[CRD iOS] Add support for three-finger gestures

remoting/ios/app/host_view_controller.mm

 // Copyright 2017 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.
 
 #if !defined(__has_feature) || !__has_feature(objc_arc)
 #error "This file requires ARC support."
 #endif
 
 #import "remoting/ios/app/host_view_controller.h"
 
 #include <memory>
 
 #import <GLKit/GLKit.h>
 
 #import "ios/third_party/material_components_ios/src/components/Buttons/src/MaterialButtons.h"
 #import "remoting/ios/client_gestures.h"
 #import "remoting/ios/client_keyboard.h"
 #import "remoting/ios/session/remoting_client.h"
 
 #include "base/strings/sys_string_conversions.h"
 #include "remoting/client/gesture_interpreter.h"
 #include "remoting/client/input/keyboard_interpreter.h"
 
 static const CGFloat kFabInset = 15.f;
 static const CGFloat kKeyboardAnimationTime = 0.3;
 
-@interface HostViewController ()<ClientKeyboardDelegate> {
+@interface HostViewController ()<ClientKeyboardDelegate,
+                                 ClientGesturesDelegate> {
   RemotingClient* _client;
   MDCFloatingButton* _floatingButton;
   ClientGestures* _clientGestures;
   ClientKeyboard* _clientKeyboard;
   CGSize _keyboardSize;
 }
 @end
 
 @implementation HostViewController
 
@@ skipping 55 matching lines @@
 - (void)viewDidDisappear:(BOOL)animated {
   [super viewDidDisappear:animated];
   [(GLKView*)self.view deleteDrawable];
 }
 
 - (void)viewWillAppear:(BOOL)animated {
   [super viewWillAppear:animated];
 
   _clientGestures =
       [[ClientGestures alloc] initWithView:self.view client:_client];
+  _clientGestures.delegate = self;
   [[NSNotificationCenter defaultCenter]
       addObserver:self
          selector:@selector(keyboardWillShow:)
              name:UIKeyboardWillShowNotification
            object:nil];
 
   [[NSNotificationCenter defaultCenter]
       addObserver:self
          selector:@selector(keyboardWillHide:)
              name:UIKeyboardWillHideNotification
@@ skipping 80 matching lines @@
 
 - (void)clientKeyboardShouldSend:(NSString*)text {
   _client.keyboardInterpreter->HandleTextEvent(base::SysNSStringToUTF8(text),
                                                0);
 }
 
 - (void)clientKeyboardShouldDelete {
   _client.keyboardInterpreter->HandleDeleteEvent(0);
 }
 
+#pragma mark - ClientGesturesDelegate
+
+- (void)keyboardShouldShow {
+  [self showKeyboard];
+}
+
+- (void)keyboardShouldHide {
+  [self hideKeyboard];
+}
+
 #pragma mark - Private
 
 - (void)didTap:(id)sender {
   // TODO(nicholss): The FAB is being used to launch an alert window with
   // more options. This is not ideal but it gets us an easy way to make a
   // modal window option selector. Replace this with a real menu later.
 
   UIAlertController* alert = [UIAlertController
       alertControllerWithTitle:@"Remote Settings"
                        message:nil
@@ skipping 50 matching lines @@
   // Target the alert menu at the top middle of the FAB.
   alert.popoverPresentationController.sourceRect = CGRectMake(
       _floatingButton.center.x, _floatingButton.frame.origin.y, 1.0, 1.0);
 
   alert.popoverPresentationController.permittedArrowDirections =
       UIPopoverArrowDirectionDown;
   [self presentViewController:alert animated:YES completion:nil];
 }
 
 @end