What would be nice if there s a way to simply get all images

Question

What would be nice if there s a way to simply get all images in a file or all available resource ids for resource I know Kotlin has a walking function to grab names of files

gildor · Answer

gt get all images in a file What do you mean

amanda.hinchman-dominguez · Answer

get all images from a specific file in resource like drawable

amanda.hinchman-dominguez · Answer

i e <https kotlinlang org api latest jvm stdlib kotlin io file tree walk index html>

gildor · Answer

Do you mean load all the images from directory or tree of directories

amanda.hinchman-dominguez · Answer

it s quite possible that I just wasn t successful trying to use this for the drawable folder

gildor · Answer

It doesn t make sense for resources because all drawable resources always flat there is not tree or even directory

amanda.hinchman-dominguez · Answer

< gildor> I would ideally like to walk through one direction at the first level to grab all images

gildor · Answer

It s impossible for resources you can group them by id for example using int array resource

amanda.hinchman-dominguez · Answer

I had a feeling it was due to restribtions

gildor · Answer

Of course you can also ship your images as raw file in `raw` resource dir

gildor · Answer

but I just curious about your case

amanda.hinchman-dominguez · Answer

btw you can walk through files in a directory without recursion

gildor · Answer

of course File someDir listFiles

amanda.hinchman-dominguez · Answer

oh yeah sure just wanted to create a quick simple android with Kotlin It s cards of images sitting in a grid to display an art portfolio

amanda.hinchman-dominguez · Answer

< gildor> haha but just to be clear a file walk definitely cannot be done for a resource file I m best off using a raw file or just setting the id s in an array

amanda.hinchman-dominguez · Answer

I guess I could do that I just always feel weird having to hardcode resources with the array approach

gildor · Answer

Just put all your card images to resources then use array to group them ``` lt array name= cards gt lt item gt R drawable clubs lt item gt lt item gt R drawable hearts lt item gt lt array gt ```

gildor · Answer

It s just much easier to work with resources than with raw files and pass cached bitmaps instead of resource id

amanda.hinchman-dominguez · Answer

I have them all sitting in res drawable at the moment I didn t realize an array could occur in xml

amanda.hinchman-dominguez · Answer

I was thinking about how annoying it is but that s probably why it s better to pull images from an API in the first place I m thinking that s going to be the next phase I could maybe pull it off my dropbox

amanda.hinchman-dominguez · Answer

< gildor> atm I have one image sitting in an appwidget provider I could put those into an array

gildor · Answer

Then you can easily load all the drawables ``` fun loadDrawables arrayId Int res Resources List lt Drawable gt val icons = res obtainTypedArray arrayId val list = 0 until icons indexCount map icons getDrawable it icons recycle Must recycle array after return list ```

gildor · Answer

gt walk definitely cannot be done for a resource file But resources are flat there is no directories you probably can iterate through all the app resources but it s probably not the thing that you want to do you want to iterate through specific group of resources

gildor · Answer

There is no standard Android way to group resources using directories even if you have a few resources dirs you can do that using gradle on compile time all those res directories values will be merged and resources will be flatten

gildor · Answer

gt probably why it s better to pull images from an API in the first place This is good question Usually if images are big you load them from API but for some types of apps it doesn t make any sense if those resources are static and required to run you app Sometimes those images just dynamic so you want to change them without app update in this case load from network of course better solution It s always trade off but I don t think that grouping of images is somehow good argument to chose one of possible options

gildor · Answer

And if you load images from network one of those image downloading libraries would be very helpful it s really not so easy to write your own just many pitfalls and features to implement

amanda.hinchman-dominguez · Answer

agreed that solution you wrote is an acceptable one for the circumstances even taking care of the memory leak at the end I appreciate that

gildor · Answer

There are some use cases to load local resources using libraries like Picasso because you can use image processors api or load resources with required resolution But if it s not your case just use local resources directly it s easier and more efficient

gildor · Answer

Also add ` ArrayRes` annotation to arrayId argument it will decrease change of passing of different type resource id and function signature will be easier for understanding

amanda.hinchman-dominguez · Answer

Ah now that makes a lot more sense for such a use case Nah mine is just a quick and dirty approach to try out Kotlin with Android I m a little rusty and while I REALLY love Kotlin I ended up spending time stumbling over the XCode like features Android Studio has laughing

amanda.hinchman-dominguez · Answer

I really appreciate the direction with it though I ve always seemed to struggle a little with resources but that explanation really cleared it up for me I ll get back to you tomorrow on it it s 1 30AM over here and I definitely will make use of the annotations

gildor · Answer

Sure +1