Question

我想创建一个由4个组件组成的JPanel，分为2列。左列的上部组件应占垂直空间的60％，下部组件的剩余部分占40％。在右栏中，它应该是相反的 - 上部组件需要40％而下部组件需要60％。

所以基本上我想把我的组件放在这张照片上：

我试图用GridBagLayout来实现这种行为。

public class Test extends JFrame {
JPanel testPanel = new JPanel();

public static void main(String[] args) {
    SwingUtilities.invokeLater(() -> {
        new Test().setVisible(true);
    });
}

Test() {
    prepareTestPanel();
    setContentPane(testPanel);
    setSize(500, 500);
    setTitle("Test");
    setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}

private void prepareTestPanel() {
    testPanel.setLayout(new GridBagLayout());
    addComp(makeUpperLeft());
    addComp(makeLowerLeft());
    addComp(makeUpperRight());
    addComp(makeLowerRight());
}

private void addComp(Pair p) {
    testPanel.add(p.comp, p.gbc);
}

private Pair makeUpperLeft() {
    JPanel panel = new JPanel();
    panel.setBorder(BorderFactory.createTitledBorder("Upper Left"));

    GridBagConstraints gbc = new GridBagConstraints();
    gbc.gridx = 0;
    gbc.gridy = 0;
    gbc.gridheight = 60;
    gbc.gridwidth = 50;
    gbc.fill = GridBagConstraints.BOTH;
    gbc.anchor = GridBagConstraints.LINE_START;
    gbc.weightx = 0.5;
    gbc.weighty = 0.6;

    return new Pair(panel, gbc);
}

private Pair makeLowerLeft() {
    JPanel panel = new JPanel();
    panel.setBorder(BorderFactory.createTitledBorder("Lower Left"));

    GridBagConstraints gbc = new GridBagConstraints();
    gbc.gridx = 0;
    gbc.gridy = 60;
    gbc.gridheight = 40;
    gbc.gridwidth = 50;
    gbc.fill = GridBagConstraints.BOTH;
    gbc.anchor = GridBagConstraints.LINE_START;
    gbc.weightx = 0.5;
    gbc.weighty = 0.4;

    return new Pair(panel, gbc);
}

private Pair makeUpperRight() {
    JPanel panel = new JPanel();
    panel.setBorder(BorderFactory.createTitledBorder("Upper Right"));

    GridBagConstraints gbc = new GridBagConstraints();
    gbc.gridx = 50;
    gbc.gridy = 0;
    gbc.gridheight = 40;
    gbc.gridwidth = 50;
    gbc.fill = GridBagConstraints.BOTH;
    gbc.anchor = GridBagConstraints.LINE_START;
    gbc.weightx = 0.5;
    gbc.weighty = 0.4;

    return new Pair(panel, gbc);
}

private Pair makeLowerRight() {
    JPanel panel = new JPanel();
    panel.setBorder(BorderFactory.createTitledBorder("Lower Right"));

    GridBagConstraints gbc = new GridBagConstraints();
    gbc.gridx = 50;
    gbc.gridy = 40;
    gbc.gridheight = 60;
    gbc.gridwidth = 50;
    gbc.fill = GridBagConstraints.BOTH;
    gbc.anchor = GridBagConstraints.LINE_START;
    gbc.weightx = 0.5;
    gbc.weighty = 0.6;

    return new Pair(panel, gbc);
}


private class Pair {
    Component comp;
    GridBagConstraints gbc;

    public Pair(Component comp, GridBagConstraints gbc) {
        this.comp = comp;
        this.gbc = gbc;
    }
}
}

不幸的是，我得到的是：

我应该如何更正我的代码？此外，无论窗口的大小如何调整，我都希望保留这个比例。我该如何设置weighty？

Answer 1

GridBagLayout并不容易支持：

您无法以所需的比例指定网格宽度/高度。如果你想要6/4的比例，那么你实际上需要创建10个相同大小的虚拟组件，并首先将它们添加到面板中。然后你可以说一个组件的网格高度等于那些虚拟组件中的4个（或6个）。
在调整帧大小时，weightx / y约束仅适用于额外空间。因此，组件最初将按其首选尺寸进行包装，这意味着您还需要手动设置所需比例的首选尺寸。

您可以查看RelativeLayout。它允许您根据可用空间轻松创建相对大小的组件。

使用此布局的基本代码如下：

RelativeLayout rl = new RelativeLayout(RelativeLayout.Y_AXIS);
rl.setFill( true );
JPanel left = new JPanel( rl );
left.add(upperLeft, new Float(60));
left.add(lowerLeft, new Float(40));

