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Question

Hello I would like to display an other splashscreen after the default one, if the App starts for the first time(right after installation eg)

So I wrote this. But the new Activity does not start it stays at the Splash screen. Can somebody say whats wrong with it?

import android.app.Activity;
import android.content.Intent;
import android.content.SharedPreferences;
import android.os.Bundle;
import android.preference.PreferenceManager;
import android.widget.TextView;

    public class splash extends Activity {
         private Thread splashTread;

        @Override
        protected void onCreate(Bundle savedInstanceState) {
            // TODO Auto-generated method stub
            super.onCreate(savedInstanceState);
            setContentView(R.layout.splash);

            SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(this);
            if(!prefs.getBoolean("firstTime", false)) {
                // run your one time code
                 Intent i = new Intent(splash.this, main.class);

                         startActivity(i);
                SharedPreferences.Editor editor = prefs.edit();
                editor.putBoolean("firstTime", true);
                editor.commit();


             // thread for displaying the SplashScreen
             splashTread = new Thread() {
                 @Override
                 public void run() {
                     try {
                         synchronized(this){

                                 //wait 2 sec
                                 wait(2000);
                         }

                     } catch(InterruptedException e) {}
                     finally {
                         finish();



                         //start a new activity
                         Intent i = new Intent();
                         i.setClass(splash.this, main.class);
                                 startActivity(i);

                         stop();
                     }
                 }
             };

             splashTread.start();

        }

    }
    }

Thanks.

Answer 1

From what I've seen, your code runs the same Activity (main) regardless of whether the launch is the first time or not. I'm assuming your purpose is to immediately launch the alternate splash screen if it's the first launch, otherwise to proceed to the main Activity after 2 seconds. Also, I would recommend using a Handler rather than a Thread, since you're only making use of it once, and on a delay. Try this:

    public class splash extends Activity
{
    private Handler handler = new Handler()
    {
        public void handleMessage(Message msg)
        {
            Intent i = new Intent(splash.this, main.class);
            splash.this.startActivity(i);
                                 this.finish()
        }
    };

    protected void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);

        SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(this);
        if(!prefs.getBoolean("first_time", false))
        {
            SharedPreferences.Editor editor = prefs.edit();
            editor.putBoolean("first_time", true);
            editor.commit();
            Intent i = new Intent(splash.this, otherSplash.class);
            this.startActivity(i);
                                 this.finish();
        }
        else
        {
            this.setContentView(R.layout.splash);
            handler.sendEmptyMessageDelayed(0, 2000);
        }

    }
}

Answer 2

Instead of calling finish() ... just start the main activity with FLAG_ACTIVITY_CLEAR_TOP

http://developer.android.com/reference/android/content/Intent.html#FLAG_ACTIVITY_CLEAR_TOP

Here's more information on that FLAG

FLAG_ACTIVITY_CLEAR_TOP in Android

To be clearer, what I'm suggesting is that you either

1. Make the Splash the default activity and in there call the Main activity after a timeout, OR, if the splash has already been seen (preference check). (ie, all splash logic is in the Splash activity)
2. Have the Main activity check to see if Splash should be called (preference check) and if so start it using the same CLEAR_TOP flag and then have the Splash timeout and set the Main again using the CLEAR_TOP after a couple of seconds. (This mixes the splash logic in both the Splash and the Main )

The end result is that Main will be the only activity on the stack, once the Splash is done.

Answer 3

If your intention is to simply have multiple "Splash" screens, and they have no logic to them, other than just displaying content, then why not just use a single activity and replace the view with a new view for the second splash. You'd have to do this update on the UI thread as well, so you'd need to either use the an Handler or use and AsyncTask , or use View.post() from a known view element in the current view.

Answer 4

I don't think you can/should start activity from a thread that is not the UI thread. Change to an AsyncTask, or use a Handler