Android利用Theme自定义Activity间的切换动画

<?xml version="1.0" encoding="utf-8"?>
<alpha xmlns:android="http://schemas.android.com/apk/res/android"
 android:duration="300"
 android:fromAlpha="0.0"
 android:interpolator="@android:anim/accelerate_interpolator"
 android:toAlpha="1.0" />

<?xml version="1.0" encoding="utf-8"?>
<alpha xmlns:android="http://schemas.android.com/apk/res/android"
 android:duration="300"
 android:fromAlpha="1.0"
 android:interpolator="@android:anim/accelerate_interpolator"
 android:toAlpha="0.0" />

 <style name="Anim_fade" parent="android:Theme.NoTitleBar">
 <item name="android:windowAnimationStyle">@style/fade</item>
 </style>

 <style name="fade" parent="@android:style/Animation.Activity">
 <item name="android:activityOpenEnterAnimation">@anim/fade_in</item>
 <item name="android:activityOpenExitAnimation">@anim/fade_out</item>
 <item name="android:activityCloseEnterAnimation">@anim/fade_in</item>
 <item name="android:activityCloseExitAnimation">@anim/fade_out</item>
 </style>

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
 package="com.example.customanimationforactivity"
 android:versionCode="1"
 android:versionName="1.0" >

 <uses-sdk
 android:minSdkVersion="10"
 android:targetSdkVersion="10" />

 <application
 android:allowBackup="true"
 android:icon="@drawable/ic_launcher"
 android:label="@string/app_name"
 android:theme="@android:style/Theme.NoTitleBar" >
 <activity
  android:name="com.example.customanimationforactivity.MainActivity"
  android:label="@string/app_name"
  android:theme="@style/Anim_fade" >
  <intent-filter>
  <action android:name="android.intent.action.MAIN" />
  <category android:name="android.intent.category.LAUNCHER" />
  </intent-filter>
 </activity>
 <activity android:name=".AppActivity" android:theme="@style/Anim_fade" >
 </activity>
 </application>

</manifest>

package com.example.customanimationforactivity;

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

public class MainActivity extends Activity
{

 private Handler handler = new Handler();

 @Override
 protected void onCreate(Bundle savedInstanceState)
 {
 super.onCreate(savedInstanceState);
 setContentView(R.layout.activity_main);
 handler.postDelayed(new Runnable()
 {
 @Override
 public void run()
 {
 Intent intent = new Intent(MainActivity.this, AppActivity.class);
 startActivity(intent);
 finish();
 }
 }, 1000);

 }

}