如何将用户变量传递给paint方法

Question

我是新手，所以下面的代码可能会有很多问题 它应该从文本字段中获取用户书面文本并为其绘制摩尔斯电码。它获取文本，将CharArray形式的String传输给此类，但paint方法不绘制任何内容（在paint方法中无法识别变量!!）。

输入：构造函数获取另一个类的链接（或其中的内容），字符串中的char以及字符串中的位置编号 输出：只绘制最后3行，不识别外部绘制方法的其他变量！

以下是不起作用的课程：

public class Procesare extends Canvas{
    Morse fereastra;
    String lit="",cod="";
    char car;
    int nr;

    public Procesare(Morse parinte,char c,int i){
        fereastra=parinte;
        car=c;  // with or without "this" doesn't seem to transmit values to the class
        nr=i;
        //this.lit=String.valueOf(c);
        switch (c){
                //this part is just testing that values were transmited, it works
                case 'a':
                    fereastra.canv.setBackground(Color.orange);
                    System.out.println(c+" .-");

                    break;
                case 'b': 
                    fereastra.canv.setBackground(Color.blue);
                    System.out.println(c+" -...");

                    break;
                case 'c': 
                    fereastra.canv.setBackground(Color.red);
                    System.out.println(c+" -.-.");

                    break;
                case 'd': 
                    fereastra.canv.setBackground(Color.green); 
                    System.out.println(c+" -..");

                    break;
                default: break;
            }
    }

    public void paint(Graphics g){
        lit=String.valueOf(car);
        switch (lit){
                case "a": cod=".-"; break;
                case "b": cod="-..."; break;

                default: break;
            }
        g.drawString(lit,5,10+nr*10);
        g.drawString(cod,15,10+nr*10);
        g.drawString(lit,5,10);  // these aren't drawing anything !?!?

        g.fillOval(15, 3, 6, 6); // just testing
        g.drawString("z",5,20);
        g.fillOval(15, 13, 6, 6); 
    }
}

主要类，有效：

public class Morse extends Frame {
    xText camp;
    Procesare proc,canv;
    String s1, str;
    char[] cuv;
    int n;

    public Morse(String titlu){
      super(titlu);
      init();
    }  
    public static void main (String args[]){
        Morse app=new Morse("Morse much?");
        app.setSize(250,250);
        app.show();
    }
    public boolean handleEvent(Event evt)  {
      if (evt.id==Event.WINDOW_DESTROY)
      {System.exit(0);}
      return super.handleEvent(evt);
    }

    public void init(){
        setLayout(new GridLayout(3,1,10,20));
        setBackground(Color.gray);
        canv=new Procesare(this,' ',0);
        canv.setBackground(Color.orange);
        camp=new xText(this,"Introduceti textul aici:");              
        add(camp);
        add(canv);

    }
    public Insets getInsets(){
        return new Insets(30,30,30,30);
    }
    void update(xText input){

        s1=input.cText1.getText();
        cuv = s1.toCharArray();

        for(n=0;n<s1.length();n++){
            proc=new Procesare(this,cuv[n],n);
        }

    }
}