如何在Java中仅一秒钟更改文本框的背景颜色？

Question

I want to change the color of my textbox to yellow for just a second, but I cant figure out how to. This is my code right now, what it is doing is that it just waits a second and give the textbox the second color.

 for(int i=0;i<2;i++){   
   if(i==0)
   {
textbox1.setBackground(Color.yellow); //Turn textbox yellow (first color)

try {
TimeUnit.SECONDS.sleep(1); //wait 1 second
} 
catch (InterruptedException e) {}
}       
else if(i==1)
   {
   textbox1.setBackground(Color.white); //Turn textbox white (second color)
   }       
}

Ps. I've also tried Thread.sleep(1000); insted of TimeUnit.SECONDS.sleep(1);

Answer 1

With your current code, you're putting your entire GUI to sleep, meaning it is frozen and will not show color changes or interact with the user. You should never call Thread.sleep(...) or similar code on the Swing event thread for this very reason.

Use a Swing Timer instead since this was built just for this type of purpose, to provide for time delayed Swing code, either once, or repeatedly.

eg,

textbox1.setBackground(Color.yellow);
int delayTime = 3 * 1000; // 3 seconds
new Timer(delayTime, new ActionListener() {
  public void actionPerformed(ActionEvent e) {
     textbox1.setBackground(Color.white);
     // stop the timer
     ((Timer) e.getSource()).stop();
  }
}).start();