Add showing error on failed swipe

material-intro-screen/src/main/java/agency/tango/materialintroscreen/ISlideErrorHandler.java

@@ -0,0 +1,5 @@
+package agency.tango.materialintroscreen;
+
+public interface ISlideErrorHandler {
+    void handleError();
+}

material-intro-screen/src/main/java/agency/tango/materialintroscreen/MaterialIntroActivity.java

@@ -330,6 +330,13 @@ public void onFinish() {
             }
         });
 
+        viewPager.registerSlideErrorHandler(new ISlideErrorHandler() {
+            @Override
+            public void handleError() {
+                errorOccurred(adapter.getItem(viewPager.getCurrentItem()));
+            }
+        });
+
         viewPager.addOnPageChangeListener(new ViewBehavioursOnPageChangeListener(adapter)
                 .registerViewTranslationWrapper(nextButtonTranslationWrapper)
                 .registerViewTranslationWrapper(backButtonTranslationWrapper)

material-intro-screen/src/main/java/agency/tango/materialintroscreen/widgets/SwipeableViewPager.java

@@ -7,6 +7,7 @@
 import android.view.KeyEvent;
 import android.view.MotionEvent;
 
+import agency.tango.materialintroscreen.ISlideErrorHandler;
 import agency.tango.materialintroscreen.adapter.SlidesAdapter;
 
 @SuppressWarnings("PMD.SingularField")
@@ -16,6 +17,7 @@ public class SwipeableViewPager extends CustomViewPager {
     private int currentIt;
     private boolean swipingAllowed;
     private boolean alphaExitTransitionEnabled = false;
+    private ISlideErrorHandler errorHandler;
 
     public SwipeableViewPager(Context context, AttributeSet attrs) {
         super(context, attrs);
@@ -55,13 +57,15 @@ public boolean onTouchEvent(final MotionEvent event) {
                 resolveSwipingRightAllowed();
                 return super.onTouchEvent(event);
             case (MotionEvent.ACTION_MOVE):
-                if (!swipingAllowed && startPos - event.getX() > 16) {
+                if (isSwipingNotAllowed(event)) {
+                    errorHandler.handleError();
                     return true;
                 }
                 return super.onTouchEvent(event);
             case (MotionEvent.ACTION_UP):
-                if (!swipingAllowed && startPos - event.getX() > 16) {
+                if (isSwipingNotAllowed(event)) {
                     smoothScrollTo(getWidth() * currentIt, 0);
+                    errorHandler.handleError();
                     return true;
                 }
                 startPos = 0;
@@ -81,6 +85,10 @@ public boolean executeKeyEvent(KeyEvent event) {
         return false;
     }
 
+    public void registerSlideErrorHandler(ISlideErrorHandler handler) {
+        errorHandler = handler;
+    }
+
     public void moveToNextPage() {
         setCurrentItem(getCurrentItem() + 1, true);
     }
@@ -105,6 +113,10 @@ public boolean alphaExitTransitionEnabled() {
         return alphaExitTransitionEnabled && swipingAllowed;
     }
 
+    private boolean isSwipingNotAllowed(MotionEvent event) {
+        return !swipingAllowed && startPos - event.getX() > 16;
+    }
+
     private void resolveSwipingRightAllowed() {
         if (getAdapter().shouldLockSlide(getCurrentItem())) {
             setSwipingRightAllowed(false);