
} else if (win instanceof Dialog) {
dialog = new JDialog((Dialog) win, "New person", true);
} else {
dialog = new JDialog((Frame) null, "New person", true);
}
newPerson.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
Object source = e.getSource();
if (source instanceof Component) {
Window win = SwingUtilities.getWindowAncestor((Component) source);
win.dispose();
}
}
});
dialog.add(newPerson);
dialog.setVisible(true);
return newPerson.getData();
}
它基本上创建JDialog的实例，向用户显示它并等待NewPerson类触发ActionEvent，它用于处理对话框。然后它会询问NewPerson的实例数据......
因为有一大堆我没有谈过的功能，这里有一个完全可运行的例子......
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Component;
import java.awt.Dialog;
import java.awt.EventQueue;
import java.awt.Frame;
import java.awt.Window;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.File;
import javax.swing.JButton;
import javax.swing.JDialog;
import javax.swing.JFileChooser;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTabbedPane;
import javax.swing.JTextArea;
import javax.swing.JTextField;
import javax.swing.SwingUtilities;
import net.miginfocom.swing.MigLayout;
public class NewFamilyTree {
private JFrame frame;
private JPanel panel_1;
private JScrollPane scrollPane;
private JTabbedPane tabbedPane;
/**
* Launch the application.
*/
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
public void run() {
try {
NewFamilyTree window = new NewFamilyTree();
window.frame.setVisible(true);
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
/**
* Create the application.
*/
public NewFamilyTree() {
initialize();
}
/**
* Initialize the contents of the frame.
*/
private void initialize() {
frame = new JFrame();
frame.setTitle("New family tree");
frame.getContentPane().setBackground(new Color(135, 206, 250));
frame.setBounds(100, 100, 906, 569);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JPanel panel = new JPanel();
panel.setBackground(new Color(30, 144, 255));
frame.getContentPane().add(panel, BorderLayout.EAST);
panel.setLayout(new MigLayout("", "[]", "[][][][][][][][]"));
JButton newPersonButton = new JButton("New Person");
newPersonButton.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent arg0) {
Data data = NewPerson.createPerson(frame);
if (data != null) {
JLabel lblHomer = new JLabel(data.names);
// lblHomer.setIcon(new ImageIcon("C:\\Users\\Tinmar\\Desktop\\HomerSimpson3.gif"));
panel_1.add(lblHomer, "cell 7 5");
panel_1.revalidate();
}
}
});
panel.add(newPersonButton, "cell 0 5");
JButton btnNewButton_1 = new JButton("New button");
panel.add(btnNewButton_1, "cell 0 6");
tabbedPane = new JTabbedPane(JTabbedPane.TOP);
frame.getContentPane().add(tabbedPane, BorderLayout.CENTER);
scrollPane = new JScrollPane();
tabbedPane.addTab("Tree", null, scrollPane, null);
panel_1 = new JPanel();
scrollPane.setViewportView(panel_1);
panel_1.setLayout(new MigLayout("", "[][][][][][][][]", "[][][][][][]"));
// JLabel lblHomer = new JLabel("Homer");
// lblHomer.setIcon(new ImageIcon("C:\\Users\\Tinmar\\Desktop\\HomerSimpson3.gif"));
// panel_1.add(lblHomer, "cell 7 5");
JScrollPane scrollPane_1 = new JScrollPane();
tabbedPane.addTab("Info", null, scrollPane_1, null);
frame.repaint();
}
//
// /**
// * Launch the application.
// */
// public static void main(String[] args) {
// EventQueue.invokeLater(new Runnable() {
// public void run() {
// try {
// NewPerson window = new NewPerson();
// window.frame.setVisible(true);
// } catch (Exception e) {
// e.printStackTrace();
// }
// }
// });
// }
public static class NewPerson extends JPanel {
private JTextField textFieldNames;
private JButton selectPictureButton;
private JLabel labelDateOfBirth;
private JTextField textFieldDateOfBirth;
private JLabel labelShortBio;
private JTextArea textAreaBio;
private JLabel labelSelectPicture;
private JButton buttonAdd;
private String fileID;
private Data data;
/**
* Create the application.
*/
private NewPerson() {
initialize();
}
public static Data createPerson(Component comp) {
NewPerson newPerson = new NewPerson();
Window win = SwingUtilities.getWindowAncestor(comp);
JDialog dialog = null;
if (win instanceof Frame) {
dialog = new JDialog((Frame) win, "New person", true);
} else if (win instanceof Dialog) {
dialog = new JDialog((Dialog) win, "New person", true);
} else {
dialog = new JDialog((Frame) null, "New person", true);
}
newPerson.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
Object source = e.getSource();
if (source instanceof Component) {
Window win = SwingUtilities.getWindowAncestor((Component) source);
win.dispose();
}
}
});
dialog.add(newPerson);
dialog.pack();
dialog.setLocationRelativeTo(comp);
dialog.setVisible(true);
return newPerson.getData();
}
public void addActionListener(ActionListener listener) {
listenerList.add(ActionListener.class, listener);
}
protected void fireActionPerformed() {
ActionListener[] listeners = listenerList.getListeners(ActionListener.class);
if (listeners != null && listeners.length > 0) {
ActionEvent evt = new ActionEvent(this, ActionEvent.ACTION_PERFORMED, "created");
for (ActionListener listener : listeners) {
listener.actionPerformed(evt);
}
}
}
public Data getData() {
return data;
}
/**
* Initialize the contents of the frame.
