我無法修改我的布爾字段？

Question

那麼這個問題解釋它，不管我做什麼我不能修改我的布爾字段。下面的代碼是我正在做的任務中的一個類，但我需要能夠修改布爾值，以便做到這一點，我不能出於某種原因，所以我不知道發生了什麼事情：

使用

import java.awt.Color; 
    import java.awt.Component; 
    import java.awt.Font; 
    import java.awt.Graphics; 
    import java.awt.Graphics2D; 
    import java.awt.Shape; 
    import java.awt.event.ActionEvent; 
    import java.awt.event.ActionListener; 
    import java.awt.geom.Rectangle2D; 

    import javax.swing.JFrame; 
    import javax.swing.JLabel; 
    import javax.swing.JPanel; 
    import javax.swing.Timer; 
    @SuppressWarnings("serial") 

    public class Test extends JPanel implements ActionListener { 

    private String senderName,reciverName,message; 
    private int w=250,velx=13,x=330,senderW=350,senderH=100,reciverW=350,reciverH=270,messageW=350,messageH=50; 
    private Timer tm = new Timer(50, this); 
    private boolean something=true; 

    public void setSomething(boolean s){    
     something=s; 
    } 

    public Test(String s1,String s2, String s3){ 
      String cutString1 = s1.substring(0, Math.min(15, s1.length())); 
      String cutString2 = s2.substring(0, Math.min(15, s2.length())); 
      String cutString3 = s3.substring(0, Math.min(30, s3.length())); 

      senderName=cutString1; 
      reciverName=cutString2; 
      message=cutString3;     
      setSomething(false); 
      //Even though I set it to false it still holds true and won't print it out 
      if(something=false){     
       System.out.print("Something");     
      }     
      setLayout(null);     
      timer(); 
    } 

    public void timer(){    
     tm.setInitialDelay(10000); 
     tm.start();   
    } 

    public void paintComponent(Graphics g){ 
     setOpaque(true);    
     super.paintComponent(g); 
     Font font1 = new Font( "TimesRoman", Font.BOLD, 17); 
     Font font2 = new Font( "TimesRoman", Font.BOLD, 30);   
     g.setColor(Color.CYAN); 
     g.fillRect(330, 30, 250, 390); 
     g.setFont(font1); 
     g.setColor(Color.BLUE); 
     g.drawString(message, messageW, messageH); 
     g.setColor(Color.RED); 
     g.fillRect(x, 30, w, 390); 
     g.setColor(Color.BLUE); 
     g.setFont(font2); 
     g.drawString(senderName, senderW, senderH); 
     g.drawString("To",430, 200); 
     g.drawString(reciverName, reciverW, reciverH); 
     } 

    public void anime(){    
     w=w-velx; 
     repaint(); 
    } 

    public void actionPerformed(ActionEvent e){     
       anime(); 
    }  

    public static void main(String[] args){ 
     JFrame frame2 = new JFrame(); 
     frame2.add(new Test("something","something","something")); 
     frame2.setTitle("Title"); 
     frame2.setSize(700,500); 
     frame2.setResizable(true); 
     frame2.setLocationRelativeTo(null); 
     frame2.setVisible(true);    
    } 
} 

Answer 1

特殊照顧賦值檢查變量something這將永遠是false所以你print聲明將永遠不會達到：

if (something = false) { 

使用布爾檢查的縮寫形式避免了這種類型的錯誤：

if (!something) { 

Answer 2

An if statement consists of a Boolean expression followed by one or more statements.

更改此

if(something=false){ 

      System.out.print("Something"); 

     } 

與

if(!something){ // for false check } 

或

if(something) // for true check 

例爲什麼如果（布爾=布爾值）不是編譯時間錯誤

public static void main(String[] args) { 
    boolean test = true; 
    int a = 0; 
    boolean test1 = false; 
    test1 = (test = true); // no error boolean expression 
    test = (a = 1); // compile error not a boolean expression 
    if(test = false) 
    { 

    } 
    System.out.println("" + test); 
}