Datasets:
Ekhlass
/
Flutter_Documentation

Dataset card Data Studio Files
xet
 Community
1
text
stringlengths
1
474
there are several options to avoid this exception.
The following solutions are listed in order of preference.<topic_end>
<topic_start>
Wrap the plugin
In most cases, the best approach is to wrap plugin
calls in your own API,
and provide a way of mocking your own API in tests.This has several advantages:<topic_end>
<topic_start>
Mock the plugin’s public API
If the plugin’s API is already based on class instances,
you can mock it directly, with the following caveats:<topic_end>
<topic_start>
Mock the plugin’s platform interface
If the plugin is a federated plugin,
it will include a platform interface that allows
registering implementations of its internal logic.
You can register a mock of that platform interface
implementation instead of the public API with the
following caveats:An example of when this might be necessary is
mocking the implementation of a plugin used by
a package that you rely on,
rather than your own code,
so you can’t change how it’s called.
However, if possible,
you should mock the dependency that uses the plugin instead.<topic_end>
<topic_start>
Mock the platform channel
If the plugin uses platform channels,
you can mock the platform channels using
TestDefaultBinaryMessenger.
This should only be used if, for some reason,
none of the methods above are available,
as it has several drawbacks:Because of these limitations, TestDefaultBinaryMessenger
is mainly useful in the internal tests
of plugin implementations,
rather than tests of code using plugins.You might also want to check out
Testing plugins.
<topic_end>
<topic_start>Debugging Flutter apps
There’s a wide variety of tools and features to help debug
Flutter applications. Here are some of the available tools:<topic_end>
<topic_start>
Other resources
You might find the following docs useful:
<topic_end>
<topic_start>Debug Flutter apps from code
This guide describes which debugging features you can enable in your code.
For a full list of debugging and profiling tools, check out the
Debugging page.info Note
If you are looking for a way to use GDB to remotely debug the
Flutter engine running within an Android app process,
check out flutter_gdb.<topic_end>
<topic_start>
Add logging to your application
info Note
You can view logs in DevTools’ Logging view
or in your system console. This sections
shows how to set up your logging statements.You have two options for logging for your application.Import dart:io and invoking methods on
stderr and stdout. For example:
<code_start>stderr.writeln('print me');<code_end>
If you output too much at once, then Android might discard some log lines.
To avoid this outcome,
use debugPrint() from Flutter’s foundation library.
This wrapper around print throttles the output to avoid the Android kernel
dropping output.You can also log your app using the dart:developer log() function.
This allows you to include greater granularity and more information
in the logging output.<topic_end>
<topic_start>Example 1
<code_start>import 'dart:developer' as developer;
void main() {
developer.log('log me', name: 'my.app.category');
developer.log('log me 1', name: 'my.other.category');
developer.log('log me 2', name: 'my.other.category');
}<code_end>
You can also pass app data to the log call.
The convention for this is to use the error: named
parameter on the log() call, JSON encode the object
you want to send, and pass the encoded string to the
error parameter.<topic_end>
<topic_start>Example 2
<code_start>import 'dart:convert';
import 'dart:developer' as developer;
void main() {
var myCustomObject = MyCustomObject();
developer.log(
'log me',
name: 'my.app.category',
error: jsonEncode(myCustomObject),
);
}<code_end>
DevTool’s logging view interprets the JSON encoded error parameter
as a data object.
DevTool renders in the details view for that log entry.<topic_end>
<topic_start>
Set breakpoints
You can set breakpoints in DevTools’ Debugger or
in the built-in debugger of your IDE.To set programmatic breakpoints:Insert programmatic breakpoints using the debugger() statement.
This statement takes an optional when argument.
This boolean argument sets a break when the given condition resolves to true.Example 3 illustrates this.<topic_end>
<topic_start>Example 3