消除Borderlayout中Jpanel之间的差距

Question

我将2 JPanel（中心和page_end）添加到Jframe中的另一个JPanel。我想消除两个面板（paneaudatedebut和panneaudatefin）之间存在巨大差距。我试图将它们设置为不同的配置（开始/中心，开始/结束，中心/结束），但没有运气。如何才能做到这一点 ？

编辑要有一个工作代码

import java.awt.BorderLayout;
import java.awt.ComponentOrientation;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.Frame;
import java.awt.GridLayout;
import javax.swing.JButton;
import javax.swing.JComboBox;
import javax.swing.JDialog;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextField;
public class CreerModificationAbsence extends JDialog {
    private JPanel modificationAbsence1, modificationAbsence2,
            modificationAbsence3, panneauDateDebut, panneauDateFin;
    private JButton modifier, annuler;
    private JLabel raison, prenomNomEmpl, prenomNomChef;
    private JComboBox<String> raisonC, heureDebutC, heureFinC, minuteDebutC,
            minuteFinC;
    private JTextField prenomNomEmplT, prenomnomChefT;
    private final String[] raisonAbsence = { "Malade" };
    private JLabel dateDebut, dateFin;
    private JTextField dateDebutT, dateFinT;
    private final String[] heures = { "00" };
    private final String[] minutes = { "00", "15", "30", "45" };
    private BorderLayout gestionnaireComposant;
    private GridLayout gridGestionnaireComposant;
    private FlowLayout panneauMilieuLayout;
    final FlowLayout gestionnaireComposantBas;
    public CreerModificationAbsence() {
        super((Frame) null, "Modification - Absence d'employé", true);
        setPreferredSize(new Dimension(600, 250));
        setAlwaysOnTop(true);
        setResizable(false);
        setLocation(400, 200);
        setAlwaysOnTop(true);
        gestionnaireComposant = new BorderLayout();
        this.getContentPane().setLayout(gestionnaireComposant);
        // Modification Panneau Haut
        modificationAbsence1 = new JPanel();
        gridGestionnaireComposant = new GridLayout(3, 2, 2, 2);
        modificationAbsence1.setLayout(gridGestionnaireComposant);
        raison = new JLabel("Raison : ");
        raisonC = new JComboBox<>(raisonAbsence);
        raisonC.setEditable(true);
        prenomNomEmpl = new JLabel("Prénom et Nom de l'employé : ");
        prenomNomEmplT = new JTextField();
        prenomNomChef = new JLabel("Prénom et Nom du chef d'équipe : ");
        prenomnomChefT = new JTextField();
        modificationAbsence1.add(raison);
        modificationAbsence1.add(raisonC);
        modificationAbsence1.add(prenomNomEmpl);
        modificationAbsence1.add(prenomNomEmplT);
        modificationAbsence1.add(prenomNomChef);
        modificationAbsence1.add(prenomnomChefT);
        // Modification Panneau Milieu
        modificationAbsence2 = new JPanel();
        panneauDateDebut = new JPanel();
        panneauDateFin = new JPanel();
        panneauMilieuLayout = new FlowLayout();
        panneauDateDebut.setLayout(panneauMilieuLayout);
        panneauDateDebut.setPreferredSize(new Dimension(600, 0));
                   panneauDateDebut.setComponentOrientation(ComponentOrientation.LEFT_TO_RIGHT);
        panneauDateFin.setLayout(panneauMilieuLayout);
        panneauDateFin.setComponentOrientation(ComponentOrientation.LEFT_TO_RIGHT);
        panneauDateFin.setPreferredSize(new Dimension(600, 113));
        modificationAbsence2.setLayout(new BorderLayout(0,0));
        dateDebutT = new JTextField(12);
        heureDebutC = new JComboBox<>(heures);
        minuteDebutC = new JComboBox<>(minutes);
        dateFinT = new JTextField(12);
        heureFinC = new JComboBox<>(heures);
        minuteFinC = new JComboBox<>(minutes);
        dateDebut = new JLabel("Date de début :");
        dateFin = new JLabel("Date de fin :");
        dateDebutT.setPreferredSize(new Dimension(125, 20));
        dateFinT.setPreferredSize(new Dimension(125, 20));
        dateDebut.setPreferredSize(new Dimension(125, 20));
        dateFin.setPreferredSize(new Dimension(125, 20));
        heureDebutC.setPreferredSize(new Dimension(130, 20));
        minuteDebutC.setPreferredSize(new Dimension(130, 20));
        heureFinC.setPreferredSize(new Dimension(130, 20));
        minuteFinC.setPreferredSize(new Dimension(130, 20));
        panneauDateDebut.add(dateDebut);
        panneauDateDebut.add(dateDebutT);
        panneauDateDebut.add(heureDebutC);
        panneauDateDebut.add(minuteDebutC);
        panneauDateFin.add(dateFin);
        panneauDateFin.add(dateFinT);
        panneauDateFin.add(heureFinC);
        panneauDateFin.add(minuteFinC);
        modificationAbsence2.add(panneauDateDebut, BorderLayout.CENTER);
        modificationAbsence2.add(panneauDateFin, BorderLayout.PAGE_END);
        // Modification Panneau Bas
        modificationAbsence3 = new JPanel();
        gestionnaireComposantBas = new FlowLayout(FlowLayout.RIGHT);
        modificationAbsence3.setLayout(gestionnaireComposantBas);
        modifier = new JButton("Modifier");
        annuler = new JButton("Annuler");
        modificationAbsence3.add(modifier);
        modificationAbsence3.add(annuler);
        this.add(modificationAbsence1, BorderLayout.NORTH);
        this.add(modificationAbsence2, BorderLayout.CENTER);
        this.add(modificationAbsence3, BorderLayout.SOUTH);
        /*this.*/setDefaultCloseOperation(DISPOSE_ON_CLOSE);
        this.pack();
            /*this.*/setVisible(true);
    }
 public static void main(String s[]) {
    SwingUtilities.invokeLater(new Runnable() {
        @Override
        public void run() {
            CreerModificationAbsence textf = new CreerModificationAbsence();
        }
    });
}

