I'm having trouble converting my project to Swift 3. In previous version of Swift I can declare a class under GKComponentSystem like:
class EnemyMoveComponentSystem: GKComponentSystem {
}
However in swift 3 it forces me to add < GKComponent > in the end as:
class EnemyMoveComponentSystem: GKComponentSystem <GKComponent> {
func updateWithDeltaTime(seconds: TimeInterval, gameScene: GameScene) {
for component in components {
print("something")
}
}
}
But it seems that I can't access each individual component within the system like before
for component in components {
print("something")
}
The line print("something") was never triggered.
How can I fix this?
Any help is appreciated!
Found out what the problem was. I forgot to link the entity to the component system.
.addComponent(foundIn: Entity)
Related
In the Apple developer docs chapter "There and Back Again" the watch app's App is written like this:
#main
struct MyWatchApp: App {
#WKExtensionDelegateAdaptor(ExtensionDelegate.self) var extensionDelegate
#SceneBuilder var body: some Scene {
WindowGroup {
NavigationView {
ContentView()
}
}
}
}
Unfortunately I get a purple runtime warning on my var declaration that says
#WKExtensionDelegateAdaptor should only be used within an extension based process
There must be something in Xcode that explicitly defines the App structure as "extension-based" but I can't find it!
Edit: More clarification... I am trying to handle the special method that gets called after you run the HealthKit method startWatchApp(with:completion:)
The special method for watch extensions is func handle(_ workoutConfiguration: HKWorkoutConfiguration)
I cannot seem to find a way to link this function on the new App structure for watch apps.
Ok, I found it. The solution is to simply replace WKExtensionDelegate with the new WKApplicationDelegate!
You can try this solution, it is simple and universal.
import WatchKit
class ExtensionDelegate: NSObject, WKExtensionDelegate {
static var current: ExtensionDelegate? {
return (WKExtension.shared().delegate as? ExtensionDelegate)
}
...
}
Then access this current instance like below, because it is Singleton, you can access it in the entire project scope.
ExtensionDelegate.current?.dosomething()
I'm using nativescript angular. I have a class called SomeClass that access the native API of iOS and Android separately.
I've written two files:
someclass.android.ts
export class SomeClass {
someFunction() {
if(isAndroid) {
// do some android specific code
}
}
}
someclass.ios.ts
export class SomeClass {
someFunction() {
if(isIOS) {
// do some ios specific code
}
}
}
Now, in app.component.ts, I'm using SomeClass like this:
import { SomeClass } from './../shared-code/someclass';
without .android.ts or .ios.ts, to enable nativescript to pick the right file depending on the running platform.
and then in the code, I user SomeFunction like this:
...
const someClass = new SomeClass();
someClass.someFunction();
...
With this setting, everything works perfectly on both iOS and Android, but I get the following error
error TS2307: Cannot find module './../shared-code/someclass'.
Do you have any idea how to tell nativescript/tslint to take into account the .android and .ios files and not to display this error?
Thanks
Here's the solution:
Alongside 'someclass.ios.ts' and 'someclass.android.ts', create a definitions file and name it 'someclass.d.ts' (Not index.d.ts). No need to put the files in a separate folder.
In someclass.d.ts, export declare the class like this:
export declare class SomeClass {
/**
* someFunction, is a function that does this and that (description)
*/
someFunction(): void;
}
Then, you can use this from another file like this:
In app.component.ts:
import { SomeClass } from './../shared-code/someclass';
Remember to use /someclass without any extensions.
This would solve build and tslint errors.
I have lots of code in Swift 2.x (or even 1.x) projects that looks like this:
// Move to a background thread to do some long running work
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0)) {
let image = self.loadOrGenerateAnImage()
// Bounce back to the main thread to update the UI
dispatch_async(dispatch_get_main_queue()) {
self.imageView.image = image
}
}
Or stuff like this to delay execution:
dispatch_after(dispatch_time(DISPATCH_TIME_NOW, Int64(0.5 * Double(NSEC_PER_SEC))), dispatch_get_main_queue()) {
print("test")
}
Or any of all kinds of other uses of the Grand Central Dispatch API...
