title: How to stop runnable when the app goes to background?
body: <p>I am trying to establish a runnable which can load ads by every 5 sec interval (of course 5 sec is too fast, it's just for testing purpose)</p>
  
  <p>Here is my code:</p>
  
  <pre><code>package com.admobsdk_dfp_handler;
  
  import com.google.ads.*;
  import com.google.ads.doubleclick.*;
  
  import android.os.Bundle;
  import android.os.Handler;
  import android.app.Activity;
  import android.view.Menu;
  import android.widget.RelativeLayout;
  
  public class AdMobSDK_DFP_Handler extends Activity {
      private DfpAdView adView;
      private Handler handler = new Handler();
      private Runnable runnable = new Runnable() {
  
          public void run() {
          adView.loadAd(new AdRequest());
          handler.postDelayed(this, 5000);
      }
      };
  
      @Override
      protected void onCreate(Bundle savedInstanceState) {
          super.onCreate(savedInstanceState);
          setContentView(R.layout.activity_ad_mob_sdk__dfp__handler);
  
          adView = new DfpAdView(
                  this,
                  AdSize.BANNER,
                  AD_UNIT_ID);
  
          RelativeLayout layout = (RelativeLayout) findViewById(R.id.mainLayout);
  
          layout.addView(adView);
  
          adView.loadAd(new AdRequest());
  
          handler.postDelayed(runnable, 5000);
  
  
      };
  
      @Override
      protected void onDestroy() {
          handler.removeCallbacks(runnable);
          super.onDestroy();
      }
  
  
      @Override
      public boolean onCreateOptionsMenu(Menu menu) {
          // Inflate the menu; this adds items to the action bar if it is present.
          getMenuInflater().inflate(R.menu.activity_ad_mob_sdk__dfp__handler,
                  menu);
          return true;
      }
  
  }
  </code></pre>
  
  <p>If I press home button to hide the app to the background, the runnable keeps loading ads by 5 sec interval.</p>
  
  <p>Is there any method to stop runnable when an app is hidden to the background? Many thanks.</p>