diff --git a/atom/browser/api/atom_api_box_layout.cc b/atom/browser/api/atom_api_box_layout.cc
index b37430b6eb0..99e2efc55b7 100644
--- a/atom/browser/api/atom_api_box_layout.cc
+++ b/atom/browser/api/atom_api_box_layout.cc
@@ -6,6 +6,7 @@
 
 #include <string>
 
+#include "atom/browser/api/atom_api_view.h"
 #include "atom/common/api/constructor.h"
 #include "native_mate/dictionary.h"
 
@@ -42,6 +43,11 @@ BoxLayout::BoxLayout(views::BoxLayout::Orientation orientation)
 
 BoxLayout::~BoxLayout() {}
 
+void BoxLayout::SetFlexForView(mate::Handle<View> view, int flex) {
+  auto* box_layout = static_cast<views::BoxLayout*>(layout_manager());
+  box_layout->SetFlexForView(view->view(), flex);
+}
+
 // static
 mate::WrappableBase* BoxLayout::New(mate::Arguments* args,
                                     views::BoxLayout::Orientation orientation) {
@@ -52,7 +58,11 @@ mate::WrappableBase* BoxLayout::New(mate::Arguments* args,
 
 // static
 void BoxLayout::BuildPrototype(v8::Isolate* isolate,
-                               v8::Local<v8::FunctionTemplate> prototype) {}
+                               v8::Local<v8::FunctionTemplate> prototype) {
+  prototype->SetClassName(mate::StringToV8(isolate, "BoxLayout"));
+  mate::ObjectTemplateBuilder(isolate, prototype->PrototypeTemplate())
+      .SetMethod("setFlexForView", &BoxLayout::SetFlexForView);
+}
 
 }  // namespace api
 
diff --git a/atom/browser/api/atom_api_box_layout.h b/atom/browser/api/atom_api_box_layout.h
index 804cc244c1d..b29e2eda6ab 100644
--- a/atom/browser/api/atom_api_box_layout.h
+++ b/atom/browser/api/atom_api_box_layout.h
@@ -6,12 +6,15 @@
 #define ATOM_BROWSER_API_ATOM_API_BOX_LAYOUT_H_
 
 #include "atom/browser/api/atom_api_layout_manager.h"
+#include "native_mate/handle.h"
 #include "ui/views/layout/box_layout.h"
 
 namespace atom {
 
 namespace api {
 
+class View;
+
 class BoxLayout : public LayoutManager {
  public:
   static mate::WrappableBase* New(mate::Arguments* args,
@@ -20,6 +23,8 @@ class BoxLayout : public LayoutManager {
   static void BuildPrototype(v8::Isolate* isolate,
                              v8::Local<v8::FunctionTemplate> prototype);
 
+  void SetFlexForView(mate::Handle<View> view, int flex);
+
  protected:
   explicit BoxLayout(views::BoxLayout::Orientation orientation);
   ~BoxLayout() override;
diff --git a/atom/browser/api/atom_api_view.cc b/atom/browser/api/atom_api_view.cc
index 650ad18cdec..a79e6fa689d 100644
--- a/atom/browser/api/atom_api_view.cc
+++ b/atom/browser/api/atom_api_view.cc
@@ -30,6 +30,18 @@ void View::SetLayoutManager(mate::Handle<LayoutManager> layout_manager) {
   view()->SetLayoutManager(layout_manager->TakeOver().release());
 }
 
+void View::AddChildView(mate::Handle<View> child) {
+  AddChildViewAt(child, child_views_.size());
+}
+
+void View::AddChildViewAt(mate::Handle<View> child, size_t index) {
+  if (index > child_views_.size())
+    return;
+  child_views_.emplace(child_views_.begin() + index,     // index
+                       isolate(), child->GetWrapper());  // v8::Global(args...)
+  view()->AddChildViewAt(child->view(), index);
+}
+
 // static
 mate::WrappableBase* View::New(mate::Arguments* args) {
   auto* view = new View();
@@ -42,7 +54,9 @@ void View::BuildPrototype(v8::Isolate* isolate,
                           v8::Local<v8::FunctionTemplate> prototype) {
   prototype->SetClassName(mate::StringToV8(isolate, "View"));
   mate::ObjectTemplateBuilder(isolate, prototype->PrototypeTemplate())
-      .SetMethod("setLayoutManager", &View::SetLayoutManager);
+      .SetMethod("setLayoutManager", &View::SetLayoutManager)
+      .SetMethod("addChildView", &View::AddChildView)
+      .SetMethod("addChildViewAt", &View::AddChildViewAt);
 }
 
 }  // namespace api
diff --git a/atom/browser/api/atom_api_view.h b/atom/browser/api/atom_api_view.h
index 37f7ae4e1c7..80f17e61416 100644
--- a/atom/browser/api/atom_api_view.h
+++ b/atom/browser/api/atom_api_view.h
@@ -6,6 +6,7 @@
 #define ATOM_BROWSER_API_ATOM_API_VIEW_H_
 
 #include <memory>
+#include <vector>
 
 #include "atom/browser/api/atom_api_layout_manager.h"
 #include "native_mate/handle.h"
@@ -23,6 +24,8 @@ class View : public mate::TrackableObject<View> {
                              v8::Local<v8::FunctionTemplate> prototype);
 
   void SetLayoutManager(mate::Handle<LayoutManager> layout_manager);
+  void AddChildView(mate::Handle<View> view);
+  void AddChildViewAt(mate::Handle<View> view, size_t index);
 
   views::View* view() const { return view_; }
 
@@ -36,6 +39,7 @@ class View : public mate::TrackableObject<View> {
 
  private:
   v8::Global<v8::Object> layout_manager_;
+  std::vector<v8::Global<v8::Object>> child_views_;
 
   bool delete_view_ = true;
   views::View* view_ = nullptr;
diff --git a/atom/browser/ui/cocoa/delayed_native_view_host.cc b/atom/browser/ui/cocoa/delayed_native_view_host.cc
index 0d48668895d..95d369bfd82 100644
--- a/atom/browser/ui/cocoa/delayed_native_view_host.cc
+++ b/atom/browser/ui/cocoa/delayed_native_view_host.cc
@@ -14,7 +14,7 @@ DelayedNativeViewHost::~DelayedNativeViewHost() {}
 void DelayedNativeViewHost::ViewHierarchyChanged(
     const ViewHierarchyChangedDetails& details) {
   NativeViewHost::ViewHierarchyChanged(details);
-  if (details.is_add)
+  if (details.is_add && GetWidget())
     Attach(native_view_);
 }