java - 如何在 gridbaglayout 中更改网格的最小高度

Question

我在这里使用面板上的 gridbag 布局来添加 5 行排列的 5 个组件，我希望它们具有不同的高度 like this但是在这样做之后

public void mainpanel3(){

   pupper.setBackground(Color.yellow);
   ptable.setBackground(Color.BLACK);
   lthird.setOpaque(true);
   lthird.setBackground(Color.BLUE);
   tffourth.setBackground(Color.GREEN);
   pfifth.setBackground(Color.WHITE);


   outerp3.setLayout(new GridBagLayout());
   GridBagConstraints c=new GridBagConstraints();


   c.weightx=0.5;
   c.weighty=0.5;
   c.fill=GridBagConstraints.BOTH;

   c.weightx=0.5;
   c.weighty=0.1;
   c.ipady=5;
   c.gridx=0;
   c.gridy=0;       
   outerp3.add(pupper,c);

   c.weightx=0.5;
   c.weighty=0.4;
   c.ipady=20;
   c.gridx=0;
   c.gridy=1;
   outerp3.add(ptable,c);

   c.weightx=0.5;
   c.weighty=0.1;
   c.ipady=5;
   c.gridx=0;
   c.gridy=2;
   outerp3.add(lthird,c);

   c.weightx=0.5;
   c.weighty=0.1;
   c.ipady=5;
   c.gridx=0;
   c.gridy=3;
   outerp3.add(tffourth,c);

   c.weightx=0.5;
   c.weighty=0.1;
   c.ipady=5;
   c.gridx=0;
   c.gridy=4;
   outerp3.add(pfifth,c);

    }

这会发生

output

第五个组件(面板)白色没有出现。

有关此面板的编码仅在此方法中完成，如果您需要任何其他代码，请告诉我。

Answer 1

您需要指定 weighty 值，尽管每个组件的 weightx 始终是 1.0，因为每个组件仅在它的高度 但不是宽度。这是一个工作示例:

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

public class GridBagLayoutExample {

    private GridBagConstraints m_GBC;

    public GridBagLayoutExample () {
        m_GBC = new GridBagConstraints ();
        m_GBC.anchor = GridBagConstraints.FIRST_LINE_START;
        m_GBC.fill = GridBagConstraints.BOTH;
    }

    private void displayGUI () {
        JFrame frame = new JFrame ( "GridBagLayout Example" );
        frame.setDefaultCloseOperation ( JFrame.DISPOSE_ON_CLOSE );

        JPanel contentPane = new JPanel ();
        contentPane.setLayout ( new GridBagLayout () );

        addComponent ( contentPane, getPanel (), 0, 0, 1, 1, 1.0, 0.1 );
        addComponent ( contentPane, getPanel (), 0, 1, 1, 5, 1.0, 0.5 );
        addComponent ( contentPane, getPanel (), 0, 6, 1, 1, 1.0, 0.1 );
        addComponent ( contentPane, getPanel (), 0, 7, 1, 2, 1.0, 0.2 );
        addComponent ( contentPane, getPanel (), 0, 9, 1, 1, 1.0, 0.1 );

        frame.setContentPane ( contentPane );
        frame.pack ();
        frame.setLocationByPlatform ( true );
        frame.setVisible ( true );
    }

    private void addComponent ( JComponent contentPane, JComponent component,
                                int x, int y, int gridwidth, int gridheight,
                                double weightx, double weighty ) {
        m_GBC.gridx = x;
        m_GBC.gridy = y;
        m_GBC.gridwidth = gridwidth;
        m_GBC.gridheight = gridheight;
        m_GBC.weightx = weightx;
        m_GBC.weighty = weighty;

        contentPane.add ( component, m_GBC );
    }

    private JPanel getPanel () {
        JPanel panel = new JPanel ();
        panel.setOpaque ( true );
        Color color = new Color ( ( float ) Math.random (), ( float ) Math.random (),
                                ( float ) Math.random (), ( float ) Math.random () );
        panel.setBackground ( color );

        return panel;
    }

    public static void main ( String [] args ) {
        Runnable runnable = new Runnable () {
            @Override
            public void run () {
                new GridBagLayoutExample ().displayGUI ();
            }
        };
        EventQueue.invokeLater ( runnable );
    }
}

输出