本文是对API中的方法做了介绍，如果想要看如何让这些方法兼容4.x或2.x可以看这篇文章：

新版的V4包中有了这个类—— ActivityOptionsCompat，我们可以通过这个类来启动activity和添加动画。但不幸的是所有的动画都没有给2.x用的，大部分动画也对4.x不兼容。我们就来看看是否让低版本也兼容这些动画效果。

好消息是这个类是兼容2.x的，通过这个类编写的嗲吗，虽然不能给2.x带来动画，但也能确保全版本稳定运行，不会需要我们判断版本。也就是说如果你给5.x平台做了动画，其他平台虽然不会执行动画，但仍旧可以稳定打开activity。下面我们通过远吗进行分析下这个类。

1.文档解释

（1）ActivityOptionsCompat.makeCustomAnimation(context, enterResId, exitResId)

简单做一个定制的动画，这个参数很简单，传入一个进入的动画的id，和移除动画的id即可

//让新的Activity从一个小的范围扩大到全屏        ActivityOptionsCompat options =                 ActivityOptionsCompat.makeCustomAnimation(this,                         R.anim.slide_bottom_in, R.anim.slide_bottom_out);        startNewAcitivity(options);

private void startNewAcitivity(ActivityOptionsCompat options) {        Intent intent = new Intent(this,DetailActivity.class);          ActivityCompat.startActivity(this, intent, options.toBundle());      }

这个我感觉没什么用处，类似于

Intent intent = new Intent(this,DetailActivity.class);          startActivity(intent);        overridePendingTransition(R.anim.slide_bottom_in, android.R.anim.fade_out);

还不如直接用这个全版本的overridePendingTransition呢

 

（2）ActivityOptionsCompat.makeScaleUpAnimation(source, startX, startY, startWidth, startHeight)

这个在4.x上有用，可以实现新的Activity从某个固定的坐标以某个大小扩大至全屏，我觉得效果挺不错的。

这个新Activity就是从根据那个图片的坐标来拉伸展示的，对于相册是很好的展示效果。

private void scaleUpAnimation(View view) {        //让新的Activity从一个小的范围扩大到全屏        ActivityOptionsCompat options =                 ActivityOptionsCompat.makeScaleUpAnimation(view, //The View that the new activity is animating from                        (int)view.getWidth()/2, (int)view.getHeight()/2, //拉伸开始的坐标                        0, 0);//拉伸开始的区域大小，这里用（0，0）表示从无到全屏        startNewAcitivity(options);    }

private void startNewAcitivity(ActivityOptionsCompat options) {        Intent intent = new Intent(this,DetailActivity.class);          ActivityCompat.startActivity(this, intent, options.toBundle());      }

 

（3）ActivityOptionsCompat.makeSceneTransitionAnimation(activity, sharedElement, sharedElementName)

当你需要当前界面中的某个元素和新界面中的元素有关时，你可以使用这个动画。效果很赞~！

这个图片就是通过动画和上一个界面的图片进行了联系。

要使用这个方法就必须给两个不同Activity的中的布局元素设定同样的一个android:transitionName，然后还需要一个标志来告诉Window执行动画，因为这个只是在5.x上有效，不是本文的讨论范围。详细看官方文档即可。

标志：etWindow().requestFeature(Window.FEATURE_CONTENT_TRANSITIONS);

也可以参考文章：

http://blog.csdn.net/a396901990/article/details/40187203

http://blog.jobbole.com/77015/

 

（4）ActivityOptionsCompat.makeSceneTransitionAnimation((Activity arg0, Pair<View, String>...  arg1)

这个方法用于多个元素和新的Activity相关的情况，注意下第二个参数Pair这个键值对后面有...，标明是可以传入多个Pair对象的。

 

（5）ActivityOptionsCompat.makeThumbnailScaleUpAnimation(source, thumbnail, startX, startY)

这个方法可以用于4.x上，是将一个小块的Bitmpat进行拉伸的动画。

详细使用方式，参考官方文档：

 

