android create splash screen

activity_main.xml：

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >

    <TextView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="main page" />

</LinearLayout>

activity_splash.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >

    <ImageView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:src="@drawable/ic_launcher" />

</LinearLayout>

AndroidManifest.xml:

<activity
            android:name=".SplashActivity"
            android:label="splash" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
        <activity
            android:name=".MainActivity"
            android:label="@string/app_name" >
        </activity>

SplashActivity

package com.example.splashtest;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.os.Handler;
import android.view.Window;

public class SplashActivity extends Activity {

    private final int SPLASH_DISPLAY_LENGHT = 3000;
    private Handler handler;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        getWindow().requestFeature(Window.FEATURE_NO_TITLE);
        setContentView(R.layout.activity_splash);

        handler = new Handler();
        // Delay 3 seconds and then go to MainActivity
        handler.postDelayed(new Runnable() {

            @Override
            public void run() {
                Intent intent = new Intent(SplashActivity.this,
                        MainActivity.class);
                startActivity(intent);
                SplashActivity.this.finish();
            }
        }, SPLASH_DISPLAY_LENGHT);

    }
}

// disable back key
@Override    
public boolean onKeyDown(int keyCode, KeyEvent event) {  
　　if(keyCode == KeyEvent.KEYCODE_BACK){      
　　　　return  true;
　　}  
　　return  super.onKeyDown(keyCode, event);     

}

MainActivity:

package com.example.splashtest;

import android.app.Activity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;

public class MainActivity extends Activity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    }
}