ListViewItemAnimations.java 文件源码

/**
 * Sets the horizontal position and translucency of the view being swiped.
 */
@SuppressLint("NewApi")
private void setSwipePosition(View view, float deltaX) {
    float fraction = Math.abs(deltaX) / view.getWidth();
    if (isRuntimePostGingerbread()) {
        view.setTranslationX(deltaX);
        view.setAlpha(1 - fraction);
    } else {
        // Hello, Gingerbread!
        TranslateAnimation swipeAnim = new TranslateAnimation(deltaX, deltaX, 0, 0);
        mCurrentX = deltaX;
        mCurrentAlpha = (1 - fraction);
        AlphaAnimation alphaAnim = new AlphaAnimation(mCurrentAlpha, mCurrentAlpha);
        AnimationSet set = new AnimationSet(true);
        set.addAnimation(swipeAnim);
        set.addAnimation(alphaAnim);
        set.setFillAfter(true);
        set.setFillEnabled(true);
        view.startAnimation(set);
    }
}