*/
private void initialize() {
setBackground(new Color(135, 206, 250));
setLayout(new MigLayout("", "[][][grow]", "[][][][grow][][][]"));
JLabel labelNames = new JLabel("Name and Surname:");
add(labelNames, "cell 1 1,alignx trailing");
textFieldNames = new JTextField();
add(textFieldNames, "cell 2 1,growx");
textFieldNames.setColumns(10);
labelDateOfBirth = new JLabel("Date of birth:");
add(labelDateOfBirth, "cell 1 2,alignx center,aligny center");
textFieldDateOfBirth = new JTextField();
add(textFieldDateOfBirth, "cell 2 2,growx");
textFieldDateOfBirth.setColumns(10);
labelShortBio = new JLabel("Bio:");
add(labelShortBio, "cell 1 3,alignx center,aligny center");
textAreaBio = new JTextArea();
add(textAreaBio, "cell 2 3,grow");
labelSelectPicture = new JLabel("Select picture:");
add(labelSelectPicture, "cell 1 4,alignx center,aligny center");
selectPictureButton = new JButton("...");
selectPictureButton.setBackground(new Color(30, 144, 255));
selectPictureButton.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent arg0) {
JFileChooser chooser = new JFileChooser(new File(System.getProperty("user.home") + "\\Desktop"));
chooser.setDialogTitle("Select Location");
chooser.setFileSelectionMode(JFileChooser.APPROVE_OPTION);
chooser.setAcceptAllFileFilterUsed(false);
if (chooser.showSaveDialog(null) == JFileChooser.APPROVE_OPTION) {
fileID = chooser.getSelectedFile().getPath();
// txtField.setText(fileID);
}
}
});
add(selectPictureButton, "cell 2 4");
buttonAdd = new JButton("Add");
buttonAdd.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent arg0) {
String names = textFieldNames.getText();
String dateBirth = textFieldDateOfBirth.getText();
String bio = textAreaBio.getText();
data = new Data(names, dateBirth, bio, fileID);
fireActionPerformed();
}
});
buttonAdd.setBackground(new Color(30, 144, 255));
add(buttonAdd, "cell 2 6,grow");
}
}
public static class Data {
private final String names;
private final String dateBirth;
private final String bio;
private final String fileID;
private Data(String names, String dateBirth, String bio, String fileID) {
this.names = names;
this.dateBirth = dateBirth;
this.bio = bio;
this.fileID = fileID;
}
}
}
static来跨类提供功能。如果您必须从其他类中获取某些内容，请将其作为参考传递。 static不是你的朋友，你应该小心并警惕它的使用interface s来允许课程提供或获取信息。这限制了其他类可以做的事情。答案 1 :(得分：1)
当您向NewPerson添加按钮时，可以在NewPerson中访问NewFamilyTree的frame，如果您要添加标签，则必须在NewPerson中访问scrollPane那个班。因此，使用scrollPane执行相同的操作就像使用frame一样，以便能够在NewPerson中使用它。
答案 2 :(得分：0)
我假设JScrollPane和addButton在不同的框架中......虽然它们确实可以在相同的框架中工作。 基本上，您需要为JScrollPane和JPanel提供getter，以便可以从NewPerson类访问它们。 在buttonAdd的动作侦听器中，如果标签不在面板当前大小的脚上，则需要增加面板的首选大小。当面板的首选大小大于JScrollPane的视图大小时，滚动条将自动出现。
请参阅以下代码： NewFamilyTree.jva：
package dva.test001;
import java.awt.BorderLayout;
import java.awt.Dimension;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTabbedPane;
public class NewFamilyTree {
private JFrame frame;
private JScrollPane scrollPane;
private JPanel panel;
public NewFamilyTree() {
initialize();
}
private void initialize() {
frame = new JFrame();
frame.setTitle("New family tree");
frame.setBounds(100, 100, 906, 569);
frame.setLayout(new BorderLayout());
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JTabbedPane tabbedPane = new JTabbedPane(JTabbedPane.TOP);
frame.getContentPane().add(tabbedPane, BorderLayout.CENTER);
panel = new JPanel();
panel.setPreferredSize(new Dimension(700, 300));
panel.setLayout(null);
scrollPane = new JScrollPane(panel);
tabbedPane.addTab("Tree", null, scrollPane, null);
frame.setVisible(true);
}
public static void main(String[] args) {
NewFamilyTree ft = new NewFamilyTree();
NewPerson np = new NewPerson(ft);
}
public JFrame getFrame() {
return frame;
}
public JScrollPane getScrollPane() {
return scrollPane;
}
public JPanel getPanel() {
return panel;
}
}
NewPerson.java：
package dva.test001;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
public class NewPerson {
private NewFamilyTree familyTree;
private static final int labelHeight = 30;
public NewPerson(NewFamilyTree familyTree) {
this.familyTree = familyTree;
init();
}
public void init() {
JFrame frame = new JFrame();
frame.setTitle("New Person");
frame.setBounds(100, 500, 906, 100);
JButton buttonAdd = new JButton("Add");
buttonAdd.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent arg0) {
String names = "names"; //textFieldNames.getText();
String dateBirth = "date"; //textFieldDateOfBirth.getText();
String bio = "bio"; //textAreaBio.getText();
//Data newData = new Data(names, dateBirth, bio, fileID);
//code that puts new label on scrollpane from NewFamilyTree.java
JLabel lbl = new JLabel(names);
int top = familyTree.getPanel().getComponentCount() * labelHeight;
if(top + labelHeight > familyTree.getPanel().getHeight()) {
familyTree.getPanel().setPreferredSize(new Dimension(familyTree.getPanel().getWidth(), top + labelHeight));
familyTree.getScrollPane().revalidate();
}
familyTree.getPanel().add(lbl);
lbl.setBounds(10, top, 100, labelHeight);
}
});
buttonAdd.setBackground(new Color(30, 144, 255));
frame.getContentPane().add(buttonAdd);
frame.setVisible(true);
}
}