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Android Chromium WebView

WebView version historyAndroid <= J: custom WebKit-based “classic” WebViewAndroid K: Chromium 30/33-based WebViewAndroid L: Unbundled evergreen WebView, autoupdated via

Play Services

Organization of code

 

 

android.webkit.WebView

WebViewProvider

Chromium source tree

AwContents

ContentViewCore

“glue layer”

Android source tree

Rendering engine

MyWebViewApp

Android framework

android_webview/

Chromium content layer

How Rendering Work

rendering occurs in two phases: paint, composite.

painting is the population of layers’ backings (bitmaps with software rasterization; textures in hardware rasterization).

drawing is the compositor combining layers into the final screen image;

渲染过程

Threading model summaryChromeMulti-process UI thread GPU thread Texture upload thread Per renderer process:

o Blink threado CC impl threado Raster thread

WebViewSingle-process Combined UI + renderer CC

thread Android RenderThread (+in-

process GPU thread) Canvas/WebGL GPU thread Blink thread Raster thread

Blink进展 Binding Team

Layout Team

Memory Team。 BlinkAllocator； Oilpan（ Oilpan is a project to replace reference counting in Blink with a GC）

Paint Team。 Slimming Paint (Redesigning Painting and Compositing)

Style Team

Web Components Team

Animation Team

结论 UI线程很忙。 IO操作、 cpu密集操作不要放在 UI线程执行，开发中尽量减轻 UI的负担。 WebView有内存泄漏的问题。 硬件加速速度更快，但消耗更多内存，开发中需要考虑性能和内存的平衡。 WebView放在单独的进程运行。 WebView的性能在不断提高。

https://www.chromium.org/developers/design-documents

http://www.ituring.com.cn/minibook/705

http://blog.csdn.net/hongbomin?viewmode=contents

http://blog.csdn.net/Luoshengyang