Question

我试图将JPanel中的一个部分包含在整个水平范围内的JTextPane中;但你可以看到它只是一个小裂缝。

为什么GridBagConstraints.HORIZONTALL填不起作用？

import java.awt.Dimension;

import java.awt.Font;
import java.awt.GridBagConstraints;
import java.awt.Insets;

import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JTextPane;
import javax.swing.text.SimpleAttributeSet;
import javax.swing.text.StyleConstants;
import javax.swing.text.StyledDocument;


public class TestJPanel extends JFrame{

    JTextPane crtAnswer;

    public static void main(String[] args){
        new TestJPanel();
    }

    TestJPanel(){
        //setup
        JPanel p = new JPanel();
        p.setLayout( new GridBagLayout());
        GridBagConstraints c = new GridBagConstraints();
        setLocation(200, 50);
        setPreferredSize(new Dimension(600, 674)); //width by height. (was 474,674) .. then (was 574,674)
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        pack();

        crtAnswer = new JTextPane(){
            public boolean isEditable(){ //don't let user edit label            
                return false;      
            };
        };
        crtAnswer.setAlignmentX(CENTER_ALIGNMENT);
        crtAnswer.setText("");
        crtAnswer.setFont(new Font("Arial", Font.BOLD, 22));

        //center text
        StyledDocument doc = crtAnswer.getStyledDocument();
        SimpleAttributeSet center = new SimpleAttributeSet();
        StyleConstants.setAlignment(center, StyleConstants.ALIGN_CENTER);
        doc.setParagraphAttributes(0, doc.getLength(), center, false);

        //constraints: crt answer
        c.fill = GridBagConstraints.HORIZONTAL;
        c.insets = new Insets(0,0, 5, 0);
        p.add(crtAnswer, c);


        add(p);
        setVisible(true);
    }
}

Answer 1

您尚未将p的布局设置为GridBagLayout。所以当然它不会起作用

JTextPane没有在GridBagConstraints上水平填充

1 个答案: