java - 更新框架或重新验证/重绘面板

Question

如何用更改的内容更新 Java 框架？

我想用更新的内容更新框架或面板。我用这个做什么

这是我想重新验证框架或重新绘制主面板或任何可以工作的地方我尝试了很多方法，但都没有用。

public void actionPerformed(ActionEvent e) {
        //System.out.println(e.getActionCommand());
        if (e.getActionCommand().equals("advance")) {
            multi--;
                    // Revalidate update repaint here <<<<<<<<<<<<<<<<<<<
        }
        else if (e.getActionCommand().equals("reverse")) {
            multi++;
                    // Revalidate update repaint here <<<<<<<<<<<<<<<<<<<       
        }
        else {
            openURL(e.getActionCommand());
        }

        }

这是整个java文件

/*
 *
 *
 */ 

package build;

import java.lang.reflect.Method;
import javax.swing.JOptionPane;
import java.util.Arrays;
import java.util.*;
import java.util.ArrayList;

import javax.swing.*;
import javax.swing.AbstractButton;
import javax.swing.JScrollPane;
import javax.swing.JButton;
import javax.swing.JPanel;
import javax.swing.JFrame;
import javax.swing.ImageIcon;

import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;

/* 
 * ButtonDemo.java requires the following files:
 *   images/right.gif
 *   images/middle.gif
 *   images/left.gif
 */
public class StockTable extends JPanel
                        implements ActionListener {
    static int multi = 1;
    int roll = 0;
    static TextVars textvars = new TextVars();
    static final String[] browsers = { "firefox", "opera", "konqueror", "epiphany",
            "seamonkey", "galeon", "kazehakase", "mozilla", "netscape" };
    JFrame frame;
    JPanel mainpanel, panel1, panel2, panel3, panel4, panel2left, panel2center, panel2right;
        JButton stknames_btn[] = new JButton[textvars.getNumberOfStocks()];
    JLabel label[] = new JLabel[textvars.getNumberOfStocks()];
    JLabel headlabel, dayspan, namelabel;
    JRadioButton radioButton;
    JButton button;
    JScrollPane scrollpane;
    int wid = 825;
    public JPanel createContentPane() {

        mainpanel = new JPanel();
        mainpanel.setPreferredSize(new Dimension(wid, 800));
        mainpanel.setLayout(new GridBagLayout());
        GridBagConstraints c = new GridBagConstraints();
        panel1 = new JPanel();
        panel1.setPreferredSize(new Dimension(wid, 25));
        c.gridx = 0;
        c.gridy = 0;
        c.insets = new Insets(0,0,0,0);
        mainpanel.add(panel1, c);

        // Panel 2------------
        panel2 = new JPanel();
        panel2.setPreferredSize(new Dimension(wid, 51));
        c.gridx = 0;
        c.gridy = 1;
        c.insets = new Insets(0,0,0,0);
        mainpanel.add(panel2, c);
        panel2left = new JPanel();
        panel2left.setPreferredSize(new Dimension(270, 51));
        c.gridx = 0;
        c.gridy = 1;
        c.insets = new Insets(0,0,0,0);
        panel2.add(panel2left, c);
        panel2center = new JPanel();
        panel2center.setPreferredSize(new Dimension(258, 51));
        c.gridx = 1;
        c.gridy = 1;
        c.insets = new Insets(0,0,0,0);
        panel2.add(panel2center, c);
        panel2right = new JPanel();
        panel2right.setPreferredSize(new Dimension(270, 51));
        c.gridx = 2;
        c.gridy = 1;
        c.insets = new Insets(0,0,0,0);
        panel2.add(panel2right, c);
        // ------------------

        panel3 = new JPanel();
        panel3.setLayout(new GridBagLayout());
        scrollpane = new JScrollPane(panel3);
        scrollpane.setPreferredSize(new Dimension(wid, 675));
        c.gridx = 0;
        c.gridy = 2;
        c.insets = new Insets(0,0,0,0);
        mainpanel.add(scrollpane, c);


            ImageIcon leftButtonIcon = createImageIcon("images/right.gif");