Now that I've opened my project in Xcode 8 (beta) for Swift 3, I get all kinds of errors. Some of them offer to fix my code, but not all of the fixes produce working code. What do I do about this?
Since the beginning, Swift has provided some facilities for making ObjC and C more Swifty, adding more with each version. Now, in Swift 3, the new "import as member" feature lets frameworks with certain styles of C API -- where you have a data type that works sort of like a class, and a bunch of global functions to work with it -- act more like Swift-native APIs. The data types import as Swift classes, their related global functions import as methods and properties on those classes, and some related things like sets of constants can become subtypes where appropriate.
In Xcode 8 / Swift 3 beta, Apple has applied this feature (along with a few others) to make the Dispatch framework much more Swifty. (And Core Graphics, too.) If you've been following the Swift open-source efforts, this isn't news, but now is the first time it's part of Xcode.
Your first step on moving any project to Swift 3 should be to open it in Xcode 8 and choose Edit > Convert > To Current Swift Syntax... in the menu. This will apply (with your review and approval) all of the changes at once needed for all the renamed APIs and other changes. (Often, a line of code is affected by more than one of these changes at once, so responding to error fix-its individually might not handle everything right.)
The result is that the common pattern for bouncing work to the background and back now looks like this:
// Move to a background thread to do some long running work
DispatchQueue.global(qos: .userInitiated).async {
let image = self.loadOrGenerateAnImage()
// Bounce back to the main thread to update the UI
DispatchQueue.main.async {
self.imageView.image = image
}
}
Note we're using .userInitiated instead of one of the old DISPATCH_QUEUE_PRIORITY constants. Quality of Service (QoS) specifiers were introduced in OS X 10.10 / iOS 8.0, providing a clearer way for the system to prioritize work and deprecating the old priority specifiers. See Apple's docs on background work and energy efficiency for details.
By the way, if you're keeping your own queues to organize work, the way to get one now looks like this (notice that DispatchQueueAttributes is an OptionSet, so you use collection-style literals to combine options):
class Foo {
let queue = DispatchQueue(label: "com.example.my-serial-queue",
attributes: [.serial, .qosUtility])
func doStuff() {
queue.async {
print("Hello World")
}
}
}
Using dispatch_after to do work later? That's a method on queues, too, and it takes a DispatchTime, which has operators for various numeric types so you can just add whole or fractional seconds:
DispatchQueue.main.asyncAfter(deadline: .now() + 0.5) { // in half a second...
print("Are we there yet?")
}
You can find your way around the new Dispatch API by opening its interface in Xcode 8 -- use Open Quickly to find the Dispatch module, or put a symbol (like DispatchQueue) in your Swift project/playground and command-click it, then brouse around the module from there. (You can find the Swift Dispatch API in Apple's spiffy new API Reference website and in-Xcode doc viewer, but it looks like the doc content from the C version hasn't moved into it just yet.)
See the Migration Guide for more tips.
In Xcode 8 beta 4 does not work...
Use:
DispatchQueue.main.asyncAfter(deadline: .now() + 0.5) {
print("Are we there yet?")
}
for async two ways:
DispatchQueue.main.async {
print("Async1")
}
DispatchQueue.main.async( execute: {
print("Async2")
})
This one is good example for Swift 4 about async:
DispatchQueue.global(qos: .background).async {
// Background Thread
DispatchQueue.main.async {
// Run UI Updates or call completion block
}
}
in Xcode 8 use:
DispatchQueue.global(qos: .userInitiated).async { }
Swift 5.2, 4 and later
Main and Background Queues
let main = DispatchQueue.main
let background = DispatchQueue.global()
let helper = DispatchQueue(label: "another_thread")
Working with async and sync threads!
background.async { //async tasks here }
background.sync { //sync tasks here }
Async threads will work along with the main thread.
Sync threads will block the main thread while executing.
