请教Java Swing中JTextarea问题

Question

请问如果控制JTextArea，使其弹出的时候窗口不超过屏幕之外。

Answer 1

简单的例子

[code="java"]
import java.awt.BorderLayout;
import java.awt.Frame;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.JButton;
import javax.swing.JDialog;
import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;

public class TextareaTest {

public static void main(String[] args) {

    final JFrame frame = new JFrame("Textarea");
    final JDialog dialog = new TextareaDialog(frame, true);

    JButton button = new JButton("Click Me!");
    button.addActionListener(new ActionListener() {

        @Override
        public void actionPerformed(ActionEvent e) {
            dialog.setLocationRelativeTo(frame);
            dialog.pack();
            dialog.setSize(300, 200);
            dialog.setVisible(true);
        }
    });
    frame.getContentPane().add(button, BorderLayout.CENTER);

    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    frame.setLocationRelativeTo(null);
    frame.pack();
    frame.setVisible(true);
}

}

class TextareaDialog extends JDialog {

JTextArea textarea = new JTextArea();

public TextareaDialog(Frame owner, boolean modal) {
    super(owner, modal);

    // 初始化
    setDefaultCloseOperation(JDialog.DISPOSE_ON_CLOSE);
    setTitle("文本框测试");

    // 添加文本框。
    textarea.setLineWrap(true);
    JScrollPane scroll = new JScrollPane(textarea);
    getContentPane().add(scroll, BorderLayout.CENTER);

    // ====-------------------------------测试数据。
    String text = "长长的测试数据";
    for (int i = 0; i <= 1000; i++) {
        text += "好长";
    }
    textarea.setText(text);
}

}
[/code]