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Flikrkr/ReaderView.m

@@ -8,6 +8,12 @@
 
 #import "ReaderView.h"
 
+@interface ReaderView ()
+
+@property (nonatomic, assign) int currentIndex;
+
+@end
+
 @implementation ReaderView
 
 - (id)initWithFrame:(CGRect)frame
@@ -29,7 +35,35 @@
  */
 -(void)displayPageAtIndex:(int)index
 {
+    if (index >= 0 && index < [self.delegate numberOfPages]) {
         UIView * view = [self.delegate pageAtIndex:index];
         [self addSubview:view];
+        self.currentIndex = index;
+    }
+}
+- (void)layoutSubviews
+{
+    if (!self.gestureRecognizers.count) {
+        UISwipeGestureRecognizer * previousPageRecognizer =
+        [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(previousPage)];
+        previousPageRecognizer.direction = UISwipeGestureRecognizerDirectionRight;
+        [self addGestureRecognizer:previousPageRecognizer];
+        
+        UISwipeGestureRecognizer * nextPageRecognizer =
+        [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(nextPage)];
+        nextPageRecognizer.direction = UISwipeGestureRecognizerDirectionLeft;
+        [self addGestureRecognizer:nextPageRecognizer];
+        
+        self.userInteractionEnabled = YES;
+    }
+}
+
+- (void) previousPage
+{
+    [self displayPageAtIndex:self.currentIndex-1];
+}
+- (void) nextPage
+{
+    [self displayPageAtIndex:self.currentIndex+1];
 }
 @end