more dart:ui dartdocs

sky/engine/bindings/dart_ui.dart

@@ -2,6 +2,13 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+/// Built-in types and core primitives for a Flutter application.
+///
+/// This library exposes the lowest-level services that Flutter frameworks use
+/// to bootstrap applications, such as methods to obtain handles for the mojo
+/// IPC system, classes for driving the graphics and text layout and rendering
+/// subsystems, callbacks for integrating with the engine scheduler and the
+/// pointer input system, and functions for image decoding.
 library dart_ui;
 
 import 'dart:async';

sky/engine/core/dart/painting.dart

@@ -4,21 +4,36 @@
 
 part of dart_ui;
 
+/// Opaque handle to raw decoded image data (pixels).
+///
+/// To obtain an Image object, use the [decodeImageFromDataPipe] or
+/// [decodeImageFromList] functions.
+///
+/// To draw an Image, use one of the methods on the [Canvas] class, such as
+/// [drawImage].
 abstract class Image extends NativeFieldWrapperClass2 {
+  /// The number of image pixels along the image's horizontal axis.
   int get width native "Image_width";
+
+  /// The number of image pixels along the image's vertical axis.
   int get height native "Image_height";
 
+  /// Release the resources used by this object. The object is no longer usable
+  /// after this method is called.
   void dispose() native "Image_dispose";
 
   String toString() => '[$width\u00D7$height]';
 }
 
-typedef void _ImageDecoderCallback(Image result);
+/// Callback signature for [decodeImageFromDataPipe] and [decodeImageFromList].
+typedef void ImageDecoderCallback(Image result);
 
-void decodeImageFromDataPipe(int handle, _ImageDecoderCallback callback)
+/// Convert an image file from a mojo pipe into an [Image] object.
+void decodeImageFromDataPipe(int handle, ImageDecoderCallback callback)
     native "decodeImageFromDataPipe";
 
-void decodeImageFromList(Uint8List list, _ImageDecoderCallback callback)
+/// Convert an image file from a byte array into an [Image] object.
+void decodeImageFromList(Uint8List list, ImageDecoderCallback callback)
     native "decodeImageFromList";
 
 class Path extends NativeFieldWrapperClass2 {
@@ -335,6 +350,8 @@ abstract class Picture extends NativeFieldWrapperClass2 {
   /// canvas the option of just taking a ref.
   void playback(Canvas canvas) native "Picture_playback";
 
+  /// Release the resources used by this object. The object is no longer usable
+  /// after this method is called.
   void dispose() native "Picture_dispose";
 }
 

sky/engine/core/dart/window.dart

@@ -4,10 +4,17 @@
 
 part of dart_ui;
 
+/// Signature of callbacks that have no arguments and return no data.
 typedef void VoidCallback();
-typedef void _FrameCallback(Duration duration);
-typedef void _PointerPacketCallback(ByteData serializedPacket);
-typedef void _AppLifecycleStateCallback(AppLifecycleState state);
+
+/// Signature for [Window.onBeginFrame].
+typedef void FrameCallback(Duration duration);
+
+/// Signature for [Window.onPointerPacket].
+typedef void PointerPacketCallback(ByteData serializedPacket);
+
+/// Signature for [Window.onAppLifecycleStateChanged].
+typedef void AppLifecycleStateCallback(AppLifecycleState state);
 
 /// States that an application can be in.
 ///
@@ -103,19 +110,19 @@ class Window {
 
   /// A callback that is invoked when there is a transition in the application's
   /// lifecycle (such as pausing or resuming).
-  _AppLifecycleStateCallback onAppLifecycleStateChanged;
+  AppLifecycleStateCallback onAppLifecycleStateChanged;
 
   /// A callback that is invoked to notify the application that it is an
   /// appropriate time to provide a scene using the [SceneBuilder] API and the
   /// [render()] method. When possible, this is driven by the hardware VSync
   /// signal. This is only called if [scheduleFrame()] has been called since the
   /// last time this callback was invoked.
-  _FrameCallback onBeginFrame;
+  FrameCallback onBeginFrame;
 
   /// A callback that is invoked when pointer data is available. The data is
   /// provided in the form of a raw byte stream containing an encoded mojo
   /// PointerPacket.
-  _PointerPacketCallback onPointerPacket;
+  PointerPacketCallback onPointerPacket;
 
   /// The route or path that the operating system requested when the application
   /// was launched.
@@ -140,5 +147,7 @@ class Window {
   void flushRealTimeEvents() native "Scheduler_FlushRealTimeEvents";
 }
 
-/// The [Window] singleton.
+/// The [Window] singleton. This object exposes the size of the display, the
+/// core scheduler API, the input event callback, the graphics drawing API, and
+/// other such core services.
 final Window window = new Window._();