Add a menu item to toggle the incognito mode in ios_web_view_shell.

ios/web_view/shell/shell_view_controller.m

Index: ios/web_view/shell/shell_view_controller.m
diff --git a/ios/web_view/shell/shell_view_controller.m b/ios/web_view/shell/shell_view_controller.m
index 3815f50d1358f9898b42881d4c3c358682fd2d69..9483b06802a1bcda7349abf35819f8930841124b 100644
--- a/ios/web_view/shell/shell_view_controller.m
+++ b/ios/web_view/shell/shell_view_controller.m
@@ -37,12 +37,14 @@ NSString* const kWebViewShellJavaScriptDialogTextFieldAccessibiltyIdentifier =
 @property(nonatomic, strong) CWVWebView* webView;
 // Handles the translation of the content displayed in |webView|.
 @property(nonatomic, strong) ShellTranslationDelegate* translationDelegate;
+// Whether it's in the incognito mode.
+@property(nonatomic) BOOL isIncognito;

[michaeldo, 2017/05/31 21:21:10]

I actually think it would be better to either use
!_webView.configuration.isPersistent directly or make this readonly and return
that value so we don't need to worry about setting it.

[Hiroshi Ichikawa, 2017/06/01 01:20:37]

Done.

 
 - (void)back;
 - (void)forward;
 - (void)stopLoading;
 // Disconnects and release the |webView|.
-- (void)resetWebView;
+- (void)removeWebView;
 @end
 
 @implementation ShellViewController
@@ -54,6 +56,7 @@ NSString* const kWebViewShellJavaScriptDialogTextFieldAccessibiltyIdentifier =
 @synthesize toolbar = _toolbar;
 @synthesize webView = _webView;
 @synthesize translationDelegate = _translationDelegate;
+@synthesize isIncognito = _isIncognito;
 
 - (void)viewDidLoad {
   [super viewDidLoad];
@@ -157,33 +160,7 @@ NSString* const kWebViewShellJavaScriptDialogTextFieldAccessibiltyIdentifier =
 
   [CWVWebView setUserAgentProduct:@"Dummy/1.0"];
 
-  CWVWebViewConfiguration* configuration =
-      [CWVWebViewConfiguration defaultConfiguration];
-  self.webView = [[CWVWebView alloc] initWithFrame:[_containerView bounds]
-                                     configuration:configuration];
-  // Gives a restoration identifier so that state restoration works.
-  _webView.restorationIdentifier = @"webView";
-  _webView.navigationDelegate = self;
-  _webView.UIDelegate = self;
-  _translationDelegate = [[ShellTranslationDelegate alloc] init];
-  _webView.translationController.delegate = _translationDelegate;
-
-  [_webView setAutoresizingMask:UIViewAutoresizingFlexibleWidth |
-                                UIViewAutoresizingFlexibleHeight];
-  [_containerView addSubview:_webView];
-
-  [_webView addObserver:self
-             forKeyPath:@"canGoBack"
-                options:NSKeyValueObservingOptionNew
-                context:nil];
-  [_webView addObserver:self
-             forKeyPath:@"canGoForward"
-                options:NSKeyValueObservingOptionNew
-                context:nil];
-
-  NSURLRequest* request = [NSURLRequest
-      requestWithURL:[NSURL URLWithString:@"https://www.google.com/"]];
-  [_webView loadRequest:request];
+  [self createWebViewWithConfiguration:[self createConfiguration]];

[michaeldo, 2017/05/31 21:21:09]

I think explicitly using [CWVWebViewConfiguration defaultConfiguration] here is
clearer about the default state and that helper method can be removed.

[Hiroshi Ichikawa, 2017/06/01 01:20:37]

Done.

