How to set delay in android?

Question

Try this code:

import android.os.Handler;
...
final Handler handler = new Handler();
handler.postDelayed(new Runnable() {
    @Override
    public void run() {
        // Do something after 5s = 5000ms
        buttons[inew][jnew].setBackgroundColor(Color.BLACK);
    }
}, 5000);

You can use CountDownTimer which is much more efficient than any other solution posted. You can also produce regular notifications on intervals along the way using its onTick(long) method

Have a look at this example showing a 30seconds countdown

   new CountDownTimer(30000, 1000) {
         public void onFinish() {
             // When timer is finished 
             // Execute your code here
     }

     public void onTick(long millisUntilFinished) {
              // millisUntilFinished    The amount of time until finished.
     }
   }.start();

If you use delay frequently in your app, use this utility class

import android.os.Handler;


public class Utils {

    // Delay mechanism

    public interface DelayCallback{
        void afterDelay();
    }

    public static void delay(int secs, final DelayCallback delayCallback){
        Handler handler = new Handler();
        handler.postDelayed(new Runnable() {
            @Override
            public void run() {
                delayCallback.afterDelay();
            }
        }, secs * 1000); // afterDelay will be executed after (secs*1000) milliseconds.
    }
}

Usage:

// Call this method directly from java file

int secs = 2; // Delay in seconds

Utils.delay(secs, new Utils.DelayCallback() {
    @Override
    public void afterDelay() {
        // Do something after delay

    }
});

Using the Thread.sleep(millis) method.

If you want to do something in the UI on regular time intervals very good option is to use CountDownTimer:

new CountDownTimer(30000, 1000) {

     public void onTick(long millisUntilFinished) {
         mTextField.setText("seconds remaining: " + millisUntilFinished / 1000);
     }

     public void onFinish() {
         mTextField.setText("done!");
     }
  }.start();

Handler answer in Kotlin :

1 - Create a top-level function inside a file (for example a file that contains all your top-level functions) :

fun delayFunction(function: ()-> Unit, delay: Long) {
    Handler().postDelayed(function, delay)
}

2 - Then call it anywhere you needed it :

delayFunction({ myDelayedFunction() }, 300)