I have made like an "Asteroid" copy, that works pretty well! I made it with different modules (enemies, controls and background). Now I have also made like a starting screen, where the player can choose to play the game, view highscores etc.
The problem is that I have no clue how to implement this into a storyboard.. I might have misunderstood the use of modules.
I am starting in a Scene1, which is the intro+buttons to start the game. Next, I want to move to scene2(when player presses start button), and that seems to be no problem, and scene 1 gets purged. But when I die, I want to move to scene1 again. Problem is that some listeners dont get removed, and the game crashes shortly after scene switch.
I guess the main problem is that in my scene2, I have put in require("background"), enemies and controls in my enterscene, which I dont know how to remove when it should be purged.
Ive entered all of the modules and put them in the same group that gets purged on exitscene, but not everything gets removed.
How do you think I would fix this the easiest way? I am very new to Corona and still in a early learning stage.
Display objects, like display.newImageRect()'s and display.newText() that are created in the createScene() function and added to the "group" display group will be automatically removed when the scene is purged.
Any timers, transitions, or audio.plays that have onComplete handlers, as well as network requests and any event handler that attaches to the Runtime must be removed by hand. If you're various object you are creating are doing any of these things, their remove functions should undo these actions so that removing them will clean them up.
I find it best if I'm adding runtime handlers, timers, etc. to do it in enterScene() and make sure I undo them in exitScene(). Then if its something that is done in createScene() it should be cleaned up in destoryScene().
modules are kind deprecated to start.
Second, putting stuff in other files and calling them with "require" is supposed to be used to call libraries, not code that will run. "require" is not a dofile, or a eval, it will run once, and only once (when the first "require" of the file is made).
If you still want to put things in other files, like loading your background, you need to do a "background.lua" file that has a "background.load()" function and a "background.unload()" function, and call them in appropriate places.
Related
My team and I have to make a license plate scanning app as a school project. With that, we have comments and pictures which can be added to cargo. Whenever the user scans a plate they also get the chance to change the checked info in case of a mistake. The problem is that whenever we delete data from the scanned plate it doesn't show on the screen that it has been deleted until we go to another screen. The same goes for the lazy column which we use for inserting new instances of comments and pictures. The data doesn't show on screen until we turn our screen or go back to another screen. private val pictureList = mutableListOf() is what we use for the pictures and for the text we use var countryCode by remember { mutableStateOf(CountryCodeText) }
var licenseNumber by remember { mutableStateOf(LicenseNumberText) }. pictureList is a global variable and the other ones are local variables which use global variables in the mutableStateOf. How can we make sure that the UI updates whenever the data changes? In advance I want to say thanks for the help! (Code is written in Kotlin and jetpack compose)
Just replace the mutableListOf() with a mutableStateListOf(...), and prefer to keep all the state logic confined to a ViewModel. The viewmodel should preferably be only one for the entire app, and the entire app should have only one activity.
The viewmodel should act as a single source of truth for the entire activity's UI state, while also handling all the updates to the UI efficiently.
The #Composables should only be incharge of displaying the state, and sending events to the viewmodel to update the state, for example, an onClick event may be sent up to the viewmodel by a button too trigger a state change in another part of the app.
Take this codelab to learn all about state in Compose (Well, not all, really, but good starter).
Also, changing screens destroys all the #Composables of the current screen, and so when you ce back there, all the #Composables are re-created, and the correct data is fetched. If you wish to trigger "recompositions" upon changing a variable, you must ensure that the concerned variable is a state-holder, i.e., initialized with one of the pre-built state initializers, like mutableStateOf(), or mutableStateMapOf, etc.
We usually have a mutableState*Of format for determining whether a pre-built state initializer is available. The most common ones are covered, obviously, but if not, you'll need to create a new type of initializer yourself, and if that is not something you know how to do, currently, you can just go about checking whether the type of data you wish to store is Immutable. If so, you can just wrap it in a mutableStateOf<DataType>() call, and it will trigger the recompositions. Know that this is not as efficient as pre-built initializers, but definitely gets the job done.
Also, I suggest you take the compose-pathway to get the basics down. It covers everything ranging from creating a simple UI using basic pre-built Layouts to creating a complex animation-driven application using custom Layouts.
So, definitely a lot to take it, but I hope you get there.
Happy composing,
My application has deep navigational chains of 8+ screens deep (Wizard-style). When i'm editing a View Controller, and i want to make a quick visual change and re-test, As a tester, I have to go through the full flow to end up where I was before recompiling, in the same Data state. Is there a way that Xcode can somehow preserve the application state, and re-run the same view controller?
If there was an automated way to detect the last launched screen, and re-display it after the recompile, that would save a lot of developers a lot of time.
I realize something like this can be built custom. Something like:
IF A Certain Debug Flag is ON:
- Retrieve from NSUserDefaults the Class Name of the last controller used, and redisplay it.
The problem with this is: Data State and Navigation State will not be preserved. Also, all other object state which invokes and depends on your controller will not be included. That's why I need a more universal solution.
IF A Certain Debug Flag is ON: - Retrieve from NSUserDefaults the Class Name of the last controller used, and redisplay it.
The problem with this is: Data State and Navigation State will not be preserved.
But this is exactly the problem that the built-in state saving and restoration mechanism is intended to solve, is it not?
https://developer.apple.com/library/ios/featuredarticles/ViewControllerPGforiPhoneOS/PreservingandRestoringState.html
I recommend you use a User Interface target and then create an XCTestCase that works on your view controller and exercise it. Use the new record button in Xcode 7 to get you started with the test case. Familiarize yourself with some of the new queries it uses for some of the dynamic information you may be creating.
Another option would be to inject your test case's UI state into the application delegate in the setup function of an XCTestCase. Then it will need custom logic to navigate to the correct view controller. Then your test case could focus on just that ViewController once the Application delegate has navigated to it.
Of course you can use the debugger and breakpoints in the Test Case and your View Controller while UI Testing. By "scripting" this you do significantly less manual clicking on a device to test a ViewCOntroller
Also you've now got a Test! Hopefully worth something to you down the road when you change something
I am using Resource Change Listener to track the changes done to my java project. When i move a class from one package to another, it some times triggers Remove even and some time Add event. Is this correct. I was expecting add event on the 2nd package and remove event on the 1st package. I need to track both add and remove, please let me know how this can be done...
I would expect you to get two IResourceDelta with ADDED and REMOVED kinds. Depending on exactly how the class move is done these might be in two separate IResourceChangeEvent events or they may be in one. The resource delta flags may also have MOVED_FROM and MOVED_TO set.
I'm looking into ways to save memory in Sencha Touch 2. I see two options, as I'll describe below.
I'd like to get advice on the difference of memory consumption between the two options, and to know if I'm missing anything.
Memory-saving options
Remove and Destroy
Remove unused components from their containers, and destory them. When they're needed again, re-create them.
Advantage:
this approach can be greatly assisted by container ref's 'autoCreate' option and by container config's 'autoDestroy' option.
Disadvantage:
to re-create the view as it was before destruction, you need to make sure every important piece of information you wish to recreate (e.g. scroll-location in list, map-center in map) is kept as state elsewhere.
Remove
Remove unused components from their containers WITHOUT destroying them. When they're needed again, re-attach them to their containers.
Advantages
no need to keep GUI-related information somewhere as state.
the component could be updated even when not appearing in the DOM.
Disadvantages
the component is cleared from the DOM, but the Sencha object is still kept in memory
you'd need to keep detached components somewhere, and make sure to check for - and attach - existing ones before creating new ones
I also posted this on the Sencha forums: http://www.sencha.com/forum/showthread.php?200314-Memory-Management-Options
I got the following, rather general answer:
If you remove the component but do not destroy it, you minimize DOM size but of course you still have that component in device memory. The benefit is since DOM size is down, you have better performance and DOM size is going to have a larger impact than having some components in memory.
I'm working with a document-based core-data OS X application. The problem I'm having is that whenever I edit any field on the document, after I press tab or click to something else (i.e. I finish editing/change focus), the document is marked as clean and undo is reset. When I try to save the file, however, the resulting document opens without the data I entered. What might be the problem, or, any pointers on where to look to fix this? Here's some stuff I know and things I've already tried:
I know it's not somehow saving because it never stops at the breakpoint in my overridden writeSafelyToURL:(NSURL *)inAbsoluteURL ofType:(NSString *)inTypeName forSaveOperation:(NSSaveOperationType)inSaveOperation error:(NSError **)outError and it also never sends an NSManagedObjectContextDidSaveNotification.
The documents are packaged in an NSFileWrapper directory with the core data store inside (and also some other files). I access the entities through an NSObjectController and a couple NSArrayControllers. It happens with both core data properties and manually registered changes in the rest of the file wrapper.
Update: At the suggestion of Martin, I tried NSUndoManager's notifications, and all I can seem to glean from it is that more than one undo manager is in play. If I add an observer for NSUndoManager, it won't post if I specify an object, and then if I don't, the notification object is not equal to [self undoManager]. I added updateChangeCount to my category on NSPersistentDocument, and it never gets called. setDocumentEdited basically confirmed that something about losing first responder is passing NO into that method. What could be causing this, and how can I fix it?
You could break on the method setDocumentEdited: of NSWindow to see which operation updates the change status.
In addition updateChangeCount: of NSDocument might be a place to take a look at.
NSUndoManager also posts several Notifications which can give additional hints what to look at.
The answer is actually pretty silly considering how long this stumped me. I was working on some objects on load, and I accidentally set [[self undoManager] disableUndoRegistration] at both the points where I should disable and enable. It was a little more than that, though. A related element in Interface Builder needed to be checked Prepares Content. When I had done both those things, the problem vanished.