From e1baf34c5a457bf48e82a76a24c260d6ac27b578 Mon Sep 17 00:00:00 2001
From: Nikita Olifer <n.olifer@tinkoff.ru>
Date: Wed, 21 Feb 2018 13:34:38 +0300
Subject: [PATCH] Check for illegal offset values in ViewPagerAdapter.

---
 .../scrollingpagerindicator/ViewPagerAttacher.java    | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/library/src/main/java/ru/tinkoff/scrollingpagerindicator/ViewPagerAttacher.java b/library/src/main/java/ru/tinkoff/scrollingpagerindicator/ViewPagerAttacher.java
index 3a6dc71..9c9d479 100644
--- a/library/src/main/java/ru/tinkoff/scrollingpagerindicator/ViewPagerAttacher.java
+++ b/library/src/main/java/ru/tinkoff/scrollingpagerindicator/ViewPagerAttacher.java
@@ -45,7 +45,16 @@ public void onInvalidated() {
 
             @Override
             public void onPageScrolled(int position, float positionOffset, int positionOffsetPixel) {
-                indicator.onPageScrolled(position, positionOffset);
+                final float offset;
+                // ViewPager may emit negative positionOffset for very fast scrolling
+                if (positionOffset < 0) {
+                    offset = 0;
+                } else if (positionOffset > 1) {
+                    offset = 1;
+                } else {
+                    offset = positionOffset;
+                }
+                indicator.onPageScrolled(position, offset);
             }
 
             @Override