If multiple mixins in the same app try to use settings, will they overwrite each other? In other words can multiple mixins have getSettingsFields?
getSettingsFields: function() {
return [
{
field123: 'url',
xtype: 'rallytextfield'
}
];
}
I think the last mixin in will win and replace all the other getSettingsFields methods. A lot of the time we'll just have one getSettingsField method in the actual app class but delegate the implementation out to a separate class:
https://github.com/RallyApps/app-catalog/blob/master/src/apps/board/BoardApp.js#L134
https://github.com/RallyApps/app-catalog/blob/master/src/apps/board/Settings.js
Related
Ant Design Vue v1 provided a documented example for writing custom form components.
The same approach does not apply to version 2x.
How can a custom form component be implemented in AntDV 2x (vue 3) using useForm?
I believe I have figured this out. Previously your custom component needed to emit a change event:
methods: {
handleChange(value) {
this.emit('change', value);
},
},
Having looked through the source code I learned that you also need to emit an update:value event as well:
methods: {
handleChange(value) {
this.emit('update:value', value);
this.emit('change', value);
},
},
I'm trying to use Injector to inject my component/service but one of them requires NgZone as its dependency. From https://angular.io/api/core/Injector
export MyComponent{
constructor() {
const injector = Injector.create({
providers: [
{ provide: NgZone, deps: [ ] },
{ provide: MyService, deps: [ NgZone ] }
]
});
this.myService = injector.get(MyService);
}
}
Then in child class:
export MyOtherComponent extends MyComponent {
constructor() {
super();
}
public helloWorld() {
this.myService.stuff();
}
}
But I'm getting the following error:
ERROR Error: StaticInjectorError[MyService -> NgZone]:
NullInjectorError: No provider for NgZone!
at NullInjector.get (core.js:8896)
I tried with a dummy service that don't have anything in the constructor, and it worked.
Is there a way to provide NgZone manually through the deps like that?
Is there another way to get the "global" NgZone object (there should only be 1 instance of NgZone running right?)
MyService is also a downgraded service and is being used in both AngularJS and Angular7, not sure if that changes anything.
Edit: Reason I'm trying to do this, is because MyComponent is a component base class that will get extends upon and have many child class extending on that. If I could do it like this by manually injecting it internally, then I don't need to pass all those dependencies from the children. Imagine I have 6-7 dependencies and 30+ childrens, and lets say I need some new dependencies, I'd have to update every single one of them...
You could inject injector — it would be a single dependency. And all your children could then get what they need from this injector. Yes, you would need to provide that injector through your inheritance chain of super() calls, but at least it would be just one thing.
There's also this:
https://github.com/angular/angular/issues/16566#issuecomment-338188342
This comment states it is possible to use DI in abstract classes if you decorate them. As for NgZone instance — yes, I believe there must be only one and I also tried to get a hold of it once but couldn't come up with an elegant solution.
Guess I was brain dead last night. This morning after digging deeper, I think I've found a way to grab the global Zone and it seems to work (it triggered the change detection).
Since #waterplea also have the assumption that there should only be 1 instance of the NgZone, I decided to just look around in console and what do you know.
Then I tried to just pass the global Zone to it like this:
{ provide: NgZone, useValue: Zone },
And it gave me the error that this.ngZone.run is undefined. OK... digging deeper, oh hey, there is a root object in Zone and hey, look, a run function!
So I went and updated the code to this and it worked.
{ provide: NgZone, useValue: Zone.root },
In my controller, via service, I get from DB a list of the names of widgets (eg. chart, calendar, etc). Every widget implements WidgetInterface and may need other services as its own dependencies. The list of widgets can be different for each user, so I don't know which widgets / dependencies I will need in my controller. Generally, I put dependencies via DI, using factories, but in this case I don't know dependencies at the time of controller initialization.
I want to avoid using service locator directly in controller. How can I manage that issue? Should I get a list of the names of widgets in controller factory? And depending on widgets list get all dependencies and put them to controller?