Swift 4.1 and 5. We use queues in many places in our code. So, I created Threads class with all queues. If you don't want to use Threads class you can copy the desired queue code from class methods.
class Threads {
static let concurrentQueue = DispatchQueue(label: "AppNameConcurrentQueue", attributes: .concurrent)
static let serialQueue = DispatchQueue(label: "AppNameSerialQueue")
// Main Queue
class func performTaskInMainQueue(task: #escaping ()->()) {
DispatchQueue.main.async {
task()
}
}
// Background Queue
class func performTaskInBackground(task:#escaping () throws -> ()) {
DispatchQueue.global(qos: .background).async {
do {
try task()
} catch let error as NSError {
print("error in background thread:\(error.localizedDescription)")
}
}
}
// Concurrent Queue
class func perfromTaskInConcurrentQueue(task:#escaping () throws -> ()) {
concurrentQueue.async {
do {
try task()
} catch let error as NSError {
print("error in Concurrent Queue:\(error.localizedDescription)")
}
}
}
// Serial Queue
class func perfromTaskInSerialQueue(task:#escaping () throws -> ()) {
serialQueue.async {
do {
try task()
} catch let error as NSError {
print("error in Serial Queue:\(error.localizedDescription)")
}
}
}
// Perform task afterDelay
class func performTaskAfterDealy(_ timeInteval: TimeInterval, _ task:#escaping () -> ()) {
DispatchQueue.main.asyncAfter(deadline: (.now() + timeInteval)) {
task()
}
}
}
Example showing the use of main queue.
override func viewDidLoad() {
super.viewDidLoad()
Threads.performTaskInMainQueue {
//Update UI
}
}
I'm trying to create asimple framework for testing with swift.
I had post the question in objective-c with "create the framework" before. It was resolved.
But I'm trying to create framework with swift.
I encounter the problem. I can't import the MyUtility file in header file.
like below:
Have anyone know how to import the file in my custom framework?
thank you very much.
============== edit ===========
for #Jerome L
In order to import Swift in objective C, you need to use the following syntax:
#import <ProductName/ProductModuleName-Swift.h>
So I guess in your case ti would be something like:
#import <MyFramewordSwift/MyUtility-Swift.h>
You can find more details here
I ran into the same issue. I have an all swift project and am making a pure swift framework. In order to get the target in the same project file to see the classes in my framework, I needed to explicitly add the modifier
public in front of my class declaration and in front of any method that I wanted to be accessible. Here is an example of one of the classes.
private let _sharedInstance = SomeManager()
public class SomeManager: NSObject {
//MARK: - Singleton instance
public class var sharedManager : SomeManager {
return _sharedInstance
}
public func outwardFacingMethod()-> Void {
internalMethod()
}
private func internalMethod()-> Void {
}
}
The documentation in this link states here but is a bit buried. If you scroll down to the section called Importing Code from Within the Same Framework Target it says
Because the generated header for a framework target is part of the
frameworkâs public interface, only declarations marked with the public
modifier appears in the generated header for a framework target.
I have been using MvvmCross on a cross platform mobile project and have 2 different views in a MonoTouch project that are using the same shared viewmodel and not sure how to go about structuring my code to navigate to different views using the same viewmodel in MvvmCross.
The default convention used by the MvvmCross platform is to automatically register all views using reflection.
This is done in the base Setup class - in https://github.com/slodge/MvvmCross/blob/master/Cirrious/Cirrious.MvvmCross/Platform/MvxBaseSetup.cs:
protected virtual void InitializeViews()
{
var container = this.GetService<IMvxViewsContainer>();
foreach (var pair in GetViewModelViewLookup())
{
Add(container, pair.Key, pair.Value);
}
}
where GetViewModelViewLookup returns a dictionary of ViewModel type to View type:
protected virtual IDictionary<Type, Type> GetViewModelViewLookup(Assembly assembly, Type expectedInterfaceType)
{
var views = from type in assembly.GetTypes()
let viewModelType = GetViewModelTypeMappingIfPresent(type, expectedInterfaceType)
where viewModelType != null
select new { type, viewModelType };
return views.ToDictionary(x => x.viewModelType, x => x.type);
}
In universal iPad/iPhone apps you do occasionally want to include multiple views for each viewmodel - using one view in the iPad and one view in the iPhone.
