App List: Refactor ContentsSwitcherView so it doesn't hard-code pages.

ui/app_list/views/contents_switcher_view.cc

Index: ui/app_list/views/contents_switcher_view.cc
diff --git a/ui/app_list/views/contents_switcher_view.cc b/ui/app_list/views/contents_switcher_view.cc
index 994a1fe5e44af71398c266ce9cde0d448097a50f..1d114aeb37c9193b7b158a6c25699058f36f681c 100644
--- a/ui/app_list/views/contents_switcher_view.cc
+++ b/ui/app_list/views/contents_switcher_view.cc
@@ -4,10 +4,8 @@
 
 #include "ui/app_list/views/contents_switcher_view.h"
 
-#include "grit/ui_resources.h"
 #include "ui/app_list/app_list_constants.h"
 #include "ui/app_list/views/contents_view.h"
-#include "ui/base/resource/resource_bundle.h"
 #include "ui/views/controls/button/custom_button.h"
 #include "ui/views/controls/button/image_button.h"
 #include "ui/views/layout/box_layout.h"
@@ -21,29 +19,29 @@ const int kButtonSpacing = 4;
 
 }  // namespace
 
-ContentsSwitcherView::ContentsSwitcherView(ContentsView* contents_view)
-    : contents_view_(contents_view), buttons_(new views::View) {
+ContentsSwitcherView::ContentsSwitcherView()
+    : contents_view_(NULL), buttons_(new views::View) {
   AddChildView(buttons_);
 
   buttons_->SetLayoutManager(new views::BoxLayout(
       views::BoxLayout::kHorizontal, 0, 0, kButtonSpacing));
-  // TODO(mgiuca): Dynamically generate these buttons from the subviews of
-  // |contents_view|.
-  AddSwitcherButton(
-      IDR_APP_LIST_SEARCH_ICON,
-      contents_view->GetPageIndexForNamedPage(ContentsView::NAMED_PAGE_START));
-  AddSwitcherButton(
-      IDR_APP_LIST_APPS_ICON,
-      contents_view->GetPageIndexForNamedPage(ContentsView::NAMED_PAGE_APPS));
 }
 
 ContentsSwitcherView::~ContentsSwitcherView() {}
 
+void ContentsSwitcherView::Init(ContentsView* contents_view) {
+  contents_view_ = contents_view;
+}
+
 void ContentsSwitcherView::AddSwitcherButton(int resource_id, int page_index) {
+  // Must not be NULL at this point, because it might trigger ButtonPressed().
+  DCHECK(contents_view_);
+
   views::ImageButton* button = new views::ImageButton(this);
-  button->SetImage(
-      views::CustomButton::STATE_NORMAL,
-      ui::ResourceBundle::GetSharedInstance().GetImageSkiaNamed(resource_id));
+  if (resource_id)

[calamity, 2014/06/18 05:22:29]

nit: Braces around multiline statement.

[Matt Giuca, 2014/06/18 06:47:02]

Done.

+    button->SetImage(
+        views::CustomButton::STATE_NORMAL,
+        ui::ResourceBundle::GetSharedInstance().GetImageSkiaNamed(resource_id));
   button->set_tag(page_index);
   buttons_->AddChildView(button);
 }