Thanks, Tom
Solution
I solved my issue in a way that suggested Kwido and Sven Buis, it means, I built my own Plugin Manager.
Advantages: I do not need use service locator directly in controller and I have clear and extensible way to get different kinds of widgets.
Thank you.
Create your own Manager, like some sort of ServiceManager, for your widgets.
class WidgetManager extends AbstractPluginManager
Take a look at: Samsonik tutorial - pluginManager. So this way you can inject the WidgetManager and only retrieve the widgets from this manager as your function: validatePlugin, checks whether or not the fetched instance is using the WidgetInterface. Keep in mind that you can still call the parent ServiceManager.
Or keep it simple and build a plugin for your controller that maps your widget names to the service. This plugin can then use the serviceLocator/Manager to retrieve your widget(s), whether they're created by factories or invokableFactories. So you dont inject all the widget directly but only fetch them when they're requested. Something realy simplistic:
protected $map = [
// Widget name within the plugin => Name or class to call from the serviceManager
'Charts' => Widget\Charts::class,
];
public function load($name)
{
if (array_key_exists($name, $this->map)) {
return $this->getServiceManager()->get($this->map[$name]);
}
return null;
}
Injecting all the Widgets might be bad for your performance so you might consider something else, as when the list of your widgets grow so will the time to handle your request.
Hope this helped you and pushed you in some direction.
This indeed is a interesting question. You could consider using Plugins for the widgets, which can be loaded on the fly.
Depency injection is a good practise, but sometimes, with dynamic content, impossible to implement.
Another way to do this, is to make your own widget-manager. This manager then can load the specific widgets you need. The widget-manager can be injected into the controller.
Edit:
As you can see above, same idea from #kwido.
I would use a separate service and inject that into the controller.
interface UserWidgetServiceInterface
{
public function __construct(array $widgets);
public function getWidget($name);
}
The controller factory
class MyControllerFactory
{
public function __invoke(ControllerManager $controllerManager, $name, $requestedName)
{
$serviceLocator = $controllerManager->getServiceLocator();
$userWidgetService = $serviceLocator->get('UserWidgetService');
return new MyController($userWidgetService);
}
}
Then the logic to load the widgets would be moved to the UserWidgetServiceFactory.
public function UserWidgetServiceFactory
{
public function __invoke(ServiceManager $serviceLocator, $name, $requestedName)
{
$userId = 123; // Load from somewhere e.g session, auth service.
$widgetNames = $this->getWidgetNames($serviceLocator, $userId);
$widgets = $this->loadWidgets($serviceManager, $widgetNames);
return new UserWidgetService($widgets);
}
public function getWidgetNames(ServiceManager $sm, $userId)
{
return ['foo','bar'];
}
public function loadWidgets(serviceManager $sm, array $widgets)
{
$w = [];
foreach($widgets as $widgetName) {
$w[$widgetName] = $sm->get($widgetName);
}
return $w;
}
}
The call to loadWidgets() would eager load all the widgets; should you wish to optimise this you could register your widgets as LazyServices
As per Grails documentation
Grails also lets you write your domain model in Java or reuse an existing one that already has Hibernate mapping files. Simply place the mapping files into grails-app/conf/hibernate and either put the Java files in src/java or the classes in the project's lib directory if the domain model is packaged as a JAR. You still need the hibernate.cfg.xml though!
So This is exactley what i did.
I have used java domain model and hibernate.cfg.xml file for mapping. I also use
{DomainName}Constraints.groovy for adding Grails constraints. I also used to add functions to {DomainName}Constraints. For example, below is the content of my EmployeeConstraints.groovy
Employee.metaClass.static.findByDepartment = {depCode ->
createCriteria().list {
department{
inList ('code', depCode)
}
}
}
Now this works fine. But, when i add projection to it(code below), just to get the employee code.
Employee.metaClass.static.findByDepartment = {depCode ->
createCriteria().list {
projections { property('empCode', 'empCode') }
department { inList ('code', depCode) }
}
}
I get the below error..
" No signature of method: com.package.script142113.projections() is applicable for argument types.. "
Can someone point me to whats wrong with the code?