}

Answer 1

对于初学者来说（对于恩德斯来说，不知道这是英语）：不要致电 setPreferredSize()！这就是导致您所有问题的原因。停止使用它（永远在您的生活中〜不好的幽默感，不要苛刻），您将解决所有问题。

而是尝试一下：

import java.awt.BorderLayout;
import java.awt.ComponentOrientation;
import java.awt.FlowLayout;
import java.awt.Frame;
import java.awt.GridLayout;
import javax.swing.JButton;
import javax.swing.JComboBox;
import javax.swing.JDialog;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.SwingUtilities;
public class CreerModificationAbsence extends JDialog {
    private JPanel modificationAbsence1, modificationAbsence2, modificationAbsence3, panneauDateDebut, panneauDateFin;
    private JButton modifier, annuler;
    private JLabel raison, prenomNomEmpl, prenomNomChef;
    private JComboBox<String> raisonC, heureDebutC, heureFinC, minuteDebutC, minuteFinC;
    private JTextField prenomNomEmplT, prenomnomChefT;
    private final String[] raisonAbsence = { "Malade" };
    private JLabel dateDebut, dateFin;
    private JTextField dateDebutT, dateFinT;
    private final String[] heures = { "00" };
    private final String[] minutes = { "00", "15", "30", "45" };
    private BorderLayout gestionnaireComposant;
    private GridLayout gridGestionnaireComposant;
    private FlowLayout panneauMilieuLayout;
    final FlowLayout gestionnaireComposantBas;
    public CreerModificationAbsence() {
        super((Frame) null, "Modification - Absence d'employé", true);
        // setPreferredSize(new Dimension(600, 250));
        setAlwaysOnTop(true);
        setResizable(false);
        setAlwaysOnTop(true);
        gestionnaireComposant = new BorderLayout();
        this.getContentPane().setLayout(gestionnaireComposant);
        // Modification Panneau Haut
        modificationAbsence1 = new JPanel();
        gridGestionnaireComposant = new GridLayout(3, 2, 2, 2);
        modificationAbsence1.setLayout(gridGestionnaireComposant);
        raison = new JLabel("Raison : ");
        raisonC = new JComboBox(raisonAbsence);
        raisonC.setEditable(true);
        prenomNomEmpl = new JLabel("Prénom et Nom de l'employé : ");
        prenomNomEmplT = new JTextField();
        prenomNomChef = new JLabel("Prénom et Nom du chef d'équipe : ");
        prenomnomChefT = new JTextField();
        modificationAbsence1.add(raison);
        modificationAbsence1.add(raisonC);
        modificationAbsence1.add(prenomNomEmpl);
        modificationAbsence1.add(prenomNomEmplT);
        modificationAbsence1.add(prenomNomChef);
        modificationAbsence1.add(prenomnomChefT);
        // Modification Panneau Milieu
        modificationAbsence2 = new JPanel();
        panneauDateDebut = new JPanel();
        panneauDateFin = new JPanel();
        panneauMilieuLayout = new FlowLayout();
