text
stringlengths
1
372
is delegated to the compiled flutter and app code.
this is similar to the way many game engines work.
during debug mode, flutter uses a virtual machine (vm)
to run its code in order to enable stateful hot reload,
a feature that lets you make changes to your running code
without recompilation. you’ll see a “debug” banner in
the top right-hand corner of your app when running in this mode,
to remind you that performance is not characteristic of
the finished release app.
<topic_end>
<topic_start>
how does flutter run my code on iOS?
the engine’s c and c++ code are compiled with LLVM.
the dart code (both the SDK’s and yours)
are ahead-of-time (aot) compiled into a native, ARM library.
that library is included in a “runner” iOS project,
and the whole thing is built into an .ipa.
when launched, the app loads the flutter library.
any rendering, input or event handling, and so on,
are delegated to the compiled flutter and app code.
this is similar to the way many game engines work.
during debug mode, flutter uses a virtual machine (vm)
to run its code in order to enable stateful hot reload,
a feature that lets you make changes to your
running code without recompilation. you’ll see
a “debug” banner in the top right-hand corner of
your app when running in this mode, to remind you that
performance is not characteristic of the finished release app.
<topic_end>
<topic_start>
does flutter use my operating system’s built-in platform widgets?
no. instead, flutter provides a set of widgets
(including material design and cupertino (ios-styled) widgets),
managed and rendered by flutter’s framework and engine.
you can browse a catalog of flutter’s widgets.
we believe that the end result is higher quality apps.
if we reused the built-in platform widgets,
the quality and performance of flutter apps would be limited
by the flexibility and quality of those widgets.
in android, for example, there’s a hard-coded set
of gestures and fixed rules for disambiguating them.
in flutter, you can write your own gesture recognizer
that is a first class participant in the gesture system.
moreover, two widgets authored by different people can
coordinate to disambiguate gestures.
modern app design trends point towards designers and
users wanting more motion-rich UIs and brand-first designs.
in order to achieve that level of customized, beautiful design,
flutter is architectured to drive pixels instead
of the built-in widgets.
by using the same renderer, framework, and set of widgets,
it’s easier to publish for multiple platforms from the same
codebase, without having to do careful and costly planning
to align different feature sets and API characteristics.
by using a single language, a single framework,
and a single set of libraries for all of your code
(regardless if your UI is different for each platform or not),
we also aim to help lower app development and maintenance costs.
<topic_end>
<topic_start>
what happens when my mobile OS updates and introduces new widgets?
the flutter team watches the adoption and demand for new mobile
widgets from iOS and android, and aims to work with the community
to build support for new widgets. this work might come in the form
of lower-level framework features, new composable widgets,
or new widget implementations.
flutter’s layered architecture is designed to support numerous
widget libraries, and we encourage and support the community in
building and maintaining widget libraries.
<topic_end>
<topic_start>
what happens when my mobile OS updates and introduces new platform capabilities?
flutter’s interop and plugin system is designed to allow
developers to access new mobile OS features and capabilities
immediately. developers don’t have to wait for the flutter team
to expose the new mobile OS capability.
<topic_end>
<topic_start>
what operating systems can i use to build a flutter app?
flutter supports development using linux, macOS, ChromeOS,
and windows.
<topic_end>
<topic_start>
what language is flutter written in?
dart, a fast-growing modern language optimized
for client apps. the underlying graphics framework
and the dart virtual machine are implemented in C/C++.
<topic_end>
<topic_start>
why did flutter choose to use dart?
during the initial development phase,
the flutter team looked at a lot of
languages and runtimes, and ultimately
adopted dart for the framework and widgets.
flutter used four primary dimensions for evaluation,
and considered the needs of framework authors,
developers, and end users. we found many languages
met some requirements, but dart scored highly on
all of our evaluation dimensions and met all our
requirements and criteria.