Question

我尝试在框架中运行进度条，但它无法正常工作。我试图在我的第二个java类中显示可见，但设置visible（true）将其显示为错误。希望你们能帮助我解决我的问题/错误

在我的第二个java类中显示错误： “线程中的异常”主“ java.lang.Error：未解决的编译问题：方法对于类型mgfinancewindow“

，setvisible（boolean）未定义

First java class: mgfinancewindow.java
package mgfinance;

import java.awt.EventQueue;
import java.awt.Font;

import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JProgressBar;
import java.awt.Color;
import javax.swing.JLabel;
import javax.swing.SwingConstants;

public class mgfinancewindow {
private JFrame frame;
public JProgressBar progressBar;
public JLabel lblNewLabel;

/**
 * Launch the application.
 */
public static void main(String[] args) {
    EventQueue.invokeLater(new Runnable() {
        public void run() {
            try {
                mgfinancewindow window = new mgfinancewindow();
                window.frame.setVisible(true);
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    });
}

/**
 * Create the application.
 */
public mgfinancewindow() {
    initialize();
}

/**
 * Initialize the contents of the frame.
 */
private void initialize() {
    frame = new JFrame("MG Finances");
    frame.setBounds(100, 100, 450, 300);
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    frame.setExtendedState(JFrame.MAXIMIZED_BOTH);
    frame.getContentPane().setLayout(null);

    JPanel panel = new JPanel();
    panel.setBounds(0, 0, 1362, 705);
    frame.getContentPane().add(panel);
    panel.setLayout(null);

    JPanel panel_1 = new JPanel();
    panel_1.setBackground(Color.DARK_GRAY);
    panel_1.setBounds(0, 646, 1362, 59);
    panel.add(panel_1);
    panel_1.setLayout(null);

    lblNewLabel = new JLabel("Loading...");
    lblNewLabel.setFont(new Font("Tahoma", Font.BOLD | Font.ITALIC, 16));
    lblNewLabel.setHorizontalAlignment(SwingConstants.CENTER);
    lblNewLabel.setForeground(Color.WHITE);
    lblNewLabel.setBounds(1139, 0, 114, 34);
    panel_1.add(lblNewLabel);

    progressBar = new JProgressBar();
    progressBar.setBackground(new Color(0, 51, 51));
    progressBar.setBounds(0, 34, 1362, 14);
    panel_1.add(progressBar);

    JLabel lblMgFinance = new JLabel("MG Finance");
    lblMgFinance.setHorizontalAlignment(SwingConstants.CENTER);
    lblMgFinance.setFont(new Font("Tahoma", Font.BOLD | Font.ITALIC, 16));
    lblMgFinance.setForeground(Color.BLUE);
    lblMgFinance.setBounds(0, 11, 1362, 635);
    panel.add(lblMgFinance);


}

}

第二个java类：progressbar.java

package mgfinance;


public class progress {
public static void main(String[] args) throws InterruptedException{
    mgfinancewindow load = new mgfinancewindow();
    for(int i=0; i<=100; i++){
        Thread.sleep(150);
        load.setvisible(true);
        load.lblNewLabel.setText("Loading..."+ i);
        load.progressBar.setValue(i);
    }
}

}

Answer 1

您的mgfinancewindow课程不是JComponent来支持setVisible()方法本身。其中的JFrame具有setVisible方法。

在您编写代码的方式中，为了快速解决您的问题，您必须在frame.setVisible(true);类的initialize()方法的末尾（最后一条语句）写下mgfinancewindow并删除{{ 1}}来自load.setvisible(true);类的main方法：

progress

和

public class progress {
    public static void main(String[] args) throws InterruptedException {
        mgfinancewindow load = new mgfinancewindow();
        for (int i = 0; i <= 100; i++) {
            Thread.sleep(150);
            //load.setvisible(true);
            load.lblNewLabel.setText("Loading..." + i);
            load.progressBar.setValue(i);
        }
    }
}

<强>但是：

当您创建像import java.awt.Color; import java.awt.EventQueue; import java.awt.Font; import javax.swing.JFrame; import javax.swing.JLabel; import javax.swing.JPanel; import javax.swing.JProgressBar; import javax.swing.SwingConstants; public class mgfinancewindow { private JFrame frame; public JProgressBar progressBar; public JLabel lblNewLabel; /** * Launch the application. */ public static void main(String[] args) { EventQueue.invokeLater(new Runnable() { public void run() { try { mgfinancewindow window = new mgfinancewindow(); window.frame.setVisible(true); } catch (Exception e) { e.printStackTrace(); } } }); } /** * Create the application. */ public mgfinancewindow() { initialize(); } /** * Initialize the contents of the frame. */ private void initialize() { frame = new JFrame("MG Finances"); frame.setBounds(100, 100, 450, 300); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); frame.setExtendedState(JFrame.MAXIMIZED_BOTH); frame.getContentPane().setLayout(null); JPanel panel = new JPanel(); panel.setBounds(0, 0, 1362, 705); frame.getContentPane().add(panel); panel.setLayout(null); JPanel panel_1 = new JPanel(); panel_1.setBackground(Color.DARK_GRAY); panel_1.setBounds(0, 646, 1362, 59); panel.add(panel_1); panel_1.setLayout(null); lblNewLabel = new JLabel("Loading..."); lblNewLabel.setFont(new Font("Tahoma", Font.BOLD | Font.ITALIC, 16)); lblNewLabel.setHorizontalAlignment(SwingConstants.CENTER); lblNewLabel.setForeground(Color.WHITE); lblNewLabel.setBounds(1139, 0, 114, 34); panel_1.add(lblNewLabel); progressBar = new JProgressBar(); progressBar.setBackground(new Color(0, 51, 51)); progressBar.setBounds(0, 34, 1362, 14); panel_1.add(progressBar); JLabel lblMgFinance = new JLabel("MG Finance"); lblMgFinance.setHorizontalAlignment(SwingConstants.CENTER); lblMgFinance.setFont(new Font("Tahoma", Font.BOLD | Font.ITALIC, 16)); lblMgFinance.setForeground(Color.BLUE); lblMgFinance.setBounds(0, 11, 1362, 635); panel.add(lblMgFinance); frame.setVisible(true); } }这样在内部创建mgfinancewindow的组件时，大多数时候最好从JFrame 扩展然后您可以从中创建一个对象，并在程序的main方法中调用JFrame方法。最好不要在该组件中调用setVisible，因为在另一个类中，有时您想要创建并初始化setVisible，但您不希望立即显示它。

另一个提示：

根据 Java编码约定：

您的班级名称必须遵循 CamelCase 样式。
变量名必须遵循 camelCase （小写的第一个字母）样式。

您可能需要查看其他java编码约定here。

进度条加载不起作用

1 个答案: