Textview animation error

Question

I'm trying to add an animation to a textview when my activity start. However, I get this error (10 seconds) after my activity starts. This is the log:

FATAL EXCEPTION: Thread-10028
Process: be.ugent.myapplication, PID: 14929
android.view.ViewRootImpl$CalledFromWrongThreadException: Only the original thread that created a view hierarchy can touch its views.
at android.view.ViewRootImpl.checkThread(ViewRootImpl.java:6462)
at android.view.ViewRootImpl.invalidateChildInParent(ViewRootImpl.java:932)
at android.view.ViewGroup.invalidateChild(ViewGroup.java:4693)
at android.view.View.invalidateInternal(View.java:11806)
at android.view.View.invalidate(View.java:11770)
at android.view.View.startAnimation(View.java:17877)
at be.ugent.myapplication.SplashScreen$1.run(SplashScreen.java:40)

and this is my SplashScreen.Java:

public class SplashScreen extends Activity {

    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.splash);
        final TextView wtext = (TextView)(findViewById(R.id.wtext));
        Thread mSplashThread;
        Animation animation = AnimationUtils.loadAnimation(this, R.anim.abc_fade_in);
        wtext.startAnimation(animation);

        // The thread to wait for 5 seconds
        mSplashThread =  new Thread() {
            @Override
            public void run(){
                try {
                    Thread.sleep(10000);
                }
                catch(InterruptedException ex){
                } finally{
                    //start animation for fadeout after 5 seconds
                    Animation animation1 = AnimationUtils.loadAnimation(getApplicationContext(), R.anim.abc_fade_out);
                    wtext.startAnimation(animation1);
                    //Start next activity
                    Intent intent = new Intent(SplashScreen.this,MainActivity.class);
                    startActivity(intent);
                }
            }
        };
        mSplashThread.start();
    }
}

Can someone take a look at it? Thanks! Kind regards!

Answer 1

You have to affect views only from UI thread. As a solution you can use handler created in UI thread.

protected void onCreate(Bundle savedInstanceState) {
    Handler handler = new Handler();
    super.onCreate(savedInstanceState);
    setContentView(R.layout.splash);
    final TextView wtext = (TextView)(findViewById(R.id.wtext));
    Thread mSplashThread;
    Animation animation = AnimationUtils.loadAnimation(this, R.anim.abc_fade_in);
    wtext.startAnimation(animation);


    Runnable task = new Runnable() {    
        public void run() {
            Animation animation1 = AnimationUtils.loadAnimation(getApplicationContext(), R.anim.abc_fade_out);
            wtext.startAnimation(animation1);
            //Start next activity
            Intent intent = new Intent(SplashScreen.this,MainActivity.class);
            startActivity(intent);
        }
    }
    handler.postDelayed(task, 10000);
    ...
}