FileInputStream and FileOutputStream

Question

I created a .txt file and want to save the data I type into a textbox into the file. And if I click on a button I want to load the data I saved out of the file. I have the code for both, but it does not work, I hope you can help me if I have some mistakes :)

Load out of file:

public void Liste() throws FileNotFoundException {
    try {
        FileInputStream instream = openFileInput(Environment.getDataDirectory()
                + "/assets/bmiwerte.txt");
        if (instream != null) {
            InputStreamReader inputreader = new InputStreamReader(instream);
            BufferedReader buffreader = new BufferedReader(inputreader);
            String line, line1 = "";
            try {
                while ((line = buffreader.readLine()) != null)
                    line1 += line;
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    } catch (Exception e) {
        String error = "Fehlermeldung!!!";
        error = e.getMessage();
    }
}

Save into file:

public void SaveList(View view) {
    //Pfad, im privaten Speicherbereich Environment.getDataDirectory();
    File file = new File(Environment.getDataDirectory() + "/assets/bmiwerte.txt");
    try {
        OutputStreamWriter fdg = new OutputStreamWriter(new FileOutputStream(file, true));
        fdg.write("" + this.weight);
        fdg.close();

        OutputStreamWriter asdf = new OutputStreamWriter(new FileOutputStream(file, true));
        asdf.write("" + this.height);
        asdf.close();
    } catch (FileNotFoundException e) {
        e.printStackTrace();
    } catch (IOException e) {
        e.printStackTrace();
    }
    Intent intent = new Intent(this, MyList.class);
    startActivity(intent);
}

so first of all is your file in your location and do you added permission to read it in your manifest ?? — Sree, Oct 08 '15 at 11:09
C:\Users\Admin\AndroidStudioProjects\MyFirstApp\app\src\main\assets\bmiwerte.txt — linuxman, Oct 08 '15 at 11:11
i am not understanding why you are calling Environment.getDataDirectory() buy keeping file in assets — Sree, Oct 08 '15 at 11:13
I debuged the app, but it still does not work yes the file is in the path i posted aboth — linuxman, Oct 08 '15 at 11:13
the getdatadirectory() is to get the path. i can be wrong, please correct me if so — linuxman, Oct 08 '15 at 11:13
getdatadirectory() always return a external path and your file is inside your project right (inside asset folder) — Sree, Oct 08 '15 at 11:14
yes, but i am not using the emulator i execute the app on my mobile phone — linuxman, Oct 08 '15 at 11:16

Vitaliy A · Answer 1 · 2015-10-08T11:18:56.860

0

Add permissions to AndroidManifest.xml file:

<manifest ...>
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
    ...
</manifest>

Edt: Also use Environment.getExternalStorageDirectory() instead Environment.getDataDirectory() its ReadOnly .

edited Oct 08 '15 at 11:18

answered Oct 08 '15 at 11:04

Vitaliy A

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1

`READ_EXTERNAL_STORAGE` is not needed, because it's implicit with `WRITE_EXTERNAL_STORAGE` – Phantômaxx Oct 08 '15 at 11:12
See edited answer. {Environment.getDataDirectory()} is read only. – Vitaliy A Oct 08 '15 at 11:15
1

Look he is keeping file inside assets folder – Sree Oct 08 '15 at 11:16
1

... which **can't be written to**. – Phantômaxx Oct 08 '15 at 11:17
2

@linuxman Yes (as FrankN.Stein noted), it (asset folder) is read-only. – hata Oct 08 '15 at 11:18
1

@VitaliyA dear you cant write a file in asset folder – Sree Oct 08 '15 at 11:22
can i use getExternalStorageDirectory(), for input and output? – linuxman Oct 08 '15 at 11:24
1

@linuxman please google about how to read a file from asset folder and you cant write to a file in asset folder – Sree Oct 08 '15 at 11:25

FileInputStream and FileOutputStream

1 Answers1