Handle invalid URLs in share extension.

ios/chrome/share_extension/share_view_controller.mm

 // Copyright 2016 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.
 
 #import <MobileCoreServices/MobileCoreServices.h>
 
 #import "ios/chrome/share_extension/share_view_controller.h"
 
 #import "base/ios/block_types.h"
 #import "base/mac/foundation_util.h"
@@ skipping 22 matching lines @@
 
 }  // namespace
 
 @interface ShareViewController ()<ShareExtensionViewActionTarget> {
   // This constraint the center of the widget to be vertically in the center
   // of the the screen. It has to be modified for the dismissal animation.
   NSLayoutConstraint* _centerYConstraint;
 
   NSURL* _shareURL;
   NSString* _shareTitle;
+  UIImage* _image;
   NSExtensionItem* _shareItem;
 }
 
 @property(nonatomic, weak) UIView* maskView;
 @property(nonatomic, weak) ShareExtensionView* shareView;
 @property(nonatomic, assign) app_group::ShareExtensionItemType itemType;
 
 // Creates a files in |app_group::ShareExtensionItemsFolder()| containing a
 // serialized NSDictionary.
 // If |cancel| is true, |actionType| is ignored.
 - (void)queueActionItemURL:(NSURL*)URL
                      title:(NSString*)title
                     action:(app_group::ShareExtensionItemType)actionType
                     cancel:(BOOL)cancel
                 completion:(ProceduralBlock)completion;
 
 // Loads all the shared elements from the extension context and update the UI.
 - (void)loadElementsFromContext;
 
 // Sets constaints to the widget so that margin are at least
 // kShareExtensionMargin points and widget width is closest up to
 // kShareExtensionMaxWidth points.
 - (void)constrainWidgetWidth;
 
+// Display the normal share view.

[gambard, 2017/01/02 09:11:41]

s/Display/Displays

[Olivier, 2017/01/02 10:40:40]

Done.

+- (void)displayShareView;
+
+// Display an alert to report an error to the user.

[gambard, 2017/01/02 09:11:41]

s/Display/Displays

[Olivier, 2017/01/02 10:40:40]

Done.

+- (void)displayErrorView;
+
 @end
 
 @implementation ShareViewController
 
 @synthesize maskView = _maskView;
 @synthesize shareView = _shareView;
 @synthesize itemType = _itemType;
 
 #pragma mark - UIViewController
 
@@ skipping 14 matching lines @@
   [self setShareView:shareView];
   [self.view addSubview:self.shareView];
 
   [self constrainWidgetWidth];
 
   // Position the widget below the screen. It will be slided up with an
   // animation.
   _centerYConstraint = [[shareView centerYAnchor]
       constraintEqualToAnchor:[self.view centerYAnchor]];
   [_centerYConstraint setConstant:(self.view.frame.size.height +
-                                   self.shareView.frame.size.height) /
-                                  2];

[gambard, 2017/01/02 09:11:41]

Why removing the /2?

[Olivier, 2017/01/02 10:40:40]

In view did load, the size of Shareview is not final.
It can change if text or image is added as this is asynchronous.
It was fine as animation started immediately, but now that we can have errors,
the widget could be visible at the bottom.

Changing the constraint to be closer to the actual intended behavior

+                                   self.shareView.frame.size.height)];
   [_centerYConstraint setActive:YES];
   [[[shareView centerXAnchor] constraintEqualToAnchor:[self.view centerXAnchor]]
       setActive:YES];
 
   [self.maskView setTranslatesAutoresizingMaskIntoConstraints:NO];
   [self.shareView setTranslatesAutoresizingMaskIntoConstraints:NO];
 
   [self loadElementsFromContext];
 }
 
-- (void)viewWillAppear:(BOOL)animated {
-  [super viewWillAppear:animated];
-
-  // Center the widget.
-  [_centerYConstraint setConstant:0];
-  [self.maskView setAlpha:0];
-  [UIView animateWithDuration:kAnimationDuration
-                   animations:^{
-                     [self.maskView setAlpha:1];
-                     [self.view layoutIfNeeded];
-                   }];
-}
-
 #pragma mark - Private methods
 
