2016-07-28 47 views
-11

我想打印,如:使用循環重複無限次的語句?

for(int i=0;i<should be infinite;i++) 
{ 
    Data is Loading. 
    sleep(100); 
    Data is Loading.. 
    sleep(100); 
    Data is Loading... 
    sleep(100); 
} 
下面

是它不工作

package com.queen.a01_simple_request; 

import android.os.Bundle; 
import android.support.v7.app.AppCompatActivity; 
import android.view.View; 
import android.widget.Button; 
import android.widget.TextView; 

public class MainActivity extends AppCompatActivity { 
TextView textView; 
Button button; 

@Override 
protected void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.activity_main); 

    textView = (TextView) findViewById(R.id.textView); 
    button = (Button) findViewById(R.id.button); 

    button.setOnClickListener(new View.OnClickListener() { 
     @Override 
     public void onClick(View view) { 
      for (; ;) { 
       try { 
        textView.setText("Downloading The File"); 
        Thread.sleep(1000); 
        textView.setText("Downloading The File."); 
        Thread.sleep(1000); 
        textView.setText("Downloading The File.."); 
        Thread.sleep(1000); 
        textView.setText("Downloading The File..."); 
        Thread.sleep(1000); 

       } catch (InterruptedException e) { 
        e.printStackTrace(); 
       } 
      } 
     } 
    }); 
} 

}

現在,這應該循環無限代碼。點應該永遠改變。我不想設置像我這樣的價值< 1000.我想實現這一點。

+4

如果你想要一個infinit循環然後只是做一個'while(true)' – mayha

+0

你能給我舉個例子嗎? –

+1

簡單地省略guard條件:'for(int i = 0;/* nothing * /; i ++)'。 –

回答

-1

試試這個:

while(true){ 
    code... 
} 
1

basic for statement的前3個 「零件」 都是可選:

for ([ForInit] ; [Expression] ; [ForUpdate]) Statement 

所以,雖然它看起來很奇怪,這是一個有效的循環(什麼都不做,永遠):

for (;;); 

在你的情況,只是省略Expression

for (int i = 0; ; i++) { ... } 
0
for(;;){ 
    { 
    try{ 
    Data is Loading. 
    Thread.sleep(100); 
    Data is Loading.. 
    Thread.sleep(100); 
    Data is Loading... 
    Thread.sleep(100); 
    }catch(Exception ignored){} 
    } 

編輯: 如果你在主線程上做這個(UI線程),它會響應的應用程序,你必須開始在這樣的背景下循環:

new Thread(new Runnable(){ 
    @Override 
    public void run(){ 
     for(;;){ 
      try{ 
      Data is Loading. 
      Thread.sleep(100); 
      Data is Loading.. 
      Thread.sleep(100); 
      Data is Loading... 
      Thread.sleep(100); 
      }catch(Exception ignored){} 
     } 
    } 
} 
+0

youzking,它不工作.. 當我按下按鈕,它就像凍結... –

+1

@AppleAppala很好啊。你請求了一個無限循環 –

+0

@TimCastelijns葉..我發佈上面的輸出...它不工作...請看看.. –