library/src/com/handmark/pulltorefresh/library/PullToRefreshBase.java
protected final void setHeaderScroll(int value) {
		if (DEBUG) {
			Log.d(LOG_TAG, "setHeaderScroll: " + value);
		}

		// Clamp value to with pull scroll range
		final int maximumPullScroll = getMaximumPullScroll();
		value = Math.min(maximumPullScroll, Math.max(-maximumPullScroll, value));

		if (mLayoutVisibilityChangesEnabled) {
			if (value < 0) {
				mHeaderLayout.setVisibility(View.VISIBLE);
			} else if (value > 0) {
				mFooterLayout.setVisibility(View.VISIBLE);
			} else {
				mHeaderLayout.setVisibility(View.INVISIBLE);
				mFooterLayout.setVisibility(View.INVISIBLE);
			}
		}

		if (USE_HW_LAYERS) {
			/**
			 * Use a Hardware Layer on the Refreshable View if we've scrolled at
			 * all. We don't use them on the Header/Footer Views as they change
			 * often, which would negate any HW layer performance boost.
			 */
			ViewCompat.setLayerType(mRefreshableViewWrapper, value != 0 ? View.LAYER_TYPE_HARDWARE
					: View.LAYER_TYPE_NONE);
		}

		switch (getPullToRefreshScrollDirection()) {
			case VERTICAL:
				scrollTo(0, value);
				break;
			case HORIZONTAL:
				scrollTo(value, 0);
				break;
		}
	}
protected final void setHeaderScroll(int value) {
		if (DEBUG) {
			Log.d(LOG_TAG, "setHeaderScroll: " + value);
		}

		// Clamp value to with pull scroll range
		final int maximumPullScroll = getMaximumPullScroll();
		value = Math.min(maximumPullScroll, Math.max(-maximumPullScroll, value));

		if (mLayoutVisibilityChangesEnabled) {
			if (value < 0) {
				mHeaderLayout.setVisibility(View.VISIBLE);
			} else if (value > 0) {
				mFooterLayout.setVisibility(View.VISIBLE);
			} else {
				mHeaderLayout.setVisibility(View.INVISIBLE);
				mFooterLayout.setVisibility(View.INVISIBLE);
			}
		}

		if (USE_HW_LAYERS) {
			/**
			 * Use a Hardware Layer on the Refreshable View if we've scrolled at
			 * all. We don't use them on the Header/Footer Views as they change
			 * often, which would negate any HW layer performance boost.
			 */
			ViewCompat.setLayerType(mRefreshableViewWrapper, value != 0 ? View.LAYER_TYPE_HARDWARE
					: View.LAYER_TYPE_NONE);
		}

		switch (getPullToRefreshScrollDirection()) {
			case VERTICAL:
				scrollTo(0, value);
				break;
			case HORIZONTAL:
				scrollTo(value, 0);
				break;
		}
	}
Helper method which just calls scrollTo() in the correct scrolling
direction.

@param value - New Scroll value