Thanks!
The property projection is used to return a subset of an object's properties. For example, to return just the foo and bar properties use:
projections {
property('foo')
property('bar')
}
You're getting an error because you've called the property method with 2 arguments instead of one.
By the way, I see another potential with your code. Grails will automatically create a dynamic finder findByDepartment that has the same name as the method your trying to add via the meta-class. I have no idea which one will take precendence, but I would suggest you avoid this potential problem and simplify your code, by adding this query using Grails' named query support, and call it something like getByDepartment so that the name doesn't class with a dynamic finder.
The answer by Dónal should be the correct one, but I found a strange behavior with grails 3.1. I got the same message using this call:
Announcement.createCriteria().list {
projections {
property('id')
property('title')
}
} .collect { [id: it['id'], title: it['title']] } // it['id'] not found
I fixed it by removing projections closure:
Announcement.createCriteria().list {
property('id')
property('title')
} .collect { [id: it['id'], title: it['title']] } // got the it['id']
Hope this help.
The documentation only mentions nested types, but it's not clear if they can be used as namespaces. I haven't found any explicit mentioning of namespaces.
I would describe Swift's namespacing as aspirational; it's been given a lot of advertising that doesn't correspond to any meaningful reality on the ground.
For example, the WWDC videos state that if a framework you're importing has a class MyClass and your code has a class MyClass, those names do not conflict because "name mangling" gives them different internal names. In reality, however, they do conflict, in the sense that your own code's MyClass wins, and you can't specify "No no, I mean the MyClass in the framework" — saying TheFramework.MyClass doesn't work (the compiler knows what you mean, but it says it can't find such a class in the framework).
My experience is that Swift therefore is not namespaced in the slightest. In turning one of my apps from Objective-C to Swift, I created an embedded framework because it was so easy and cool to do. Importing the framework, however, imports all the Swift stuff in the framework - so presto, once again there is just one namespace and it's global. And there are no Swift headers so you can't hide any names.
EDIT: In seed 3, this feature is now starting to come online, in the following sense: if your main code contains MyClass and your framework MyFramework contains MyClass, the former overshadows the latter by default, but you can reach the one in the framework by using the syntax MyFramework.MyClass. Thus we do in fact have the rudiments of a distinct namespace!
EDIT 2: In seed 4, we now have access controls! Plus, in one of my apps I have an embedded framework and sure enough, everything was hidden by default and I had to expose all the bits of the public API explicitly. This is a big improvement.
Answered by SevenTenEleven in the Apple dev forum:
Namespaces are not per-file; they're per-target (based on the
"Product Module Name" build setting). So you'd end up with something
like this:
import FrameworkA
import FrameworkB
FrameworkA.foo()
All Swift declarations are considered to be part of
some module, so even when you say "NSLog" (yes, it still exists)
you're getting what Swift thinks of as "Foundation.NSLog".
Also Chris Lattner tweeted about namespacing.
Namespacing is implicit in Swift, all classes (etc) are implicitly
scoped by the module (Xcode target) they are in. no class prefixes
needed
Seems to be very different what I have been thinking.
While doing some experimentation with this I ended up creating these "namespaced" classes in their own files by extending the root "package". Not sure if this is against best practices or if it has any implications I'm mot aware of(?)
AppDelegate.swift
var n1 = PackageOne.Class(name: "Package 1 class")
var n2 = PackageTwo.Class(name: "Package 2 class")
println("Name 1: \(n1.name)")
println("Name 2: \(n2.name)")
PackageOne.swift
import Foundation
struct PackageOne {
}
PackageTwo.swift
import Foundation
struct PackageTwo {
}
PackageOneClass.swift
extension PackageOne {
class Class {
var name: String
init(name:String) {
self.name = name
}
}
}
PackageTwoClass.swift
extension PackageTwo {
class Class {
var name: String
init(name:String) {
self.name = name
}
}
}
Edit:
Just found out that creating "subpackages" in above code wont work if using separate files. Maybe someone can hint on why that would be the case?
