JFrame.setExtendedState（）在Mac上无法正常工作

Question

我正在使用带有java 1.8.0_211的javax.swing.JFrame，我希望在整个屏幕上最大化我的JFrame。

我使用以下代码：

public class MitarbeiterUI extends javax.swing.JFrame {


    /**
     * Creates new form MitarbeiterUI
     */
    public MitarbeiterUI(Mitarbeiter mitarbt) {

        initComponents();

        this.setExtendedState(MAXIMIZED_BOTH);
        this.setSize((int)Toolkit.getDefaultToolkit().getScreenSize().getWidth(), (int)Toolkit.getDefaultToolkit().getScreenSize().getHeight());
        this.setVisible(true);
    }

    [...]
}

但是这只会使窗口水平对齐屏幕，而不是垂直对齐。 它适用于Windows和Linux系统，因此它必须是Mac特定的问题。 围绕这个强大的烦人的bug有什么办法吗？

编辑：可执行代码示例

import java.awt.Toolkit;

public class SecondFrame extends javax.swing.JFrame {

/**
 * Creates new form SecondFrame
 */
public SecondFrame() {
    initComponents();

    this.setExtendedState(MAXIMIZED_BOTH);
    this.setSize((int)Toolkit.getDefaultToolkit().getScreenSize().getWidth(), (int)Toolkit.getDefaultToolkit().getScreenSize().getHeight());
    this.setVisible(true);
}

/**
 * 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() {

    jPanel1 = new javax.swing.JPanel();
    jLabel1 = new javax.swing.JLabel();

    setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
    addComponentListener(new java.awt.event.ComponentAdapter() {
        public void componentResized(java.awt.event.ComponentEvent evt) {
            formComponentResized(evt);
        }
    });

    jPanel1.setBorder(javax.swing.BorderFactory.createBevelBorder(javax.swing.border.BevelBorder.RAISED));

    javax.swing.GroupLayout jPanel1Layout = new javax.swing.GroupLayout(jPanel1);
    jPanel1.setLayout(jPanel1Layout);
    jPanel1Layout.setHorizontalGroup(
        jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
        .addGap(0, 563, Short.MAX_VALUE)
    );
    jPanel1Layout.setVerticalGroup(
        jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
        .addGap(0, 877, Short.MAX_VALUE)
    );

    javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
    getContentPane().setLayout(layout);
    layout.setHorizontalGroup(
        layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
        .addGroup(layout.createSequentialGroup()
            .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                .addGroup(layout.createSequentialGroup()
                    .addGap(134, 134, 134)
                    .addComponent(jPanel1, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE))
                .addGroup(layout.createSequentialGroup()
                    .addContainerGap()
                    .addComponent(jLabel1)))
            .addContainerGap(25, Short.MAX_VALUE))
    );
    layout.setVerticalGroup(
        layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
        .addGroup(layout.createSequentialGroup()
            .addContainerGap()
            .addComponent(jLabel1)
            .addGap(19, 19, 19)
            .addComponent(jPanel1, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
            .addContainerGap(241, Short.MAX_VALUE))
    );

    pack();
}// </editor-fold>                        

private void formComponentResized(java.awt.event.ComponentEvent evt) {                                      
    jLabel1.setText("W: " + this.getWidth() + ", H: " + this.getHeight());
}                                     

/**
 * @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(SecondFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
    } catch (InstantiationException ex) {
        java.util.logging.Logger.getLogger(SecondFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
    } catch (IllegalAccessException ex) {
        java.util.logging.Logger.getLogger(SecondFrame.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
    } catch (javax.swing.UnsupportedLookAndFeelException ex) {
        java.util.logging.Logger.getLogger(SecondFrame.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 SecondFrame().setVisible(true);
        }
    });
}

// Variables declaration - do not modify                     
private javax.swing.JLabel jLabel1;
private javax.swing.JPanel jPanel1;
// End of variables declaration                   
}

编辑2：似乎问题在于我们使用的Mac的屏幕尺寸。 它们的分辨率都高于全高清，但两者都会自动缩小到1440到900p，这使得我们在我们班级使用的JPanel比调整大小的屏幕大，反过来又在底部切断。 所以我想问题是现在我怎么能告诉那些Mac不调整屏幕大小，或者如何将滚动条添加到JFrame而不必重做整个类。

Answer 1

this.setExtendedState(MAXIMIZED_BOTH);
this.setSize((int)Toolkit.getDefaultToolkit().getScreenSize().getWidth(), (int)Toolkit.getDefaultToolkit().getScreenSize().getHeight());
this.setVisible(true);

使用setExtendedState(...)是你不需要使用setSize（...）方法。

所以代码应该只是：

this.setExtendedState(MAXIMIZED_BOTH);
this.setVisible(true);

setSize（）语句将覆盖setExtendedState（...）方法计算的大小。