+- (void)displayShareView {
+  [self.shareView setTitle:_shareTitle];
+  [self.shareView setURL:_shareURL];
+  if (_image) {
+    [self.shareView setScreenshot:_image];
+  }
+  dispatch_async(dispatch_get_main_queue(), ^{
+    // Center the widget.
+    [_centerYConstraint setConstant:0];
+    [self.maskView setAlpha:0];
+    [UIView animateWithDuration:kAnimationDuration
+                     animations:^{
+                       [self.maskView setAlpha:1];
+                       [self.view layoutIfNeeded];
+                     }];
+  });
+}
+
+- (void)displayErrorView {
+  NSString* errorMessage =
+      NSLocalizedString(@"IDS_IOS_ERROR_MESSAGE_SHARE_EXTENSION",
+                        @"The error message to display to the user.");
+  NSString* okButton =
+      NSLocalizedString(@"IDS_IOS_OK_BUTTON_SHARE_EXTENSION",
+                        @"The label of the OK button in share extension.");
+  NSString* applicationName = [[[NSBundle mainBundle] infoDictionary]
+      valueForKey:@"CFBundleDisplayName"];
+  errorMessage =
+      [errorMessage stringByReplacingOccurrencesOfString:@"APPLICATION_NAME"
+                                              withString:applicationName];
+  UIAlertController* alert =
+      [UIAlertController alertControllerWithTitle:errorMessage
+                                          message:[_shareURL absoluteString]
+                                   preferredStyle:UIAlertControllerStyleAlert];
+  UIAlertAction* defaultAction =
+      [UIAlertAction actionWithTitle:okButton
+                               style:UIAlertActionStyleDefault
+                             handler:^(UIAlertAction* action) {
+                               [self dismissAndReturnItem:nil];
+                             }];
+  [alert addAction:defaultAction];
+  [self presentViewController:alert animated:YES completion:nil];
+}
+
 - (void)constrainWidgetWidth {
   // Setting the constraints.
   NSDictionary* views = @{ @"share" : self.shareView };
 
   NSDictionary* metrics = @{
     @"margin" : @(kShareExtensionMargin),
     @"maxWidth" : @(kShareExtensionMaxWidth),
   };
 
   NSArray* constraints = @[
@@ skipping 26 matching lines @@
       if ([itemProvider hasItemConformingToTypeIdentifier:typeURL]) {
         ItemBlock URLCompletion = ^(id idURL, NSError* error) {
           NSURL* URL = static_cast<NSURL*>(idURL);
           dispatch_async(dispatch_get_main_queue(), ^{
             _shareItem = [item copy];
             _shareURL = [URL copy];
             _shareTitle = [[[item attributedContentText] string] copy];
             if ([_shareTitle length] == 0) {
               _shareTitle = [URL host];
             }
-            [self.shareView setURL:URL];
-            [self.shareView setTitle:_shareTitle];
+            if ([[_shareURL scheme] isEqualToString:@"http"] ||
+                [[_shareURL scheme] isEqualToString:@"https"]) {
+              [self displayShareView];
+            } else {
+              [self displayErrorView];
+            }
           });
 
         };
         [itemProvider loadItemForTypeIdentifier:typeURL
                                         options:nil
                               completionHandler:URLCompletion];
         NSDictionary* imageOptions = @{
           NSItemProviderPreferredImageSizeKey : [NSValue
               valueWithCGSize:CGSizeMake(kScreenShotWidth, kScreenShotHeight)]
         };
-        ItemBlock ImageCompletion = ^(id item, NSError* error) {
-
-          UIImage* image = static_cast<UIImage*>(item);
-          if (image) {
+        ItemBlock imageCompletion = ^(id item, NSError* error) {
+          _image = static_cast<UIImage*>(item);
+          if (_image && self.shareView) {
             dispatch_async(dispatch_get_main_queue(), ^{
-              [self.shareView setScreenshot:image];
+              [self.shareView setScreenshot:_image];
             });
           }
 
         };
         [itemProvider loadPreviewImageWithOptions:imageOptions
-                                completionHandler:ImageCompletion];
+                                completionHandler:imageCompletion];
       }
     }
   }
 }
 
 - (void)dismissAndReturnItem:(NSExtensionItem*)item {
   // Set the Y center constraints so the whole extension slides out of the
   // screen. Constant is relative to the center of the screen.
   // The direction (up or down) is relative to the output (cancel or submit).
   NSInteger direction = item ? -1 : 1;
@@ skipping 90 matching lines @@
                   [self dismissAndReturnItem:_shareItem];
                 }];
 }
 
 - (void)shareExtensionView:(id)sender
                typeChanged:(app_group::ShareExtensionItemType)type {
   [self setItemType:type];
 }
 
 @end