Adding following files to the above:
PackageOneSubPackage.swift
import Foundation
extension PackageOne {
struct SubPackage {
}
}
PackageOneSubPackageClass.swift
extension PackageOne.SubPackage {
class Class {
var name: String
init(name:String) {
self.name = name
}
}
}
Its throwing a compiler error:
'SubPackage' is not a member type of 'PackageOne'
If I move the code from PackageOneSubPackageClass.swift to PackageOneSubPackage.swift it works. Anyone?
Edit 2:
Fiddling around with this still and found out (in Xcode 6.1 beta 2) that by defining the packages in one file they can be extended in separate files:
public struct Package {
public struct SubPackage {
public struct SubPackageOne {
}
public struct SubPackageTwo {
}
}
}
Here are my files in a gist:
https://gist.github.com/mikajauhonen/d4b3e517122ad6a132b8
I believe this is achieved using:
struct Foo
{
class Bar
{
}
}
Then it can be accessed using:
var dds = Foo.Bar();
Namespaces are useful when you need to define class with the same name as class in existing framework.
Suppose your app has MyApp name, and you need to declare your custom UICollectionViewController.
You don't need to prefix and subclass like this:
class MAUICollectionViewController: UICollectionViewController {}
Do it like this:
class UICollectionViewController {} //no error "invalid redeclaration o..."
Why?. Because what you've declared is declared in current module, which is your current target. And UICollectionViewController from UIKit is declared in UIKit module.
How to use it within current module?
var customController = UICollectionViewController() //your custom class
var uikitController = UIKit.UICollectionViewController() //class from UIKit
How to distinguish them from another module?
var customController = MyApp.UICollectionViewController() //your custom class
var uikitController = UIKit.UICollectionViewController() //class from UIKit
Swift uses modules much like in python (see here and here) and as #Kevin Sylvestre suggested you can also use the nested types as namespaces.
And to extend the answer from #Daniel A. White, in WWDC they were talking about the modules in swift.
Also here is explained:
Inferred types make code cleaner and less prone to mistakes, while
modules eliminate headers and provide namespaces.
You can use extension to use the mentioned structs approach for namespacing without having to indent all of your code towards the right. I've been toying with this a bit and I'm not sure I'd go as far as creating Controllers and Views namespaces like in the example below, but it does illustrate how far it can go:
Profiles.swift:
// Define the namespaces
struct Profiles {
struct Views {}
struct ViewControllers {}
}
Profiles/ViewControllers/Edit.swift
// Define your new class within its namespace
extension Profiles.ViewControllers {
class Edit: UIViewController {}
}
// Extend your new class to avoid the extra whitespace on the left
extension Profiles.ViewControllers.Edit {
override func viewDidLoad() {
// Do some stuff
}
}
Profiles/Views/Edit.swift
extension Profiles.Views {
class Edit: UIView {}
}
extension Profiles.Views.Edit {
override func drawRect(rect: CGRect) {
// Do some stuff
}
}
I haven't used this in an app since I haven't needed this level of separation yet but I think it's an interesting idea. This removes the need for even class suffixes such as the ubiquitous *ViewController suffix which is annoyingly long.
However, it doesn't shorten anything when it's referenced such as in method parameters like this:
class MyClass {
func doSomethingWith(viewController: Profiles.ViewControllers.Edit) {
// secret sauce
}
}
Even though it is possible to implement namespaces using Framework and Libraries but the best solution is to use local packages using Swift Package Manager. Besides having access modifiers, this approach has some other benefits. As in Swift Package Manager, the files are managed based on the directory system, not their target member ship, you won't have to struggle with merge conflicts that arise frequently in teamworks. Furthermore, there is no need to set file memberships.
To check how to use local Swift packages refer to the following link:
Organizing Your Code with Local Packages
In case anyone was curious, as of June 10th 2014, this is a known bug in Swift:
From SevenTenEleven
"Known bug, sorry! rdar://problem/17127940 Qualifying Swift types by their module name doesn't work."