4 课后答案【khdaw_lxywyl】(17)

new Test4_12(); } }

【13】创建一个输入对话框，从对话框中输入文字，当按下“确定”按钮后，能在屏幕上显示输入的文字。

[解答]：Test4_13.java

import java.awt.*;

import java.awt.event.*;

class Test4_13 extends Frame implements ActionListener{ TextArea txtAr; Button btn1; public Test4_13(){ super("对话框练习"); setSize(300,400); setVisible(true); setLayout(new BorderLayout()); btn1=new Button("打开对话框"); txtAr=new TextArea(8,10); add("North",btn1); add("Center",txtAr); validate(); addWindowListener(new WindowAdapter(){ public void windowClosing(WindowEvent we){ System.exit(0); }} ); btn1.addActionListener(this); }

public void actionPerformed(ActionEvent e){ DiaObj dia=new DiaObj(this,txtAr); //声明和实例话对话框,传递frame,和txtar参数 }

public static void main(String[] args){ new Test4_13(); } }

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