Android 欢迎界面淡出动画效果(Animation)

 package com.example.testanimation;

    
  
    
 import android.app.Activity;
    
 import android.os.Bundle;
    
 import android.view.Menu;
    
 import android.view.MenuItem;
    
 import android.view.animation.AlphaAnimation;
    
 import android.widget.ImageView;
    
  
    
 public class MainActivity extends Activity {
    
     
    
 	
    
 	    private   ImageView   show;
    
 	
    
 	@Override
    
 	protected void onCreate(Bundle savedInstanceState) {
    
 		super.onCreate(savedInstanceState);
    
 		setContentView(R.layout.activity_main);
    
 		
    
 		show = (ImageView)findViewById(R.id.gradually);
    
 		  AlphaAnimation   alpha = new AlphaAnimation(1.0f, 0.0f);
    
 		  alpha.setDuration(4000);
    
 		  alpha.setFillAfter(true);
    
 		  show.setAnimation(alpha);
    
 	}
    
  
    
 	@Override
    
 	public boolean onCreateOptionsMenu(Menu menu) {
    
 		// Inflate the menu; this adds items to the action bar if it is present.
    
 		getMenuInflater().inflate(R.menu.main, menu);
    
 		return true;
    
 	}
    
  
    
 	@Override
    
 	public boolean onOptionsItemSelected(MenuItem item) {
    
 		// Handle action bar item clicks here. The action bar will
    
 		// automatically handle clicks on the Home/Up button, so long
    
 		// as you specify a parent activity in AndroidManifest.xml.
    
 		int id = item.getItemId();
    
 		if (id == R.id.action_settings) {
    
 			return true;
    
 		}
    
 		return super.onOptionsItemSelected(item);
    
 	}
    
 }

 <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"

    
     xmlns:tools="http://schemas.android.com/tools"
    
     android:layout_width="match_parent"
    
     android:layout_height="match_parent"
    
     >
    
     
    
     <TextView   
    
               android:layout_width="wrap_content"
    
               android:layout_height="wrap_content"
    
               android:text="你好"
    
              
    
             android:layout_centerInParent="true"
    
               android:textSize="30sp"></TextView>
    
  
    
     <ImageView
    
                  android:id="@+id/gradually"
    
                  android:layout_height="fill_parent"
    
                  android:layout_width="fill_parent" 
    
                  android:background="@drawable/senery"/>
    
  
    
 </RelativeLayout>