Picker takes a vector of pairs, and passes back the user chosen target.

chrome/browser/ui/views/webshare/webshare_target_picker_view.cc

 // 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.
 
 #include "chrome/browser/ui/views/webshare/webshare_target_picker_view.h"
 
 #include "chrome/grit/generated_resources.h"
 #include "components/constrained_window/constrained_window_views.h"
 #include "ui/base/l10n/l10n_util.h"
 #include "ui/gfx/native_widget_types.h"
 #include "ui/views/controls/label.h"
-#include "ui/views/controls/table/table_view.h"
 #include "ui/views/layout/box_layout.h"
 #include "ui/views/layout/layout_constants.h"
 
 namespace {
 
 int kDialogWidth = 500;
 int kDialogHeight = 400;
 
 }  // namespace
 
 namespace chrome {
 
 void ShowWebShareTargetPickerDialog(
     gfx::NativeWindow parent_window,
     const std::vector<base::string16>& targets,
-    const base::Callback<void(SharePickerResult)>& callback) {
+    const base::Callback<void(base::Optional<base::string16>)>& callback) {
   constrained_window::CreateBrowserModalDialogViews(
       new WebShareTargetPickerView(targets, callback), parent_window)
       ->Show();
 }
 
 }  // namespace chrome
 
 WebShareTargetPickerView::WebShareTargetPickerView(
     const std::vector<base::string16>& targets,
-    const base::Callback<void(SharePickerResult)>& close_callback)
+    const base::Callback<void(base::Optional<base::string16>)>& close_callback)
     : targets_(targets), close_callback_(close_callback) {
   views::BoxLayout* layout = new views::BoxLayout(
       views::BoxLayout::kVertical, views::kPanelHorizMargin,
       views::kPanelVertMargin, views::kRelatedControlVerticalSpacing);
   SetLayoutManager(layout);
 
   views::Label* overview_label = new views::Label(
       l10n_util::GetStringUTF16(IDS_WEBSHARE_TARGET_PICKER_LABEL));
   AddChildView(overview_label);
 
   std::vector<ui::TableColumn> table_columns{ui::TableColumn()};
-  views::TableView* table =
-      new views::TableView(this, table_columns, views::TEXT_ONLY, true);
+  table_ = new views::TableView(this, table_columns, views::TEXT_ONLY, true);
   // Select the first row.
   if (RowCount() > 0)
-    table->Select(0);
+    table_->Select(0);
 
   // Create the table parent (a ScrollView which includes the scroll bars and
   // border). We add this parent (not the table itself) to the dialog.
-  views::View* table_parent = table->CreateParentIfNecessary();
+  views::View* table_parent = table_->CreateParentIfNecessary();
   AddChildView(table_parent);
   // Make the table expand to fill the space.
   layout->SetFlexForView(table_parent, 1);
 }
 
 WebShareTargetPickerView::~WebShareTargetPickerView() {}
 
 gfx::Size WebShareTargetPickerView::GetPreferredSize() const {
   return gfx::Size(kDialogWidth, kDialogHeight);
 }
 
 ui::ModalType WebShareTargetPickerView::GetModalType() const {
   return ui::MODAL_TYPE_WINDOW;
 }
 
 base::string16 WebShareTargetPickerView::GetWindowTitle() const {
   return l10n_util::GetStringUTF16(IDS_WEBSHARE_TARGET_PICKER_TITLE);
 }
 
 bool WebShareTargetPickerView::Cancel() {
   if (!close_callback_.is_null())
-    close_callback_.Run(SharePickerResult::CANCEL);
+    close_callback_.Run(base::nullopt);
 
   return true;
 }
 
 bool WebShareTargetPickerView::Accept() {
   if (!close_callback_.is_null())
-    close_callback_.Run(SharePickerResult::SHARE);
+    close_callback_.Run(GetText(table_->FirstSelectedRow(), 0));

[sky, 2017/01/31 05:22:32]

What if there is no selected row?

[constantina, 2017/01/31 23:29:42]

If there are no targets in the list, there will be no selected row, but for now,
there is always a selected row, as there is always at least one target. (The
first row is selected by default.)

[Matt Giuca, 2017/01/31 23:48:27]

This is true now, but won't be true very soon (and this file shouldn't assume
there will always be at least one row, because it isn't enforcing it). Please
add a check for this case.

[sky, 2017/02/01 00:51:33]

Not just that, but there is nothing stopping the user from clearing the
selection.

[constantina, 2017/02/01 01:06:02]

Done. If nothing is selected and user accepts, UI behaves as though share was
cancelled.

 
   return true;
 }
 
 base::string16 WebShareTargetPickerView::GetDialogButtonLabel(
     ui::DialogButton button) const {
   if (button == ui::DIALOG_BUTTON_OK)
     return l10n_util::GetStringUTF16(IDS_WEBSHARE_TARGET_PICKER_COMMIT);
 
   return views::DialogDelegateView::GetDialogButtonLabel(button);
 }
 
 int WebShareTargetPickerView::RowCount() {
   return targets_.size();
 }
 
 base::string16 WebShareTargetPickerView::GetText(int row, int /*column_id*/) {
   return targets_[row];
 }
 
 void WebShareTargetPickerView::SetObserver(ui::TableModelObserver* observer) {}