android.view.View#setPivotY ( )源码实例Demo

/**
	 * Called each {@link #transformPage(View, float)} before {{@link #onTransform(View, float)}.
	 * <p>
	 * The default implementation attempts to reset all view properties. This is useful when toggling transforms that do
	 * not modify the same page properties. For instance changing from a transformation that applies rotation to a
	 * transformation that fades can inadvertently leave a fragment stuck with a rotation or with some degree of applied
	 * alpha.
	 *
	 * @param page
	 *            Apply the transformation to this page
	 * @param position
	 *            Position of page relative to the current front-and-center position of the pager. 0 is front and
	 *            center. 1 is one full page position to the right, and -1 is one page position to the left.
	 */
	protected void onPreTransform(View page, float position) {
		final float width = page.getWidth();

		page.setRotationX(0);
		page.setRotationY(0);
		page.setRotation(0);
		page.setScaleX(1);
		page.setScaleY(1);
		page.setPivotX(0);
		page.setPivotY(0);
		page.setTranslationY(0);
		page.setTranslationX(isPagingEnabled() ? 0f : -width * position);

		if (hideOffscreenPages()) {
			page.setAlpha(position <= -1f || position >= 1f ? 0f : 1f);
//			page.setEnabled(false);
		} else {
//			page.setEnabled(true);
			page.setAlpha(1f);
		}
	}
 

/**
 * Called each {@link #transformPage(android.view.View, float)} before {{@link #onTransform(android.view.View, float)} is called.
 * 
 * @param view
 * @param position
 */
protected void onPreTransform(View view, float position) {
	final float width = view.getWidth();

	view.setRotationX(0);
	view.setRotationY(0);
	view.setRotation(0);
	view.setScaleX(1);
	view.setScaleY(1);
	view.setPivotX(0);
	view.setPivotY(0);
	view.setTranslationY(0);
	view.setTranslationX(isPagingEnabled() ? 0f : -width * position);

	if (hideOffscreenPages()) {
		view.setAlpha(position <= -1f || position >= 1f ? 0f : 1f);
	} else {
		view.setAlpha(1f);
	}
}
 

@Override
public void screenScrolled(View v, float progress) {
    float rotation =
            (rotateUp ? TRANSITION_SCREEN_ROTATION : -TRANSITION_SCREEN_ROTATION) * progress;

    float translationX = v.getMeasuredWidth() * progress;

    float rotatePoint =
            (v.getMeasuredWidth() * 0.5f)
                    / (float) Math.tan(Math.toRadians((double) (TRANSITION_SCREEN_ROTATION * 0.5f)));

    v.setPivotX(v.getMeasuredWidth() * 0.5f);
    if (rotateUp) {
        v.setPivotY(-rotatePoint);
    } else {
        v.setPivotY(v.getMeasuredHeight() + rotatePoint);
    }
    v.setRotation(rotation);
    v.setTranslationX(translationX);
}
 

private void hideHint(final View view) {
    view.setPivotX(0);
    view.setPivotY(view.getHeight());

    Animator iconAnim = ObjectAnimator.ofPropertyValuesHolder(view,
            PropertyValuesHolder.ofFloat(View.ALPHA, 1f, 0f),
            PropertyValuesHolder.ofFloat(View.SCALE_Y, 1f, 0f));
    iconAnim.addListener(new AnimatorListenerAdapter() {
        @Override
        public void onAnimationEnd(Animator animation) {
            super.onAnimationEnd(animation);
            view.setVisibility(View.INVISIBLE);
        }
    });
    iconAnim.start();
}
 

@Override
protected void onTransform(View view, float position) {
	final float scale = position < 0 ? position + 1f : Math.abs(1f - position);
	view.setScaleX(scale);
	view.setScaleY(scale);
	view.setPivotX(view.getWidth() * 0.5f);
	view.setPivotY(view.getHeight() * 0.5f);
	view.setAlpha(position < -1f || position > 1f ? 0f : 1f - (scale - 1f));
}
 

@Override
protected void onTransform(View view, float position) {
    final float height = view.getHeight();
    final float width = view.getWidth();
    final float scale = min(position > 0 ? 1f : Math.abs(1f + position), 0.5f);

    view.setScaleX(scale);
    view.setScaleY(scale);
    view.setPivotX(width * 0.5f);
    view.setPivotY(height * 0.5f);
    view.setTranslationX(position > 0 ? width * position : -width * position * 0.25f);
}
 

@Override
protected void onTransform(View view, float position) {
	final float width = view.getWidth();
	final float height = view.getHeight();
	final float rotation = ROT_MOD * position * -1.25f;

	view.setPivotX(width * 0.5f);
	view.setPivotY(height);
	view.setRotation(rotation);
}
 

/**
 * 放大动画
 *
 * @param view
 */
public static void zoomOut(final View view, float scale) {
    view.setPivotY(view.getHeight());
    view.setPivotX(view.getWidth() / 2);
    AnimatorSet mAnimatorSet = new AnimatorSet();

    ObjectAnimator mAnimatorScaleX = ObjectAnimator.ofFloat(view, "scaleX", scale, 1.0f);
    ObjectAnimator mAnimatorScaleY = ObjectAnimator.ofFloat(view, "scaleY", scale, 1.0f);
    ObjectAnimator mAnimatorTranslateY = ObjectAnimator.ofFloat(view, "translationY", view.getTranslationY(), 0);

    mAnimatorSet.play(mAnimatorTranslateY).with(mAnimatorScaleX);
    mAnimatorSet.play(mAnimatorScaleX).with(mAnimatorScaleY);
    mAnimatorSet.setDuration(300);
    mAnimatorSet.start();
}
 