2.源码

看完了文档，心里各种凄凉。很多优秀的动画都不向下兼容，那么我们去源码中看看我们的主流4.x版本能用上什么。

public class ActivityOptionsCompat {    /**     * Create an ActivityOptions specifying a custom animation to run when the     * activity is displayed.     *     * @param context Who is defining this. This is the application that the     * animation resources will be loaded from.     * @param enterResId A resource ID of the animation resource to use for the     * incoming activity. Use 0 for no animation.     * @param exitResId A resource ID of the animation resource to use for the     * outgoing activity. Use 0 for no animation.     * @return Returns a new ActivityOptions object that you can use to supply     * these options as the options Bundle when starting an activity.     */    public static ActivityOptionsCompat makeCustomAnimation(Context context,            int enterResId, int exitResId) {        if (Build.VERSION.SDK_INT >= 16) {            return new ActivityOptionsImplJB(                ActivityOptionsCompatJB.makeCustomAnimation(context, enterResId, exitResId));        }        return new ActivityOptionsCompat();    }    /**     * Create an ActivityOptions specifying an animation where the new activity is     * scaled from a small originating area of the screen to its final full     * representation.     * 
     * If the Intent this is being used with has not set its     * {
    @link android.content.Intent#setSourceBounds(android.graphics.Rect)},     * those bounds will be filled in for you based on the initial bounds passed     * in here.     *     * @param source The View that the new activity is animating from. This     * defines the coordinate space for startX and startY.     * @param startX The x starting location of the new activity, relative to     * source.     * @param startY The y starting location of the activity, relative to source.     * @param startWidth The initial width of the new activity.     * @param startHeight The initial height of the new activity.     * @return Returns a new ActivityOptions object that you can use to supply     * these options as the options Bundle when starting an activity.     */    public static ActivityOptionsCompat makeScaleUpAnimation(View source,            int startX, int startY, int startWidth, int startHeight) {        if (Build.VERSION.SDK_INT >= 16) {            return new ActivityOptionsImplJB(                ActivityOptionsCompatJB.makeScaleUpAnimation(source, startX, startY,                        startWidth, startHeight));        }        return new ActivityOptionsCompat();    }    /**     * Create an ActivityOptions specifying an animation where a thumbnail is     * scaled from a given position to the new activity window that is being     * started.     * 
     * If the Intent this is being used with has not set its     * {
    @link android.content.Intent#setSourceBounds(android.graphics.Rect)},     * those bounds will be filled in for you based on the initial thumbnail     * location and size provided here.     *     * @param source The View that this thumbnail is animating from. This     * defines the coordinate space for startX and startY.     * @param thumbnail The bitmap that will be shown as the initial thumbnail     * of the animation.     * @param startX The x starting location of the bitmap, relative to source.     * @param startY The y starting location of the bitmap, relative to source.     * @return Returns a new ActivityOptions object that you can use to supply     * these options as the options Bundle when starting an activity.     */    public static ActivityOptionsCompat makeThumbnailScaleUpAnimation(View source,            Bitmap thumbnail, int startX, int startY) {        if (Build.VERSION.SDK_INT >= 16) {            return new ActivityOptionsImplJB(                ActivityOptionsCompatJB.makeThumbnailScaleUpAnimation(source, thumbnail,                        startX, startY));        }        return new ActivityOptionsCompat();    }

 

/* * Copyright (C) 2012 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * *      http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */package android.support.v4.app;import android.app.ActivityOptions;import android.content.Context;import android.graphics.Bitmap;import android.os.Bundle;import android.view.View;class ActivityOptionsCompatJB {    public static ActivityOptionsCompatJB makeCustomAnimation(Context context,            int enterResId, int exitResId) {        return new ActivityOptionsCompatJB(            ActivityOptions.makeCustomAnimation(context, enterResId, exitResId));    }    public static ActivityOptionsCompatJB makeScaleUpAnimation(View source,            int startX, int startY, int startWidth, int startHeight) {        return new ActivityOptionsCompatJB(            ActivityOptions.makeScaleUpAnimation(source, startX, startY, startWidth, startHeight));    }    public static ActivityOptionsCompatJB makeThumbnailScaleUpAnimation(View source,            Bitmap thumbnail, int startX, int startY) {        return new ActivityOptionsCompatJB(            ActivityOptions.makeThumbnailScaleUpAnimation(source, thumbnail, startX, startY));    }    private final ActivityOptions mActivityOptions;    private ActivityOptionsCompatJB(ActivityOptions activityOptions) {        mActivityOptions = activityOptions;    }    public Bundle toBundle() {        return mActivityOptions.toBundle();    }    public void update(ActivityOptionsCompatJB otherOptions) {        mActivityOptions.update(otherOptions.mActivityOptions);    }}

 

我们可以完全了解到，4.x上能用的就这么三个动画效果，第一个第三我个人认为没啥用处，第二个效果好点，但仅仅适用于照片墙。于是就很悲剧了，这个新的类仅仅带来了低版本兼容不报错的效果，对于新的特性各种不支持。反过来想，反正动画这个东西对用户来说好看和不好看也没差，功能是最主要的。

这个是讲5.0动画效果的文章，如果做5.0开发的话可以看看。但我估计在4.x主流的今天，这些特效还只能自己写兼容包了。

 

动画

好了，虽然我们不能用这么酷炫的动画，但我们还可以用传统动画嘛。我研究了下图片放大的效果，写了一篇文章，其实还可以继续优化。贴上文章地址和效果图。

地址：

效果图：

 

下面分享下使用动画的方法，在启动activity的时候进行设置，然后在开启的activity中的onBackPressed()也进行相应的设置，就能出现流畅的效果啦。

举例：

MainActivity

private void simpleStartActivity() {        Intent intent = new Intent(this,DetailActivity.class);          startActivity(intent);        //overridePendingTransition(R.anim.slide_left_in, R.anim.slide_right_out);        overridePendingTransition(R.anim.slide_bottom_in, android.R.anim.fade_out);    }

 

DetailActivity

package com.kale.activityoptionstest;import android.os.Bundle;import android.support.v7.app.ActionBarActivity;public class DetailActivity extends ActionBarActivity{    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.item_detail);                    }    @Override    public void onBackPressed() {        super.onBackPressed();        //overridePendingTransition(R.anim.slide_right_in, R.anim.slide_left_out);        overridePendingTransition(0, R.anim.slide_bottom_out);    }    }

 

这样就可以实现，第二个Activity从屏幕下方出现，按下返回键后会从屏幕下方离开了。

 

最后给出几个常用的动画效果

slide_bottom_in.xml

 

slide_bottom_out.xml

 

slide_left_in.xml

 

slide_left_out.xml

 

slide_right_in.xml

 

slide_right_out.xml

 

slide_top_in.xml

 

slide_top_out.xml