// repeat above for the right panel

JPanel main = new JPanel( new GridLayout(0, 2) );
main.add(left);
main.add(right);

frame.add(main);

Answer 2

这不能直接在一个容器中完成。您必须为两个列创建两个容器元素（比如说两个JPanel对象）。在外部容器中添加列，然后在内部面板中添加组件。以下是一些代码：

public class Test extends JFrame {
public Test() {

    JPanel testPanel = new JPanel();
    setContentPane(testPanel);
    GridBagLayout gbl_testPanel = new GridBagLayout();
    gbl_testPanel.columnWidths = new int[]{0, 0};
    gbl_testPanel.rowHeights = new int[]{0};
    gbl_testPanel.columnWeights = new double[]{0.5, 0.5};
    gbl_testPanel.rowWeights = new double[]{1.0};
    testPanel.setLayout(gbl_testPanel);

    JPanel leftPanel = new JPanel();
    GridBagConstraints gbc_leftPanel = new GridBagConstraints();
    gbc_leftPanel.fill = GridBagConstraints.BOTH;
    gbc_leftPanel.insets = new Insets(0, 0, 0, 5);
    gbc_leftPanel.gridx = 0;
    gbc_leftPanel.gridy = 0;
    testPanel.add(leftPanel, gbc_leftPanel);
    GridBagLayout gbl_leftPanel = new GridBagLayout();
    gbl_leftPanel.columnWidths = new int[]{0};
    gbl_leftPanel.rowHeights = new int[]{0, 0};
    gbl_leftPanel.columnWeights = new double[]{0.0};
    gbl_leftPanel.rowWeights = new double[]{0.6, 0.4};
    leftPanel.setLayout(gbl_leftPanel);

    JLabel lbl00 = new JLabel("Upper Left");
    GridBagConstraints gbc_lbl00 = new GridBagConstraints();
    gbc_lbl00.anchor = GridBagConstraints.NORTH;
    gbc_lbl00.fill = GridBagConstraints.HORIZONTAL;
    gbc_lbl00.insets = new Insets(0, 0, 5, 0);
    gbc_lbl00.gridx = 0;
    gbc_lbl00.gridy = 0;
    leftPanel.add(lbl00, gbc_lbl00);

    JLabel lbl10 = new JLabel("Lower Left");
    GridBagConstraints gbc_lbl10 = new GridBagConstraints();
    gbc_lbl10.anchor = GridBagConstraints.NORTH;
    gbc_lbl10.fill = GridBagConstraints.HORIZONTAL;
    gbc_lbl10.gridx = 0;
    gbc_lbl10.gridy = 1;
    leftPanel.add(lbl10, gbc_lbl10);

    JPanel rightPanel = new JPanel();
    GridBagConstraints gbc_rightPanel = new GridBagConstraints();
    gbc_rightPanel.fill = GridBagConstraints.BOTH;
    gbc_rightPanel.gridx = 1;
    gbc_rightPanel.gridy = 0;
    testPanel.add(rightPanel, gbc_rightPanel);
    GridBagLayout gbl_rightPanel = new GridBagLayout();
    gbl_rightPanel.columnWidths = new int[]{0};
    gbl_rightPanel.rowHeights = new int[]{0, 0};
    gbl_rightPanel.columnWeights = new double[]{0.0};
    gbl_rightPanel.rowWeights = new double[]{0.4, 0.6};
    rightPanel.setLayout(gbl_rightPanel);

    JLabel lbl01 = new JLabel("Upper Right");
    GridBagConstraints gbc_lbl01 = new GridBagConstraints();
    gbc_lbl01.insets = new Insets(0, 0, 5, 0);
    gbc_lbl01.fill = GridBagConstraints.HORIZONTAL;
    gbc_lbl01.anchor = GridBagConstraints.NORTH;
    gbc_lbl01.gridx = 0;
    gbc_lbl01.gridy = 0;
    rightPanel.add(lbl01, gbc_lbl01);

    JLabel lbl11 = new JLabel("Lower Right");
    GridBagConstraints gbc_lbl11 = new GridBagConstraints();
    gbc_lbl11.anchor = GridBagConstraints.NORTH;
    gbc_lbl11.fill = GridBagConstraints.HORIZONTAL;
    gbc_lbl11.gridx = 0;
    gbc_lbl11.gridy = 1;
    rightPanel.add(lbl11, gbc_lbl11);
}

}

GridBagLayout中的列数不均匀

2 个答案: