adds Dropdown elements

- DropdownButton
- SplitButton
- Dropdown (Toggle, Menu, Item, Header, Divider)

Author: matdsoupe

src/ReactBootstrap.res

@@ -387,7 +387,7 @@ module Carousel = {
     ~keyboard: bool=?,
     ~nextIcon: reactNode=?,
     ~nextLabel: string=?,
-    ~onSelect: (~eventKey: int, ~event: option<ReactEvent.Form.t>) => unit,
+    ~onSelect: (~eventKey: int, ~event: option<ReactEvent.Selection.t>) => unit,
     ~onSlid: (~eventKey: int, ~direction: [#start | #end]) => unit,
     ~onSlide: (~eventKey: int, ~direction: [#start | #end]) => unit,
     ~pause: [#hover],
@@ -435,6 +435,140 @@ module CloseButton = {
   ) => React.element = "CloseButton"
 }
 
+module DropdownButton = {
+  @module("react-bootstrap") @react.component
+  external make: (
+    ~align: [#start | #end]=?,
+    ~disabled: bool=?,
+    ~href: string=?,
+    ~id: string=?,
+    ~menuRole: string=?,
+    ~menuVariant: [#dark]=?,
+    ~onClick: ReactEvent.Form.t => unit=?,
+    ~renderMenuOnMount: bool=?,
+    ~rootCloseEvent: string=?,
+    ~size: string=?,
+    ~title: string,
+    ~variant: variant=?,
+    ~className: string=?,
+    ~children: React.element,
+    ~bsPrefix: string=?,
+  ) => React.element = "DropdownButton"
+}
+
+module SplitButton = {
+  @module("react-bootstrap") @react.component
+  external make: (
+    ~align: [#start | #end]=?,
+    ~disabled: bool=?,
+    ~href: string=?,
+    ~id: string,
+    ~menuRole: string=?,
+    ~onClick: ReactEvent.Form.t => unit=?,
+    ~rootCloseEvent: string=?,
+    ~size: size=?,
+    ~target: string=?,
+    ~title: string,
+    ~toggleLabel: string=?,
+    ~_type: string=?,
+    ~variant: variant=?,
+    ~className: string=?,
+    ~children: React.element,
+    ~bsPrefix: string=?,
+  ) => React.element = "SplitButton"
+}
+
+module Dropdown = {
+  type autoClose = Bool(bool) | Side([#outside | #inside])
+  type drop = [#up | #start | #end | #down]
+  type focus = Bool(bool) | Keyboard([#keyboard])
+
+  type toggleMetadata = {source: [#select | #click | #rootClose | #keydown]}
+
+  @module("react-bootstrap") @react.component
+  external make: (
+    ~align: [#start | #end]=?,
+    ~_as: string=?,
+    ~autoClose: autoClose=?,
+    ~drop: drop=?,
+    ~flip: bool=?,
+    ~focusFirstItemOnShow: focus=?,
+    ~navbar: bool=?,
+    ~onSelect: (~eventKey: string, ~event: ReactEvent.Selection.t) => unit=?,
+    ~onToggle: (~isOpen: bool, ~event: ReactEvent.Synthetic.t, ~metadata: toggleMetadata) => unit=?,
+    ~show: bool=?,
+    ~className: string=?,
+    ~children: React.element,
+    ~bsPrefix: string=?,
+  ) => React.element = "Dropdown"
+
+  module Toggle = {
+    @module("react-bootstrap") @scope("Dropdown") @react.component
+    external make: (
+      ~_as: string=?,
+      ~childBsPrefix: string=?,
+      ~id: string=?,
+      ~split: bool=?,
+      ~className: string=?,
+      ~children: React.element,
+      ~bsPrefix: string=?,
+    ) => React.element = "Toggle"
+  }
+
+  module Menu = {
+    @module("react-bootstrap") @scope("Dropdown") @react.component
+    external make: (
+      ~align: [#start | #end]=?,
+      ~_as: string=?,
+      ~flip: bool=?,
+      ~onSelect: (~eventKey: string, ~event: ReactEvent.Selection.t) => unit=?,
+      ~popperConfig: {.}=?,
+      ~renderOnMount: bool=?,
+      ~rootCloseEvent: [#click | #mousedown]=?,
+      ~show: bool=?,
+      ~variant: variant=?,
+      ~className: string=?,
+      ~children: React.element,
+      ~bsPrefix: string=?,
+    ) => React.element = "Menu"
+  }
+
+  module Item = {
+    @module("react-bootstrap") @scope("Dropdown") @react.component
+    external make: (
+      ~active: bool=?,
+      ~_as: string=?,
+      ~disabled: bool=?,
+      ~eventKey: string=?,
+      ~href: string=?,
+      ~onClick: ReactEvent.Mouse.t,
+      ~className: string=?,
+      ~children: React.element,
+      ~bsPrefix: string=?,
+    ) => React.element = "Item"
+  }
+
+  module Header = {
+    @module("react-bootstrap") @scope("Dropdown") @react.component
+    external make: (
+      ~_as: string=?,
+      ~className: string=?,
+      ~children: React.element,
+      ~bsPrefix: string,
+    ) => React.element = "Header"
+  }
+
+  module Divider = {
+    @module("react-bootstrap") @scope("Dropdown") @react.component
+    external make: (
+      ~_as: string=?,
+      ~className: string=?,
+      ~children: React.element,
+      ~bsPrefix: string,
+    ) => React.element = "Divider"
+  }
+}
+
 module Container = {
   @module("react-bootstrap") @react.component
   external make: (~children: React.element, ~className: string=?) => React.element = "Container"