CODEWITHSUNDEEP
androidfileinputstream
Nahid OG
Nahid OG

Reputation: 131

read file from another activity

I want to read a text file that i had write in another activity using OutputStreamWriter. this is my readFromFile method in Sale.java:

private int readFromFile(String request) {

        int res = 0;
        try {
            //InputStream inputStream = openFileInput("dalassnums.txt");
            File file=new File("dalassnums.txt");
            InputStream inputStream = new FileInputStream(file);

            if ( inputStream != null ) {
                InputStreamReader inputStreamReader = new InputStreamReader(inputStream);
                BufferedReader bufferedReader = new BufferedReader(inputStreamReader);
                String receiveString = "";

                while ( (receiveString = bufferedReader.readLine()) != null ) {
                    String s=bufferedReader.readLine();
                    if(receiveString==request)  {
                        res=Integer.valueOf(s);
                        break;
                    }
                }

                inputStream.close();

            }
        }
        catch (FileNotFoundException e) {
            Log.e("login activity", "File not found: " + e.toString());
            res=0;

        } catch (IOException e) {
            //Log.e("login activity", "Can not read file: " + e.toString());

        }

        return res;



    }

And this is writeToFile method in MainActivity.java:

private void writeToFile2(String numchar) {
    try {
        //File file=new File("dalassnums.txt");
        //OutputStream outputStream=new FileOutputStream(file);
        OutputStreamWriter outputStreamWriter;
        if(numchar=="1") outputStreamWriter = new OutputStreamWriter(openFileOutput("dalassnums.txt", Context.MODE_PRIVATE));
        else  outputStreamWriter = new OutputStreamWriter(openFileOutput("dalassnums.txt", Context.MODE_APPEND));
        for(int k=0; k<imageNums.size();k+=2){
        outputStreamWriter.append(imageNums.get(k));
        outputStreamWriter.append("\n");
        outputStreamWriter.append(imageNums.get(k+1));
        outputStreamWriter.append("\n");
        }
        outputStreamWriter.close();
    }
    catch (IOException e) {
        Log.e("Exception", "File write failed: " + e.toString());
    } 
}

When performing readFromFile, it returns 0 that means file not found; I read about passing context but i don't know what context to pass; And wondering if there is any other way than passing context. Any help would be appreciated.

Upvotes: 0

Views: 1069

Answers (1)

marcinj
marcinj

Reputation: 49976

Use : openFileInput in readFromFile, look here for example:

openFileInput() and/or openFileOutput() i/o streams silently failing

Another problem is that this is invalid:

if(numchar=="1")

you should

if(numchar.equals("1"))

otherwise you compare reference values instead content of string

Upvotes: 2

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