            //b1 = new JButton("Disable middle button", leftButtonIcon);
            //b1.setVerticalTextPosition(AbstractButton.CENTER);
            //b1.setHorizontalTextPosition(AbstractButton.LEADING); //aka LEFT, for left-to-right locales
            //b1.setMnemonic(KeyEvent.VK_D);
            //b1.setActionCommand("disable");


            //Listen for actions on buttons 1
            //b1.addActionListener(this);

            //b1.setToolTipText("Click this button to disable the middle button.");

            //Add Components to this container, using the default FlowLayout.
            //add(b1);


        headlabel = new JLabel("hellorow1");
            c.gridx = 0;       
            c.gridy = 0;       
        c.insets = new Insets(0, 0, 0, 0);
        panel1.add(headlabel, c);

        radioButton = new JRadioButton("Percentage");
            c.gridx = 2;       
            c.gridy = 0;       
        c.insets = new Insets(0, 0, 0, 0);
        panel1.add(radioButton, c);

        radioButton = new JRadioButton("Days Range");
            c.gridx = 3;      
            c.gridy = 0;      
        c.insets = new Insets(0, 0, 0, 0);
        panel1.add(radioButton, c);

        radioButton = new JRadioButton("Open / Close");
            c.gridx = 4;       
            c.gridy = 0;       
        c.insets = new Insets(0, 0, 0,0 );
        panel1.add(radioButton, c);


        button = new JButton("<<");
        button.setPreferredSize(new Dimension(50, 50));
        button.setActionCommand("reverse");
        button.addActionListener(this);
            c.gridx = 0;       
            c.gridy = 1;       
        c.insets = new Insets(0, 0, 0, 0);
            panel2left.add(button, c);

        dayspan = new JLabel("hellorow2"); 
        dayspan.setHorizontalAlignment(JLabel.CENTER); 
        dayspan.setVerticalAlignment(JLabel.CENTER);
        dayspan.setPreferredSize(new Dimension(270, 50)); 
            c.gridx = 1;       
            c.gridy = 1;
        c.insets = new Insets(0, 0, 0, 0);       
            panel2center.add(dayspan, c);

        button = new JButton(">>");
        button.setPreferredSize(new Dimension(50, 50));
        button.setActionCommand("advance");
        button.addActionListener(this);
        if (multi == 0) {
            button.setEnabled(false);
        }
        else {
            button.setEnabled(true);
        }
            c.gridx = 2;       
            c.gridy = 1;       
        c.insets = new Insets(0, 0, 0, 0);
            panel2right.add(button, c);

        int availSpace_int = textvars.getStocks().size()-textvars.getNumberOfStocks()*7;

        ArrayList<String[]> stocknames = textvars.getStockNames();
        ArrayList<String[]> stocks = textvars.getStocks();
        for (int column = 0; column < 8; column++) {
            for (int row = 0; row < textvars.getNumberOfStocks(); row++) { 

                if (column==0) {
                    if (row==0) {
                        namelabel = new JLabel(stocknames.get(0)[0]); 
                        namelabel.setVerticalAlignment(JLabel.CENTER);
                        namelabel.setHorizontalAlignment(JLabel.CENTER);
                        namelabel.setPreferredSize(new Dimension(100, 25));
                        c.gridx = column;
                        c.gridy = row;
                        c.insets = new Insets(0, 0, 0, 0);
                        panel3.add(namelabel, c);
                    }
                    else {
                        stknames_btn[row] = new JButton(stocknames.get(row)[0], leftButtonIcon); 
                        stknames_btn[row].setVerticalTextPosition(AbstractButton.CENTER);
                        stknames_btn[row].setActionCommand(stocknames.get(row)[1]); 
                        stknames_btn[row].addActionListener(this);
                        stknames_btn[row].setToolTipText("go to Google Finance "+stocknames.get(row)[0]); 
                        stknames_btn[row].setPreferredSize(new Dimension(100, 25));
                        c.gridx = column;
                        c.gridy = row;
                        c.insets = new Insets(0, 0, 0, 0);
                        //scrollpane.add(stknames[row], c);
                        panel3.add(stknames_btn[row], c);
                    }
                }
                else {
                        label[row]= new JLabel(textvars.getStocks().get(columnMulti(multi))[1]);
                        label[row].setBorder(BorderFactory.createLineBorder(Color.black));
                        label[row].setVerticalAlignment(JLabel.CENTER);
                        label[row].setHorizontalAlignment(JLabel.CENTER);
                        label[row].setPreferredSize(new Dimension(100, 25));    
                        c.gridx = column;
                        c.gridy = row;
                        c.insets = new Insets(0,0,0,0);
                        panel3.add(label[row], c);
                }

