android之绕Y轴旋转
转自:http://lzyfn123.iteye.com/blog/1426844
Android中并没有提供直接做3D翻转的动画,所以关于3D翻转的动画效果需要我们自己实现,那么我们首先来分析一下Animation 和 Transformation。
Animation动画的主要接口,其中主要定义了动画的一些属性比如开始时间,持续时间,是否重复播放等等。而 Transformation中则包含一个矩阵和alpha值,矩阵是用来做平移,旋转和缩放动画的,而alpha值是用来做alpha动画的,要实现 3D旋转动画我们需要继承自Animation类来实现,我们需要重载getTransformation和applyTransformation,在 getTransformation中Animation会根据动画的属性来产生一系列的差值点,然后将这些差值点传给 applyTransformation,这个函数将根据这些点来生成不同的Transformation。下面是具体实现:
- publicclassRotate3dAnimationextendsAnimation{
- //开始角度
- privatefinalfloatmFromDegrees;
- //结束角度
- privatefinalfloatmToDegrees;
- //中心点
- privatefinalfloatmCenterX;
- privatefinalfloatmCenterY;
- privatefinalfloatmDepthZ;
- //是否需要扭曲
- privatefinalbooleanmReverse;
- //摄像头
- privateCameramCamera;
- publicRotate3dAnimation(floatfromDegrees,floattoDegrees,
- floatcenterX,floatcenterY,floatdepthZ,booleanreverse){
- mFromDegrees=fromDegrees;
- mToDegrees=toDegrees;
- mCenterX=centerX;
- mCenterY=centerY;
- mDepthZ=depthZ;
- mReverse=reverse;
- }
- @Override
- publicvoidinitialize(intwidth,intheight,intparentWidth,intparentHeight){
- super.initialize(width,height,parentWidth,parentHeight);
- mCamera=newCamera();
- }
- //生成Transformation
- @Override
- protectedvoidapplyTransformation(floatinterpolatedTime,Transformationt){
- finalfloatfromDegrees=mFromDegrees;
- //生成中间角度
- floatdegrees=fromDegrees+((mToDegrees-fromDegrees)*interpolatedTime);
- finalfloatcenterX=mCenterX;
- finalfloatcenterY=mCenterY;
- finalCameracamera=mCamera;
- finalMatrixmatrix=t.getMatrix();
- camera.save();
- if(mReverse){
- camera.translate(0.0f,0.0f,mDepthZ*interpolatedTime);
- }else{
- camera.translate(0.0f,0.0f,mDepthZ*(1.0f-interpolatedTime));
- }
- camera.rotateY(degrees);
- //取得变换后的矩阵
- camera.getMatrix(matrix);
- camera.restore();
- matrix.preTranslate(-centerX,-centerY);
- matrix.postTranslate(centerX,centerY);
- }
- }
其中包括了旋转的开始和结束角度,中心点、是否扭曲、和一个Camera,这里我们主要分析applyTransformation函 数,其中第一个参数就是通过getTransformation函数传递的差指点,然后我们根据这个差值通过线性差值算法计算出一个中间角度 degrees,Camera类是用来实现绕Y轴旋转后透视投影的,因此我们首先通过t.getMatrix()取得当前的矩阵,然后通过 camera.translate来对矩阵进行平移变换操作,camera.rotateY进行旋转。这样我们就可以很轻松的实现3D旋转效果了,该例子 的原意是通过一个列表来供用户选择要实现翻转的图像,所以我们分析至少需要定义两个控件:ListView和ImageView(要翻转的图像),主界面 的xml布局定义如下所示。
- <FrameLayoutxmlns:android="http://schemas.android.com/apk/res/android"
- android:id="@+id/container"
- android:layout_width="match_parent"
- android:layout_height="match_parent">
- <ListView
- android:id="@android:id/list"
- android:persistentDrawingCache="animation|scrolling"
- android:layout_width="match_parent"
- android:layout_height="match_parent"
- android:layoutAnimation="@anim/layout_bottom_to_top_slide"/>
- <ImageView
- android:id="@+id/picture"
- android:scaleType="fitCenter"
- android:layout_width="match_parent"
- android:layout_height="match_parent"
- android:visibility="gone"/>
- </FrameLayout>
然后准备好需要的资源,在onCreate函数中准备好ListView和ImageView,因为要旋转所以我们需要保存视图的缓存 信息,通过setPersistentDrawingCache(ViewGroup.PERSISTENT_ANIMATION_CACHE);可以设 置该功能,当我们选择列表中的图像资源后在onItemClick中将选择的资源Id对应的图像设置到ImageView中,然后通过 applyRotation来启动一个动画,前面有了Rotate3dAnimation的实现,我们要完成3D翻转动画就很简单,直接构建一个 Rotate3dAnimation对象,设置其属性(包括动画监听),这里将动画的监听设置为DisplayNextView,可以用来显示下一个视 图,在其中的动画结束监听(onAnimationEnd)中,通过一个县城SwapViews来交换两个画面,交换过程则是设置ImageView和 ListView的显示相关属性,并构建一个Rotate3dAnimation对象,对另一个界面进行旋转即可,然后启动动画,整个转换过程实际上就是 将第一个界面从0度转好90度,然后就爱你过第二个界面从90度转到0度,这样就形成了一个翻转动画,完整代码如下,我们也加入了一些必要的注解,大家也 可以参考APIDemo中的Transition3d例子。
- publicclassTransition3dextendsActivityimplements
- AdapterView.OnItemClickListener,View.OnClickListener{
- //照片列表
- privateListViewmPhotosList;
- privateViewGroupmContainer;
- privateImageViewmImageView;
- //照片的名字,用于显示在list中
- privatestaticfinalString[]PHOTOS_NAMES=newString[]{
- "Lyon",
- "Livermore",
- "TahoePier",
- "LakeTahoe",
