Android开发 之 viewGroup视图动画

视图组添加，移除，隐藏，显示动画

ViewGroup ，LinearLayout，FrameLayout ，RelativeLayout等都是视图组，在他们添加，删除，显示隐藏的子view的时候的动画效果

如果想使用系统默认的动画效果只需添加一个属性

<LinearLayout
    android:orientation="vertical"
    android:layout_width="wrap_content"
    android:layout_height="match_parent"
    android:id="@+id/verticalContainer"
    android:animateLayoutChanges="true" />

当然也可以自定义动画效果：

您可以使用LayoutTransition类在ViewGroup中对动画布局进行更改。 ViewGroup中的视图可以在您将视图添加到ViewGroup或将其从ViewGroup中删除时或当您使用VISIBLE，INVISIBLE或GONE调用View的setVisibility（）方法时，看到并消失的动画。 当您添加或删除视图时，ViewGroup中的剩余视图也可以动画进入新的位置。 您可以通过调用setAnimator（）并传递具有以下LayoutTransition常量之一的Animator对象来在LayoutTransition对象中定义以下动画：
 APPEARING - 指示在容器中出现的项目上运行的动画的标志。（添加view自身的动画）
 CHANGE_APPEARING - 指示由于容器中出现新项目而正在更改的项目上运行的动画的标志。（添加view时，其他view的移动动画）
 DISAPPEARING - 指示在从容器中消失的项目上运行的动画的标志。（移除view自身的动画）
 CHANGE_DISAPPEARING - 指示由于项目从容器中消失而正在更改的项目上运行的动画的标志。（移除view时，其他view的动画）

LayoutTransition transition=new  LayoutTransition();

transition.setAnimator(LayoutTransition.APPEARING,自定义的animator)；

viewgroup.setLayoutTransition(transition);

自定义动画：可以参考apidemo中的LayoutAnimations示例

 private void createCustomAnimations(LayoutTransition transition) {
        // Changing while Adding
        PropertyValuesHolder pvhLeft =
                PropertyValuesHolder.ofInt("left", 0, 1);
        PropertyValuesHolder pvhTop =
                PropertyValuesHolder.ofInt("top", 0, 1);
        PropertyValuesHolder pvhRight =
                PropertyValuesHolder.ofInt("right", 0, 1);
        PropertyValuesHolder pvhBottom =
                PropertyValuesHolder.ofInt("bottom", 0, 1);
        PropertyValuesHolder pvhScaleX =
                PropertyValuesHolder.ofFloat("scaleX", 1f, 0f, 1f);
        PropertyValuesHolder pvhScaleY =
                PropertyValuesHolder.ofFloat("scaleY", 1f, 0f, 1f);
        customChangingAppearingAnim = ObjectAnimator.ofPropertyValuesHolder(
                        this, pvhLeft, pvhTop, pvhRight, pvhBottom, pvhScaleX, pvhScaleY).
                setDuration(transition.getDuration(LayoutTransition.CHANGE_APPEARING));
        customChangingAppearingAnim.addListener(new AnimatorListenerAdapter() {
            public void onAnimationEnd(Animator anim) {
                View view = (View) ((ObjectAnimator) anim).getTarget();
                view.setScaleX(1f);
                view.setScaleY(1f);
            }
        });


        // Changing while Removing
        Keyframe kf0 = Keyframe.ofFloat(0f, 0f);
        Keyframe kf1 = Keyframe.ofFloat(.9999f, 360f);
        Keyframe kf2 = Keyframe.ofFloat(1f, 0f);
        PropertyValuesHolder pvhRotation =
                PropertyValuesHolder.ofKeyframe("rotation", kf0, kf1, kf2);
        customChangingDisappearingAnim = ObjectAnimator.ofPropertyValuesHolder(
                        this, pvhLeft, pvhTop, pvhRight, pvhBottom, pvhRotation).
                setDuration(transition.getDuration(LayoutTransition.CHANGE_DISAPPEARING));
        customChangingDisappearingAnim.addListener(new AnimatorListenerAdapter() {
            public void onAnimationEnd(Animator anim) {
                View view = (View) ((ObjectAnimator) anim).getTarget();
                view.setRotation(0f);
            }
        });

        // Adding  以y走旋转出现
        customAppearingAnim = ObjectAnimator.ofFloat(null, "rotationY", 90f, 0f).
                setDuration(transition.getDuration(LayoutTransition.APPEARING));
        customAppearingAnim.addListener(new AnimatorListenerAdapter() {
            public void onAnimationEnd(Animator anim) {
                View view = (View) ((ObjectAnimator) anim).getTarget();
                view.setRotationY(0f);
            }
        });

        // Removing
        customDisappearingAnim = ObjectAnimator.ofFloat(null, "rotationX", 0f, 90f).
                setDuration(transition.getDuration(LayoutTransition.DISAPPEARING));
        customDisappearingAnim.addListener(new AnimatorListenerAdapter() {
            public void onAnimationEnd(Animator anim) {
                View view = (View) ((ObjectAnimator) anim).getTarget();
                view.setRotationX(0f);
            }
        });
    }