Added pre- and post-animation hooks for subclass usage.

cbpowell · May 17, 2014 · 4e7d9bb · 4e7d9bb
1 parent 008982d
commit 4e7d9bb
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Showing 2 changed files with 53 additions and 3 deletions.
diff --git a/MarqueeLabel.h b/MarqueeLabel.h
@@ -253,6 +253,7 @@ typedef NS_ENUM(NSUInteger, MarqueeType) {
 
 - (void)pauseLabel;
 
+
 /** Un-pauses a previously paused text scrolling animation
  
  @see pauseLabel
@@ -261,6 +262,33 @@ typedef NS_ENUM(NSUInteger, MarqueeType) {
 - (void)unpauseLabel;
 
 
+/** Called when the label animation has finished, and the label is at the home position.
+ 
+ The default implementation of this method does nothing. Subclasses may override this method in order to perform any custom actions before
+ the label animation begins. This is only called in the event that the conditions for scrolling to begin are met.
+ 
+ @since Available in 1.5.0 and later.
+ */
+
+- (void)labelWillBeginScroll;
+
+
+/** Called when the label animation has finished, and the label is at the home position.
+ 
+ The default implementation of this method does nothing. Subclasses may override this method in order to perform any custom actions after
+ the label animation is complete, and before the next animation would begin (assuming the conditions are met).
+ 
+ @param A Boolean that indicates whether or not the scroll animation actually finished before the completion handler was called.
+ @since Available in 1.5.0 and later.
+ 
+ @warning This method will be called, and the `finished` parameter will be `NO`, when any property changes that would cause the label scrolling to be
+ reset are made. This includes changes to label text and font/font size changes.
+ */
+
+- (void)labelReturnedToHome:(BOOL)finished;
+
+
+
 ////////////////////////////////////////////////////////////////////////////////
 /// @name Label States
 ////////////////////////////////////////////////////////////////////////////////

diff --git a/MarqueeLabel.m b/MarqueeLabel.m
@@ -566,12 +566,13 @@ - (void)scrollAwayWithInterval:(NSTimeInterval)interval delayAmount:(NSTimeInter
         return;
     }
 
-    // Perform animation
-    self.awayFromHome = YES;
-
     [self.subLabel.layer removeAllAnimations];
     [self.layer removeAllAnimations];
 
+    // Call pre-animation method
+    [self labelWillBeginScroll];
+
+    // Animate
     [UIView animateWithDuration:interval
                           delay:delayAmount
                         options:self.animationCurve
@@ -583,6 +584,9 @@ - (void)scrollAwayWithInterval:(NSTimeInterval)interval delayAmount:(NSTimeInter
                              [self scrollHomeWithInterval:interval delayAmount:delayAmount];
                          }
                      }];
+
+    // Move to away state
+    self.awayFromHome = YES;
 }
 
 - (void)scrollHomeWithInterval:(NSTimeInterval)interval {
@@ -605,9 +609,13 @@ - (void)scrollHomeWithInterval:(NSTimeInterval)interval delayAmount:(NSTimeInter
                          self.subLabel.frame = self.homeLabelFrame;
                      }
                      completion:^(BOOL finished){
+                         // Call completion method
+                         [self labelReturnedToHome:finished];
+
                          if (finished) {
                              // Set awayFromHome
                              self.awayFromHome = NO;
+
                              if (!self.tapToScroll && !self.holdScrolling) {
                                  [self scrollAwayWithInterval:interval];
                              }
@@ -633,6 +641,9 @@ - (void)scrollContinuousWithInterval:(NSTimeInterval)interval after:(NSTimeInter
 
     self.awayFromHome = YES;
 
+    // Call pre-animation method
+    [self labelWillBeginScroll];
+
     // Animate
     [UIView animateWithDuration:interval
                           delay:delayAmount
@@ -646,6 +657,9 @@ - (void)scrollContinuousWithInterval:(NSTimeInterval)interval after:(NSTimeInter
                          }
                      }
                      completion:^(BOOL finished) {
+                         // Call completion method
+                         [self labelReturnedToHome:finished];
+
                          if (finished && !self.tapToScroll && !self.holdScrolling) {
                              self.awayFromHome = NO;
                              [self scrollContinuousWithInterval:interval after:delayAmount];
@@ -723,6 +737,14 @@ - (void)labelWasTapped:(UITapGestureRecognizer *)recognizer {
     }
 }
 
+- (void)labelWillBeginScroll {
+    return;
+}
+
+- (void)labelReturnedToHome:(BOOL)finished {
+    return;
+}
+
 #pragma mark - Modified UILabel Getters/Setters
 
 - (NSString *)text {