Importing a .bundle for iOS with executable code - ios

I am trying to make an application in Objective C where a user can download a .mlmodel file from Google Drive and then dynamically load this model as a class and run its methods that come from CoreML's MLModel interface.
Looking at Apple's documentation, it appears I should be able to do this using bundles: "You can make your application extensible by designing a plug-in architecture. This way, you or third-party developers can easily add new features without recompiling the whole application or even having access to its source code."
My existing code downloads their .mlmodel file from Google Drive and saves it to the Documents folder. However, not finding a way to instantiate this as a class, I switched approaches, and will instead download a .bundle file from their Google Drive and then try to make the class from the files within it. I am struggling to find any examples of how to do this. First, I do not know how to get a .bundle file after making an App, setting the principal class, and setting the BundleID as described here. Second, I am concerned that although the documentation seems to indicate that what I want to achieve is possible, I have run across several SO posts that say that running any sort of uncompiled code, dynamically linked code is impossible on iOS. I would appreciate any clarity on the matter.

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Pre-load content into Documents or Library directories from XCode

I am building an iPhone app that requires preloaded content. This content is presented so that it tests the user's knowledge, but is not modified by the user. The content consists of proprietary image files and pdf files.
From what I understand, the best practice would be to store this in the app's Library or Documents directories (please inform if this assumption is not correct). In a future version of the app I might want to upload additional (not replacement) content via API, but this is not part of the initial version.
I have seen many posts and tutorials regarding obtaining paths to the Documents and Library directories of an app, and reading/writing to them. This is all good and useful, but not what I am looking for here.
I would like to preload the content into the Documents and/or Library directories, for the simulator initially, to test app in simulator; and ultimately to the release version. I would have thought this would be possible to do from XCode without writing code.
I have not been able to find a solution to this on Stack Overflow or other places on the net. Any pointers, links, solutions are welcome. I am using XCode 10.3 with Swift 4.2.
See the File System Programming Guide: File System Basics, which shows us:
The “data container” (including the Documents and the various Library folders) is for content generated/saved by the app. When, in Xcode, you mark resources as being part of the target, that becomes part of the bundle, and your app can retrieve it from there at runtime.
Theoretically, yes, you could copy data from the bundle to the Documents and/or Library folders, but, yes, you would have do that programmatically. It seems a bit wasteful to have two copies of these resources on the device, but you can do whatever you want. Generally, though, resources included in the bundle would just be be opened directly from there at runtime, not copying it to the data container (except for those cases where you would need to change it, because bundle contents are read-only).
FYI, for additional information regarding the file system, see the iOS Storage Best Practices video.

Adding and using an executable file in iOS at runtime

Suppose, I have some external executable file(call it a .swift file) that are not linked with the xcode project at compile time. That means, I did not have any of those files in my project tree when built the project.
For an example, lets say I have a file called exc.swift. This file was not included while I built the project.
Is there any way that I can execute that executable (the exc.swift) file at runtime?
In android there is a way by using DexClassLoader class. That class is responsible for executing code not installed as part of an application.
The documentation for that class is here.
Is there an iOS equivalent version of this? or in any way is this achievable?
If you are hoping to distribute the app that you are writing, then this is an absolute no-no. The app store review guidelines clearly state "Apps that install or launch other executable code will be rejected" so no app that exhibits this functionality will ever get onto the app store. You may be able to find or devise some kind of hack or workaround to get this kind of thing to work, but it will only ever be for your own amusement.

Steps to develop an iOS app to open PSL files?

In this project I've to develop an iOS application which reads the .psl files and arranges the data in the relevant section. For eg: the inbox messages from the psl file into the app's inbox folder and so on.
Can anyone guide me regarding the steps? And how would my project proceed also tell the workflow of this whole process.
The first thing you're going to have to tackle is to figure out how to get the file onto the phone. If you're getting it from the web; you could register as a sharable-target for that file type, or you could potentially integrate the DropBox api or something similar.
Once you have the file; you'll have to develop something to parse the file and use it as a datafile. Depending on the size and complexity of the file there will be different possible approaches to this, and you'll need to figure out what's going to be performant for you.
Then you'll build view controllers that leverage your model and make awesome things happen on the phone.
Your question is extremely general; so this is a very general answer. To me; the immediate critical questions are: how to get the file to the phone; and how to read the file format without loading the whole thing into RAM at one time?

adding a library for iOS app

I am building an iOS app that requires the use of the glm library(link to site). I don't necessarily want to place the entire library in the app folder every time I want to use it. Is it possible to
A) point xcode to the library folder so it knows where to find the headers
or
B) place the library in the standard iOS library folder.
Im sure this is something developers must do all the time, but Ive been unable to find a simple solution on the web.

iOS custom framework, libraries, and bundles

I have a general question regarding bundles, libraries and custom frameworks on the iOS. I've seen many topics about this on SO and searched far and wide on the net, but I still can't come to an answer without finding another site or post contradicting or confusing me some more. If someone could give me a solid answer to the below questions regarding what is allowed on the iOS or what would get rejected I would be really grateful.
I've seen posts and sites say that you cannot create bundles on the iOS. Does this also apply to bundles with only images in them?
Is it possible to create a library with .xib files in them? If not then how would one go about including one if custom frameworks are not allowed?
Does using a xCode dynamic library put my application for grounds of rejection (ex. libxml2.dylib)?
Apologies if this is too general or mentioned multiple times, but this whole library and what is allowed and what isn't allowed just doesn't seem to be very clear for me. What I am trying to do is to create some apps and perhaps include some controls that I frequently use in some sort of library or bundle, but I would like to know my limitations before moving further.
1.: No, you cannot create any framework even if it contains images only, as you can't write to the root partition of the iOS filesystem (the part where /System/Library/Frameworks resides).
Of course, if jailbreaking is an option, then all this stuff becomes invalid. You do what you want with a jailbroken phone, so you can create frameworks, add libraries to the filesystem etc.
2.: Yes, it is possible to create a library with XIB/NIB files with it, but then you'll need to share both the source or a static library built from the sources AND the XIB files and guide the other developers to do so in order iOS to correctly handle your library and be able to build the UI from the InterfaceBuilder files.
3.: No, because those libraries are already on the iPhone, you don't have to hack it to get them on the filesystem. libxml2, libsqlite3, etc. are allowed and can be used in any AppStore app.

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