android 實現文字滾動效果

android 實現文字滾動效果 自己寫了個timer小計時器，textview文字上下翻動效果：

public class AutoTextView extends TextSwitcher implements
      ViewSwitcher.ViewFactory {

   private float mHeight;
   private Context mContext;
   //mInUp,mOutUp分別構成向下翻頁的進出動畫
   private Rotate3dAnimation mInUp;
   private Rotate3dAnimation mOutUp;
   
   //mInDown,mOutDown分別構成向下翻頁的進出動畫
   private Rotate3dAnimation mInDown;
   private Rotate3dAnimation mOutDown;
   
   public AutoTextView(Context context) {
      this(context, null);
      // TODO Auto-generated constructor stub
   }

   public AutoTextView(Context context, AttributeSet attrs) {
      super(context, attrs);
      // TODO Auto-generated constructor stub
      TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.auto3d);
      mHeight = a.getDimension(R.styleable.auto3d_textSize, 16);
      a.recycle();
      mContext = context;
      init();
   }

   private void init() {
      // TODO Auto-generated method stub
      setFactory(this);
      mInUp = createAnim(-90, 0 , true, true);
      mOutUp = createAnim(0, 90, false, true);
      mInDown = createAnim(90, 0 , true , false);
      mOutDown = createAnim(0, -90, false, false);
      //TextSwitcher主要用於文件切換，比如 從文字A 切換到 文字 B，
      //setInAnimation()後，A將執行inAnimation，
      //setOutAnimation()後，B將執行OutAnimation
        setInAnimation(mInUp);
        setOutAnimation(mOutUp);
   }
   
   private Rotate3dAnimation createAnim(float start, float end, boolean turnIn, boolean turnUp){
        final Rotate3dAnimation rotation = new Rotate3dAnimation(start, end, turnIn, turnUp);
        rotation.setDuration(800);
        rotation.setFillAfter(false);
        rotation.setInterpolator(new AccelerateInterpolator());
        return rotation;
   }

   //這裏返回的TextView，就是我們看到的View
   @Override
   public View makeView() {
      // TODO Auto-generated method stub
      TextView t = new TextView(mContext);
      t.setGravity(Gravity.CENTER);
      t.setTextSize(16);
      t.setMaxLines(1);
      t.setTextColor(mContext.getResources().getColor(R.color.textColor));
      return t;
   }
   //定義動作，向下滾動翻頁
   public void previous(){
      if(getInAnimation() != mInDown){
         setInAnimation(mInDown);
      }
      if(getOutAnimation() != mOutDown){
         setOutAnimation(mOutDown);
      }
   }
   //定義動作，向上滾動翻頁
   public void next(){
      if(getInAnimation() != mInUp){
         setInAnimation(mInUp);
      }
      if(getOutAnimation() != mOutUp){
         setOutAnimation(mOutUp);
      }
   }
   
    class Rotate3dAnimation extends Animation {
          private final float mFromDegrees;
          private final float mToDegrees;
          private float mCenterX;
          private float mCenterY;
          private final boolean mTurnIn;
          private final boolean mTurnUp;
          private Camera mCamera;

          public Rotate3dAnimation(float fromDegrees, float toDegrees, boolean turnIn, boolean turnUp) {
              mFromDegrees = fromDegrees;
              mToDegrees = toDegrees;
              mTurnIn = turnIn;
              mTurnUp = turnUp;
          }

          @Override
          public void initialize(int width, int height, int parentWidth, int parentHeight) {
              super.initialize(width, height, parentWidth, parentHeight);
              mCamera = new Camera();
              mCenterY = getHeight() / 2;
              mCenterX = getWidth() / 2;
          }
          
          @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 int derection = mTurnUp ? 1: -1;

              final Matrix matrix = t.getMatrix();

              camera.save();
              if (mTurnIn) {
                  camera.translate(0.0f, derection *mCenterY * (interpolatedTime - 1.0f), 0.0f);
              } else {
                  camera.translate(0.0f, derection *mCenterY * (interpolatedTime), 0.0f);
              }
              camera.rotateX(degrees);
              camera.getMatrix(matrix);
              camera.restore();

              matrix.preTranslate(-centerX, -centerY);
              matrix.postTranslate(centerX, centerY);
          }
    }

demo下載鏈接：

http://download.csdn.net/detail/u011275152/9696827