add options to disable snap behavior.

Author: rwinzhang

TLYShyNavBar/TLYShyNavBarManager.h

@@ -76,6 +76,11 @@
  */
 @property (nonatomic) BOOL disable;
 
+/* Set NO to disable shyNavBar snap behavior
+ * Defaults to YES
+ */
+@property (nonatomic) BOOL snap;
+
 /* Use this to be notified about contraction and expansion events.
  */
 @property (nonatomic, weak) id<TLYShyNavBarManagerDelegate> delegate;

TLYShyNavBar/TLYShyNavBarManager.m

@@ -58,6 +58,7 @@ - (instancetype)init
         self.delegateProxy = [[TLYDelegateProxy alloc] initWithMiddleMan:self];
 
         /* Initialize defaults */
+        self.snap = YES;
         self.contracting = NO;
         self.previousContractionState = YES;
 
@@ -357,7 +358,9 @@ - (void)_handleScrollingEnded
     };
 
     self.resistanceConsumed = 0;
-    [self.navBarController snap:self.contracting completion:completion];
+    if (_snap) {
+        [self.navBarController snap:self.contracting completion:completion];
+    }
 }
 
 #pragma mark - KVO