@Override
public void transform(View view, float position) {
    int width = view.getMeasuredWidth(), height = view.getMeasuredHeight();
    view.setPivotX(width / 2.0f);
    view.setPivotY(height / 2.0f);
    view.setTranslationX(width * position * mOffsetXPercent);
    view.setRotationY(Math.signum(position) * (float)(Math.log(Math.abs(position) + 1) / Math.log(3) * - mYProjection));
    view.setScaleY(1 + mScaleYFactor * Math.abs(position));
}
 

@Override
protected void onTransform(View view, float position) {
	final float scale = position < 0 ? position + 1f : Math.abs(1f - position);
	view.setScaleX(scale);
	view.setScaleY(scale);
	view.setPivotX(view.getWidth() * 0.5f);
	view.setPivotY(view.getHeight() * 0.5f);
	view.setAlpha(position < -1f || position > 1f ? 0f : 1f - (scale - 1f));
}
 

@Override
protected void onTransform(View view, float position) {
	if (position >= -1 || position <= 1) {
		// Modify the default slide transition to shrink the page as well
		final float height = view.getHeight();
		final float width = view.getWidth();
		final float scaleFactor = Math.max(MIN_SCALE, 1 - Math.abs(position));
		final float vertMargin = height * (1 - scaleFactor) / 2;
		final float horzMargin = width * (1 - scaleFactor) / 2;

		// Center vertically
		view.setPivotY(0.5f * height);
		view.setPivotX(0.5f * width);

		if (position < 0) {
			view.setTranslationX(horzMargin - vertMargin / 2);
		} else {
			view.setTranslationX(-horzMargin + vertMargin / 2);
		}

		// Scale the page down (between MIN_SCALE and 1)
		view.setScaleX(scaleFactor);
		view.setScaleY(scaleFactor);

		// Fade the page relative to its size.
		view.setAlpha(MIN_ALPHA + (scaleFactor - MIN_SCALE) / (1 - MIN_SCALE) * (1 - MIN_ALPHA));
	}
}
 

void setView(View view, int width, int height) {
    LayoutParams params = new LayoutParams(width, height, Gravity.CENTER_HORIZONTAL);
    addView(view, params);

    // Setting temporary pivotal point, see #onMeasure()
    origPivotY = view.getPivotY();
    view.setPivotY(0f);
}
 

@Override
protected void onTransform(View view, float position) {
	final float scale = position < 0 ? position + 1f : Math.abs(1f - position);
	view.setScaleX(scale);
	view.setScaleY(scale);
	view.setPivotX(view.getWidth() * 0.5f);
	view.setPivotY(view.getHeight() * 0.5f);
	view.setAlpha(position < -1f || position > 1f ? 0f : 1f - (scale - 1f));
}
 

@Override
protected void onTransform(View view, float position) {
	final float rotation = -180f * position;

	view.setAlpha(rotation > 90f || rotation < -90f ? 0f : 1f);
	view.setPivotX(view.getWidth() * 0.5f);
	view.setPivotY(view.getHeight() * 0.5f);
	view.setRotationX(rotation);
}
 

@Override
public void initView(View item, int position, int scrollDirection) {
    item.setPivotX(item.getWidth() / 2);
    item.setPivotY(item.getHeight() / 2);
    item.setScaleX(INITIAL_SCALE_FACTOR);
    item.setScaleY(INITIAL_SCALE_FACTOR);
}
 

@Override
protected void onTransform(View view, float position) {
    final float scale = 1f + Math.abs(position);
    view.setScaleX(scale);
    view.setScaleY(scale);
    view.setPivotX(view.getWidth() * 0.5f);
    view.setPivotY(view.getHeight() * 0.5f);
    view.setAlpha(position < -1f || position > 1f ? 0f : 1f - (scale - 1f));
    if (position == -1) {
        view.setTranslationX(view.getWidth() * -1);
    }
}
 

@Override
protected void onTransform(View view, float position) {
    final float width = view.getWidth();
    final float height = view.getHeight();
    final float rotation = ROT_MOD * position * -1.25f;

    view.setPivotX(width * 0.5f);
    view.setPivotY(height);
    view.setRotation(rotation);
}
 

@Override
protected void onTransform(View view, float position) {
	// Rotate the fragment on the left or right edge
	view.setPivotX(position > 0 ? 0 : view.getWidth());
	view.setPivotY(0);
	view.setRotationY(-90f * position);
}
 

@Override
protected void onTransform(View view, float position) {
	if (position >= -1 || position <= 1) {
		// Modify the default slide transition to shrink the page as well
		final float height = view.getHeight();
		final float width = view.getWidth();
		final float scaleFactor = Math.max(MIN_SCALE, 1 - Math.abs(position));
		final float vertMargin = height * (1 - scaleFactor) / 2;
		final float horzMargin = width * (1 - scaleFactor) / 2;

		// Center vertically
		view.setPivotY(0.5f * height);
		view.setPivotX(0.5f * width);

		if (position < 0) {
			view.setTranslationX(horzMargin - vertMargin / 2);
		} else {
			view.setTranslationX(-horzMargin + vertMargin / 2);
		}

		// Scale the page down (between MIN_SCALE and 1)
		view.setScaleX(scaleFactor);
		view.setScaleY(scaleFactor);

		// Fade the page relative to its size.
		view.setAlpha(MIN_ALPHA + (scaleFactor - MIN_SCALE) / (1 - MIN_SCALE) * (1 - MIN_ALPHA));
	}
}
 

@Override
   protected void onTransform(View view, float position) {
	view.setPivotX(position < 0f ? view.getWidth() : 0f);
	view.setPivotY(view.getHeight() * 0.5f);
	view.setRotationY(90f * position);
}