Update ios-guide-04.md

ios-guide-04.md

@@ -136,4 +136,123 @@ end
 
 ## Step 6 :
 
+* potion g screen navigation
+
+修改 app/screens/navigation_screen.rb
+```
+class NavigationScreen < PM::TableScreen
+
+  def on_load
+    rmq.stylesheet = NavigationScreenStylesheet
+  end
+
+  def table_data
+
+    [{
+      title: nil,
+      cells: [
+        { title: '' },
+        { title: sign_in_out_title ,
+          action: :sign_in_out_button,
+        },
+        { title: 'Sign Up',
+          action: :sign_up_button,
+        },
+        add_credit_card_menu
+      ]
+    }]
+  end
+
+  def add_credit_card_menu
+    if Auth.signed_in?
+      { title: "Add Credit Card", action: :add_credit_card_action }
+    end
+  end
+
+  def sign_in_out_title
+    if Auth.signed_in?
+      "Logout"
+    else
+      "Sign In"
+    end
+  end
+
+  def sign_in_out_button
+    if Auth.signed_in?
+      sign_out_button
+    else
+      sign_in_button
+    end
+  end
+
+  def sign_in_button
+    open SignInScreen.new(nav_bar: true)
+  end
+
+  def sign_up_button
+    open SignUpScreen.new(nav_bar: true)
+  end
+
+  def sign_out_button
+    Auth.sign_out do
+      app.delegate.open_authenticated_root
+    end
+  end
+
+  def add_credit_card_action
+    open AddCreditCardScreen.new(nav_bar: true)
+#    open PaymentViewController.new
+#    mp StripeConnection.connectionWithPublishableKey("pk_test_APfRAnKNxAO78IG481nvbXqq")
+  end
+
+
+  def swap_center_controller(screen_class)
+    # Just use screen_class if you don't need a navigation bar
+    app_delegate.menu.center_controller = screen_class
+  end
+
+
+  # You don't have to reapply styles to all UIViews, if you want to optimize, another way to do it
+  # is tag the views you need to restyle in your stylesheet, then only reapply the tagged views, like so:
+  #   def logo(st)
+  #     st.frame = {t: 10, w: 200, h: 96}
+  #     st.centered = :horizontal
+  #     st.image = image.resource('logo')
+  #     st.tag(:reapply_style)
+  #   end
+  #
+  # Then in will_animate_rotate
+  #   find(:reapply_style).reapply_styles#
+
+  # Remove the following if you're only using portrait
+  def will_animate_rotate(orientation, duration)
+    reapply_styles
+  end
+end
+
+```
+
+修改 app/stylesheets/navigation_screen_stylesheet.rb
+
+```
+class NavigationScreenStylesheet < ApplicationStylesheet
+  # Add your view stylesheets here. You can then override styles if needed,
+  # example: include FooStylesheet
+
+  def setup
+    # Add stylesheet specific setup stuff here.
+    # Add application specific setup stuff in application_stylesheet.rb
+  end
+
+  def root_view(st)
+    st.background_color = color.white
+  end
+
+end
+
+```
+
+
+## Step 7 :
+
 * rake