CalledFromWrongThreadException

Question

 public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);
    final ThraedDemo objDemo = new ThraedDemo();
    Thread objThread = new Thread() {

        @Override
        public void run() {

            objDemo.firstMethod();
        }
    };
    objThread.start();
}


class ThraedDemo {

        private void firstMethod() {
            Thread objThread = new Thread() {

                @Override
                public void run() {
                    try {
                    ((ImageView)findViewById(R.id.ImageViewnumber)).setImageResource(nums[n]);

                        Thread.sleep(10000);
                        Log.v("Thread","1111111111111111sleep");
                    } catch (InterruptedException ex) {
                        System.out.println("interuped exception" + ex.getMessage());
                    }
                    secondMethod();
                }

                private void secondMethod() {
        Thread objThread = new Thread() {

            @Override
            public void run() {
                try {
                ((ImageView)findViewById(R.id.ImageViewResult)).setImageResource(nums[n+1]);

                n++;

                    Thread.sleep(10000);
                   Log.v("Thread","22222222222 sleep");
                } catch (InterruptedException ex) {
                    System.out.println("interuped exception" + ex.getMessage());
                }
                firstMethod();
            }
        };
        objThread.start();
    }

            };
            objThread.start();
        }

    }

I use the above code but it is not running.it got CalledFromWrongThreadException what is the problem inb the above code.Please give me some suggestions.Thanks in advance

Answer 1

I think you can't do view modifications from another thread than the UI thread, so either create handlers in the oncreate and post your thread to it, or use AsyncTask, or runOnUIThread method to send portions of code directly to the UI thread.