![]() ![]() For optimum performance, the embedder should create a dedicated thread per task runner. The engine does not care if the references are to the same task runner, or, if multiple task runners are serviced on the same thread. The Flutter engine requires the embedder to give it references to 4 task runners. Neither the Flutter engine or the embedder have any access to the threads in this pool. In addition to the threads managed by the embedder for the engine, the Dart VM also has its own thread pool. The embedder gives the Flutter engine task runners for the threads it manages. Instead, it is the responsibility of the embedder to create and manage threads (and their message loops) for the Flutter engine. The Flutter engine does not create or manage its own threads. The shells can also communicate directly to Dart code via Platform Channels which bypass the engine. The Dart VM implements the normal Dart core libraries, plus an additional library called dart:ui to provide low-level access to Skia features and the shell. The shells implement platform-specific code such as communicating with IMEs (on-screen keyboards) and the system's application lifecycle events. We also have an embedder API which allows Flutter's engine to be used as a library (see Custom Flutter Engine Embedders). Different platforms have different shells, for example we have shells for Android and iOS. Part of app template generated by flutter create, owned by app developer.įlutter's engine takes core technologies, Skia, a 2D graphics rendering library, and Dart, a VM for a garbage-collected object-oriented language, and hosts them in a shell.Composes the pieces exposed by the platform-specific API of the Embedder into an app package runnable on the target platform.Exposes platform-specific API to integrate the Embedder into apps.Coordinates with the underlying operating system for access to services like rendering surfaces, accessibility, and input.Integrates with a specific platform via the Engine's Embedder API.Exposes its functionality via its dart:ui API to the framework.graphics, text layout, Dart runtime, etc.). Provides low-level implementation of Flutter's core APIs (e.g.Responsible for rasterizing composited scenes.Composites the app's widget tree into a scene.widgets, hit-testing, gesture detection, accessibility, text input, etc.). Provides higher-level API to build high-quality apps (e.g.The legend below clarifies some of the terminology commonly used to describe the pieces of a Flutter app. ![]() It shows where the Flutter Engine sits in this stack, highlights API boundaries, and identifies the repositories where the individual pieces live. ![]() The following diagram gives an overview of the pieces that make up a regular Flutter app generated by flutter create. It implements Flutter's core libraries, including animation and graphics, file and network I/O, accessibility support, plugin architecture, and a Dart runtime and toolchain for developing, compiling, and running Flutter applications. The Flutter Engine is a portable runtime for high-quality cross-platform applications.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |