设置按钮的大小和位置

Question

有两个按钮

    left = new JButton("prev");
    right = new JButton("next");

我像这样将它们添加到 jframe

    mainframe.add(left,BorderLayout.WEST);
    mainframe.add(right,BorderLayout.EAST);

但是有高度与主机的高度相同。如何设置自己的宽高？

以及如何设置他们的位置（不仅在NORTH，WEST，EAST，SOUTH）？

Answer 1

如何设置自己的宽高

不要那样做，而是使用 JPanel 的 NORTH 或 SOUTH 来限制大小，而 JPanel 本身会添加到外部（父）布局的 EAST 或 WEST。

很像这样：

import java.awt.*;
import javax.swing.*;

class BorderGUI {

    BorderGUI() {
        JPanel gui = new JPanel(new BorderLayout(2,2));

        JPanel westConstrain = new JPanel(new BorderLayout(2,2));
        // LINE_START will be WEST for l-r languages, otherwise EAST
        gui.add(westConstrain, BorderLayout.LINE_START);

        JPanel westControls = new JPanel(new GridLayout(0,1,2,2));
        for (int ii=1; ii<3; ii++) {
            westControls.add( new JButton("" + ii) );
        }
        westConstrain.add(westControls, BorderLayout.PAGE_START);

        JPanel eastConstrain = new JPanel(new BorderLayout(2,2));
        gui.add(eastConstrain, BorderLayout.LINE_END);

        JPanel eastControls = new JPanel(new GridLayout(0,1,2,2));
        for (int ii=1; ii<4; ii++) {
            eastControls.add( new JButton("" + ii) );
        }
        // show at the bottom
        eastConstrain.add(eastControls, BorderLayout.PAGE_END);

        gui.add( new JScrollPane(new JTextArea(6,10)), BorderLayout.CENTER );

        JOptionPane.showMessageDialog(null, gui);
    }

    public static void main(String[] args) {
        EventQueue.invokeLater(new Runnable() {

            @Override
            public void run() {
                new BorderGUI();
            }
        });
    }
}