android3D动画,绕y轴旋转

原文地址:http://blog.csdn.net/x_i_a_o_h_a_i/article/details/40449847

其实网上的3D旋转的例子很多，在这里我只是想把其代码做一个解释。

先上图：

代码：

TurnAroundActivity

/**
 * 图片浏览器的主Activity。
 *
 * @author guolin
 */
public class TurnAroundActivity extends Activity {
 
	/**
	 * 根布局
	 */
	private RelativeLayout layout;
 
	/**
	 * 用于展示图片列表的ListView
	 */
	private ListView picListView;
 
	/**
	 * 翻转后的布局
	 */
	private LinearLayout picture;
 
	/**
	 * 图片列表的适配器
	 */
	private PictureAdapter adapter;
 
	/**
	 * 存放所有图片的集合
	 */
	private List<Picture> picList = new ArrayList<Picture>();
 
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		requestWindowFeature(Window.FEATURE_NO_TITLE);
		setContentView(R.layout.activity_around);
		// 对图片列表数据进行初始化操作
		initPics();
		layout = (RelativeLayout) findViewById(R.id.layout);
		picListView = (ListView) findViewById(R.id.pic_list_view);
		picture = (LinearLayout) findViewById(R.id.picture);
		adapter = new PictureAdapter(this, 0, picList);
		picListView.setAdapter(adapter);
		picListView.setOnItemClickListener(new OnItemClickListener() {
			@Override
			public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
 
				// 获取布局的中心点位置，作为旋转的中心点
				float centerX = layout.getWidth() / 2f;
				float centerY = layout.getHeight() / 2f;
				// 构建3D旋转动画对象，旋转角度为0到90度，这使得ListView将会从可见变为不可见
				final Rotate3dAnimation rotation = new Rotate3dAnimation(0, 90, centerX, centerY,
						310.0f, true);
				// 动画持续时间500毫秒
				rotation.setDuration(500);
				// 动画完成后保持完成的状态
				rotation.setFillAfter(true);
				rotation.setInterpolator(new AccelerateInterpolator());
				// 设置动画的监听器
				rotation.setAnimationListener(new TurnToImageView());
				layout.startAnimation(rotation);
			}
		});
		picture.setOnClickListener(new OnClickListener() {
			@Override
			public void onClick(View v) {
				// 获取布局的中心点位置，作为旋转的中心点
				float centerX = layout.getWidth() / 2f;
				float centerY = layout.getHeight() / 2f;
				// 构建3D旋转动画对象，旋转角度为360到270度，这使得ImageView将会从可见变为不可见，并且旋转的方向是相反的
				final Rotate3dAnimation rotation = new Rotate3dAnimation(360, 270, centerX,
						centerY, 310.0f, true);
				// 动画持续时间500毫秒
				rotation.setDuration(500);
				// 动画完成后保持完成的状态
				rotation.setFillAfter(true);
				rotation.setInterpolator(new AccelerateInterpolator());
				// 设置动画的监听器
				rotation.setAnimationListener(new TurnToListView());
				layout.startAnimation(rotation);
			}
		});
	}
 
	/**
	 * 初始化图片列表数据。
	 */
	private void initPics() {
		Picture bird = new Picture("Bird", R.drawable.bird);
		picList.add(bird);
		Picture winter = new Picture("Winter", R.drawable.winter);
		picList.add(winter);
		Picture autumn = new Picture("Autumn", R.drawable.autumn);
		picList.add(autumn);
		Picture greatWall = new Picture("Great Wall", R.drawable.great_wall);
		picList.add(greatWall);
		Picture waterFall = new Picture("Water Fall", R.drawable.water_fall);
		picList.add(waterFall);
	}
 
	/**
	 * 注册在ListView点击动画中的动画监听器，用于完成ListView的后续动画。
	 *
	 * @author guolin
	 */
	class TurnToImageView implements AnimationListener {
 
		@Override
		public void onAnimationStart(Animation animation) {
		}
 
		/**
		 * 当ListView的动画完成后，还需要再启动ImageView的动画，让ImageView从不可见变为可见
		 */
		@Override
		public void onAnimationEnd(Animation animation) {
			// 获取布局的中心点位置，作为旋转的中心点
			float centerX = layout.getWidth() / 2f;
			float centerY = layout.getHeight() / 2f;
			// 将ListView隐藏
			picListView.setVisibility(View.GONE);
			// 将ImageView显示
			picture.setVisibility(View.VISIBLE);
			picture.requestFocus();
			// 构建3D旋转动画对象，旋转角度为270到360度，这使得ImageView将会从不可见变为可见
			final Rotate3dAnimation rotation = new Rotate3dAnimation(270, 360, centerX, centerY,
					310.0f, false);
			// 动画持续时间500毫秒
			rotation.setDuration(500);
			// 动画完成后保持完成的状态
			rotation.setFillAfter(true);
			rotation.setInterpolator(new AccelerateInterpolator());
			layout.startAnimation(rotation);
		}
 
