将多个 Jtextareas 添加到同一个 JScrollPane

Question

我知道有很多关于它的问题，但我都阅读了所有问题。大多数人更喜欢将文本区域添加到面板中并将此面板添加到 JScrollPane 中。我试过了，但没用。

这是我的代码。

AppSed Class

package gui;

import javax.swing.SwingUtilities;

public class AppSed {

public static void main(String[] args){

SwingUtilities.invokeLater(new Runnable(){
    public void run(){

        new MainFrame();
    }
    });
}
}

主机Class

package gui;

import java.awt.BorderLayout;

import javax.swing.JFrame;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;

public class MainFrame extends JFrame {

private TextPanel textPanel;
private ToolBar toolBar;

public MainFrame(){
    super("Sed Debugger");

    setLayout(new BorderLayout());

    textPanel = new TextPanel();
    toolBar = new ToolBar();
    add(textPanel,BorderLayout.CENTER );
    add(toolBar, BorderLayout.NORTH);

    setJMenuBar(createMenuBar());
    setSize(1200,800);
    setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    setVisible(true);
}
public JMenuBar createMenuBar(){
     JMenuBar menuBar = new JMenuBar();

     JMenu file = new JMenu("File");
     JMenu debug = new JMenu("Debug");
     JMenu help = new JMenu("Help");

     JMenuItem newFile = new JMenuItem("New");
     JMenuItem saveFile = new JMenuItem("Open");
     JMenuItem openFile = new JMenuItem("Save");
     JMenuItem exit = new JMenuItem("Exit");

     file.add(newFile);
     file.add(openFile);
     file.add(saveFile);
     file.add(exit);

     JMenuItem run = new JMenuItem("Run");
     JMenuItem stop = new JMenuItem("Stop");
     JMenuItem refresh = new JMenuItem("Refresh");
     JMenuItem stepIn = new JMenuItem("Step In");
     JMenuItem stepOut = new JMenuItem("Step Out");
     JMenuItem stepOver = new JMenuItem("Step Over");
     JMenuItem breakPoint = new JMenuItem("New Breakpoint");

     debug.add(run);
     debug.add(stop);
     debug.add(refresh);
     debug.add(stepIn);
     debug.add(stepOut);
     debug.add(stepOver);
     debug.add(breakPoint);

     JMenuItem commentHelp = new JMenuItem("Comment Help");
     JMenuItem about = new JMenuItem("About");

     help.add(commentHelp);
     help.add(about);

     menuBar.add(file);
     menuBar.add(debug);
     menuBar.add(help);

     return menuBar;
}
}

文本面板class

package gui;

import java.awt.Dimension;
public class TextPanel extends JPanel {
private InputPane input ; 
private JScrollPane scrollPane;

public TextPanel(){

    setLayout(new GridBagLayout());

    input = new InputPane();
    scrollPane = new JScrollPane(input);

    Dimension dim = scrollPane.getPreferredSize();
    dim.width = 510;
    dim.height = 290;
    scrollPane.setPreferredSize(dim);

    GridBagConstraints gc = new GridBagConstraints();

    gc.gridx = 0;
    gc.gridy = 0;
    gc.weightx = 0.25;

    add(scrollPane,gc);

}
}

输入面板class

package gui;

import java.awt.BorderLayout...;


public class InputPane extends JPanel {

private JTextArea inputText;
private JTextArea lineNumber;
private JScrollPane scrollPane;

public InputPane(){

    setLayout(new BorderLayout());

    Dimension dim = getPreferredSize();
    dim.width  = 500;
    dim.height = 250;
    setPreferredSize(dim);

    setBorder(BorderFactory.createTitledBorder("Original File"));

    inputText = new JTextArea();
    lineNumber = new JTextArea();

    Dimension dimInput = getPreferredSize();
    dimInput.width = 440;
    dimInput.height = 250;
    inputText.setPreferredSize(dimInput);

    Dimension lineDim = getPreferredSize();
    lineDim.width = 50;
    lineDim.height = 250;
    lineNumber.setPreferredSize(lineDim);
    lineNumber.setBorder(BorderFactory.createMatteBorder(0, 0, 0, 2,             Color.gray));

    add(inputText,BorderLayout.EAST);
    add(lineNumber,BorderLayout.WEST);

}

Answer 1

inputText = new JTextArea();
lineNumber = new JTextArea();

我认为您应该将行号 textarea 添加到滚动窗格的行 header，而不是在面板上使用两个文本区域。另外，不要使用 setPreferredSize()。它默认使用滚动窗格的目的，因为只有当组件的首选大小大于滚动窗格的大小时，滚动条才会出现。

您可能想要查看 Text Component Line Number，而不是使用两个文本区域，它旨在在文本组件旁边显示行号。行号组件添加到滚动窗格的行 header。

Answer 2

您 "seem" 想创建一个 "split" 行号在左边，文本在右边？

第一步，停止与组件的preferredSize拧紧。您无法控制这些组件需要用来计算其需求的因素。

有关详细信息，请参阅 Should I avoid the use of set(Preferred|Maximum|Minimum)Size methods in Java Swing?

相反，使用可用的属性提供提示，这可以让他们计算出他们需要space的数量

查看 JTextArea(int, int) 了解更多详情

例如...

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import javax.swing.BorderFactory;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;

public class Test {

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

    public Test() {
        EventQueue.invokeLater(new Runnable() {
            @Override
            public void run() {
                try {
                    UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
                } catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
                    ex.printStackTrace();
                }

                JFrame frame = new JFrame("Testing");
                frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                frame.add(new TextPanel());
                frame.pack();
                frame.setLocationRelativeTo(null);
                frame.setVisible(true);
            }
        });
    }

    public class TextPanel extends JPanel {

        private InputPane input;
        private JScrollPane scrollPane;

        public TextPanel() {

            setLayout(new GridBagLayout());

            input = new InputPane();
            scrollPane = new JScrollPane(input);

            GridBagConstraints gc = new GridBagConstraints();

            gc.gridx = 0;
            gc.gridy = 0;
            gc.weightx = 0.25;

            add(scrollPane, gc);

        }
    }

    public class InputPane extends JPanel {

        private JTextArea inputText;
        private JTextArea lineNumber;

        public InputPane() {

            setLayout(new BorderLayout());

            setBorder(BorderFactory.createTitledBorder("Original File"));

            inputText = new JTextArea(10, 20);
            lineNumber = new JTextArea(10, 4);

            lineNumber.setBorder(BorderFactory.createMatteBorder(0, 0, 0, 2, Color.gray));

            add(inputText);
            add(lineNumber, BorderLayout.WEST);

        }
    }
}

现在，话虽如此，我不鼓励您使用此过程，并建议改用 JScrollPane#setRowHeaderView。有关详细信息，请参阅 this example and How to Use Scroll Panes

将多个 Jtextareas 添加到同一个 JScrollPane

Adding multiple Jtextareas into same JScrollPane

java

user-interface

swing

jscrollpane