        panneauDateDebut.setLayout(panneauMilieuLayout);
        panneauDateDebut.setComponentOrientation(ComponentOrientation.LEFT_TO_RIGHT);
        panneauDateFin.setLayout(panneauMilieuLayout);
        panneauDateFin.setComponentOrientation(ComponentOrientation.LEFT_TO_RIGHT);
        dateDebutT = new JTextField(12);
        heureDebutC = new JComboBox(heures);
        minuteDebutC = new JComboBox(minutes);
        dateFinT = new JTextField(12);
        heureFinC = new JComboBox(heures);
        minuteFinC = new JComboBox(minutes);
        dateDebut = new JLabel("Date de début :");
        dateFin = new JLabel("Date de fin :");
        panneauDateDebut.add(dateDebut);
        panneauDateDebut.add(dateDebutT);
        panneauDateDebut.add(heureDebutC);
        panneauDateDebut.add(minuteDebutC);
        panneauDateFin.add(dateFin);
        panneauDateFin.add(dateFinT);
        panneauDateFin.add(heureFinC);
        panneauDateFin.add(minuteFinC);
        modificationAbsence2.add(panneauDateDebut, BorderLayout.CENTER);
        modificationAbsence2.add(panneauDateFin, BorderLayout.PAGE_END);
        // Modification Panneau Bas
        modificationAbsence3 = new JPanel();
        gestionnaireComposantBas = new FlowLayout(FlowLayout.RIGHT);
        modificationAbsence3.setLayout(gestionnaireComposantBas);
        modifier = new JButton("Modifier");
        annuler = new JButton("Annuler");
        modificationAbsence3.add(modifier);
        modificationAbsence3.add(annuler);
        this.add(modificationAbsence1, BorderLayout.NORTH);
        this.add(modificationAbsence2, BorderLayout.CENTER);
        this.add(modificationAbsence3, BorderLayout.SOUTH);
        /*this.*/setDefaultCloseOperation(DISPOSE_ON_CLOSE);
        this.pack();
        setLocationRelativeTo(null);
        /*this.*/setVisible(true);
    }
    public static void main(String s[]) {
        SwingUtilities.invokeLater(new Runnable() {
            @Override
            public void run() {
                CreerModificationAbsence textf = new CreerModificationAbsence();
            }
        });
    }
}

Answer 2

您遇到的问题是因为您在JDialog上使用了setPreferredSize。因此，发生的是对话框必须为给定的大小。因为现在具有是这样的大小，所以必须给出一些大小。这就是Layoutmanagers接管的地方。在Borderlayout中，中间的任何内容都将始终伸展。

如果您设置了两个面板的背景，您可以看到发生了什么事：

    panneauDateDebut = new JPanel();
    panneauDateDebut.setOpaque(true);
    panneauDateDebut.setBackground(Color.blue);
    panneauDateFin = new JPanel();
    panneauDateFin.setOpaque(true);
    panneauDateFin.setBackground(Color.green);

解决方案（Guillaume在写作时指出的是）是停止使用setPreferredSize。因此，如果您的构造函数看起来如下，则应解决问题：

public PageCentering() {
        super((Frame) null, "Modification - Absence d'employé", true);
        //setPreferredSize(new Dimension(600, 250));
        ...
}