		@Override
		public void onAnimationRepeat(Animation animation) {
		}
 
	}
 
	/**
	 * 注册在ImageView点击动画中的动画监听器，用于完成ImageView的后续动画。
	 *
	 * @author guolin
	 */
	class TurnToListView implements AnimationListener {
 
		@Override
		public void onAnimationStart(Animation animation) {
		}
 
		/**
		 * 当ImageView的动画完成后，还需要再启动ListView的动画，让ListView从不可见变为可见
		 */
		@Override
		public void onAnimationEnd(Animation animation) {
			// 获取布局的中心点位置，作为旋转的中心点
			float centerX = layout.getWidth() / 2f;
			float centerY = layout.getHeight() / 2f;
			// 将ImageView隐藏
			picture.setVisibility(View.GONE);
			// 将ListView显示
			picListView.setVisibility(View.VISIBLE);
			picListView.requestFocus();
			// 构建3D旋转动画对象，旋转角度为90到0度，这使得ListView将会从不可见变为可见，从而回到原点
			final Rotate3dAnimation rotation = new Rotate3dAnimation(90, 0, centerX, centerY,
					310.0f, false);
			// 动画持续时间500毫秒
			rotation.setDuration(500);
			// 动画完成后保持完成的状态
			rotation.setFillAfter(true);
			rotation.setInterpolator(new AccelerateInterpolator());
			layout.startAnimation(rotation);
		}
 
		@Override
		public void onAnimationRepeat(Animation animation) {
		}
 
	}
 
}

关键类：

Rotate3dAnimation

/**
 * An animation that rotates the view on the Y axis between two specified
 * angles. This animation also adds a translation on the Z axis (depth) to
 * improve the effect.
 */
public class Rotate3dAnimation extends Animation {
	private final float mFromDegrees;
	private final float mToDegrees;
	private final float mCenterX;
	private final float mCenterY;
	private final float mDepthZ;
	private final boolean mReverse;
	private Camera mCamera;
 
	/**
	 * Creates a new 3D rotation on the Y axis. The rotation is defined by its
	 * start angle and its end angle. Both angles are in degrees. The rotation
	 * is performed around a center point on the 2D space, definied by a pair of
	 * X and Y coordinates, called centerX and centerY. When the animation
	 * starts, a translation on the Z axis (depth) is performed. The length of
	 * the translation can be specified, as well as whether the translation
	 * should be reversed in time.
	 *
	 * @param fromDegrees
	 *            the start angle of the 3D rotation
	 * @param toDegrees
	 *            the end angle of the 3D rotation
	 * @param centerX
	 *            the X center of the 3D rotation
	 * @param centerY
	 *            the Y center of the 3D rotation
	 * @param reverse
	 *            true if the translation should be reversed, false otherwise
	 */
	public Rotate3dAnimation(float fromDegrees, float toDegrees, float centerX, float centerY,
			float depthZ, boolean reverse) {
		mFromDegrees = fromDegrees;
		mToDegrees = toDegrees;
		mCenterX = centerX;
		mCenterY = centerY;
		mDepthZ = depthZ;
		mReverse = reverse;
	}
 
	@Override
	public void initialize(int width, int height, int parentWidth, int parentHeight) {
		super.initialize(width, height, parentWidth, parentHeight);
		mCamera = new Camera();
	}
 
	@Override
	protected void applyTransformation(float interpolatedTime, Transformation t) {
		final float fromDegrees = mFromDegrees;
		float degrees = fromDegrees + ((mToDegrees - fromDegrees) * interpolatedTime);
		final float centerX = mCenterX;
		final float centerY = mCenterY;
		final Camera camera = mCamera;
		final Matrix matrix = t.getMatrix();
		camera.save();
		//z轴上的景深
		if (mReverse) {
			camera.translate(0.0f, 0.0f, mDepthZ * interpolatedTime);
		} else {
			camera.translate(0.0f, 0.0f, mDepthZ * (1.0f - interpolatedTime));
		}
		camera.rotateY(degrees);
		camera.getMatrix(matrix);
		camera.restore();
		//camera.rotateY(degrees);其实围绕y轴旋转的坐标点是在（0,0）；
		//为了让其在围绕（centerX, centerY）点
		//preTranslate 作用为在rotateY开始之前先把坐标（centerX, centerY）移到中心点
		matrix.preTranslate(-centerX, -centerY);
		//postTranslate 当执行完rotateY后再把中心点移动回来
		matrix.postTranslate(centerX, centerY);
	}
}

layout文件：

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/layout"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
     >
 
    <ListView
        android:id="@+id/pic_list_view"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        >
    </ListView>
 
    <LinearLayout
        android:id="@+id/picture"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:clickable="true"
        android:orientation="vertical"
        android:visibility="gone"
        >
        <TextView
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:id="@+id/text"
            android:text="ddddddd"/>
        <ImageView
            android:layout_width="200dp"
            android:layout_height="200dp"
            android:src="@drawable/bird"
            />
        <Button android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="ddddddd"/>
 
    </LinearLayout>
 
</RelativeLayout>