I'm making a library for persistence implementation. For that I want to use reflection to be able to restore an object from the storage.
I can't use dart:mirrors because this library will be use also in Flutter application. So I'm trying to use reflectable package. And here I'm getting a major issue with understanding of how it should work. The doc tells reflectable uses build package and that some files must be generated. But I couldn't find anywhere whether this generation should happen for each file in my library package or just those where reflectable is used.
My library project structure is standard:
/examples
/lib
/lib/src
/lib/my_package.dart
/test
/pubspec.yaml
When I run dart run build_runner or dart run build_runner lib from the project root I see for each file in /example and /tests a matching file is generated. But in /lib folder nothing is generated. Only file where I'm intending to use reflectable is /lib/src/persistence/persistence_model.dart. I've created a file /lib/build.yaml of following content:
targets:
$default:
builders:
reflectable:
generate_for:
- src/persistence/persistence_model.dart
options:
formatted: true
but it seems to have no effect.
So, what should be right approach?
And probably a side question or rather consideration: isn't using reflection in Dart and Flutter excessively complex comparing to other languages (Python, C#, Java)?
Related
I'm trying to run my flutter-app in web. So I created a web folder and added all the necessary things. Since I'm using the objectBox in multiple dart files, I'm getting error based on ObjectBox.
So what I did to find the issue was, In the main.dart file i'm just trying to display only simple Container widget containing a text. But still I'm getting the same error related to objectBox with its entity.
So my doubt is, Is it compiling all the dart files located in lib? If then, can I exclude them.
I have tried(created a build.yaml file) to exclude all my files which are using ObjectBox.
My build.yaml file:
targets:
$default:
sources:
exclude:
- lib/test_driver/runner.dart
- lib/tools/**.dart
I have project structure
-core_data
-core_domain
-core_ui
-core_launcher
The dependency of these 4 projects is
core_launcher -> core_ui -> core_domain -> core_data
4 projects are located in the same directory and I include one to another via pubspec.yaml file (for example core_launcher/pubspec.yaml):
dependencies:
flutter:
sdk: flutter
core_ui:
path: ../core_ui
The same thing I do with all projects to make dependency hierarchy.
The problem is that I can import all files from core_ui subproject when I'm currently editing some file in core_launcher but VSCode doesn't see any classes from his parents
(core_domain & core_data).
However, I can input import 'blah-blah-blah manually and VSCode see this class and import works well, but I can't do that with hit Alt+Enter that I do for fast-import.
So, I'm wondering why autocomplete is not working for inherited libraries.
Somebody had the same issue?
Code completion will only show classes from your direct dependencies. There are two possible reasons for this:
Relying on transitive dependencies is not a good idea, because it's possible that your dependencies will remove or change their dependencies and not consider that a breaking change.
If code completion listed all classes from all transitive dependencies the code completion list would be huge and include classes from packages you do not recognise (because they are just other packages dependencies). This would be a bad user experience and make it easy to accidentally rely on packages that are not listed in your pubspec.yaml.
The fix is to explicitly list core_domain and core_data in your pubspec.yaml too, because if your project is using classes from them, then they are dependencies.
I have a project that I plan on developing in modules, the final application will be any number of the modules built together based on a configuration. I have a swift package that has all of my common code it it, we can call that the platform package. I then went to create my first feature, this went just fine however when I created the wrapper application to pull in each feature, I got this error from SPM in xcode11:
package 'Platform' is required using a revision-based requirement and it depends on local package
'Feature1', which is not supported.
Looking at the code base for SPM here (line 72)
https://github.com/apple/swift-package-manager/blob/master/Sources/PackageGraph/DependencyResolver.swift
It looks like this is something that is just not supported, the mixing of local and remote dependencies? Is this a limitation of SPM / should I be trying to use another tool for this type of app architecture?
In my case, I was trying to add a package, which I was developing, and its Package.swift contained dependencies of the form:
dependencies: [
.package(path: "../PackageName"),
// etc
Changing the references to specific repos solved the problem:
dependencies: [
.package(path: "http://github.com/..."),
// etc
I have stumbled upon a problem in importing the package in Flutter, I tried to solve this by running flutter packages get and also shutting down the project in Android studio and reopening it.
import 'package:task_02_category_widget/category.dart';
Here is the line above, and the error I'm running into when I run it gives the following error in the console.
Your application could not be compiled, because its dependencies could
not be established.
The following Dart file:
/Users/username/Documents/flutter_rectangle_2/lib/main.dart
...refers, in an import, to the following library:
package:task_02_category_widget/category.dart
That library is in a package that is not known. Maybe you forgot to
mention it in your pubspec.yaml file?
If task_02_category_widget/category.dart is part of an old project you are reusing you should put it in a folder in your flutter application and include it like "../ folder /task_02_category_widget/category.dart ". If it is part of github repository you have copy pasted from, just copy the file and use the step above. Most probably you are looking for that . In any other case check here to find the source code.
You should have in your project at a file called pubspec.yaml a definition like this:
name: my_app
dependencies:
task_02_category_widget:
Let’s say that your package is laid out as follows:
task_02_category_widget/
lib/
category.dart
Then, you can import it:
import 'package:task_02_category_widget/category.dart';
More information:
https://www.dartlang.org/tools/pub/get-started
https://www.dartlang.org/guides/libraries/create-library-packages
How do I create a package in the new Dart Editor?
There is no "Add Pub support" checkbox?
Also how to create "packages" with the new editor?
Is a tutorial out there that describes the process with the new Editor?
To create a package named mypackage.
For Dart package:
dart create --template=package-simple mypackage
For Flutter package:
flutter create --template=package mypackage
From the Dart/Flutter Documentation:
Step 1: Create the package
To create a Flutter package, use the --template=package flag with flutter create:
flutter create --template=package hello
This creates a package project in the hello folder with the following content:
LICENSE
A (mostly) empty license text file.
test/hello_test.dart
The unit tests for the package.
hello.iml
A configuration file used by the IntelliJ IDEs.
.gitignore
A hidden file that tells Git which files or folders to ignore in a project.
.metadata
A hidden file used by IDEs to track the properties of the Flutter project.
pubspec.yaml
A yaml file containing metadata that specifies the package’s dependencies. Used by the pub tool.
README.md
A starter markdown file that briefly describes the package’s purpose.
lib/hello.dart
A starter app containing Dart code for the package.
.idea/modules.xml, .idea/modules.xml, .idea/workspace.xml**
A hidden folder containing configuration files for the IntelliJ IDEs.
CHANGELOG.md
A (mostly) empty markdown file for tracking version changes to the package.
There's no such possibilty in the Dart Editor for now. To create a package follow these steps :
create an New Application mylib without sample content
add a pubspec.yaml file
add a lib folder
create a mylib.dart containing the code you want to package
See the Package layout conventions for more informations.
You can create a dart project following the flutter way that allow you to auto generate the structure and the hierarchy of the package.
Follow below steps to create a package in DART:
Step 1: Create the package
$ flutter create --template=package hello
Step 2: Implement the package
For pure Dart packages, simply add the functionality inside the main lib/.dart file, or in several files in the lib directory.
To test the package, add unit tests in a test directory.
For additional details on how to organize the package contents, see the Dart library package documentation:
https://flutter.dev/docs/development/packages-and-plugins/developing-packages
Any dart app is a package. To create a new Dart app use:
dart create my_package