[Payment Request] Country selection coordinator

ios/chrome/browser/ui/payments/country_selection_coordinator.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.
+
+#import "ios/chrome/browser/ui/payments/country_selection_coordinator.h"
+
+#include "base/strings/sys_string_conversions.h"
+#import "ios/chrome/browser/ui/payments/payment_request_picker_row.h"
+#include "ios/chrome/browser/ui/payments/payment_request_picker_view_controller.h"
+#include "ios/chrome/grit/ios_strings.h"
+#include "ui/base/l10n/l10n_util.h"
+
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
+namespace {
+// The delay in nano seconds before notifying the delegate of the selection.

[macourteau, 2017/05/19 20:20:43]

nit: please elaborate on why this delay is needed here

[Moe, 2017/05/19 22:19:14]

Done.

+const int64_t kDelegateNotificationDelayInNanoSeconds = 0.2 * NSEC_PER_SEC;
+}  // namespace
+
+@interface CountrySelectionCoordinator ()
+
+@property(nonatomic, strong) PaymentRequestPickerViewController* viewController;
+
+// Called when the user selects a country. The cell is checked, the UI is locked
+// so that the user can't interact with it, then the delegate is notified. The
+// delay is here to let the user get a visual feedback of the selection before
+// this view disappears.
+- (void)delayedNotifyDelegateOfSelection:(NSString*)countryCode;
+
+@end
+
+@implementation CountrySelectionCoordinator
+
+@synthesize delegate = _delegate;
+@synthesize countries = _countries;
+@synthesize selectedCountryCode = _selectedCountryCode;
+@synthesize viewController = _viewController;
+
+- (void)start {
+  // Create the rows to display in the view controller.
+  NSMutableArray<PickerRow*>* rows = [[NSMutableArray alloc] init];
+  __block PickerRow* selectedRow = nil;
+  [self.countries
+      enumerateKeysAndObjectsUsingBlock:^(NSString* countryCode,
+                                          NSString* countryName, BOOL* stop) {
+        PickerRow* row =
+            [[PickerRow alloc] initWithLabel:countryName value:countryCode];
+        [rows addObject:row];
+        if (self.selectedCountryCode == countryCode)
+          selectedRow = row;
+      }];
+  self.viewController =
+      [[PaymentRequestPickerViewController alloc] initWithRows:rows
+                                                      selected:selectedRow];
+  self.viewController.title = l10n_util::GetNSString(IDS_IOS_AUTOFILL_COUNTRY);
+  self.viewController.delegate = self;
+
+  DCHECK(self.baseViewController.navigationController);
+  [self.baseViewController.navigationController
+      pushViewController:self.viewController
+                animated:YES];
+}
+
+- (void)stop {
+  [self.viewController.navigationController popViewControllerAnimated:YES];
+  self.viewController = nil;
+}
+
+#pragma mark - PaymentRequestPickerViewControllerDelegate
+
+- (void)paymentRequestPickerViewController:
+            (PaymentRequestPickerViewController*)controller
+                              didSelectRow:(PickerRow*)row {
+  [self delayedNotifyDelegateOfSelection:row.value];
+}
+
+#pragma mark - Helper methods
+
+- (void)delayedNotifyDelegateOfSelection:(NSString*)countryCode {
+  self.viewController.view.userInteractionEnabled = NO;
+  __weak CountrySelectionCoordinator* weakSelf = self;
+  dispatch_after(
+      dispatch_time(DISPATCH_TIME_NOW, kDelegateNotificationDelayInNanoSeconds),
+      dispatch_get_main_queue(), ^{
+        weakSelf.viewController.view.userInteractionEnabled = YES;
+        [weakSelf.delegate countrySelectionCoordinator:weakSelf
+                              didSelectCountryWithCode:countryCode];
+      });
+}
+
+@end