 }
 
 - (void)observeValueForKeyPath:(NSString*)keyPath
@@ -239,20 +216,73 @@ NSString* const kWebViewShellJavaScriptDialogTextFieldAccessibiltyIdentifier =
                                          [weakSelf.webView reload];
                                        }]];
 
-  // Removes the web view from the view hierarchy and releases it. For
-  // testing deallocation behavior, because there have been multiple crash bugs
-  // on deallocation of CWVWebView.
+  // Toggles the incognito mode.
+  NSString* incognitoActionTitle =
+      _isIncognito ? @"Exit incognito" : @"Enter incognito";
   [alertController
-      addAction:[UIAlertAction actionWithTitle:@"Deallocate web view"
-                                         style:UIAlertActionStyleDefault
-                                       handler:^(UIAlertAction* action) {
-                                         [weakSelf resetWebView];
-                                       }]];
+      addAction:[UIAlertAction
+                    actionWithTitle:incognitoActionTitle
+                              style:UIAlertActionStyleDefault
+                            handler:^(UIAlertAction* action) {
+                              [weakSelf removeWebView];
+                              weakSelf.isIncognito = !weakSelf.isIncognito;
+                              [weakSelf createWebViewWithConfiguration:
+                                            [weakSelf createConfiguration]];
+                            }]];
+
+  // Removes the web view from the view hierarchy, releases it, and recreates
+  // the web view with the same configuration. This is for testing deallocation
+  // and sharing configuration, because there have been multiple bugs on these

[michaeldo, 2017/05/31 21:21:10]

I think you can remove the ", because there have been multiple bugs on these
features" piece of this comment. Testing the feature in the shell is a good idea
even if there were never any bugs in them :)

[Hiroshi Ichikawa, 2017/06/01 01:20:36]

Done.

+  // features.
+  [alertController
+      addAction:[UIAlertAction
+                    actionWithTitle:@"Recreate web view"
+                              style:UIAlertActionStyleDefault
+                            handler:^(UIAlertAction* action) {
+                              CWVWebViewConfiguration* configuration =
+                                  weakSelf.webView.configuration;
+                              [weakSelf removeWebView];
+                              [weakSelf
+                                  createWebViewWithConfiguration:configuration];
+                            }]];
 
   [self presentViewController:alertController animated:YES completion:nil];
 }
 
-- (void)resetWebView {
+- (CWVWebViewConfiguration*)createConfiguration {

[michaeldo, 2017/05/31 21:21:10]

Per comment above, I don't think we need this. We can just toggle in the handler
block above.

[Hiroshi Ichikawa, 2017/06/01 01:20:37]

Done. I also extracted -toggleIncognito as a method because it became longer.

+  return _isIncognito ? [CWVWebViewConfiguration incognitoConfiguration]
+                      : [CWVWebViewConfiguration defaultConfiguration];
+}
+
+- (void)createWebViewWithConfiguration:(CWVWebViewConfiguration*)configuration {
+  self.webView = [[CWVWebView alloc] initWithFrame:[_containerView bounds]
+                                     configuration:configuration];
+  // Gives a restoration identifier so that state restoration works.
+  _webView.restorationIdentifier = @"webView";
+  _webView.navigationDelegate = self;
+  _webView.UIDelegate = self;
+  _translationDelegate = [[ShellTranslationDelegate alloc] init];
+  _webView.translationController.delegate = _translationDelegate;
+
+  [_webView setAutoresizingMask:UIViewAutoresizingFlexibleWidth |
+                                UIViewAutoresizingFlexibleHeight];
+  [_containerView addSubview:_webView];
+
+  [_webView addObserver:self
+             forKeyPath:@"canGoBack"
+                options:NSKeyValueObservingOptionNew
+                context:nil];
+  [_webView addObserver:self
+             forKeyPath:@"canGoForward"
+                options:NSKeyValueObservingOptionNew
+                context:nil];
+
+  NSURLRequest* request = [NSURLRequest
+      requestWithURL:[NSURL URLWithString:@"https://www.google.com/"]];
+  [_webView loadRequest:request];
+}
+
+- (void)removeWebView {
   [_webView removeFromSuperview];
   [_webView removeObserver:self forKeyPath:@"canGoBack"];
   [_webView removeObserver:self forKeyPath:@"canGoForward"];