- "GrandCanyon",
- "Bodie"
- };
- //资源id
- privatestaticfinalint[]PHOTOS_RESOURCES=newint[]{
- R.drawable.photo1,
- R.drawable.photo2,
- R.drawable.photo3,
- R.drawable.photo4,
- R.drawable.photo5,
- R.drawable.photo6
- };
- @Override
- protectedvoidonCreate(BundlesavedInstanceState){
- super.onCreate(savedInstanceState);
- setContentView(R.layout.animations_main_screen);
- mPhotosList=(ListView)findViewById(android.R.id.list);
- mImageView=(ImageView)findViewById(R.id.picture);
- mContainer=(ViewGroup)findViewById(R.id.container);
- //准备ListView
- finalArrayAdapteradapter=newArrayAdapter(this,
- android.R.layout.simple_list_item_1,PHOTOS_NAMES);
- mPhotosList.setAdapter(adapter);
- mPhotosList.setOnItemClickListener(this);
- //准备ImageView
- mImageView.setClickable(true);
- mImageView.setFocusable(true);
- mImageView.setOnClickListener(this);
- //设置需要保存缓存
- mContainer.setPersistentDrawingCache(ViewGroup.PERSISTENT_ANIMATION_CACHE);
- }
- /**
- *Setupanew3Drotationonthecontainerview.
- *
- *@parampositiontheitemthatwasclickedtoshowapicture,or-1toshowthelist
- *@paramstartthestartangleatwhichtherotationmustbegin
- *@paramendtheendangleoftherotation
- */
- privatevoidapplyRotation(intposition,floatstart,floatend){
- //计算中心点
- finalfloatcenterX=mContainer.getWidth()/2.0f;
- finalfloatcenterY=mContainer.getHeight()/2.0f;
- //Createanew3Drotationwiththesuppliedparameter
- //Theanimationlistenerisusedtotriggerthenextanimation
- finalRotate3dAnimationrotation=
- newRotate3dAnimation(start,end,centerX,centerY,310.0f,true);
- rotation.setDuration(500);
- rotation.setFillAfter(true);
- rotation.setInterpolator(newAccelerateInterpolator());
- //设置监听
- rotation.setAnimationListener(newDisplayNextView(position));
- mContainer.startAnimation(rotation);
- }
- publicvoidonItemClick(AdapterViewparent,Viewv,intposition,longid){
- //设置ImageView
- mImageView.setImageResource(PHOTOS_RESOURCES[position]);
- applyRotation(position,0,90);
- }
- //点击图像时,返回listview
- publicvoidonClick(Viewv){
- applyRotation(-1,180,90);
- }
- /**
- *Thisclasslistensfortheendofthefirsthalfoftheanimation.
- *Itthenpostsanewactionthateffectivelyswapstheviewswhenthecontainer
- *isrotated90degreesandthusinvisible.
- */
- privatefinalclassDisplayNextViewimplementsAnimation.AnimationListener{
- privatefinalintmPosition;
- privateDisplayNextView(intposition){
- mPosition=position;
- }
- publicvoidonAnimationStart(Animationanimation){
- }
- //动画结束
- publicvoidonAnimationEnd(Animationanimation){
- mContainer.post(newSwapViews(mPosition));
- }
- publicvoidonAnimationRepeat(Animationanimation){
- }
- }
- /**
- *Thisclassisresponsibleforswappingtheviewsandstartthesecond
- *halfoftheanimation.
- */
- privatefinalclassSwapViewsimplementsRunnable{
- privatefinalintmPosition;
- publicSwapViews(intposition){
- mPosition=position;
- }
- publicvoidrun(){
- finalfloatcenterX=mContainer.getWidth()/2.0f;
- finalfloatcenterY=mContainer.getHeight()/2.0f;
- Rotate3dAnimationrotation;
- if(mPosition>-1){
- //显示ImageView
- mPhotosList.setVisibility(View.GONE);
- mImageView.setVisibility(View.VISIBLE);
- mImageView.requestFocus();
- rotation=newRotate3dAnimation(90,180,centerX,centerY,310.0f,false);
- }else{
- //返回listview
- mImageView.setVisibility(View.GONE);
- mPhotosList.setVisibility(View.VISIBLE);
- mPhotosList.requestFocus();
- rotation=newRotate3dAnimation(90,0,centerX,centerY,310.0f,false);
- }
- rotation.setDuration(500);
- rotation.setFillAfter(true);
- rotation.setInterpolator(newDecelerateInterpolator());
- //开始动画
- mContainer.startAnimation(rotation);
- }
- }
- }
更多相关文章
- android之ViewFlipper实现左右滑动动画效果
- android listview每个item定义动画呈现
- Android启动画面Splash
- Android创建逐帧动画的方式
- android 加载进度条动画
- android实现播放器反射性动画效果
- Android显示GIF动画完整示例(一)
- [Android] Android Tweened Animations动画使用详解二