Question

I want to be able to create a file from the Content Provider, however I get the following error:

java.io.Filenotfoundexception: /0: open file failed: erofs (read-only file system)

What I am trying to do is create a file whenever an application calls the insert method from my Provider. This is the excerpt of the code that does the file creation:

FileWriter fstream = new FileWriter(valueKey);
BufferedWriter out = new BufferedWriter(fstream); 
out.write(valueContent);
out.close();

Originally I wanted to use openFileOutput() but the function appears to be undefined.

Anyone has a workaround to this problem?

EDIT: I found out that I had to specify the directory as well. Here is a more complete snippet of the code:

File file = new File("/data/data/Project.Package.Structure/files/"+valueKey);
file.createNewFile();
FileWriter fstream = new FileWriter(file);
BufferedWriter out = new BufferedWriter(fstream);
out.write(valueContent);
out.close();    

I also enabled the permission

<uses-permission android:name="android.permission.WRITE_INTERNAL_STORAGE" />

This time I got an error saying:

java.io.IOException: open failed: ENOENT (No such file or directory)

Answer 1

Try this:

File parentDirectory = new File("/data/data/Project.Package.Structure/files");
if(!parentDirectory.exists())
{
    System.err.println("It seems like parent directory does not exist...");
    if(!parentDirectory.mkdirs())
    {
         System.err.println("And we cannot create it...");
         // we have to return, throw or something else
    }
}

File file = new File(parentDirectory, String.valueOf(valueKey));
file.createNewFile();

BufferedWriter out = new BufferedWriter(new FileWriter(file));
try
{
    out.write(valueContent);
    System.err.println("Now it works!");
}
catch(IOException e)
{
    e.printStackTrace();
}
// Anyway don't forget to close streams
finally
{
     out.close();   
}