[iOS] Upstream ios/chrome/browser/find_in_page

ios/web/public/web_state/crw_web_view_scroll_view_proxy.h

+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef IOS_WEB_PUBLIC_WEB_STATE_CRW_WEB_VIEW_SCROLL_VIEW_PROXY_H_
+#define IOS_WEB_PUBLIC_WEB_STATE_CRW_WEB_VIEW_SCROLL_VIEW_PROXY_H_
+
+#import <UIKit/UIKit.h>
+
+@protocol CRWWebViewScrollViewProxyObserver;
+
+// Provides an interface for web state observers to access the WebState's
+// UIScrollView in a limited and controlled manner.
+// This class is designed to limit lifetime of the UIScrollView such that it is
+// not retained beyond WebState. It is also a way to tunnel UIScrollViewDelegate
+// callbacks.
+// NOTE: The API exposed by the proxy class isn't intended to be restrictive.
+// The features needing to access other UIScrollView properties and methods
+// needed to drive the UIScrollView are free to extend the proxy class as
+// needed.
+// The class forwards some of the methods onto the UIScrollView. For more
+// information look at the UIScrollView documentation.
+@interface CRWWebViewScrollViewProxy : NSObject<UIScrollViewDelegate>
+@property(nonatomic, assign) CGPoint contentOffset;
+@property(nonatomic, assign) UIEdgeInsets contentInset;
+@property(nonatomic, readonly) BOOL isZooming;
+@property(nonatomic, assign) UIEdgeInsets scrollIndicatorInsets;
+@property(nonatomic, assign) CGSize contentSize;
+@property(nonatomic, readonly) CGRect frame;
+@property(nonatomic, getter=isScrollEnabled) BOOL scrollEnabled;
+@property(nonatomic, assign) BOOL bounces;
+@property(nonatomic, readonly) UIPanGestureRecognizer* panGestureRecognizer;
+// Returns the scrollview's gesture recognizers.
+@property(nonatomic, readonly) NSArray* gestureRecognizers;
+
+// Calls UIScrollView's implementation of setContentInset: directly. This
+// bypasses a very slow update path in UIWebView.
+- (void)setContentInsetFast:(UIEdgeInsets)contentInset;
+
+- (void)addGestureRecognizer:(UIGestureRecognizer*)gestureRecognizer;
+- (void)removeGestureRecognizer:(UIGestureRecognizer*)gestureRecognizer;
+- (void)setContentOffset:(CGPoint)contentOffset animated:(BOOL)animated;
+
+// Used by the CRWWebViewProxy to set the UIScrollView to be managed.
+- (void)setScrollView:(UIScrollView*)scrollView;
+
+// Copies all display properties that can be set on a CRWWebViewScrollViewProxy
+// from the underlying UIScrollView into |scrollView|.
+- (void)copyPropertiesToScrollView:(UIScrollView*)scrollView;
+
+// Adds |observer| to subscribe to change notifications.
+- (void)addObserver:(id<CRWWebViewScrollViewProxyObserver>)observer;
+
+// Removes |observer| as a subscriber for change notifications.
+- (void)removeObserver:(id<CRWWebViewScrollViewProxyObserver>)observer;
+
+@end
+
+// A protocol to be implemented by objects to listen for changes to the
+// UIScrollView.
+// This is an exact mirror of the UIScrollViewDelegate callbacks. For more
+// information look at the UIScrollViewDelegate documentation.
+@protocol CRWWebViewScrollViewObserver<NSObject>
+@optional
+- (void)webViewScrollViewDidScroll:
+        (CRWWebViewScrollViewProxy*)webViewScrollViewProxy;
+- (void)webViewScrollViewWillBeginDragging:
+        (CRWWebViewScrollViewProxy*)webViewScrollViewProxy;
+- (void)webViewScrollViewWillEndDragging:
+            (CRWWebViewScrollViewProxy*)webViewScrollViewProxy
+                            withVelocity:(CGPoint)velocity
+                     targetContentOffset:(inout CGPoint*)targetContentOffset;
+- (void)webViewScrollViewDidEndDragging:
+            (CRWWebViewScrollViewProxy*)webViewScrollViewProxy
+                         willDecelerate:(BOOL)decelerate;
+- (void)webViewScrollViewDidEndScrollingAnimation:
+        (CRWWebViewScrollViewProxy*)webViewScrollViewProxy;
+- (void)webViewScrollViewDidEndDecelerating:
+        (CRWWebViewScrollViewProxy*)webViewScrollViewProxy;
+- (BOOL)webViewScrollViewShouldScrollToTop:
+        (CRWWebViewScrollViewProxy*)webViewScrollViewProxy;
+@end
+
+// A protocol to be implemented by objects to listen for changes to the
+// CRWWebViewScrollViewProxyObserver.
+// It inherit from CRWWebViewScrollViewScrollViewObserver which only implements
+// methods for listening to scrollview changes.
+@protocol CRWWebViewScrollViewProxyObserver<CRWWebViewScrollViewObserver>
+@optional
+// Called when the underlying scrollview of the proxy is set.
+- (void)webViewScrollViewProxyDidSetScrollView:
+        (CRWWebViewScrollViewProxy*)webViewScrollViewProxy;
+@end
+
+#endif  // IOS_WEB_PUBLIC_WEB_STATE_CRW_WEB_VIEW_SCROLL_VIEW_PROXY_H_