Datasets:
Ekhlass
/
flutter_docs

Dataset card Data Studio Files
xet
Community
1
text
stringlengths
1
372
custom channels and codecs
besides the above mentioned MethodChannel,
you can also use the more basic
BasicMessageChannel, which supports basic,
asynchronous message passing using a custom message codec.
you can also use the specialized BinaryCodec,
StringCodec, and JSONMessageCodec
classes, or create your own codec.
you might also check out an example of a custom codec
in the cloud_firestore plugin,
which is able to serialize and deserialize many more
types than the default types.
<topic_end>
<topic_start>
channels and platform threading
when invoking channels on the platform side destined for flutter,
invoke them on the platform’s main thread.
when invoking channels in flutter destined for the platform side,
either invoke them from any isolate that is the root
isolate, or that is registered as a background isolate.
the handlers for the platform side can execute on the platform’s main thread
or they can execute on a background thread if using a task queue.
you can invoke the platform side handlers asynchronously
and on any thread.
info note
on android, the platform’s main thread is sometimes
called the “main thread”, but it is technically defined
as the UI thread. annotate methods that need
to be run on the UI thread with @uithread.
on iOS, this thread is officially
referred to as the main thread.
<topic_end>
<topic_start>
using plugins and channels from background isolates
plugins and channels can be used by any isolate, but that isolate has to be
a root isolate (the one created by flutter) or registered as a background
isolate for a root isolate.
the following example shows how to register a background isolate in order to
use a plugin from a background isolate.
<topic_end>
<topic_start>
executing channel handlers on background threads
in order for a channel’s platform side handler to
execute on a background thread, you must use the
task queue API. currently this feature is only
supported on iOS and android.
in java:
in kotlin:
in swift:
info note
in release 2.10, the task queue API is only available on the master channel
for iOS.
in Objective-C:
info note
in release 2.10, the task queue API is only available on the master channel
for iOS.
<topic_end>
<topic_start>
jumping to the UI thread in android
to comply with channels’ UI thread requirement,
you might need to jump from a background thread
to android’s UI thread to execute a channel method.
in android, you can accomplish this by post()ing a
runnable to android’s UI thread looper,
which causes the runnable to execute on the
main thread at the next opportunity.
in java:
in kotlin:
<topic_end>
<topic_start>
jumping to the main thread in iOS
to comply with channel’s main thread requirement,
you might need to jump from a background thread to
iOS’s main thread to execute a channel method.
you can accomplish this in iOS by executing a
block on the main dispatch queue:
in Objective-C:
in swift:
<topic_end>
<topic_start>
automatic platform adaptations
info note
as of the flutter 3.16 release, material 3
replaces material 2 as the default theme
on all flutter apps that use material.
<topic_end>
<topic_start>
adaptation philosophy
in general, two cases of platform adaptiveness exist:
this article mainly covers the automatic adaptations
provided by flutter in case 1 on android and iOS.
for case 2, flutter bundles the means to produce the
appropriate effects of the platform conventions but doesn’t
adapt automatically when app design choices are needed.
for a discussion, see issue #8410 and the
Material/Cupertino adaptive widget problem definition.
for an example of an app using different information
architecture structures on android and iOS but sharing
the same content code, see the platform_design code samples.
info