fixed #1

library/src/se/emilsjolander/flipview/FlipView.java

@@ -20,6 +20,7 @@
 import android.graphics.Rect;
 import android.support.v4.view.MotionEventCompat;
 import android.support.v4.view.VelocityTrackerCompat;
+import android.support.v4.widget.EdgeEffectCompat;
 import android.util.AttributeSet;
 import android.view.MotionEvent;
 import android.view.VelocityTracker;
@@ -120,6 +121,10 @@ public void onInvalidated() {
 	private Paint mShadePaint = new Paint();
 	private Paint mShinePaint = new Paint();
 
+	//edge glow effects
+	private EdgeEffectCompat mPreviousEdgeEffect;
+	private EdgeEffectCompat mNextEdgeEffect;
+
 	public FlipView(Context context) {
 		this(context, null);
 	}
@@ -155,6 +160,9 @@ private void init(){
         mShadePaint.setStyle(Style.FILL);
         mShinePaint.setColor(Color.WHITE);
         mShinePaint.setStyle(Style.FILL);
+
+        mPreviousEdgeEffect = new EdgeEffectCompat(context);
+        mNextEdgeEffect = new EdgeEffectCompat(context);
 	}
 
 	private void dataSetChanged() {
@@ -396,7 +404,12 @@ public boolean onTouchEvent(MotionEvent ev) {
                 deltaFlipDistance /= (getHeight()/FLIP_DISTANCE_PER_PAGE);
                 mFlipDistance += deltaFlipDistance;
 
-                bindFlipDistance();
+                float distanceBound = bindFlipDistance();
+                if(distanceBound > 0){
+                    mNextEdgeEffect.onPull(distanceBound/(isFlippingVertically()?getHeight():getWidth()));
+                }else if(distanceBound < 0){
+                    mPreviousEdgeEffect.onPull(-distanceBound/(isFlippingVertically()?getHeight():getWidth()));
+                }
                 invalidate();
             }
             break;
@@ -416,6 +429,9 @@ public boolean onTouchEvent(MotionEvent ev) {
 
                 mActivePointerId = INVALID_POINTER;
                 endFlip();
+
+                mNextEdgeEffect.onRelease();
+                mPreviousEdgeEffect.onRelease();
             }
             break;
         case MotionEventCompat.ACTION_POINTER_DOWN: {
@@ -449,8 +465,11 @@ protected void dispatchDraw(Canvas canvas) {
 			return;
 		}
 
+		boolean needsInvalidate = false;
+
 		if(!mScroller.isFinished() && mScroller.computeScrollOffset()){
 			mFlipDistance = mScroller.getCurrY();
+			needsInvalidate = true;
 		}
 
 		if(mIsFlipping || !mScroller.isFinished() || mPeakAnim != null){
@@ -459,6 +478,7 @@ protected void dispatchDraw(Canvas canvas) {
 			drawFlippingHalf(canvas);
 		}
 		else{
+			endScroll();
 			final int currentPage = getCurrentPageFloor();
 			if(mCurrentPage != currentPage){
 				postRemoveView(getChildAt(0));
@@ -473,14 +493,54 @@ protected void dispatchDraw(Canvas canvas) {
 			v.draw(canvas);
 		}
 
-		if(mScroller.isFinished()){
-			if(!mIsFlipping && mPeakAnim == null){
-				endScroll();
+		needsInvalidate |= drawEdgeEffects(canvas);
+
+		if(needsInvalidate) {
+			invalidate();
+		}
+	}
+
+	private boolean drawEdgeEffects(Canvas canvas) {
+		return drawPreviousEdgeEffect(canvas) | drawNextEdgeEffect(canvas);
+	}
+
+	private boolean drawNextEdgeEffect(Canvas canvas) {
+		boolean needsMoreDrawing = false;
+		if(!mNextEdgeEffect.isFinished()){
+			canvas.save();
+			if(isFlippingVertically()){
+				mNextEdgeEffect.setSize(getWidth(), getHeight());
+				canvas.rotate(180);
+				canvas.translate(-getWidth(), -getHeight());
 			}
+			else{
+				mNextEdgeEffect.setSize(getHeight(), getWidth());
+				canvas.rotate(90);
+				canvas.translate(0, -getWidth());
+			}
+			needsMoreDrawing = mNextEdgeEffect.draw(canvas);
+			canvas.restore();
 		}
-		else {
-			invalidate();
+		return needsMoreDrawing;
+	}
+
+	private boolean drawPreviousEdgeEffect(Canvas canvas) {
+		boolean needsMoreDrawing = false;
+		if(!mPreviousEdgeEffect.isFinished()){
+			canvas.save();
+			if(isFlippingVertically()){
+				mPreviousEdgeEffect.setSize(getWidth(), getHeight());
+				canvas.rotate(0);
+			}
+			else{
+				mPreviousEdgeEffect.setSize(getHeight(), getWidth());
+				canvas.rotate(270);
+				canvas.translate(-getHeight(), 0);
+			}
+			needsMoreDrawing = mPreviousEdgeEffect.draw(canvas);
+			canvas.restore();
 		}
+		return needsMoreDrawing;
 	}
 
 	/**
@@ -705,15 +765,17 @@ public void run() {
 		});
 	}
 
-	private void bindFlipDistance(){
+	private float bindFlipDistance(){
 		final int minFlipDistance = 0;
 		final int maxFlipDistance = (mPageCount-1)*FLIP_DISTANCE_PER_PAGE;
+		final float flipDistanceBeforeBinding = mFlipDistance;
 		if(mFlipDistance < minFlipDistance){
         	mFlipDistance = 0;
         }
         else if(mFlipDistance > maxFlipDistance){
         	mFlipDistance = maxFlipDistance;
         }
+		return flipDistanceBeforeBinding - mFlipDistance;
 	}
 
 	private void onSecondaryPointerUp(MotionEvent ev) {

sample/res/layout/page.xml

@@ -2,7 +2,7 @@
 <FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
-    android:background="@android:color/white" >
+    android:background="#ff3333" >
 
     <Button
         android:id="@+id/first_page"

sample/src/se/emilsjolander/flipview/MainActivity.java

@@ -33,8 +33,8 @@ public void onPageRequested(int page) {
 	@Override
 	public void onFlippedToPage(FlipView v, int position, long id) {
 		Toast.makeText(getBaseContext(), "Page: "+position, Toast.LENGTH_SHORT).show();
-		if(position > mFlipView.getPageCount()-3){
-			mAdapter.addItems(5);
+		if(position > mFlipView.getPageCount()-3 && mFlipView.getPageCount()<30){
+			//mAdapter.addItems(5);
 		}
 	}