Develop Reference

Reading and existing file in Xamarin withC#

This code works:
string file = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData), "File.text");
File.ReadAllText(file);
Pretty straight-forward, but when I display the variable "file" using a Pizel 5 simulator I get a weird path: /data/user/0/com.companyname.aikidohours/files/.local/share/File.text. I can write new data to the file and read from it. but I now want to read from an existing file and I can't figure out where to put the file. Can someone tell where to put a text file full of basic information that I need to read from in Xamarin for adnroid?
Thanks
Todd

If you want to deploy that file with your application, you can add it to the 'Assets' folder inside your_project_name.Android project.
WARNING!!! File put in this folder are READONLY!
In case this is ok for you,this is the code to access the file:
using Xamarin.Essentials;
using (var reader = new StreamReader(await FileSystem.OpenAppPackageFileAsync("file_path")))
{
string content = reader.ReadToEnd();
}

Use PrintWriter to recreate a text file in /res/raw/ with android?

I am creating an app where the configuration file needs to be re-written on startup and would like to use PrintWriter to create it. The problem is PrintWriter takes a file as a parameter. is there any way to reference a text document in /res/raw/ as File object in order to fit the parameters for PrintWriter?
I don't know if this will help but here is some code to better explain my question:
(its the basic idea but doesnt work...)
PrintWriter writer = new PrintWriter(new File("res/raw/config.txt"));
/*(I need to acces my config file... here ) */

You can't write to the res/raw directory because it is part of your apk file. You will need to either save the configuration a preference file using PreferenceManager.getDefaultSharedPreferences(Context context) or write a file to your app private directory. You can create a file like this:
PrintWriter writer = new PrintWriter(context.openFileOutput("config.txt", MODE_PRIVATE));

(Android) Read matlab file from assets

I use the jmatIO library to read a .mat file. In plain java I can set the path to the matFileReader like this
MatFileReader mfr = new MatFileReader("/theta-phi_small_param5.mat");
and I can have access to all the .mat data. Inside the android i put the .mat file to the assets folder and I tried to access it like this
mfr = new MatFileReader("file:///assets/theta-phi.mat");
but it doesn't work. How can I get the path to the mat file inside the assets folder so to read it with the MatFileReader?

Does the MatFileReader accept an InputStream? If so you can do it like this:
InputStream in = getAssets().open("theta-phi.mat");
It might also work to use:
File file = new File("file:///android_asset/theta-phi.mat");
UPDATE: Since MatFileReader doesn't support InputStream and the File solution above doesn't work I guess your best bet is to copy the file from the Assets folder to your apps External/Internal storage and from there access the file.

Get preloaded file in android

I'm new to android development and I am working on a little project. What I am having some issue with is getting access to preloaded files.
In my app, I have an XML file that I preloaded (I just simply put it in my src folder in a package). How do I access them in my classes? I need to get a File object pointing to this file so that I can use it as I would I/O files. It seems like this should be trivial, but alas I am stuck.
Lets say the file is located under: com.app.preloadedFiles/file1.XML
I've tried something along the lines of this, but have had no success:
URL dir_url = ClassLoader.getSystemResource("preloadedFiles/file1.XML");
FIle file = new File(dir_url.toURI());

I solved this in my app by getting an InputStream to the file -- something like:
myContext.getAssets().open(fileName);
//read the data and store it in a variable
Then, if you truly need to do File related opterations with it, you can write it to a private (or public) directory and do your operations from you newly written file. Something like:
File storageDir = myContext.getDir(directoryName, Context.MODE_PRIVATE);
File myFile = new File(storageDir + File.separator + fileName);
//then, write the data to the file and manipulate it -- store the name for access via File later

Accessing an app's project files on the Android platform

So in my Eclipse android project I have a pdf file that I'd like to open, I looked up the standard address on the android developer's page and I came up with this pointer:
File file = new File("Android/data/com.alex.testing.app/res/raw/jazz.pdf");
where jazz.pdf is situated in res->raw in my eclipse project,
and com.alex.testing is my package name.
Still, when I try if(file.exists()) , the function returns false (on the emulator it goes to an else I've set up to display an error message)...
Sorry for the newbie question, but I'm really stuck with this :(.

put the file in assets folder and pick the file from there
Now use Context.getAssets().open("jazz.pdf") and pass the resulting InputStream into PDf parser library

Ok, to access resources from current application you can use something like,
Uri path = Uri.parse("android.resource://<you package>/raw/<your_file.pdf>");
OR
Uri path = Uri.parse("android.resource://" + getPackageName() + "/" R.raw.<your_file.pdf>);
But I have a doubt if you are trying to use this pdf file in your application then its OK, but If you want to view this file using any third party application then I think you can't do it.
Because external application can't access application's package resources file.
So better way it to put this file in /asset directory then copy it to any public access area then view that file from that path.

//if your are stored in SDcard your location would be
"data/data/com.alex.testing/res/raw/jazz.pdf"
//you read resources from raw folder thru the below code
InputStream inputStream = getResources().openRawResource(R.raw.jazz);
byte[] reader = new byte[inputStream.available()];