Question

t1.setText（将String.valueOf（V））;与t2.setText（String.valueOf（v））不是交互式的这里，如果我按下一个整数（两个它将显示前一个和当前整数）valueu t1不显示，但t2将给出数据变化的即时反映

import java.applet.*;
import java.awt.*;

import java.awt.event.*;

public class aacal extends Applet implements ActionListener{
    static int cv,pv,v,res;
    String cap; 
    Button b1=new Button("1");
    Button b2=new Button("2");
    Button b3=new Button("+");
    Button b4=new Button("=");
    TextField t1=new TextField(10);
    TextField t2=new TextField(10);
    public void init(){     
        // This textfield is to display the result and integer on buttons
        add(t1);
        t1.addActionListener(this);
        t1.setText("0");

        b1.addActionListener(this);
        add(b1);
        b2.addActionListener(this);
        add(b2);    
        b3.addActionListener(this);
        add(b3);        
        b4.addActionListener(this);
        add(b4);        
        //This textfield is to display the ActionCommand on buttons
        add(t2);
        t2.addActionListener(this);
        t2.setText("0");            
    }
    public void actionPerformed(ActionEvent ae){
        cap=ae.getActionCommand();  
        try{
            cv=Integer.parseInt(t2.getText());
            v=cv*10+Integer.parseInt(cap);          
            t2.setText(String.valueOf(v));
            t1.setText(String.valueOf(v));      
        }catch(NumberFormatException ne){
            try{
                t2.setText(cap);
            }catch(NumberFormatException e){
                t2.setText("BYE");
            }
        }
        switch(cap){
            case "+":
                pv=cv;                  
                break;
            case"=":                
                res=cv+pv;
                t1.setText(String.valueOf(res));
                break;      
        }           
    }
}

Answer 1

v=cv*10+Integer.parseInt(cap);中有一个例外，导致t2.setText(cap);被执行。

t1.setText（将String.valueOf（V））;与t2.setText（String.valueOf（v））不是交互式的;

1 个答案: