Can anybody please help me out on how to destroy a dynamically created part. I am using partservice to create a part dynamically from a partdescriptor. i know we can hide the created part, But i think the context still has the object saved in some list so it is not removed from the heap space which in turn increases the memory. so is there a way where i can destroy the part like how we dispose a widget in SWT.
Add removeOnHide to the Tags section of the part descriptor (and make sure it is copied to the created part!). This constant is declared in EPartService.
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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,
I have an application that cover a wide number of use cases each with completely independent workflows but workflows are pretty static after installation.
I have therefore created an HBox placeholder that will load the workflow for an installation.
Is there a way to dynamically load a section of the fxml from a database or a separate file archive? This fpml will have to have its own set of images and resources needed to achieve the workflows functionality.
TBH, I don't know where to start on this one.
Regards
I do not quite understand your problem. You can modify the scene graph at any time you want. So, of course it is possible to load a part of the scene graph from an FXML file at any time and hook it up to the already existing part. In your controller you have access to your HBox placeholder and when you have loaded the second part of the scene graph you can just add it via hbox.getChildren().add(newpart), were newpart is the root node of your second scene graph part. Of course you have to make sure that the layout works correctly for your constellation.
Your question seems nonsense because the FXML is always loaded dynamically. My guess is you are confused because most of the examples use FXML in the same bundle as the classes and so are loaded trough the getResource method. But the FXML loader takes any kind of InputStream, so you can just open a database blob or a file as an InputStream and give that InputStream as an argument to the loader. Be sure to catch the runtime exceptions though :)
Hope this helps.
i'm facing one problem about attaching movieclip from loaded movie, so basically we have a Map
Map.loadMovie("SimpleMap.swf");
in this map there's a npc dialogue with its name "Dialogue1" I want to attach it to the client. It should be basically something like
_root.attachMovie("Map.Dialogue1", "dialogue", _root.getNextHighestDepth());
but it seems I can't get it to work. Anyone can help?
Note: Also I want to attach the movieclip to the client instead of the map, else I would use Map.attachMovie
it's been a while since I wrote any Actionscript 2 stuff, but have you tried removing the quotes around Map.Dialogue1 ? - If I remember correctly passing a string would make Flash look for the symbol in the library, not from the global or current scope...
_root.attachMovie(Map.Dialogue1, "dialogue", _root.getNextHighestDepth());
If you want you can import mx.core.UIObject and then use the method _root.createObject() (or if it is O-O use createClassObject()).
It is going to attach the "npc dialog" as an object... you need to specify the linkage name and give the instance a name. So for example if you called the dialog "npc_dialog" in the library then use:
_root.createObject("npc_dialog", "my_npc", _root.getNextHighestDepth());
Here is something else you can try... go to the library and drag a instance of the movie onto the stage somewhere where it will not be seen, like for instance on the next key frame or off the stage then try to run attachMovie().
What happens is flash will compile the clip in the most efficient way possible so if it sees you imported a package but did not use it then it will ignore this class in the compiled clip... so when you go to run and it tries to attach the movie it can't find it.
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 want to create a new object so as to instantiate and use it several times;
For example, if I want to create an object that has a label and a button inside, how do I? I created a new NSObject but inside it has nothing, then how do I make everything from scratch since there was a viewDidLoad for example (obviously, since it has a view)?
thanks!
Your questions lead me to think that you're really just starting out. There's nothing wrong with that, but rather than trying to summarize several megabytes of documentation in a few paragraphs, I'm just going to point you to the iOS Starting Point. I think that you're just trying to create a container that can hold other UI components? If so, use a UIView for that. However, don't jump in and try to get something specific done without first reading through some of the Getting Started documents -- you'll just end up back here, and we'll just point you back to the docs. You might like the Your First iOS Application guide, as that lets you get your feet wet but explains things along the way.