Added support for command-line switch to select individual examples.

Hide the example combo-box selector if there is only one example to show.

Part of Views Documentation effort.

Change-Id: I9019148e54d7162bfb8b95a88c515504f130e7d1
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2153307
Commit-Queue: Allen Bauer <kylixrd@chromium.org>
Reviewed-by: Xiyuan Xia <xiyuan@chromium.org>
Reviewed-by: Peter Kasting <pkasting@chromium.org>
Cr-Commit-Position: refs/heads/master@{#760990}

ui/views/examples/combobox_example.cc

@@ -41,20 +41,19 @@ ComboboxExample::ComboboxExample() : ExampleBase("Combo Box") {}
 ComboboxExample::~ComboboxExample() = default;
 
 void ComboboxExample::CreateExampleView(View* container) {
-  combobox_ = new Combobox(std::make_unique<ComboboxModelExample>());
+  container->SetLayoutManager(std::make_unique<BoxLayout>(
+      BoxLayout::Orientation::kVertical, gfx::Insets(10, 0), 5));
+
+  combobox_ = container->AddChildView(
+      std::make_unique<Combobox>(std::make_unique<ComboboxModelExample>()));
   combobox_->set_listener(this);
   combobox_->SetSelectedIndex(3);
 
-  auto* disabled_combobox =
-      new Combobox(std::make_unique<ComboboxModelExample>());
+  auto* disabled_combobox = container->AddChildView(
+      std::make_unique<Combobox>(std::make_unique<ComboboxModelExample>()));
   disabled_combobox->set_listener(this);
   disabled_combobox->SetSelectedIndex(4);
   disabled_combobox->SetEnabled(false);
-
-  container->SetLayoutManager(std::make_unique<BoxLayout>(
-      BoxLayout::Orientation::kVertical, gfx::Insets(10, 0), 5));
-  container->AddChildView(combobox_);
-  container->AddChildView(disabled_combobox);
 }
 
 void ComboboxExample::OnPerformAction(Combobox* combobox) {

ui/views/examples/create_examples.cc

@@ -39,8 +39,8 @@ namespace views {
 namespace examples {
 
 // Creates the default set of examples.
-ExampleVector CreateExamples() {
-  ExampleVector examples;
+ExampleVector CreateExamples(ExampleVector extra_examples) {
+  ExampleVector examples = std::move(extra_examples);
   examples.push_back(std::make_unique<AxExample>());
   examples.push_back(std::make_unique<BoxLayoutExample>());
   examples.push_back(std::make_unique<BubbleExample>());

ui/views/examples/create_examples.h

@@ -14,10 +14,9 @@
 namespace views {
 namespace examples {
 
-using ExampleVector = std::vector<std::unique_ptr<ExampleBase>>;
-
 // Creates the default set of examples.
-ExampleVector VIEWS_EXAMPLES_EXPORT CreateExamples();
+ExampleVector VIEWS_EXAMPLES_EXPORT
+CreateExamples(ExampleVector extra_examples = ExampleVector());
 
 }  // namespace examples
 }  // namespace views

ui/views/examples/example_base.h

@@ -6,6 +6,7 @@
 #define UI_VIEWS_EXAMPLES_EXAMPLE_BASE_H_
 
 #include <string>
+#include <vector>
 
 #include "base/macros.h"
 #include "ui/views/examples/views_examples_export.h"
@@ -38,6 +39,8 @@ class VIEWS_EXAMPLES_EXPORT ExampleBase {
   DISALLOW_COPY_AND_ASSIGN(ExampleBase);
 };
 
+using ExampleVector = std::vector<std::unique_ptr<ExampleBase>>;
+
 }  // namespace examples
 }  // namespace views
 

ui/views/examples/examples_window.cc

@@ -10,8 +10,11 @@
 #include <string>
 #include <utility>
 
+#include "base/command_line.h"
 #include "base/macros.h"
 #include "base/run_loop.h"
+#include "base/stl_util.h"
+#include "base/strings/string_split.h"
 #include "base/strings/utf_string_conversions.h"
 #include "ui/base/l10n/l10n_util.h"
 #include "ui/base/models/combobox_model.h"
@@ -29,21 +32,47 @@
 namespace views {
 namespace examples {
 
