在關閉應用程序時：如何停止線程？

Question

我使用下面的代碼來使用UDP接收數據。當我點擊後退按鈕時，我的屏幕視覺被關閉，並顯示主屏幕。但是一個線程正在後臺工作（它從UDP服務器接收數據）。當我關閉應用程序時，我也需要停止線程。如何停止線程？

public void onClick(View view) { 
    port=Integer.parseInt(etd_port.getText().toString()); 
    etd_port.setCursorVisible(false); 
    Thread fst = new Thread(new Server()); 
    fst.start(); 
} 

public class Server implements Runnable { 
    private String tagid="",roomid=""; 
    public final int SERVERPORT = port; 
    private DatagramSocket ds; 
    private String recdata; 

    @Override 
    public void run() { 
     int buffer_size = 1024; 
     byte buffer[] = new byte[buffer_size]; 
     try { 
      ds = new DatagramSocket(SERVERPORT); 
      while (true) { 
       DatagramPacket p = new DatagramPacket(buffer, buffer.length); 
       ds.receive(p); 
       Log.d("MY UDP ","After Receive"); 
       recdata=new String(p.getData(),0,p.getLength()); 
       Log.d("Receive data ",recdata); 
      } 
     } catch(Exception e){ 
      Log.e("MY UDP ", " Error", e); 
     } 
    } 
} 
...... 

@Override 
protected void onStop() { 
    finish(); 
    fst.stop(); 
    super.onStop(); 
} 

Answer 1

你必須改變while條件：

class Server implements Runnable { 
    private boolean running; 

    public void run() { 
     running = true; 

     while (running) { 
      // do stuff here 
     } 
    } 
    public stop() { 
     running = false 
    } 
} 

protected void onStop() { 
    fst.stop() 
}