There is a file strings.xml:
<?xml version="1.0" encoding="utf-8"?>
<string name="param">0</string>
need to read a variable named "param" and change it to another int variable
or read and write to a file located in this APK, for example /assets/config.txt?
Don't try to modify the APK.
You should consider using other "persistent storage" options for your Android application ... you don't really want to be modifying the contents of your APK on the device. Shared Preferences, External Storage or SQLite Databases are among the options you have. You may want to read more documentation about these options on the Android developer area here
You cannot write/modify file in assets folder runtime.
Please check How to write files to assets folder or raw folder in android?
Related
Is it possible in Android, to manually add a file inside a project and then, modify it? Example:
"I have a test.txt file in the following path: "app/src/data". I would like to make a method to write a given String in the test.txt file."
Is that possible? I been looking everywhere, but can't seen to do such an easy task.
If you mean modifying files inside the APK itself then it's not possible. Besides, the folder structure you see in the project is not the final structure on the APK (just unzip your APK, it's a .ZIP really): Fpr example, the source directory is all compiled into a classes.dex. The res/ directory is compiled and fully copied ...
Take a look at How to write files to assets folder or raw folder in android?
and https://developer.android.com/training/basics/data-storage/files.html
You can read raw files stored in /res/raw, or assets stored in assets/ , but you cannot modify stuff inside the APK itself.
What you can do is create and modify as many files as you wish from the different places Android gives to any app, such as:
CACHE directory (context.getCacheDir() -> /sdcard/Android/data/your.package/cache
External files (context.getExternalFilesDir() -> /sdcard/Android/data/your.package/files
Arbitrary directories in the SDCARD.
I am trying to learn android programming. As a beginning, I am trying to understand the internal file system & accessing them. Any help is highly appreciated. Following are my challenges:
How to create a 'TEST' folder through the android emulator/Android device monitor? I need to create the folder where the alarms, download, DCIM folder are present.
What is the absolute directory path to the 'TEST' folder created? Is it possible to access the TEST folder using the code below:
List<File> list = Environment.getDataDirectory()+"/TEST".listFiles();
Does any permission to be mentioned in the manifest for read/write to internal storage?
PS: I use Android Studio.
You would want something along the lines of
File TEST = new File(Environment.getExternalStorageDirectory(), "TEST");
TEST.mkdir(); // make directory may want to check return value
String path = TEST.getAbsolutePath(); // get absolute path
and permissions
<manifest ...>
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
...
</manifest>
Further reference
Android Open External Storage directory(sdcard) for storing file
How can I get external SD card path for Android 4.0+?
https://docs.oracle.com/javase/7/docs/api/java/io/File.html
File file = new File("storage/emulated/0","yourfoldername/");
This worked for me if this doesn't help, then in use
File(Environment.getobbdir(),"yourfoldername");
I'm trying to load words into an arrayList from a txt file in the assets folder in my android program, and looking at the api, it says that AssetManager.list(String path) will "Return a String array of all the assets at the given path."
Does that mean that if I have a text file, words.txt, and I put in "words.txt" as the parameter for AssetManager.list(String), that it will return a String array of all the words in the txt file?
If not, how would I go about reading a txt file into an array in my android program?
I couldn't find a definition for "asset"
I'm using eclipse.
EDIT:
I'm not just asking what an asset is, I'm also asking about a specific method in the api and how to load strings into an arrayList
Android offers one more directory where you can keep files which also will be included in package. This directory called /assets. The difference between /res and /assets is that Android doesn’t generate IDs for assets content. You need to specify relative path and name for files inside /assets.
assets/
This is empty. You can use it to store raw asset files. Files that you save here are compiled into an .apk file as-is, and the original filename is preserved. You can navigate this directory in the same way as a typical file system using URIs and read files as a stream of bytes using the AssetManager. For example, this is a good location for textures and game data.
Source
Asset Usage Example
assets is place where you can normal files which you want to read in application as some point whenever needed. You save your files/directory's. And read in your application from input streams but you cannot write.
As far res concerned, they resource files which you can refer directly in your code. like strings, array of strings,images (drawables),style(android specific like css in html) and there is raw folder which stores all files binary and generates id for it.
I am developing an application with Android/Java. I need to attach a list of audio files into my java library. So that the developer can use the library and play the audio files. How can I attach the audio files into my Java library and how to call them as file path to play them?
If you are creating an Android Library, you can put your audio file in the raw folder. People using your library can refer to it using com.example.yourlibrary.R.raw.sample_audio_file.
I hope this is what you were looking for. The file will be embedded when the library is created.
If you have specific audioFiles then add them to the special resource folder and refer to them as getResourceAsStream . If you want user to use their own files - provide the variable for the folder path and make a filter to use only specific files, i.e *.mp3.
If they are stored in specific resources folder, why not to create special Accessor class for the developers to use it? Like you will have a *.jar file that will contain files in the separate resource folder with the Accessor to work with them.
After searching 1 hour i do not found any solution to my problem.
I want to move a file from sdcard to assets folder and also overwrite the existing file in assets folder (both file are sqlite database have same name with just a little difference in data )
??
Actually, The behaviour of the android .apk file is read only so the directory structure which are in that apk file follows the same, So no one can write this files or make changes on that at runtime,that's why You can't make a changes in /asset folder at runtime. you can read file from it (means copy files which are available in asset to any internal storage or /sdcard but not write it to vice-versa)
Its apply on all the directories which are build in .apk files. As per docs.
Assets folder are not Writable it is only readable so you cant copy from sdcard to assets, yes you can copy from assets to sdcard
If you want other apps not to access your database then what you can do is
Download the database from website. create a temp database also in app directory.
getDatabasePath() this will give you the path of the dummy database you have created now replace this with the one you downloaded.
PS.: User and apps having root access still able to access it and you cant do anything in that scenario