Fixed fatal crash when no indicator was used.

Author: turing-tech

app/app.iml

@@ -90,7 +90,7 @@
       <excludeFolder url="file://$MODULE_DIR$/build/outputs" />
       <excludeFolder url="file://$MODULE_DIR$/build/tmp" />
     </content>
-    <orderEntry type="jdk" jdkName="Android API 23 Platform (1)" jdkType="Android SDK" />
+    <orderEntry type="jdk" jdkName="Android API 23 Platform" jdkType="Android SDK" />
     <orderEntry type="sourceFolder" forTests="false" />
     <orderEntry type="library" exported="" name="library-2.4.0" level="project" />
     <orderEntry type="library" exported="" name="appcompat-v7-23.0.0" level="project" />

lib/src/main/java/com/turingtechnologies/materialscrollbar/MaterialScrollBar.java

@@ -305,7 +305,7 @@ public float calculateScrollProgress(RecyclerView recyclerView) {
             int indexOfLastFullyVisibleItemInFirstSection = numItemsInList - numScrollableSectionsInList - 1;
 
             int currentSection = lastFullyVisiblePosition - indexOfLastFullyVisibleItemInFirstSection;
-            if(sectionIndicator.getVisibility() == VISIBLE){
+            if(sectionIndicator != null && sectionIndicator.getVisibility() == VISIBLE){
                 if(currentSection == 0){
                     sectionIndicator.setCharacter(((INameableAdapter)recyclerView.getAdapter()).getCharacterForElement(currentSection));
                 } else {