            }
        }

        return mainpanel;
        }

        public void actionPerformed(ActionEvent e) {
        //System.out.println(e.getActionCommand());
        if (e.getActionCommand().equals("advance")) {
            multi--;
        }
        else if (e.getActionCommand().equals("reverse")) {
            multi++;        
        }
        else {
            openURL(e.getActionCommand());
        }

        }

        /** Returns an ImageIcon, or null if the path was invalid. */
        protected static ImageIcon createImageIcon(String path) {
            java.net.URL imgURL = StockTable.class.getResource(path);
            if (imgURL != null) {
                    return new ImageIcon(imgURL);
            } else {
                    System.err.println("Couldn't find file: " + path);
                    return null;
            }
        }

    public static void openURL(String url) {
        String osName = System.getProperty("os.name");
        try {
            if (osName.startsWith("Mac OS")) {
                Class<?> fileMgr = Class.forName("com.apple.eio.FileManager");
                Method openURL = fileMgr.getDeclaredMethod("openURL",
                    new Class[] {String.class});
                openURL.invoke(null, new Object[] {url});
                        }
            else if (osName.startsWith("Windows")) {    
                Runtime.getRuntime().exec("rundll32 url.dll,FileProtocolHandler " + url);
            }
            else { //assume Unix or Linux
                boolean found = false;
                for (String browser : browsers)
                    if (!found) {
                        found = Runtime.getRuntime().exec(
                        new String[] {"which", browser}).waitFor() == 0;
                        if (found) 
                            Runtime.getRuntime().exec(new String[] {browser, url}); 
                    }   
                    if (!found)
                        throw new Exception(Arrays.toString(browsers));
                    }
                }   
        catch (Exception e) {   
            JOptionPane.showMessageDialog(null,
                "Error attempting to launch web browser\n" + e.toString());
        }
    }
    int reit = 0;
    int start = textvars.getStocks().size()-((textvars.getNumberOfStocks()*5)*7)-1;
    public int columnMulti(int multi) {
        reit++;
        start++;
        if (reit == textvars.getNumberOfStocks()) {
            reit = 0;
            start=start+64;
        }
        //start = start - (multi*(textvars.getNumberOfStocks()));
        return start;
    }

        /**
        * Create the GUI and show it.  For thread safety, 
        * this method should be invoked from the 
        * event-dispatching thread.
        */
        private static void createAndShowGUI() {

        //Create and set up the window.
            JFrame frame = new JFrame("Stock Table");
            frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

            //Create and set up the content pane.
            StockTable newContentPane = new StockTable();
            //newContentPane.setOpaque(true); //content panes must be opaque
            //frame.setContentPane(newContentPane);
        frame.setContentPane(newContentPane.createContentPane());
        frame.setSize(800, 800);


            //Display the window.
            frame.pack();
            frame.setVisible(true);


        }

    public static void main(String[] args) {
            //Schedule a job for the event-dispatching thread:
            //creating and showing this application's GUI.
            javax.swing.SwingUtilities.invokeLater(new Runnable() {
                    public void run() {
                        createAndShowGUI(); 
                    }
            });
        }
}

Answer 1

当您发现自己想要基于一个小改动“重新创建”一个 UI 时，应该敲响警钟了。在某些情况下，这会是个好主意，但在大多数情况下，这是糟糕设计的标志。

让我们从...开始

frame.setContentPane(newContentPane.createContentPane());

这是个坏主意。您创建一个 JPanel 只是为了创建另一个 JPanel。突然之间，您并没有失去 UI 的上下文。

而不是 createContentPane，从 StockTable Pane 的构造函数中简单地构造您的 UI，并将其添加到框架中......更像......

frame.setContentPane(newContentPane);

摆脱 mainPanel 并直接使用 StockTable 面板。

我无法运行您的代码，但它看起来很像是您在尝试“模拟”表格布局。相反，简化你的生活并学会使用 JTable .如果你这样做，更新表格会更容易得多(更不用说看起来更好了)......