-using ExampleVector = std::vector<std::unique_ptr<ExampleBase>>;
-
 namespace {
 
-struct ExampleTitleCompare {
-  bool operator()(const std::unique_ptr<ExampleBase>& a,
-                  const std::unique_ptr<ExampleBase>& b) {
+const char kEnableExamples[] = "enable-examples";
+
+ExampleVector GetExamplesToShow(ExampleVector examples) {
+  using StringVector = std::vector<std::string>;
+  base::CommandLine* command_line = base::CommandLine::ForCurrentProcess();
+
+  std::sort(examples.begin(), examples.end(), [](const auto& a, const auto& b) {
     return a->example_title() < b->example_title();
+  });
+
+  std::string enable_examples =
+      command_line->GetSwitchValueASCII(kEnableExamples);
+  if (!enable_examples.empty()) {
+    StringVector enabled =
+        base::SplitString(enable_examples, ";,", base::TRIM_WHITESPACE,
+                          base::SPLIT_WANT_NONEMPTY);
+
+    // Transform list of examples to just the list of names.
+    StringVector example_names;
+    std::transform(
+        examples.begin(), examples.end(), std::back_inserter(example_names),
+        [](const auto& example) { return example->example_title(); });
+
+    std::sort(enabled.begin(), enabled.end());
+
+    // Get an intersection of list of titles between the full list and the list
+    // from the command-line.
+    StringVector valid_examples =
+        base::STLSetIntersection<StringVector>(enabled, example_names);
+
+    // If there are still example names in the list, only include the examples
+    // from the list.
+    if (!valid_examples.empty()) {
+      base::EraseIf(examples, [valid_examples](auto& example) {
+        return std::find(valid_examples.begin(), valid_examples.end(),
+                         example->example_title()) == valid_examples.end();
+      });
+    }
   }
-};
-
-ExampleVector GetExamplesToShow(ExampleVector extra) {
-  ExampleVector examples = CreateExamples();
-  std::move(extra.begin(), extra.end(), std::back_inserter(examples));
-  std::sort(examples.begin(), examples.end(), ExampleTitleCompare());
 
   for (auto& example : examples)
     example->CreateExampleView(example->example_view());
@@ -104,7 +133,9 @@ class ExamplesWindowContents : public WidgetDelegateView,
     layout->StartRow(0 /* no expand */, 0);
     combobox_ = layout->AddView(std::move(combobox));
 
-    if (combobox_model_->GetItemCount() > 0) {
+    auto item_count = combobox_model_->GetItemCount();
+    if (item_count > 0) {
+      combobox_->SetVisible(item_count > 1);
       layout->StartRow(1, 0);
       auto example_shown = std::make_unique<View>();
       example_shown->SetLayoutManager(std::make_unique<FillLayout>());
@@ -176,12 +207,12 @@ class ExamplesWindowContents : public WidgetDelegateView,
 ExamplesWindowContents* ExamplesWindowContents::instance_ = nullptr;
 
 void ShowExamplesWindow(base::OnceClosure on_close,
-                        gfx::NativeWindow window_context,
-                        ExampleVector extra_examples) {
+                        ExampleVector examples,
+                        gfx::NativeWindow window_context) {
   if (ExamplesWindowContents::instance()) {
     ExamplesWindowContents::instance()->GetWidget()->Activate();
   } else {
-    ExampleVector examples = GetExamplesToShow(std::move(extra_examples));
+    examples = GetExamplesToShow(std::move(examples));
     Widget* widget = new Widget;
     Widget::InitParams params;
     params.delegate =

ui/views/examples/examples_window.h

@@ -11,21 +11,20 @@
 
 #include "base/strings/stringprintf.h"
 #include "ui/gfx/native_widget_types.h"
+#include "ui/views/examples/create_examples.h"
+#include "ui/views/examples/example_base.h"
 #include "ui/views/examples/views_examples_export.h"
 
 namespace views {
 namespace examples {
 
-class VIEWS_EXAMPLES_EXPORT ExampleBase;
-
 // Shows a window with the views examples in it. |extra_examples| contains any
 // additional examples to add. |window_context| is used to determine where the
 // window should be created (see |Widget::InitParams::context| for details).
 VIEWS_EXAMPLES_EXPORT void ShowExamplesWindow(
     base::OnceClosure on_close,
-    gfx::NativeWindow window_context = nullptr,
-    std::vector<std::unique_ptr<ExampleBase>> extra_examples =
-        std::vector<std::unique_ptr<ExampleBase>>());
+    ExampleVector examples = CreateExamples(),
+    gfx::NativeWindow window_context = nullptr);
 
 // Prints |string| in the status area, at the bottom of the window.
 VIEWS_EXAMPLES_EXPORT void LogStatus(const std::string& string);

ui/views/examples/examples_window_with_content.cc

@@ -9,6 +9,8 @@
 #include <vector>
 
 #include "content/public/browser/browser_context.h"
+#include "ui/views/examples/create_examples.h"
+#include "ui/views/examples/example_base.h"
 #include "ui/views/examples/webview_example.h"
 
 namespace views {
@@ -17,10 +19,10 @@ namespace examples {
 void ShowExamplesWindowWithContent(base::OnceClosure on_close,
                                    content::BrowserContext* browser_context,
                                    gfx::NativeWindow window_context) {
-  std::vector<std::unique_ptr<ExampleBase>> extra_examples;
-  extra_examples.push_back(std::make_unique<WebViewExample>(browser_context));
-  ShowExamplesWindow(std::move(on_close), window_context,
-                     std::move(extra_examples));
+  ExampleVector examples;
+  examples.push_back(std::make_unique<WebViewExample>(browser_context));
+  ShowExamplesWindow(std::move(on_close), CreateExamples(std::move(examples)),
+                     window_context);
 }
 
 }  // namespace examples