I want to write an android application that can parse files. I have figured out the parser part of it but now I m stuck at how to actually input the files. The files can actually be anything - music files, image files, text files or video files. The parser recognises the file format and parses it accordingly. Can anyone tell me how to write the UI and code to actually input files (I am programming in java in eclipe). Ideally the user should be able to go through the folders in the phone, just like we do in the computer, and then choose which file.
Any help is greatly appreciated !
So what you need I think is a file browser or manager, right? Unfortunately, Android doesn't provide a native file manager,and you have two choices to select files in the sd card.
There are some free third-party file managers,such as ES file manager and OI file manager. They provide hook for the developers to call via Intent. I am using OI. It's open-source.
You can also implement your own file manager. Well, it would be a little more difficulty than the 1st solution and you have a lot of work to do. I may suggest you use a listView, and list the dirs in the sd card. You may use android.os.Environment class to check the state of the sd card and use java.io.File to get info about the dirs and files.Also, see here to learn how to read files from SD card.
Related
I have code for creating an internal file, there is random algorithem that create the data stored in it and i want any app to have the same file with the same binary data in it.
so i need to make the file on my desktop and add it to internal files some how.
my question is what do you think is the best way to do it.
i thought to locate it in my project, read it, and write it to internal files.
the problem is, i dont know where to locate my file in android studio so that it will be included in the external files and then where to read it from.
thanks. =]
hope i made myself clear.
Put it in src/main/assets/.
You can then access your file with AssetManager and do whatever you want with it.
From the Android Developers website:
main/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.
You need to move that into the assets folder. From there you can refer to the file.
So I have some files I want my Android App to access, read and write.
I want to store it internally. Where can I put these files in my Java Project so they are accessible or can this not be done?
There are three ways to achieve this, and according to your requirements select the approch
on SDCARD
This is the normal SDCARD/in-build SDCARD in newer smart phones. you need to create specific folder structure and put your files there, here you can do file read and write both
but this in insecure because accessible to all the application
on Internal Storage
This is given as Applicaiton specific storage where you can create the file and do the operation, this is most secure way to do it, but this is generated run time so you can not push the files directly, you can put your files in RAW or ASSETS and copy that here
RAW and ASSETS
This is in the code structure only and only read access is given to this folder, you can not change this file run time.
if you select any one of this approach then simple goggling will show you the sample code.
You can read or write files in the path of your internal storage as
data/data/package_name/files . I had already answered a similar question you can check it out.
I'd like to take a few zip files - file1.zip file2.zip file3.zip etc. and create an APK file which contains them and when installed simply copies them to a specified directory on the sd card of the phone.
Can this be done in just a few lines of code? I really appreciate any input. Thank you.
Anything you put in res/raw is available as a resource you can work with once your app is installed. I'm curious why you want to move zip files to the device without having a "real" app to go with them.
I want to decouple data from code on my Android application, and I am not sure of the best way to do that.
For instance - with the Linux Mahjongg game you can add new tiles to the game by dropping a specially formatted file into a specific directory. The Mahjongg game checks that directory when it starts up.
I want to do the same thing with my Android app - I want to be able to install the app, and then have separate installs for different data files. It's the data file installs that have me hung up. I do not want to have to set up my own server and write my own download code.
You can ship the data with the installer app, then use Input/Output Streams to copy the data from the assets or raw dirs.
Check this out:
Ship an application with a database
The answer has an implementation of in/outputstream. You don't need to use a db, just copy the file to ext storage.
One important detail: if you put the file in assets, it will be shipped compressed, and the phone/tab will try to uncompress the file in its entirety in memory. One (hocky) way to avoid that is to name the file .mp3. Assets in .mp3 format are not compressed. (Hey! I said it was hocky!)
The installer app can either uninstall itself by using ACTION_DELETE in an intent (see http://android.amberfog.com/?p=98 for details) or just show a msg to the user that it's safe to delete the data app.
HTH,
llappall
by dropping a specially formatted file into a specific directory
You can do that on external storage. Create a directory, and check it when your app starts up for new files. Tell the user they have to stick the magic files in the magic directory for it to work.
I am creating android application which contains DB that needs to be hidden(not able to access by the user)in the SD Card. Can anyone tell me how to do this?
Any file stored on the SD card is accessible both by applications running on the phone, and by users who have mounted the SD card (both while it's in the phone and otherwise).
You can change the file properties to make it 'hidden', but it will still be easily found. There is no way to make a file on a public partition like an SD Card 'secure' in the manner you describe - users will always be able to copy, delete, and potentially change the file.
The best solution to your problem is to look into ways to encrypt your database to record it securely. You won't be able to prevent users from deleting or copying the file, but you should be able to make it difficult for them to read data from it or modify its contents.
For an easy solution, just prefix the db file with a . (like .dbfile). This will hide the file on Linux based systems, including android.
I am assuming that you want to hide the file to prevent users from accidentally deleting/changing it.
SD cards cannot be secured in the fashion you seek.
just name the file start by ."Dot"... ".myFolder/.myfile"
You can create a folder whose name starts with a dot(.) example (.dbfiles) android See these folders as configuration folder and do not show content of these folder in applications like gallery,music player...You can see these folders with advance file explorer like Es File explorer
Sdcard you cant't! Internal app data partition is the place for you.