getActivity为空时如何终止线程

Question

Generally for terminating the Thread , the following code is used:

 new Thread((new Runnable() { @Override public void run() { ........ if (getActivity == null) return; } } ).start(); 

In this code, Checking the getActivity is done only for one time. Is there any code, so that whenever getActivity becomes null, return is called on the thread from where it is called.

Answer 1

You can catch the NullPointerException:

new Thread((new Runnable() {

      @Override
      public void run() {
          try {
              while (true) {
                  ...
                  // reference null Activity. Throw NPE
                  ...
              }
          } catch (NullPointerException e) {
              Log.e(DEBUG, "Activity reference became null. Finishing thread.");
          }

      }   
}  ).start();

Answer 2

You only must stop the Thread like:

 new Thread((new Runnable() {

          @Override
          public void run() {
              ........
              if (getActivity == null) return; //@tgkprog

          }   
 }  ).start();