To do this, there are now (literally just now!) some attributes available to mark your views as being "unconventional" - these are:
MvxUnconventionalViewAttribute
use this to mark that your view should never be included by convention
in https://github.com/slodge/MvvmCross/blob/master/Cirrious/Cirrious.MvvmCross/Views/Attributes/MvxUnconventionalViewAttribute.cs
MvxConditionalConventionalViewAttribute
an abstract attribute - override this to provide your own custom logic for inclusion/exclusion
in https://github.com/slodge/MvvmCross/blob/master/Cirrious/Cirrious.MvvmCross/Views/Attributes/MvxConditionalConventionalViewAttribute.cs
MvxFormFactorSpecificViewAttribute
iOS/Touch only
an attribute that will include the view if and only if the detected iPhone form factor matches the current device
in https://github.com/slodge/MvvmCross/blob/master/Cirrious/Cirrious.MvvmCross/Touch/Views/Attributes/MvxFormFactorSpecificViewAttribute.cs
The last of these is probably what you want in this case - you could implement simple iPhone/iPad switching for a MainViewModel using two views declared like:
[MvxFormFactorSpecificView(MvxTouchFormFactor.Phone)]
public class MyIPhoneView : BaseView<MainViewModel>
{
// iphone specific view ...
}
[MvxFormFactorSpecificView(MvxTouchFormFactor.Pad)]
public class MyIPadView : BaseView<MainViewModel>
{
// ipad specific view ...
}
Alternatively if you want a very custom configuration, you can override all 'convention-based' behaviour - you can implement your own override of GetViewModelViewLookup - e.g.:
protected override IDictionary<Type, Type> GetViewModelViewLookup(Assembly assembly, Type expectedInterfaceType)
{
if (IsIPad)
{
return new Dictionary<Type, Type>()
{
{ typeof(HomeViewModel), typeof(IPadHomeView) },
{ typeof(DetailViewModel), typeof(IPadDetailView) },
{ typeof(AboutViewModel), typeof(SharedAboutView) },
};
}
else
{
return new Dictionary<Type, Type>()
{
{ typeof(HomeViewModel), typeof(IPhoneHomeView) },
{ typeof(DetailViewModel), typeof(IPhoneDetailView) },
{ typeof(AboutViewModel), typeof(SharedAboutView) },
};
}
}
Note that eventually you may decide that you need additional ViewModels as well as Views for the iPad app - the iPad has, after all, a much bigger screen - in this case you can add them manually. Ultimately, when your app hits a few million users, you may even decide to completely branch the tablet code away from the phone code - but that can generally wait until you hit that few million mark...
Another way to do it is to go ahead and create 2 ViewModels, but have them both subclass an abstract ViewModel, as follows:
FirstViewViewModel : BaseViewModel
SecondViewViewModel : BaseViewModel
With the corresponding views named:
FirstView.xaml
SecondView.xaml
This way, you are able to place some shared behavior in BaseViewModel, while the 2 subclasses are really just there to satisfy MvvmCross' view fetching conventions.
I recently started with MvvmCross and I am using v4.2.1. It seems that some names have changed. I am using one ViewModel with seperate iPhone and iPad views with the following:
[MvxFormFactorSpecific(MvxIosFormFactor.Phone)]
public class MyIPhoneView : BaseView<MainViewModel>
{
// iphone specific view ...
}
[MvxFormFactorSpecific(MvxIosFormFactor.TallPhone)]
public class MyTallIPhoneView : BaseView<MainViewModel>
{
// tall iphone specific view ...
}
[MvxFormFactorSpecific(MvxIosFormFactor.Pad)]
public class MyIPadView : BaseView<MainViewModel>
{
// ipad specific view ...
}